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// types.cc -- Go frontend types.
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "go-system.h"
#include <ostream>
#include "go-c.h"
#include "gogo.h"
#include "go-diagnostics.h"
#include "go-encode-id.h"
#include "operator.h"
#include "expressions.h"
#include "statements.h"
#include "export.h"
#include "import.h"
#include "backend.h"
#include "types.h"
// Forward declarations so that we don't have to make types.h #include
// backend.h.
static void
get_backend_struct_fields(Gogo* gogo, const Struct_field_list* fields,
bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields);
static void
get_backend_slice_fields(Gogo* gogo, Array_type* type, bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields);
static void
get_backend_interface_fields(Gogo* gogo, Interface_type* type,
bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields);
// Class Type.
Type::Type(Type_classification classification)
: classification_(classification), btype_(NULL), type_descriptor_var_(NULL),
gc_symbol_var_(NULL)
{
}
Type::~Type()
{
}
// Get the base type for a type--skip names and forward declarations.
Type*
Type::base()
{
switch (this->classification_)
{
case TYPE_NAMED:
return this->named_type()->named_base();
case TYPE_FORWARD:
return this->forward_declaration_type()->real_type()->base();
default:
return this;
}
}
const Type*
Type::base() const
{
switch (this->classification_)
{
case TYPE_NAMED:
return this->named_type()->named_base();
case TYPE_FORWARD:
return this->forward_declaration_type()->real_type()->base();
default:
return this;
}
}
// Skip defined forward declarations.
Type*
Type::forwarded()
{
Type* t = this;
Forward_declaration_type* ftype = t->forward_declaration_type();
while (ftype != NULL && ftype->is_defined())
{
t = ftype->real_type();
ftype = t->forward_declaration_type();
}
return t;
}
const Type*
Type::forwarded() const
{
const Type* t = this;
const Forward_declaration_type* ftype = t->forward_declaration_type();
while (ftype != NULL && ftype->is_defined())
{
t = ftype->real_type();
ftype = t->forward_declaration_type();
}
return t;
}
// Skip alias definitions.
Type*
Type::unalias()
{
Type* t = this->forwarded();
Named_type* nt = t->named_type();
while (nt != NULL && nt->is_alias())
{
t = nt->real_type()->forwarded();
nt = t->named_type();
}
return t;
}
const Type*
Type::unalias() const
{
const Type* t = this->forwarded();
const Named_type* nt = t->named_type();
while (nt != NULL && nt->is_alias())
{
t = nt->real_type()->forwarded();
nt = t->named_type();
}
return t;
}
// If this is a named type, return it. Otherwise, return NULL.
Named_type*
Type::named_type()
{
return this->forwarded()->convert_no_base<Named_type, TYPE_NAMED>();
}
const Named_type*
Type::named_type() const
{
return this->forwarded()->convert_no_base<const Named_type, TYPE_NAMED>();
}
// Return true if this type is not defined.
bool
Type::is_undefined() const
{
return this->forwarded()->forward_declaration_type() != NULL;
}
// Return true if this is a basic type: a type which is not composed
// of other types, and is not void.
bool
Type::is_basic_type() const
{
switch (this->classification_)
{
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_BOOLEAN:
case TYPE_STRING:
case TYPE_NIL:
return true;
case TYPE_ERROR:
case TYPE_VOID:
case TYPE_FUNCTION:
case TYPE_POINTER:
case TYPE_STRUCT:
case TYPE_ARRAY:
case TYPE_MAP:
case TYPE_CHANNEL:
case TYPE_INTERFACE:
return false;
case TYPE_NAMED:
case TYPE_FORWARD:
return this->base()->is_basic_type();
default:
go_unreachable();
}
}
// Return true if this is an abstract type.
bool
Type::is_abstract() const
{
switch (this->classification())
{
case TYPE_INTEGER:
return this->integer_type()->is_abstract();
case TYPE_FLOAT:
return this->float_type()->is_abstract();
case TYPE_COMPLEX:
return this->complex_type()->is_abstract();
case TYPE_STRING:
return this->is_abstract_string_type();
case TYPE_BOOLEAN:
return this->is_abstract_boolean_type();
default:
return false;
}
}
// Return a non-abstract version of an abstract type.
Type*
Type::make_non_abstract_type()
{
go_assert(this->is_abstract());
switch (this->classification())
{
case TYPE_INTEGER:
if (this->integer_type()->is_rune())
return Type::lookup_integer_type("int32");
else
return Type::lookup_integer_type("int");
case TYPE_FLOAT:
return Type::lookup_float_type("float64");
case TYPE_COMPLEX:
return Type::lookup_complex_type("complex128");
case TYPE_STRING:
return Type::lookup_string_type();
case TYPE_BOOLEAN:
return Type::lookup_bool_type();
default:
go_unreachable();
}
}
// Return true if this is an error type. Don't give an error if we
// try to dereference an undefined forwarding type, as this is called
// in the parser when the type may legitimately be undefined.
bool
Type::is_error_type() const
{
const Type* t = this->forwarded();
// Note that we return false for an undefined forward type.
switch (t->classification_)
{
case TYPE_ERROR:
return true;
case TYPE_NAMED:
return t->named_type()->is_named_error_type();
default:
return false;
}
}
// If this is a pointer type, return the type to which it points.
// Otherwise, return NULL.
Type*
Type::points_to() const
{
const Pointer_type* ptype = this->convert<const Pointer_type,
TYPE_POINTER>();
return ptype == NULL ? NULL : ptype->points_to();
}
// Return whether this is a slice type.
bool
Type::is_slice_type() const
{
return this->array_type() != NULL && this->array_type()->length() == NULL;
}
// Return whether this is the predeclared constant nil being used as a
// type.
bool
Type::is_nil_constant_as_type() const
{
const Type* t = this->forwarded();
if (t->forward_declaration_type() != NULL)
{
const Named_object* no = t->forward_declaration_type()->named_object();
if (no->is_unknown())
no = no->unknown_value()->real_named_object();
if (no != NULL
&& no->is_const()
&& no->const_value()->expr()->is_nil_expression())
return true;
}
return false;
}
// Traverse a type.
int
Type::traverse(Type* type, Traverse* traverse)
{
go_assert((traverse->traverse_mask() & Traverse::traverse_types) != 0
|| (traverse->traverse_mask()
& Traverse::traverse_expressions) != 0);
if (traverse->remember_type(type))
{
// We have already traversed this type.
return TRAVERSE_CONTINUE;
}
if ((traverse->traverse_mask() & Traverse::traverse_types) != 0)
{
int t = traverse->type(type);
if (t == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
else if (t == TRAVERSE_SKIP_COMPONENTS)
return TRAVERSE_CONTINUE;
}
// An array type has an expression which we need to traverse if
// traverse_expressions is set.
if (type->do_traverse(traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
return TRAVERSE_CONTINUE;
}
// Default implementation for do_traverse for child class.
int
Type::do_traverse(Traverse*)
{
return TRAVERSE_CONTINUE;
}
// Return whether two types are identical. If ERRORS_ARE_IDENTICAL,
// then return true for all erroneous types; this is used to avoid
// cascading errors. If REASON is not NULL, optionally set *REASON to
// the reason the types are not identical.
bool
Type::are_identical(const Type* t1, const Type* t2, bool errors_are_identical,
std::string* reason)
{
return Type::are_identical_cmp_tags(t1, t2, COMPARE_TAGS,
errors_are_identical, reason);
}
// Like are_identical, but with a CMP_TAGS parameter.
bool
Type::are_identical_cmp_tags(const Type* t1, const Type* t2, Cmp_tags cmp_tags,
bool errors_are_identical, std::string* reason)
{
if (t1 == NULL || t2 == NULL)
{
// Something is wrong.
return errors_are_identical ? true : t1 == t2;
}
// Skip defined forward declarations. Ignore aliases.
t1 = t1->unalias();
t2 = t2->unalias();
if (t1 == t2)
return true;
// An undefined forward declaration is an error.
if (t1->forward_declaration_type() != NULL
|| t2->forward_declaration_type() != NULL)
return errors_are_identical;
// Avoid cascading errors with error types.
if (t1->is_error_type() || t2->is_error_type())
{
if (errors_are_identical)
return true;
return t1->is_error_type() && t2->is_error_type();
}
// Get a good reason for the sink type. Note that the sink type on
// the left hand side of an assignment is handled in are_assignable.
if (t1->is_sink_type() || t2->is_sink_type())
{
if (reason != NULL)
*reason = "invalid use of _";
return false;
}
// A named type is only identical to itself.
if (t1->named_type() != NULL || t2->named_type() != NULL)
return false;
// Check type shapes.
if (t1->classification() != t2->classification())
return false;
switch (t1->classification())
{
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_STRING:
case TYPE_NIL:
// These types are always identical.
return true;
case TYPE_INTEGER:
return t1->integer_type()->is_identical(t2->integer_type());
case TYPE_FLOAT:
return t1->float_type()->is_identical(t2->float_type());
case TYPE_COMPLEX:
return t1->complex_type()->is_identical(t2->complex_type());
case TYPE_FUNCTION:
return t1->function_type()->is_identical(t2->function_type(),
false,
cmp_tags,
errors_are_identical,
reason);
case TYPE_POINTER:
return Type::are_identical_cmp_tags(t1->points_to(), t2->points_to(),
cmp_tags, errors_are_identical,
reason);
case TYPE_STRUCT:
return t1->struct_type()->is_identical(t2->struct_type(), cmp_tags,
errors_are_identical);
case TYPE_ARRAY:
return t1->array_type()->is_identical(t2->array_type(), cmp_tags,
errors_are_identical);
case TYPE_MAP:
return t1->map_type()->is_identical(t2->map_type(), cmp_tags,
errors_are_identical);
case TYPE_CHANNEL:
return t1->channel_type()->is_identical(t2->channel_type(), cmp_tags,
errors_are_identical);
case TYPE_INTERFACE:
return t1->interface_type()->is_identical(t2->interface_type(), cmp_tags,
errors_are_identical);
case TYPE_CALL_MULTIPLE_RESULT:
if (reason != NULL)
*reason = "invalid use of multiple-value function call";
return false;
default:
go_unreachable();
}
}
// Return true if it's OK to have a binary operation with types LHS
// and RHS. This is not used for shifts or comparisons.
bool
Type::are_compatible_for_binop(const Type* lhs, const Type* rhs)
{
if (Type::are_identical(lhs, rhs, true, NULL))
return true;
// A constant of abstract bool type may be mixed with any bool type.
if ((rhs->is_abstract_boolean_type() && lhs->is_boolean_type())
|| (lhs->is_abstract_boolean_type() && rhs->is_boolean_type()))
return true;
// A constant of abstract string type may be mixed with any string
// type.
if ((rhs->is_abstract_string_type() && lhs->is_string_type())
|| (lhs->is_abstract_string_type() && rhs->is_string_type()))
return true;
lhs = lhs->base();
rhs = rhs->base();
// A constant of abstract integer, float, or complex type may be
// mixed with an integer, float, or complex type.
if ((rhs->is_abstract()
&& (rhs->integer_type() != NULL
|| rhs->float_type() != NULL
|| rhs->complex_type() != NULL)
&& (lhs->integer_type() != NULL
|| lhs->float_type() != NULL
|| lhs->complex_type() != NULL))
|| (lhs->is_abstract()
&& (lhs->integer_type() != NULL
|| lhs->float_type() != NULL
|| lhs->complex_type() != NULL)
&& (rhs->integer_type() != NULL
|| rhs->float_type() != NULL
|| rhs->complex_type() != NULL)))
return true;
// The nil type may be compared to a pointer, an interface type, a
// slice type, a channel type, a map type, or a function type.
if (lhs->is_nil_type()
&& (rhs->points_to() != NULL
|| rhs->interface_type() != NULL
|| rhs->is_slice_type()
|| rhs->map_type() != NULL
|| rhs->channel_type() != NULL
|| rhs->function_type() != NULL))
return true;
if (rhs->is_nil_type()
&& (lhs->points_to() != NULL
|| lhs->interface_type() != NULL
|| lhs->is_slice_type()
|| lhs->map_type() != NULL
|| lhs->channel_type() != NULL
|| lhs->function_type() != NULL))
return true;
return false;
}
// Return true if a value with type T1 may be compared with a value of
// type T2. IS_EQUALITY_OP is true for == or !=, false for <, etc.
bool
Type::are_compatible_for_comparison(bool is_equality_op, const Type *t1,
const Type *t2, std::string *reason)
{
if (t1 != t2
&& !Type::are_assignable(t1, t2, NULL)
&& !Type::are_assignable(t2, t1, NULL))
{
if (reason != NULL)
*reason = "incompatible types in binary expression";
return false;
}
if (!is_equality_op)
{
if (t1->integer_type() == NULL
&& t1->float_type() == NULL
&& !t1->is_string_type())
{
if (reason != NULL)
*reason = _("invalid comparison of non-ordered type");
return false;
}
}
else if (t1->is_slice_type()
|| t1->map_type() != NULL
|| t1->function_type() != NULL
|| t2->is_slice_type()
|| t2->map_type() != NULL
|| t2->function_type() != NULL)
{
if (!t1->is_nil_type() && !t2->is_nil_type())
{
if (reason != NULL)
{
if (t1->is_slice_type() || t2->is_slice_type())
*reason = _("slice can only be compared to nil");
else if (t1->map_type() != NULL || t2->map_type() != NULL)
*reason = _("map can only be compared to nil");
else
*reason = _("func can only be compared to nil");
// Match 6g error messages.
if (t1->interface_type() != NULL || t2->interface_type() != NULL)
{
char buf[200];
snprintf(buf, sizeof buf, _("invalid operation (%s)"),
reason->c_str());
*reason = buf;
}
}
return false;
}
}
else
{
if (!t1->is_boolean_type()
&& t1->integer_type() == NULL
&& t1->float_type() == NULL
&& t1->complex_type() == NULL
&& !t1->is_string_type()
&& t1->points_to() == NULL
&& t1->channel_type() == NULL
&& t1->interface_type() == NULL
&& t1->struct_type() == NULL
&& t1->array_type() == NULL
&& !t1->is_nil_type())
{
if (reason != NULL)
*reason = _("invalid comparison of non-comparable type");
return false;
}
if (t1->unalias()->named_type() != NULL)
return t1->unalias()->named_type()->named_type_is_comparable(reason);
else if (t2->unalias()->named_type() != NULL)
return t2->unalias()->named_type()->named_type_is_comparable(reason);
else if (t1->struct_type() != NULL)
{
if (t1->struct_type()->is_struct_incomparable())
{
if (reason != NULL)
*reason = _("invalid comparison of generated struct");
return false;
}
const Struct_field_list* fields = t1->struct_type()->fields();
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
if (!p->type()->is_comparable())
{
if (reason != NULL)
*reason = _("invalid comparison of non-comparable struct");
return false;
}
}
}
else if (t1->array_type() != NULL)
{
if (t1->array_type()->is_array_incomparable())
{
if (reason != NULL)
*reason = _("invalid comparison of generated array");
return false;
}
if (t1->array_type()->length()->is_nil_expression()
|| !t1->array_type()->element_type()->is_comparable())
{
if (reason != NULL)
*reason = _("invalid comparison of non-comparable array");
return false;
}
}
}
return true;
}
// Return true if a value with type RHS may be assigned to a variable
// with type LHS. If REASON is not NULL, set *REASON to the reason
// the types are not assignable.
bool
Type::are_assignable(const Type* lhs, const Type* rhs, std::string* reason)
{
// Do some checks first. Make sure the types are defined.
if (rhs != NULL && !rhs->is_undefined())
{
if (rhs->is_void_type())
{
if (reason != NULL)
*reason = "non-value used as value";
return false;
}
if (rhs->is_call_multiple_result_type())
{
if (reason != NULL)
reason->assign(_("multiple-value function call in "
"single-value context"));
return false;
}
}
// Any value may be assigned to the blank identifier.
if (lhs != NULL
&& !lhs->is_undefined()
&& lhs->is_sink_type())
return true;
// Identical types are assignable.
if (Type::are_identical(lhs, rhs, true, reason))
return true;
// Ignore aliases, except for error messages.
const Type* lhs_orig = lhs;
const Type* rhs_orig = rhs;
lhs = lhs->unalias();
rhs = rhs->unalias();
// The types are assignable if they have identical underlying types
// and either LHS or RHS is not a named type.
if (((lhs->named_type() != NULL && rhs->named_type() == NULL)
|| (rhs->named_type() != NULL && lhs->named_type() == NULL))
&& Type::are_identical(lhs->base(), rhs->base(), true, reason))
return true;
// The types are assignable if LHS is an interface type and RHS
// implements the required methods.
const Interface_type* lhs_interface_type = lhs->interface_type();
if (lhs_interface_type != NULL)
{
if (lhs_interface_type->implements_interface(rhs, reason))
return true;
const Interface_type* rhs_interface_type = rhs->interface_type();
if (rhs_interface_type != NULL
&& lhs_interface_type->is_compatible_for_assign(rhs_interface_type,
reason))
return true;
}
// The type are assignable if RHS is a bidirectional channel type,
// LHS is a channel type, they have identical element types, and
// either LHS or RHS is not a named type.
if (lhs->channel_type() != NULL
&& rhs->channel_type() != NULL
&& rhs->channel_type()->may_send()
&& rhs->channel_type()->may_receive()
&& (lhs->named_type() == NULL || rhs->named_type() == NULL)
&& Type::are_identical(lhs->channel_type()->element_type(),
rhs->channel_type()->element_type(),
true,
reason))
return true;
// The nil type may be assigned to a pointer, function, slice, map,
// channel, or interface type.
if (rhs->is_nil_type()
&& (lhs->points_to() != NULL
|| lhs->function_type() != NULL
|| lhs->is_slice_type()
|| lhs->map_type() != NULL
|| lhs->channel_type() != NULL
|| lhs->interface_type() != NULL))
return true;
// An untyped numeric constant may be assigned to a numeric type if
// it is representable in that type.
if ((rhs->is_abstract()
&& (rhs->integer_type() != NULL
|| rhs->float_type() != NULL
|| rhs->complex_type() != NULL))
&& (lhs->integer_type() != NULL
|| lhs->float_type() != NULL
|| lhs->complex_type() != NULL))
return true;
// Give some better error messages.
if (reason != NULL && reason->empty())
{
if (rhs->interface_type() != NULL)
reason->assign(_("need explicit conversion"));
else if (lhs_orig->named_type() != NULL
&& rhs_orig->named_type() != NULL)
{
size_t len = (lhs_orig->named_type()->name().length()
+ rhs_orig->named_type()->name().length()
+ 100);
char* buf = new char[len];
snprintf(buf, len, _("cannot use type %s as type %s"),
rhs_orig->named_type()->message_name().c_str(),
lhs_orig->named_type()->message_name().c_str());
reason->assign(buf);
delete[] buf;
}
}
return false;
}
// Return true if a value with type RHS may be converted to type LHS.
// If REASON is not NULL, set *REASON to the reason the types are not
// convertible.
bool
Type::are_convertible(const Type* lhs, const Type* rhs, std::string* reason)
{
// The types are convertible if they are assignable.
if (Type::are_assignable(lhs, rhs, reason))
return true;
// Ignore aliases.
lhs = lhs->unalias();
rhs = rhs->unalias();
// A pointer to a regular type may not be converted to a pointer to
// a type that may not live in the heap, except when converting from
// unsafe.Pointer.
if (lhs->points_to() != NULL
&& rhs->points_to() != NULL
&& !lhs->points_to()->in_heap()
&& rhs->points_to()->in_heap()
&& !rhs->is_unsafe_pointer_type())
{
if (reason != NULL)
reason->assign(_("conversion from normal type to notinheap type"));
return false;
}
// The types are convertible if they have identical underlying
// types, ignoring struct field tags.
if ((lhs->named_type() != NULL || rhs->named_type() != NULL)
&& Type::are_identical_cmp_tags(lhs->base(), rhs->base(), IGNORE_TAGS,
true, reason))
return true;
// The types are convertible if they are both unnamed pointer types
// and their pointer base types have identical underlying types,
// ignoring struct field tags.
if (lhs->named_type() == NULL
&& rhs->named_type() == NULL
&& lhs->points_to() != NULL
&& rhs->points_to() != NULL
&& (lhs->points_to()->named_type() != NULL
|| rhs->points_to()->named_type() != NULL)
&& Type::are_identical_cmp_tags(lhs->points_to()->base(),
rhs->points_to()->base(),
IGNORE_TAGS,
true,
reason))
return true;
// Integer and floating point types are convertible to each other.
if ((lhs->integer_type() != NULL || lhs->float_type() != NULL)
&& (rhs->integer_type() != NULL || rhs->float_type() != NULL))
return true;
// Complex types are convertible to each other.
if (lhs->complex_type() != NULL && rhs->complex_type() != NULL)
return true;
// An integer, or []byte, or []rune, may be converted to a string.
if (lhs->is_string_type())
{
if (rhs->integer_type() != NULL)
return true;
if (rhs->is_slice_type())
{
const Type* e = rhs->array_type()->element_type()->forwarded();
if (e->integer_type() != NULL
&& (e->integer_type()->is_byte()
|| e->integer_type()->is_rune()))
return true;
}
}
// A string may be converted to []byte or []rune.
if (rhs->is_string_type() && lhs->is_slice_type())
{
const Type* e = lhs->array_type()->element_type()->forwarded();
if (e->integer_type() != NULL
&& (e->integer_type()->is_byte() || e->integer_type()->is_rune()))
return true;
}
// An unsafe.Pointer type may be converted to any pointer type or to
// a type whose underlying type is uintptr, and vice-versa.
if (lhs->is_unsafe_pointer_type()
&& (rhs->points_to() != NULL
|| (rhs->integer_type() != NULL
&& rhs->integer_type() == Type::lookup_integer_type("uintptr")->real_type())))
return true;
if (rhs->is_unsafe_pointer_type()
&& (lhs->points_to() != NULL
|| (lhs->integer_type() != NULL
&& lhs->integer_type() == Type::lookup_integer_type("uintptr")->real_type())))
return true;
// Give a better error message.
if (reason != NULL)
{
if (reason->empty())
*reason = "invalid type conversion";
else
{
std::string s = "invalid type conversion (";
s += *reason;
s += ')';
*reason = s;
}
}
return false;
}
// Copy expressions if it may change the size.
//
// The only type that has an expression is an array type. The only
// types whose size can be changed by the size of an array type are an
// array type itself, or a struct type with an array field.
Type*
Type::copy_expressions()
{
// This is run during parsing, so types may not be valid yet.
// We only have to worry about array type literals.
switch (this->classification_)
{
default:
return this;
case TYPE_ARRAY:
{
Array_type* at = this->array_type();
if (at->length() == NULL)
return this;
Expression* len = at->length()->copy();
if (at->length() == len)
return this;
return Type::make_array_type(at->element_type(), len);
}
case TYPE_STRUCT:
{
Struct_type* st = this->struct_type();
const Struct_field_list* sfl = st->fields();
if (sfl == NULL)
return this;
bool changed = false;
Struct_field_list *nsfl = new Struct_field_list();
for (Struct_field_list::const_iterator pf = sfl->begin();
pf != sfl->end();
++pf)
{
Type* ft = pf->type()->copy_expressions();
Struct_field nf(Typed_identifier((pf->is_anonymous()
? ""
: pf->field_name()),
ft,
pf->location()));
if (pf->has_tag())
nf.set_tag(pf->tag());
nsfl->push_back(nf);
if (ft != pf->type())
changed = true;
}
if (!changed)
{
delete(nsfl);
return this;
}
return Type::make_struct_type(nsfl, st->location());
}
}
go_unreachable();
}
// Return a hash code for the type to be used for method lookup.
unsigned int
Type::hash_for_method(Gogo* gogo) const
{
if (this->named_type() != NULL && this->named_type()->is_alias())
return this->named_type()->real_type()->hash_for_method(gogo);
unsigned int ret = 0;
if (this->classification_ != TYPE_FORWARD)
ret += this->classification_;
return ret + this->do_hash_for_method(gogo);
}
// Default implementation of do_hash_for_method. This is appropriate
// for types with no subfields.
unsigned int
Type::do_hash_for_method(Gogo*) const
{
return 0;
}
// Return a hash code for a string, given a starting hash.
unsigned int
Type::hash_string(const std::string& s, unsigned int h)
{
const char* p = s.data();
size_t len = s.length();
for (; len > 0; --len)
{
h ^= *p++;
h*= 16777619;
}
return h;
}
// A hash table mapping unnamed types to the backend representation of
// those types.
Type::Type_btypes Type::type_btypes;
// Return the backend representation for this type.
Btype*
Type::get_backend(Gogo* gogo)
{
if (this->btype_ != NULL)
return this->btype_;
if (this->forward_declaration_type() != NULL
|| this->named_type() != NULL)
return this->get_btype_without_hash(gogo);
if (this->is_error_type())
return gogo->backend()->error_type();
// To avoid confusing the backend, translate all identical Go types
// to the same backend representation. We use a hash table to do
// that. There is no need to use the hash table for named types, as
// named types are only identical to themselves.
std::pair<Type*, Type_btype_entry> val;
val.first = this;
val.second.btype = NULL;
val.second.is_placeholder = false;
std::pair<Type_btypes::iterator, bool> ins =
Type::type_btypes.insert(val);
if (!ins.second && ins.first->second.btype != NULL)
{
// Note that GOGO can be NULL here, but only when the GCC
// middle-end is asking for a frontend type. That will only
// happen for simple types, which should never require
// placeholders.
if (!ins.first->second.is_placeholder)
this->btype_ = ins.first->second.btype;
else if (gogo->named_types_are_converted())
{
this->finish_backend(gogo, ins.first->second.btype);
ins.first->second.is_placeholder = false;
}
return ins.first->second.btype;
}
Btype* bt = this->get_btype_without_hash(gogo);
if (ins.first->second.btype == NULL)
{
ins.first->second.btype = bt;
ins.first->second.is_placeholder = false;
}
else
{
// We have already created a backend representation for this
// type. This can happen when an unnamed type is defined using
// a named type which in turns uses an identical unnamed type.
// Use the representation we created earlier and ignore the one we just
// built.
if (this->btype_ == bt)
this->btype_ = ins.first->second.btype;
bt = ins.first->second.btype;
}
return bt;
}
// Return the backend representation for a type without looking in the
// hash table for identical types. This is used for named types,
// since a named type is never identical to any other type.
Btype*
Type::get_btype_without_hash(Gogo* gogo)
{
if (this->btype_ == NULL)
{
Btype* bt = this->do_get_backend(gogo);
// For a recursive function or pointer type, we will temporarily
// return a circular pointer type during the recursion. We
// don't want to record that for a forwarding type, as it may
// confuse us later.
if (this->forward_declaration_type() != NULL
&& gogo->backend()->is_circular_pointer_type(bt))
return bt;
if (gogo == NULL || !gogo->named_types_are_converted())
return bt;
this->btype_ = bt;
}
return this->btype_;
}
// Get the backend representation of a type without forcing the
// creation of the backend representation of all supporting types.
// This will return a backend type that has the correct size but may
// be incomplete. E.g., a pointer will just be a placeholder pointer,
// and will not contain the final representation of the type to which
// it points. This is used while converting all named types to the
// backend representation, to avoid problems with indirect references
// to types which are not yet complete. When this is called, the
// sizes of all direct references (e.g., a struct field) should be
// known, but the sizes of indirect references (e.g., the type to
// which a pointer points) may not.
Btype*
Type::get_backend_placeholder(Gogo* gogo)
{
if (gogo->named_types_are_converted())
return this->get_backend(gogo);
if (this->btype_ != NULL)
return this->btype_;
Btype* bt;
switch (this->classification_)
{
case TYPE_ERROR:
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_NIL:
// These are simple types that can just be created directly.
return this->get_backend(gogo);
case TYPE_MAP:
case TYPE_CHANNEL:
// All maps and channels have the same backend representation.
return this->get_backend(gogo);
case TYPE_NAMED:
case TYPE_FORWARD:
// Named types keep track of their own dependencies and manage
// their own placeholders.
return this->get_backend(gogo);
case TYPE_INTERFACE:
if (this->interface_type()->is_empty())
return Interface_type::get_backend_empty_interface_type(gogo);
break;
default:
break;
}
std::pair<Type*, Type_btype_entry> val;
val.first = this;
val.second.btype = NULL;
val.second.is_placeholder = false;
std::pair<Type_btypes::iterator, bool> ins =
Type::type_btypes.insert(val);
if (!ins.second && ins.first->second.btype != NULL)
return ins.first->second.btype;
switch (this->classification_)
{
case TYPE_FUNCTION:
{
// A Go function type is a pointer to a struct type.
Location loc = this->function_type()->location();
bt = gogo->backend()->placeholder_pointer_type("", loc, false);
}
break;
case TYPE_POINTER:
{
Location loc = Linemap::unknown_location();
bt = gogo->backend()->placeholder_pointer_type("", loc, false);
Pointer_type* pt = this->convert<Pointer_type, TYPE_POINTER>();
Type::placeholder_pointers.push_back(pt);
}
break;
case TYPE_STRUCT:
// We don't have to make the struct itself be a placeholder. We
// are promised that we know the sizes of the struct fields.
// But we may have to use a placeholder for any particular
// struct field.
{
std::vector<Backend::Btyped_identifier> bfields;
get_backend_struct_fields(gogo, this->struct_type()->fields(),
true, &bfields);
bt = gogo->backend()->struct_type(bfields);
}
break;
case TYPE_ARRAY:
if (this->is_slice_type())
{
std::vector<Backend::Btyped_identifier> bfields;
get_backend_slice_fields(gogo, this->array_type(), true, &bfields);
bt = gogo->backend()->struct_type(bfields);
}
else
{
Btype* element = this->array_type()->get_backend_element(gogo, true);
Bexpression* len = this->array_type()->get_backend_length(gogo);
bt = gogo->backend()->array_type(element, len);
}
break;
case TYPE_INTERFACE:
{
go_assert(!this->interface_type()->is_empty());
std::vector<Backend::Btyped_identifier> bfields;
get_backend_interface_fields(gogo, this->interface_type(), true,
&bfields);
bt = gogo->backend()->struct_type(bfields);
}
break;
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
/* Note that various classifications were handled in the earlier
switch. */
default:
go_unreachable();
}
if (ins.first->second.btype == NULL)
{
ins.first->second.btype = bt;
ins.first->second.is_placeholder = true;
}
else
{
// A placeholder for this type got created along the way. Use
// that one and ignore the one we just built.
bt = ins.first->second.btype;
}
return bt;
}
// Complete the backend representation. This is called for a type
// using a placeholder type.
void
Type::finish_backend(Gogo* gogo, Btype *placeholder)
{
switch (this->classification_)
{
case TYPE_ERROR:
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_NIL:
go_unreachable();
case TYPE_FUNCTION:
{
Btype* bt = this->do_get_backend(gogo);
if (!gogo->backend()->set_placeholder_pointer_type(placeholder, bt))
go_assert(saw_errors());
}
break;
case TYPE_POINTER:
{
Btype* bt = this->do_get_backend(gogo);
if (!gogo->backend()->set_placeholder_pointer_type(placeholder, bt))
go_assert(saw_errors());
}
break;
case TYPE_STRUCT:
// The struct type itself is done, but we have to make sure that
// all the field types are converted.
this->struct_type()->finish_backend_fields(gogo);
break;
case TYPE_ARRAY:
// The array type itself is done, but make sure the element type
// is converted.
this->array_type()->finish_backend_element(gogo);
break;
case TYPE_MAP:
case TYPE_CHANNEL:
go_unreachable();
case TYPE_INTERFACE:
// The interface type itself is done, but make sure the method
// types are converted.
this->interface_type()->finish_backend_methods(gogo);
break;
case TYPE_NAMED:
case TYPE_FORWARD:
go_unreachable();
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
default:
go_unreachable();
}
this->btype_ = placeholder;
}
// Return a pointer to the type descriptor for this type.
Bexpression*
Type::type_descriptor_pointer(Gogo* gogo, Location location)
{
Type* t = this->unalias();
if (t->type_descriptor_var_ == NULL)
{
t->make_type_descriptor_var(gogo);
go_assert(t->type_descriptor_var_ != NULL);
}
Bexpression* var_expr =
gogo->backend()->var_expression(t->type_descriptor_var_, location);
Bexpression* var_addr =
gogo->backend()->address_expression(var_expr, location);
Type* td_type = Type::make_type_descriptor_type();
Btype* td_btype = td_type->get_backend(gogo);
Btype* ptd_btype = gogo->backend()->pointer_type(td_btype);
return gogo->backend()->convert_expression(ptd_btype, var_addr, location);
}
// A mapping from unnamed types to type descriptor variables.
Type::Type_descriptor_vars Type::type_descriptor_vars;
// Build the type descriptor for this type.
void
Type::make_type_descriptor_var(Gogo* gogo)
{
go_assert(this->type_descriptor_var_ == NULL);
Named_type* nt = this->named_type();
// We can have multiple instances of unnamed types, but we only want
// to emit the type descriptor once. We use a hash table. This is
// not necessary for named types, as they are unique, and we store
// the type descriptor in the type itself.
Bvariable** phash = NULL;
if (nt == NULL)
{
Bvariable* bvnull = NULL;
std::pair<Type_descriptor_vars::iterator, bool> ins =
Type::type_descriptor_vars.insert(std::make_pair(this, bvnull));
if (!ins.second)
{
// We've already built a type descriptor for this type.
this->type_descriptor_var_ = ins.first->second;
return;
}
phash = &ins.first->second;
}
// The type descriptor symbol for the unsafe.Pointer type is defined in
// libgo/go-unsafe-pointer.c, so we just return a reference to that
// symbol if necessary.
if (this->is_unsafe_pointer_type())
{
Location bloc = Linemap::predeclared_location();
Type* td_type = Type::make_type_descriptor_type();
Btype* td_btype = td_type->get_backend(gogo);
std::string name = gogo->type_descriptor_name(this, nt);
std::string asm_name(go_selectively_encode_id(name));
this->type_descriptor_var_ =
gogo->backend()->immutable_struct_reference(name, asm_name,
td_btype,
bloc);
if (phash != NULL)
*phash = this->type_descriptor_var_;
return;
}
std::string var_name = gogo->type_descriptor_name(this, nt);
// Build the contents of the type descriptor.
Expression* initializer = this->do_type_descriptor(gogo, NULL);
Btype* initializer_btype = initializer->type()->get_backend(gogo);
Location loc = nt == NULL ? Linemap::predeclared_location() : nt->location();
const Package* dummy;
if (this->type_descriptor_defined_elsewhere(nt, &dummy))
{
std::string asm_name(go_selectively_encode_id(var_name));
this->type_descriptor_var_ =
gogo->backend()->immutable_struct_reference(var_name, asm_name,
initializer_btype,
loc);
if (phash != NULL)
*phash = this->type_descriptor_var_;
return;
}
// See if this type descriptor can appear in multiple packages.
bool is_common = false;
if (nt != NULL)
{
// We create the descriptor for a builtin type whenever we need
// it.
is_common = nt->is_builtin();
}
else
{
// This is an unnamed type. The descriptor could be defined in
// any package where it is needed, and the linker will pick one
// descriptor to keep.
is_common = true;
}
// We are going to build the type descriptor in this package. We
// must create the variable before we convert the initializer to the
// backend representation, because the initializer may refer to the
// type descriptor of this type. By setting type_descriptor_var_ we
// ensure that type_descriptor_pointer will work if called while
// converting INITIALIZER.
std::string asm_name(go_selectively_encode_id(var_name));
this->type_descriptor_var_ =
gogo->backend()->immutable_struct(var_name, asm_name, false, is_common,
initializer_btype, loc);
if (phash != NULL)
*phash = this->type_descriptor_var_;
Translate_context context(gogo, NULL, NULL, NULL);
context.set_is_const();
Bexpression* binitializer = initializer->get_backend(&context);
gogo->backend()->immutable_struct_set_init(this->type_descriptor_var_,
var_name, false, is_common,
initializer_btype, loc,
binitializer);
}
// Return true if this type descriptor is defined in a different
// package. If this returns true it sets *PACKAGE to the package.
bool
Type::type_descriptor_defined_elsewhere(Named_type* nt,
const Package** package)
{
if (nt != NULL)
{
if (nt->named_object()->package() != NULL)
{
// This is a named type defined in a different package. The
// type descriptor should be defined in that package.
*package = nt->named_object()->package();
return true;
}
}
else
{
if (this->points_to() != NULL
&& this->points_to()->named_type() != NULL
&& this->points_to()->named_type()->named_object()->package() != NULL)
{
// This is an unnamed pointer to a named type defined in a
// different package. The descriptor should be defined in
// that package.
*package = this->points_to()->named_type()->named_object()->package();
return true;
}
}
return false;
}
// Return a composite literal for a type descriptor.
Expression*
Type::type_descriptor(Gogo* gogo, Type* type)
{
return type->do_type_descriptor(gogo, NULL);
}
// Return a composite literal for a type descriptor with a name.
Expression*
Type::named_type_descriptor(Gogo* gogo, Type* type, Named_type* name)
{
go_assert(name != NULL && type->named_type() != name);
return type->do_type_descriptor(gogo, name);
}
// Make a builtin struct type from a list of fields. The fields are
// pairs of a name and a type.
Struct_type*
Type::make_builtin_struct_type(int nfields, ...)
{
va_list ap;
va_start(ap, nfields);
Location bloc = Linemap::predeclared_location();
Struct_field_list* sfl = new Struct_field_list();
for (int i = 0; i < nfields; i++)
{
const char* field_name = va_arg(ap, const char *);
Type* type = va_arg(ap, Type*);
sfl->push_back(Struct_field(Typed_identifier(field_name, type, bloc)));
}
va_end(ap);
Struct_type* ret = Type::make_struct_type(sfl, bloc);
ret->set_is_struct_incomparable();
return ret;
}
// A list of builtin named types.
std::vector<Named_type*> Type::named_builtin_types;
// Make a builtin named type.
Named_type*
Type::make_builtin_named_type(const char* name, Type* type)
{
Location bloc = Linemap::predeclared_location();
Named_object* no = Named_object::make_type(name, NULL, type, bloc);
Named_type* ret = no->type_value();
Type::named_builtin_types.push_back(ret);
return ret;
}
// Convert the named builtin types.
void
Type::convert_builtin_named_types(Gogo* gogo)
{
for (std::vector<Named_type*>::const_iterator p =
Type::named_builtin_types.begin();
p != Type::named_builtin_types.end();
++p)
{
bool r = (*p)->verify();
go_assert(r);
(*p)->convert(gogo);
}
}
// Return the type of a type descriptor. We should really tie this to
// runtime.Type rather than copying it. This must match the struct "_type"
// declared in libgo/go/runtime/type.go.
Type*
Type::make_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Location bloc = Linemap::predeclared_location();
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* pointer_uint8_type = Type::make_pointer_type(uint8_type);
Type* uint32_type = Type::lookup_integer_type("uint32");
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* string_type = Type::lookup_string_type();
Type* pointer_string_type = Type::make_pointer_type(string_type);
// This is an unnamed version of unsafe.Pointer. Perhaps we
// should use the named version instead, although that would
// require us to create the unsafe package if it has not been
// imported. It probably doesn't matter.
Type* void_type = Type::make_void_type();
Type* unsafe_pointer_type = Type::make_pointer_type(void_type);
Typed_identifier_list *params = new Typed_identifier_list();
params->push_back(Typed_identifier("key", unsafe_pointer_type, bloc));
params->push_back(Typed_identifier("seed", uintptr_type, bloc));
Typed_identifier_list* results = new Typed_identifier_list();
results->push_back(Typed_identifier("", uintptr_type, bloc));
Type* hash_fntype = Type::make_function_type(NULL, params, results,
bloc);
params = new Typed_identifier_list();
params->push_back(Typed_identifier("key1", unsafe_pointer_type, bloc));
params->push_back(Typed_identifier("key2", unsafe_pointer_type, bloc));
results = new Typed_identifier_list();
results->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc));
Type* equal_fntype = Type::make_function_type(NULL, params, results,
bloc);
// Forward declaration for the type descriptor type.
Named_object* named_type_descriptor_type =
Named_object::make_type_declaration("_type", NULL, bloc);
Type* ft = Type::make_forward_declaration(named_type_descriptor_type);
Type* pointer_type_descriptor_type = Type::make_pointer_type(ft);
// The type of a method on a concrete type.
Struct_type* method_type =
Type::make_builtin_struct_type(5,
"name", pointer_string_type,
"pkgPath", pointer_string_type,
"mtyp", pointer_type_descriptor_type,
"typ", pointer_type_descriptor_type,
"tfn", unsafe_pointer_type);
Named_type* named_method_type =
Type::make_builtin_named_type("method", method_type);
// Information for types with a name or methods.
Type* slice_named_method_type =
Type::make_array_type(named_method_type, NULL);
Struct_type* uncommon_type =
Type::make_builtin_struct_type(3,
"name", pointer_string_type,
"pkgPath", pointer_string_type,
"methods", slice_named_method_type);
Named_type* named_uncommon_type =
Type::make_builtin_named_type("uncommonType", uncommon_type);
Type* pointer_uncommon_type =
Type::make_pointer_type(named_uncommon_type);
// The type descriptor type.
Struct_type* type_descriptor_type =
Type::make_builtin_struct_type(12,
"size", uintptr_type,
"ptrdata", uintptr_type,
"hash", uint32_type,
"kind", uint8_type,
"align", uint8_type,
"fieldAlign", uint8_type,
"hashfn", hash_fntype,
"equalfn", equal_fntype,
"gcdata", pointer_uint8_type,
"string", pointer_string_type,
"", pointer_uncommon_type,
"ptrToThis",
pointer_type_descriptor_type);
Named_type* named = Type::make_builtin_named_type("_type",
type_descriptor_type);
named_type_descriptor_type->set_type_value(named);
ret = named;
}
return ret;
}
// Make the type of a pointer to a type descriptor as represented in
// Go.
Type*
Type::make_type_descriptor_ptr_type()
{
static Type* ret;
if (ret == NULL)
ret = Type::make_pointer_type(Type::make_type_descriptor_type());
return ret;
}
// Return the alignment required by the memequalN function. N is a
// type size: 16, 32, 64, or 128. The memequalN functions are defined
// in libgo/go/runtime/alg.go.
int64_t
Type::memequal_align(Gogo* gogo, int size)
{
const char* tn;
switch (size)
{
case 16:
tn = "int16";
break;
case 32:
tn = "int32";
break;
case 64:
tn = "int64";
break;
case 128:
// The code uses [2]int64, which must have the same alignment as
// int64.
tn = "int64";
break;
default:
go_unreachable();
}
Type* t = Type::lookup_integer_type(tn);
int64_t ret;
if (!t->backend_type_align(gogo, &ret))
go_unreachable();
return ret;
}
// Return whether this type needs specially built type functions.
// This returns true for types that are comparable and either can not
// use an identity comparison, or are a non-standard size.
bool
Type::needs_specific_type_functions(Gogo* gogo)
{
Named_type* nt = this->named_type();
if (nt != NULL && nt->is_alias())
return false;
if (!this->is_comparable())
return false;
if (!this->compare_is_identity(gogo))
return true;
// We create a few predeclared types for type descriptors; they are
// really just for the backend and don't need hash or equality
// functions.
if (nt != NULL && Linemap::is_predeclared_location(nt->location()))
return false;
int64_t size, align;
if (!this->backend_type_size(gogo, &size)
|| !this->backend_type_align(gogo, &align))
{
go_assert(saw_errors());
return false;
}
// This switch matches the one in Type::type_functions.
switch (size)
{
case 0:
case 1:
case 2:
return align < Type::memequal_align(gogo, 16);
case 4:
return align < Type::memequal_align(gogo, 32);
case 8:
return align < Type::memequal_align(gogo, 64);
case 16:
return align < Type::memequal_align(gogo, 128);
default:
return true;
}
}
// Set *HASH_FN and *EQUAL_FN to the runtime functions which compute a
// hash code for this type and which compare whether two values of
// this type are equal. If NAME is not NULL it is the name of this
// type. HASH_FNTYPE and EQUAL_FNTYPE are the types of these
// functions, for convenience; they may be NULL.
void
Type::type_functions(Gogo* gogo, Named_type* name, Function_type* hash_fntype,
Function_type* equal_fntype, Named_object** hash_fn,
Named_object** equal_fn)
{
// If the unaliased type is not a named type, then the type does not
// have a name after all.
if (name != NULL)
name = name->unalias()->named_type();
if (!this->is_comparable())
{
*hash_fn = NULL;
*equal_fn = NULL;
return;
}
if (hash_fntype == NULL || equal_fntype == NULL)
{
Location bloc = Linemap::predeclared_location();
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* void_type = Type::make_void_type();
Type* unsafe_pointer_type = Type::make_pointer_type(void_type);
if (hash_fntype == NULL)
{
Typed_identifier_list* params = new Typed_identifier_list();
params->push_back(Typed_identifier("key", unsafe_pointer_type,
bloc));
params->push_back(Typed_identifier("seed", uintptr_type, bloc));
Typed_identifier_list* results = new Typed_identifier_list();
results->push_back(Typed_identifier("", uintptr_type, bloc));
hash_fntype = Type::make_function_type(NULL, params, results, bloc);
}
if (equal_fntype == NULL)
{
Typed_identifier_list* params = new Typed_identifier_list();
params->push_back(Typed_identifier("key1", unsafe_pointer_type,
bloc));
params->push_back(Typed_identifier("key2", unsafe_pointer_type,
bloc));
Typed_identifier_list* results = new Typed_identifier_list();
results->push_back(Typed_identifier("", Type::lookup_bool_type(),
bloc));
equal_fntype = Type::make_function_type(NULL, params, results, bloc);
}
}
const char* hash_fnname;
const char* equal_fnname;
if (this->compare_is_identity(gogo))
{
int64_t size, align;
if (!this->backend_type_size(gogo, &size)
|| !this->backend_type_align(gogo, &align))
{
go_assert(saw_errors());
return;
}
bool build_functions = false;
// This switch matches the one in Type::needs_specific_type_functions.
// The alignment tests are because of the memequal functions,
// which assume that the values are aligned as required for an
// integer of that size.
switch (size)
{
case 0:
hash_fnname = "runtime.memhash0";
equal_fnname = "runtime.memequal0";
break;
case 1:
hash_fnname = "runtime.memhash8";
equal_fnname = "runtime.memequal8";
break;
case 2:
if (align < Type::memequal_align(gogo, 16))
build_functions = true;
else
{
hash_fnname = "runtime.memhash16";
equal_fnname = "runtime.memequal16";
}
break;
case 4:
if (align < Type::memequal_align(gogo, 32))
build_functions = true;
else
{
hash_fnname = "runtime.memhash32";
equal_fnname = "runtime.memequal32";
}
break;
case 8:
if (align < Type::memequal_align(gogo, 64))
build_functions = true;
else
{
hash_fnname = "runtime.memhash64";
equal_fnname = "runtime.memequal64";
}
break;
case 16:
if (align < Type::memequal_align(gogo, 128))
build_functions = true;
else
{
hash_fnname = "runtime.memhash128";
equal_fnname = "runtime.memequal128";
}
break;
default:
build_functions = true;
break;
}
if (build_functions)
{
// We don't have a built-in function for a type of this size
// and alignment. Build a function to use that calls the
// generic hash/equality functions for identity, passing the size.
this->specific_type_functions(gogo, name, size, hash_fntype,
equal_fntype, hash_fn, equal_fn);
return;
}
}
else
{
switch (this->base()->classification())
{
case Type::TYPE_ERROR:
case Type::TYPE_VOID:
case Type::TYPE_NIL:
case Type::TYPE_FUNCTION:
case Type::TYPE_MAP:
// For these types is_comparable should have returned false.
go_unreachable();
case Type::TYPE_BOOLEAN:
case Type::TYPE_INTEGER:
case Type::TYPE_POINTER:
case Type::TYPE_CHANNEL:
// For these types compare_is_identity should have returned true.
go_unreachable();
case Type::TYPE_FLOAT:
switch (this->float_type()->bits())
{
case 32:
hash_fnname = "runtime.f32hash";
equal_fnname = "runtime.f32equal";
break;
case 64:
hash_fnname = "runtime.f64hash";
equal_fnname = "runtime.f64equal";
break;
default:
go_unreachable();
}
break;
case Type::TYPE_COMPLEX:
switch (this->complex_type()->bits())
{
case 64:
hash_fnname = "runtime.c64hash";
equal_fnname = "runtime.c64equal";
break;
case 128:
hash_fnname = "runtime.c128hash";
equal_fnname = "runtime.c128equal";
break;
default:
go_unreachable();
}
break;
case Type::TYPE_STRING:
hash_fnname = "runtime.strhash";
equal_fnname = "runtime.strequal";
break;
case Type::TYPE_STRUCT:
{
// This is a struct which can not be compared using a
// simple identity function. We need to build a function
// for comparison.
this->specific_type_functions(gogo, name, -1, hash_fntype,
equal_fntype, hash_fn, equal_fn);
return;
}
case Type::TYPE_ARRAY:
if (this->is_slice_type())
{
// Type::is_compatible_for_comparison should have
// returned false.
go_unreachable();
}
else
{
// This is an array which can not be compared using a
// simple identity function. We need to build a
// function for comparison.
this->specific_type_functions(gogo, name, -1, hash_fntype,
equal_fntype, hash_fn, equal_fn);
return;
}
break;
case Type::TYPE_INTERFACE:
if (this->interface_type()->is_empty())
{
hash_fnname = "runtime.nilinterhash";
equal_fnname = "runtime.nilinterequal";
}
else
{
hash_fnname = "runtime.interhash";
equal_fnname = "runtime.interequal";
}
break;
case Type::TYPE_NAMED:
case Type::TYPE_FORWARD:
go_unreachable();
default:
go_unreachable();
}
}
Location bloc = Linemap::predeclared_location();
*hash_fn = Named_object::make_function_declaration(hash_fnname, NULL,
hash_fntype, bloc);
(*hash_fn)->func_declaration_value()->set_asm_name(hash_fnname);
*equal_fn = Named_object::make_function_declaration(equal_fnname, NULL,
equal_fntype, bloc);
(*equal_fn)->func_declaration_value()->set_asm_name(equal_fnname);
}
// A hash table mapping types to the specific hash functions.
Type::Type_functions Type::type_functions_table;
// Handle a type function which is specific to a type: if SIZE == -1,
// this is a struct or array that can not use an identity comparison.
// Otherwise, it is a type that uses an identity comparison but is not
// one of the standard supported sizes.
void
Type::specific_type_functions(Gogo* gogo, Named_type* name, int64_t size,
Function_type* hash_fntype,
Function_type* equal_fntype,
Named_object** hash_fn,
Named_object** equal_fn)
{
Hash_equal_fn fnull(NULL, NULL);
std::pair<Type*, Hash_equal_fn> val(name != NULL ? name : this, fnull);
std::pair<Type_functions::iterator, bool> ins =
Type::type_functions_table.insert(val);
if (!ins.second)
{
// We already have functions for this type
*hash_fn = ins.first->second.first;
*equal_fn = ins.first->second.second;
return;
}
std::string hash_name;
std::string equal_name;
gogo->specific_type_function_names(this, name, &hash_name, &equal_name);
Location bloc = Linemap::predeclared_location();
const Package* package = NULL;
bool is_defined_elsewhere =
this->type_descriptor_defined_elsewhere(name, &package);
if (is_defined_elsewhere)
{
*hash_fn = Named_object::make_function_declaration(hash_name, package,
hash_fntype, bloc);
*equal_fn = Named_object::make_function_declaration(equal_name, package,
equal_fntype, bloc);
}
else
{
*hash_fn = gogo->declare_package_function(hash_name, hash_fntype, bloc);
*equal_fn = gogo->declare_package_function(equal_name, equal_fntype,
bloc);
}
ins.first->second.first = *hash_fn;
ins.first->second.second = *equal_fn;
if (!is_defined_elsewhere)
{
if (gogo->in_global_scope())
this->write_specific_type_functions(gogo, name, size, hash_name,
hash_fntype, equal_name,
equal_fntype);
else
gogo->queue_specific_type_function(this, name, size, hash_name,
hash_fntype, equal_name,
equal_fntype);
}
}
// Write the hash and equality functions for a type which needs to be
// written specially.
void
Type::write_specific_type_functions(Gogo* gogo, Named_type* name, int64_t size,
const std::string& hash_name,
Function_type* hash_fntype,
const std::string& equal_name,
Function_type* equal_fntype)
{
Location bloc = Linemap::predeclared_location();
if (gogo->specific_type_functions_are_written())
{
go_assert(saw_errors());
return;
}
go_assert(this->is_comparable());
Named_object* hash_fn = gogo->start_function(hash_name, hash_fntype, false,
bloc);
hash_fn->func_value()->set_is_type_specific_function();
gogo->start_block(bloc);
if (size != -1)
this->write_identity_hash(gogo, size);
else if (name != NULL && name->real_type()->named_type() != NULL)
this->write_named_hash(gogo, name, hash_fntype, equal_fntype);
else if (this->struct_type() != NULL)
this->struct_type()->write_hash_function(gogo, name, hash_fntype,
equal_fntype);
else if (this->array_type() != NULL)
this->array_type()->write_hash_function(gogo, name, hash_fntype,
equal_fntype);
else
go_unreachable();
Block* b = gogo->finish_block(bloc);
gogo->add_block(b, bloc);
gogo->lower_block(hash_fn, b);
gogo->finish_function(bloc);
Named_object *equal_fn = gogo->start_function(equal_name, equal_fntype,
false, bloc);
equal_fn->func_value()->set_is_type_specific_function();
gogo->start_block(bloc);
if (size != -1)
this->write_identity_equal(gogo, size);
else if (name != NULL && name->real_type()->named_type() != NULL)
this->write_named_equal(gogo, name);
else if (this->struct_type() != NULL)
this->struct_type()->write_equal_function(gogo, name);
else if (this->array_type() != NULL)
this->array_type()->write_equal_function(gogo, name);
else
go_unreachable();
b = gogo->finish_block(bloc);
gogo->add_block(b, bloc);
gogo->lower_block(equal_fn, b);
gogo->finish_function(bloc);
// Build the function descriptors for the type descriptor to refer to.
hash_fn->func_value()->descriptor(gogo, hash_fn);
equal_fn->func_value()->descriptor(gogo, equal_fn);
}
// Write a hash function for a type that can use an identity hash but
// is not one of the standard supported sizes. For example, this
// would be used for the type [3]byte. This builds a return statement
// that returns a call to the memhash function, passing the key and
// seed from the function arguments (already constructed before this
// is called), and the constant size.
void
Type::write_identity_hash(Gogo* gogo, int64_t size)
{
Location bloc = Linemap::predeclared_location();
Type* unsafe_pointer_type = Type::make_pointer_type(Type::make_void_type());
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Typed_identifier_list* params = new Typed_identifier_list();
params->push_back(Typed_identifier("key", unsafe_pointer_type, bloc));
params->push_back(Typed_identifier("seed", uintptr_type, bloc));
params->push_back(Typed_identifier("size", uintptr_type, bloc));
Typed_identifier_list* results = new Typed_identifier_list();
results->push_back(Typed_identifier("", uintptr_type, bloc));
Function_type* memhash_fntype = Type::make_function_type(NULL, params,
results, bloc);
Named_object* memhash =
Named_object::make_function_declaration("runtime.memhash", NULL,
memhash_fntype, bloc);
memhash->func_declaration_value()->set_asm_name("runtime.memhash");
Named_object* key_arg = gogo->lookup("key", NULL);
go_assert(key_arg != NULL);
Named_object* seed_arg = gogo->lookup("seed", NULL);
go_assert(seed_arg != NULL);
Expression* key_ref = Expression::make_var_reference(key_arg, bloc);
Expression* seed_ref = Expression::make_var_reference(seed_arg, bloc);
Expression* size_arg = Expression::make_integer_int64(size, uintptr_type,
bloc);
Expression_list* args = new Expression_list();
args->push_back(key_ref);
args->push_back(seed_ref);
args->push_back(size_arg);
Expression* func = Expression::make_func_reference(memhash, NULL, bloc);
Expression* call = Expression::make_call(func, args, false, bloc);
Expression_list* vals = new Expression_list();
vals->push_back(call);
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Write an equality function for a type that can use an identity
// equality comparison but is not one of the standard supported sizes.
// For example, this would be used for the type [3]byte. This builds
// a return statement that returns a call to the memequal function,
// passing the two keys from the function arguments (already
// constructed before this is called), and the constant size.
void
Type::write_identity_equal(Gogo* gogo, int64_t size)
{
Location bloc = Linemap::predeclared_location();
Type* unsafe_pointer_type = Type::make_pointer_type(Type::make_void_type());
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Typed_identifier_list* params = new Typed_identifier_list();
params->push_back(Typed_identifier("key1", unsafe_pointer_type, bloc));
params->push_back(Typed_identifier("key2", unsafe_pointer_type, bloc));
params->push_back(Typed_identifier("size", uintptr_type, bloc));
Typed_identifier_list* results = new Typed_identifier_list();
results->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc));
Function_type* memequal_fntype = Type::make_function_type(NULL, params,
results, bloc);
Named_object* memequal =
Named_object::make_function_declaration("runtime.memequal", NULL,
memequal_fntype, bloc);
memequal->func_declaration_value()->set_asm_name("runtime.memequal");
Named_object* key1_arg = gogo->lookup("key1", NULL);
go_assert(key1_arg != NULL);
Named_object* key2_arg = gogo->lookup("key2", NULL);
go_assert(key2_arg != NULL);
Expression* key1_ref = Expression::make_var_reference(key1_arg, bloc);
Expression* key2_ref = Expression::make_var_reference(key2_arg, bloc);
Expression* size_arg = Expression::make_integer_int64(size, uintptr_type,
bloc);
Expression_list* args = new Expression_list();
args->push_back(key1_ref);
args->push_back(key2_ref);
args->push_back(size_arg);
Expression* func = Expression::make_func_reference(memequal, NULL, bloc);
Expression* call = Expression::make_call(func, args, false, bloc);
Expression_list* vals = new Expression_list();
vals->push_back(call);
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Write a hash function that simply calls the hash function for a
// named type. This is used when one named type is defined as
// another. This ensures that this case works when the other named
// type is defined in another package and relies on calling hash
// functions defined only in that package.
void
Type::write_named_hash(Gogo* gogo, Named_type* name,
Function_type* hash_fntype, Function_type* equal_fntype)
{
Location bloc = Linemap::predeclared_location();
Named_type* base_type = name->real_type()->named_type();
while (base_type->is_alias())
{
base_type = base_type->real_type()->named_type();
go_assert(base_type != NULL);
}
go_assert(base_type != NULL);
// The pointer to the type we are going to hash. This is an
// unsafe.Pointer.
Named_object* key_arg = gogo->lookup("key", NULL);
go_assert(key_arg != NULL);
// The seed argument to the hash function.
Named_object* seed_arg = gogo->lookup("seed", NULL);
go_assert(seed_arg != NULL);
Named_object* hash_fn;
Named_object* equal_fn;
name->real_type()->type_functions(gogo, base_type, hash_fntype, equal_fntype,
&hash_fn, &equal_fn);
// Call the hash function for the base type.
Expression* key_ref = Expression::make_var_reference(key_arg, bloc);
Expression* seed_ref = Expression::make_var_reference(seed_arg, bloc);
Expression_list* args = new Expression_list();
args->push_back(key_ref);
args->push_back(seed_ref);
Expression* func = Expression::make_func_reference(hash_fn, NULL, bloc);
Expression* call = Expression::make_call(func, args, false, bloc);
// Return the hash of the base type.
Expression_list* vals = new Expression_list();
vals->push_back(call);
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Write an equality function that simply calls the equality function
// for a named type. This is used when one named type is defined as
// another. This ensures that this case works when the other named
// type is defined in another package and relies on calling equality
// functions defined only in that package.
void
Type::write_named_equal(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
// The pointers to the types we are going to compare. These have
// type unsafe.Pointer.
Named_object* key1_arg = gogo->lookup("key1", NULL);
Named_object* key2_arg = gogo->lookup("key2", NULL);
go_assert(key1_arg != NULL && key2_arg != NULL);
Named_type* base_type = name->real_type()->named_type();
go_assert(base_type != NULL);
// Build temporaries with the base type.
Type* pt = Type::make_pointer_type(base_type);
Expression* ref = Expression::make_var_reference(key1_arg, bloc);
ref = Expression::make_cast(pt, ref, bloc);
Temporary_statement* p1 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p1);
ref = Expression::make_var_reference(key2_arg, bloc);
ref = Expression::make_cast(pt, ref, bloc);
Temporary_statement* p2 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p2);
// Compare the values for equality.
Expression* t1 = Expression::make_temporary_reference(p1, bloc);
t1 = Expression::make_dereference(t1, Expression::NIL_CHECK_NOT_NEEDED, bloc);
Expression* t2 = Expression::make_temporary_reference(p2, bloc);
t2 = Expression::make_dereference(t2, Expression::NIL_CHECK_NOT_NEEDED, bloc);
Expression* cond = Expression::make_binary(OPERATOR_EQEQ, t1, t2, bloc);
// Return the equality comparison.
Expression_list* vals = new Expression_list();
vals->push_back(cond);
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Return a composite literal for the type descriptor for a plain type
// of kind RUNTIME_TYPE_KIND named NAME.
Expression*
Type::type_descriptor_constructor(Gogo* gogo, int runtime_type_kind,
Named_type* name, const Methods* methods,
bool only_value_methods)
{
Location bloc = Linemap::predeclared_location();
Type* td_type = Type::make_type_descriptor_type();
const Struct_field_list* fields = td_type->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(12);
if (!this->has_pointer())
runtime_type_kind |= RUNTIME_TYPE_KIND_NO_POINTERS;
if (this->points_to() != NULL)
runtime_type_kind |= RUNTIME_TYPE_KIND_DIRECT_IFACE;
int64_t ptrsize;
int64_t ptrdata;
if (this->needs_gcprog(gogo, &ptrsize, &ptrdata))
runtime_type_kind |= RUNTIME_TYPE_KIND_GC_PROG;
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("size"));
Expression::Type_info type_info = Expression::TYPE_INFO_SIZE;
vals->push_back(Expression::make_type_info(this, type_info));
++p;
go_assert(p->is_field_name("ptrdata"));
type_info = Expression::TYPE_INFO_DESCRIPTOR_PTRDATA;
vals->push_back(Expression::make_type_info(this, type_info));
++p;
go_assert(p->is_field_name("hash"));
unsigned int h;
if (name != NULL)
h = name->hash_for_method(gogo);
else
h = this->hash_for_method(gogo);
vals->push_back(Expression::make_integer_ul(h, p->type(), bloc));
++p;
go_assert(p->is_field_name("kind"));
vals->push_back(Expression::make_integer_ul(runtime_type_kind, p->type(),
bloc));
++p;
go_assert(p->is_field_name("align"));
type_info = Expression::TYPE_INFO_ALIGNMENT;
vals->push_back(Expression::make_type_info(this, type_info));
++p;
go_assert(p->is_field_name("fieldAlign"));
type_info = Expression::TYPE_INFO_FIELD_ALIGNMENT;
vals->push_back(Expression::make_type_info(this, type_info));
++p;
go_assert(p->is_field_name("hashfn"));
Function_type* hash_fntype = p->type()->function_type();
++p;
go_assert(p->is_field_name("equalfn"));
Function_type* equal_fntype = p->type()->function_type();
Named_object* hash_fn;
Named_object* equal_fn;
this->type_functions(gogo, name, hash_fntype, equal_fntype, &hash_fn,
&equal_fn);
if (hash_fn == NULL)
vals->push_back(Expression::make_cast(hash_fntype,
Expression::make_nil(bloc),
bloc));
else
vals->push_back(Expression::make_func_reference(hash_fn, NULL, bloc));
if (equal_fn == NULL)
vals->push_back(Expression::make_cast(equal_fntype,
Expression::make_nil(bloc),
bloc));
else
vals->push_back(Expression::make_func_reference(equal_fn, NULL, bloc));
++p;
go_assert(p->is_field_name("gcdata"));
vals->push_back(Expression::make_gc_symbol(this));
++p;
go_assert(p->is_field_name("string"));
Expression* s = Expression::make_string((name != NULL
? name->reflection(gogo)
: this->reflection(gogo)),
bloc);
vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
++p;
go_assert(p->is_field_name("uncommonType"));
if (name == NULL && methods == NULL)
vals->push_back(Expression::make_nil(bloc));
else
{
if (methods == NULL)
methods = name->methods();
vals->push_back(this->uncommon_type_constructor(gogo,
p->type()->deref(),
name, methods,
only_value_methods));
}
++p;
go_assert(p->is_field_name("ptrToThis"));
if (name == NULL && methods == NULL)
vals->push_back(Expression::make_nil(bloc));
else
{
Type* pt;
if (name != NULL)
pt = Type::make_pointer_type(name);
else
pt = Type::make_pointer_type(this);
vals->push_back(Expression::make_type_descriptor(pt, bloc));
}
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(td_type, vals, bloc);
}
// The maximum length of a GC ptrmask bitmap. This corresponds to the
// length used by the gc toolchain, and also appears in
// libgo/go/reflect/type.go.
static const int64_t max_ptrmask_bytes = 2048;
// Return a pointer to the Garbage Collection information for this type.
Bexpression*
Type::gc_symbol_pointer(Gogo* gogo)
{
Type* t = this->unalias();
if (!t->has_pointer())
return gogo->backend()->nil_pointer_expression();
if (t->gc_symbol_var_ == NULL)
{
t->make_gc_symbol_var(gogo);
go_assert(t->gc_symbol_var_ != NULL);
}
Location bloc = Linemap::predeclared_location();
Bexpression* var_expr =
gogo->backend()->var_expression(t->gc_symbol_var_, bloc);
Bexpression* addr_expr =
gogo->backend()->address_expression(var_expr, bloc);
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* pointer_uint8_type = Type::make_pointer_type(uint8_type);
Btype* ubtype = pointer_uint8_type->get_backend(gogo);
return gogo->backend()->convert_expression(ubtype, addr_expr, bloc);
}
// A mapping from unnamed types to GC symbol variables.
Type::GC_symbol_vars Type::gc_symbol_vars;
// Build the GC symbol for this type.
void
Type::make_gc_symbol_var(Gogo* gogo)
{
go_assert(this->gc_symbol_var_ == NULL);
Named_type* nt = this->named_type();
// We can have multiple instances of unnamed types and similar to type
// descriptors, we only want to the emit the GC data once, so we use a
// hash table.
Bvariable** phash = NULL;
if (nt == NULL)
{
Bvariable* bvnull = NULL;
std::pair<GC_symbol_vars::iterator, bool> ins =
Type::gc_symbol_vars.insert(std::make_pair(this, bvnull));
if (!ins.second)
{
// We've already built a gc symbol for this type.
this->gc_symbol_var_ = ins.first->second;
return;
}
phash = &ins.first->second;
}
int64_t ptrsize;
int64_t ptrdata;
if (!this->needs_gcprog(gogo, &ptrsize, &ptrdata))
{
this->gc_symbol_var_ = this->gc_ptrmask_var(gogo, ptrsize, ptrdata);
if (phash != NULL)
*phash = this->gc_symbol_var_;
return;
}
std::string sym_name = gogo->gc_symbol_name(this);
// Build the contents of the gc symbol.
Expression* sym_init = this->gcprog_constructor(gogo, ptrsize, ptrdata);
Btype* sym_btype = sym_init->type()->get_backend(gogo);
// If the type descriptor for this type is defined somewhere else, so is the
// GC symbol.
const Package* dummy;
if (this->type_descriptor_defined_elsewhere(nt, &dummy))
{
std::string asm_name(go_selectively_encode_id(sym_name));
this->gc_symbol_var_ =
gogo->backend()->implicit_variable_reference(sym_name, asm_name,
sym_btype);
if (phash != NULL)
*phash = this->gc_symbol_var_;
return;
}
// See if this gc symbol can appear in multiple packages.
bool is_common = false;
if (nt != NULL)
{
// We create the symbol for a builtin type whenever we need
// it.
is_common = nt->is_builtin();
}
else
{
// This is an unnamed type. The descriptor could be defined in
// any package where it is needed, and the linker will pick one
// descriptor to keep.
is_common = true;
}
// Since we are building the GC symbol in this package, we must create the
// variable before converting the initializer to its backend representation
// because the initializer may refer to the GC symbol for this type.
std::string asm_name(go_selectively_encode_id(sym_name));
this->gc_symbol_var_ =
gogo->backend()->implicit_variable(sym_name, asm_name,
sym_btype, false, true, is_common, 0);
if (phash != NULL)
*phash = this->gc_symbol_var_;
Translate_context context(gogo, NULL, NULL, NULL);
context.set_is_const();
Bexpression* sym_binit = sym_init->get_backend(&context);
gogo->backend()->implicit_variable_set_init(this->gc_symbol_var_, sym_name,
sym_btype, false, true, is_common,
sym_binit);
}
// Return whether this type needs a GC program, and set *PTRDATA to
// the size of the pointer data in bytes and *PTRSIZE to the size of a
// pointer.
bool
Type::needs_gcprog(Gogo* gogo, int64_t* ptrsize, int64_t* ptrdata)
{
Type* voidptr = Type::make_pointer_type(Type::make_void_type());
if (!voidptr->backend_type_size(gogo, ptrsize))
go_unreachable();
if (!this->backend_type_ptrdata(gogo, ptrdata))
{
go_assert(saw_errors());
return false;
}
return *ptrdata / *ptrsize > max_ptrmask_bytes;
}
// A simple class used to build a GC ptrmask for a type.
class Ptrmask
{
public:
Ptrmask(size_t count)
: bits_((count + 7) / 8, 0)
{}
void
set_from(Gogo*, Type*, int64_t ptrsize, int64_t offset);
std::string
symname() const;
Expression*
constructor(Gogo* gogo) const;
private:
void
set(size_t index)
{ this->bits_.at(index / 8) |= 1 << (index % 8); }
// The actual bits.
std::vector<unsigned char> bits_;
};
// Set bits in ptrmask starting from OFFSET based on TYPE. OFFSET
// counts in bytes. PTRSIZE is the size of a pointer on the target
// system.
void
Ptrmask::set_from(Gogo* gogo, Type* type, int64_t ptrsize, int64_t offset)
{
switch (type->base()->classification())
{
default:
case Type::TYPE_NIL:
case Type::TYPE_CALL_MULTIPLE_RESULT:
case Type::TYPE_NAMED:
case Type::TYPE_FORWARD:
go_unreachable();
case Type::TYPE_ERROR:
case Type::TYPE_VOID:
case Type::TYPE_BOOLEAN:
case Type::TYPE_INTEGER:
case Type::TYPE_FLOAT:
case Type::TYPE_COMPLEX:
case Type::TYPE_SINK:
break;
case Type::TYPE_FUNCTION:
case Type::TYPE_POINTER:
case Type::TYPE_MAP:
case Type::TYPE_CHANNEL:
// These types are all a single pointer.
go_assert((offset % ptrsize) == 0);
this->set(offset / ptrsize);
break;
case Type::TYPE_STRING:
// A string starts with a single pointer.
go_assert((offset % ptrsize) == 0);
this->set(offset / ptrsize);
break;
case Type::TYPE_INTERFACE:
// An interface is two pointers.
go_assert((offset % ptrsize) == 0);
this->set(offset / ptrsize);
this->set((offset / ptrsize) + 1);
break;
case Type::TYPE_STRUCT:
{
if (!type->has_pointer())
return;
const Struct_field_list* fields = type->struct_type()->fields();
int64_t soffset = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
int64_t field_align;
if (!pf->type()->backend_type_field_align(gogo, &field_align))
{
go_assert(saw_errors());
return;
}
soffset = (soffset + (field_align - 1)) &~ (field_align - 1);
this->set_from(gogo, pf->type(), ptrsize, offset + soffset);
int64_t field_size;
if (!pf->type()->backend_type_size(gogo, &field_size))
{
go_assert(saw_errors());
return;
}
soffset += field_size;
}
}
break;
case Type::TYPE_ARRAY:
if (type->is_slice_type())
{
// A slice starts with a single pointer.
go_assert((offset % ptrsize) == 0);
this->set(offset / ptrsize);
break;
}
else
{
if (!type->has_pointer())
return;
int64_t len;
if (!type->array_type()->int_length(&len))
{
go_assert(saw_errors());
return;
}
Type* element_type = type->array_type()->element_type();
int64_t ele_size;
if (!element_type->backend_type_size(gogo, &ele_size))
{
go_assert(saw_errors());
return;
}
int64_t eoffset = 0;
for (int64_t i = 0; i < len; i++, eoffset += ele_size)
this->set_from(gogo, element_type, ptrsize, offset + eoffset);
break;
}
}
}
// Return a symbol name for this ptrmask. This is used to coalesce
// identical ptrmasks, which are common. The symbol name must use
// only characters that are valid in symbols. It's nice if it's
// short. We convert it to a string that uses only 32 characters,
// avoiding digits and u and U.
std::string
Ptrmask::symname() const
{
const char chars[33] = "abcdefghijklmnopqrstvwxyzABCDEFG";
go_assert(chars[32] == '\0');
std::string ret;
unsigned int b = 0;
int remaining = 0;
for (std::vector<unsigned char>::const_iterator p = this->bits_.begin();
p != this->bits_.end();
++p)
{
b |= *p << remaining;
remaining += 8;
while (remaining >= 5)
{
ret += chars[b & 0x1f];
b >>= 5;
remaining -= 5;
}
}
while (remaining > 0)
{
ret += chars[b & 0x1f];
b >>= 5;
remaining -= 5;
}
return ret;
}
// Return a constructor for this ptrmask. This will be used to
// initialize the runtime ptrmask value.
Expression*
Ptrmask::constructor(Gogo* gogo) const
{
Location bloc = Linemap::predeclared_location();
Type* byte_type = gogo->lookup_global("byte")->type_value();
Expression* len = Expression::make_integer_ul(this->bits_.size(), NULL,
bloc);
Array_type* at = Type::make_array_type(byte_type, len);
Expression_list* vals = new Expression_list();
vals->reserve(this->bits_.size());
for (std::vector<unsigned char>::const_iterator p = this->bits_.begin();
p != this->bits_.end();
++p)
vals->push_back(Expression::make_integer_ul(*p, byte_type, bloc));
return Expression::make_array_composite_literal(at, vals, bloc);
}
// The hash table mapping a ptrmask symbol name to the ptrmask variable.
Type::GC_gcbits_vars Type::gc_gcbits_vars;
// Return a ptrmask variable for a type. For a type descriptor this
// is only used for variables that are small enough to not need a
// gcprog, but for a global variable this is used for a variable of
// any size. PTRDATA is the number of bytes of the type that contain
// pointer data. PTRSIZE is the size of a pointer on the target
// system.
Bvariable*
Type::gc_ptrmask_var(Gogo* gogo, int64_t ptrsize, int64_t ptrdata)
{
Ptrmask ptrmask(ptrdata / ptrsize);
if (ptrdata >= ptrsize)
ptrmask.set_from(gogo, this, ptrsize, 0);
else
{
// This can happen in error cases. Just build an empty gcbits.
go_assert(saw_errors());
}
std::string sym_name = gogo->ptrmask_symbol_name(ptrmask.symname());
Bvariable* bvnull = NULL;
std::pair<GC_gcbits_vars::iterator, bool> ins =
Type::gc_gcbits_vars.insert(std::make_pair(sym_name, bvnull));
if (!ins.second)
{
// We've already built a GC symbol for this set of gcbits.
return ins.first->second;
}
Expression* val = ptrmask.constructor(gogo);
Translate_context context(gogo, NULL, NULL, NULL);
context.set_is_const();
Bexpression* bval = val->get_backend(&context);
std::string asm_name(go_selectively_encode_id(sym_name));
Btype *btype = val->type()->get_backend(gogo);
Bvariable* ret = gogo->backend()->implicit_variable(sym_name, asm_name,
btype, false, true,
true, 0);
gogo->backend()->implicit_variable_set_init(ret, sym_name, btype, false,
true, true, bval);
ins.first->second = ret;
return ret;
}
// A GCProg is used to build a program for the garbage collector.
// This is used for types with a lot of pointer data, to reduce the
// size of the data in the compiled program. The program is expanded
// at runtime. For the format, see runGCProg in libgo/go/runtime/mbitmap.go.
class GCProg
{
public:
GCProg()
: bytes_(), index_(0), nb_(0)
{}
// The number of bits described so far.
int64_t
bit_index() const
{ return this->index_; }
void
set_from(Gogo*, Type*, int64_t ptrsize, int64_t offset);
void
end();
Expression*
constructor(Gogo* gogo) const;
private:
void
ptr(int64_t);
bool
should_repeat(int64_t, int64_t);
void
repeat(int64_t, int64_t);
void
zero_until(int64_t);
void
lit(unsigned char);
void
varint(int64_t);
void
flushlit();
// Add a byte to the program.
void
byte(unsigned char x)
{ this->bytes_.push_back(x); }
// The maximum number of bytes of literal bits.
static const int max_literal = 127;
// The program.
std::vector<unsigned char> bytes_;
// The index of the last bit described.
int64_t index_;
// The current set of literal bits.
unsigned char b_[max_literal];
// The current number of literal bits.
int nb_;
};
// Set data in gcprog starting from OFFSET based on TYPE. OFFSET
// counts in bytes. PTRSIZE is the size of a pointer on the target
// system.
void
GCProg::set_from(Gogo* gogo, Type* type, int64_t ptrsize, int64_t offset)
{
switch (type->base()->classification())
{
default:
case Type::TYPE_NIL:
case Type::TYPE_CALL_MULTIPLE_RESULT:
case Type::TYPE_NAMED:
case Type::TYPE_FORWARD:
go_unreachable();
case Type::TYPE_ERROR:
case Type::TYPE_VOID:
case Type::TYPE_BOOLEAN:
case Type::TYPE_INTEGER:
case Type::TYPE_FLOAT:
case Type::TYPE_COMPLEX:
case Type::TYPE_SINK:
break;
case Type::TYPE_FUNCTION:
case Type::TYPE_POINTER:
case Type::TYPE_MAP:
case Type::TYPE_CHANNEL:
// These types are all a single pointer.
go_assert((offset % ptrsize) == 0);
this->ptr(offset / ptrsize);
break;
case Type::TYPE_STRING:
// A string starts with a single pointer.
go_assert((offset % ptrsize) == 0);
this->ptr(offset / ptrsize);
break;
case Type::TYPE_INTERFACE:
// An interface is two pointers.
go_assert((offset % ptrsize) == 0);
this->ptr(offset / ptrsize);
this->ptr((offset / ptrsize) + 1);
break;
case Type::TYPE_STRUCT:
{
if (!type->has_pointer())
return;
const Struct_field_list* fields = type->struct_type()->fields();
int64_t soffset = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
int64_t field_align;
if (!pf->type()->backend_type_field_align(gogo, &field_align))
{
go_assert(saw_errors());
return;
}
soffset = (soffset + (field_align - 1)) &~ (field_align - 1);
this->set_from(gogo, pf->type(), ptrsize, offset + soffset);
int64_t field_size;
if (!pf->type()->backend_type_size(gogo, &field_size))
{
go_assert(saw_errors());
return;
}
soffset += field_size;
}
}
break;
case Type::TYPE_ARRAY:
if (type->is_slice_type())
{
// A slice starts with a single pointer.
go_assert((offset % ptrsize) == 0);
this->ptr(offset / ptrsize);
break;
}
else
{
if (!type->has_pointer())
return;
int64_t len;
if (!type->array_type()->int_length(&len))
{
go_assert(saw_errors());
return;
}
Type* element_type = type->array_type()->element_type();
// Flatten array of array to a big array by multiplying counts.
while (element_type->array_type() != NULL
&& !element_type->is_slice_type())
{
int64_t ele_len;
if (!element_type->array_type()->int_length(&ele_len))
{
go_assert(saw_errors());
return;
}
len *= ele_len;
element_type = element_type->array_type()->element_type();
}
int64_t ele_size;
if (!element_type->backend_type_size(gogo, &ele_size))
{
go_assert(saw_errors());
return;
}
go_assert(len > 0 && ele_size > 0);
if (!this->should_repeat(ele_size / ptrsize, len))
{
// Cheaper to just emit the bits.
int64_t eoffset = 0;
for (int64_t i = 0; i < len; i++, eoffset += ele_size)
this->set_from(gogo, element_type, ptrsize, offset + eoffset);
}
else
{
go_assert((offset % ptrsize) == 0);
go_assert((ele_size % ptrsize) == 0);
this->set_from(gogo, element_type, ptrsize, offset);
this->zero_until((offset + ele_size) / ptrsize);
this->repeat(ele_size / ptrsize, len - 1);
}
break;
}
}
}
// Emit a 1 into the bit stream of a GC program at the given bit index.
void
GCProg::ptr(int64_t index)
{
go_assert(index >= this->index_);
this->zero_until(index);
this->lit(1);
}
// Return whether it is worthwhile to use a repeat to describe c
// elements of n bits each, compared to just emitting c copies of the
// n-bit description.
bool
GCProg::should_repeat(int64_t n, int64_t c)
{
// Repeat if there is more than 1 item and if the total data doesn't
// fit into four bytes.
return c > 1 && c * n > 4 * 8;
}
// Emit an instruction to repeat the description of the last n words c
// times (including the initial description, so c + 1 times in total).
void
GCProg::repeat(int64_t n, int64_t c)
{
if (n == 0 || c == 0)
return;
this->flushlit();
if (n < 128)
this->byte(0x80 | static_cast<unsigned char>(n & 0x7f));
else
{
this->byte(0x80);
this->varint(n);
}
this->varint(c);
this->index_ += n * c;
}
// Add zeros to the bit stream up to the given index.
void
GCProg::zero_until(int64_t index)
{
go_assert(index >= this->index_);
int64_t skip = index - this->index_;
if (skip == 0)
return;
if (skip < 4 * 8)
{
for (int64_t i = 0; i < skip; ++i)
this->lit(0);
return;
}
this->lit(0);
this->flushlit();
this->repeat(1, skip - 1);
}
// Add a single literal bit to the program.
void
GCProg::lit(unsigned char x)
{
if (this->nb_ == GCProg::max_literal)
this->flushlit();
this->b_[this->nb_] = x;
++this->nb_;
++this->index_;
}
// Emit the varint encoding of x.
void
GCProg::varint(int64_t x)
{
go_assert(x >= 0);
while (x >= 0x80)
{
this->byte(0x80 | static_cast<unsigned char>(x & 0x7f));
x >>= 7;
}
this->byte(static_cast<unsigned char>(x & 0x7f));
}
// Flush any pending literal bits.
void
GCProg::flushlit()
{
if (this->nb_ == 0)
return;
this->byte(static_cast<unsigned char>(this->nb_));
unsigned char bits = 0;
for (int i = 0; i < this->nb_; ++i)
{
bits |= this->b_[i] << (i % 8);
if ((i + 1) % 8 == 0)
{
this->byte(bits);
bits = 0;
}
}
if (this->nb_ % 8 != 0)
this->byte(bits);
this->nb_ = 0;
}
// Mark the end of a GC program.
void
GCProg::end()
{
this->flushlit();
this->byte(0);
}
// Return an Expression for the bytes in a GC program.
Expression*
GCProg::constructor(Gogo* gogo) const
{
Location bloc = Linemap::predeclared_location();
// The first four bytes are the length of the program in target byte
// order. Build a struct whose first type is uint32 to make this
// work.
Type* uint32_type = Type::lookup_integer_type("uint32");
Type* byte_type = gogo->lookup_global("byte")->type_value();
Expression* len = Expression::make_integer_ul(this->bytes_.size(), NULL,
bloc);
Array_type* at = Type::make_array_type(byte_type, len);
Struct_type* st = Type::make_builtin_struct_type(2, "len", uint32_type,
"bytes", at);
Expression_list* vals = new Expression_list();
vals->reserve(this->bytes_.size());
for (std::vector<unsigned char>::const_iterator p = this->bytes_.begin();
p != this->bytes_.end();
++p)
vals->push_back(Expression::make_integer_ul(*p, byte_type, bloc));
Expression* bytes = Expression::make_array_composite_literal(at, vals, bloc);
vals = new Expression_list();
vals->push_back(Expression::make_integer_ul(this->bytes_.size(), uint32_type,
bloc));
vals->push_back(bytes);
return Expression::make_struct_composite_literal(st, vals, bloc);
}
// Return a composite literal for the garbage collection program for
// this type. This is only used for types that are too large to use a
// ptrmask.
Expression*
Type::gcprog_constructor(Gogo* gogo, int64_t ptrsize, int64_t ptrdata)
{
Location bloc = Linemap::predeclared_location();
GCProg prog;
prog.set_from(gogo, this, ptrsize, 0);
int64_t offset = prog.bit_index() * ptrsize;
prog.end();
int64_t type_size;
if (!this->backend_type_size(gogo, &type_size))
{
go_assert(saw_errors());
return Expression::make_error(bloc);
}
go_assert(offset >= ptrdata && offset <= type_size);
return prog.constructor(gogo);
}
// Return a composite literal for the uncommon type information for
// this type. UNCOMMON_STRUCT_TYPE is the type of the uncommon type
// struct. If name is not NULL, it is the name of the type. If
// METHODS is not NULL, it is the list of methods. ONLY_VALUE_METHODS
// is true if only value methods should be included. At least one of
// NAME and METHODS must not be NULL.
Expression*
Type::uncommon_type_constructor(Gogo* gogo, Type* uncommon_type,
Named_type* name, const Methods* methods,
bool only_value_methods) const
{
Location bloc = Linemap::predeclared_location();
const Struct_field_list* fields = uncommon_type->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(3);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("name"));
++p;
go_assert(p->is_field_name("pkgPath"));
if (name == NULL)
{
vals->push_back(Expression::make_nil(bloc));
vals->push_back(Expression::make_nil(bloc));
}
else
{
Named_object* no = name->named_object();
std::string n = Gogo::unpack_hidden_name(no->name());
Expression* s = Expression::make_string(n, bloc);
vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
if (name->is_builtin())
vals->push_back(Expression::make_nil(bloc));
else
{
const Package* package = no->package();
const std::string& pkgpath(package == NULL
? gogo->pkgpath()
: package->pkgpath());
s = Expression::make_string(pkgpath, bloc);
vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
}
}
++p;
go_assert(p->is_field_name("methods"));
vals->push_back(this->methods_constructor(gogo, p->type(), methods,
only_value_methods));
++p;
go_assert(p == fields->end());
Expression* r = Expression::make_struct_composite_literal(uncommon_type,
vals, bloc);
return Expression::make_unary(OPERATOR_AND, r, bloc);
}
// Sort methods by name.
class Sort_methods
{
public:
bool
operator()(const std::pair<std::string, const Method*>& m1,
const std::pair<std::string, const Method*>& m2) const
{
return (Gogo::unpack_hidden_name(m1.first)
< Gogo::unpack_hidden_name(m2.first));
}
};
// Return a composite literal for the type method table for this type.
// METHODS_TYPE is the type of the table, and is a slice type.
// METHODS is the list of methods. If ONLY_VALUE_METHODS is true,
// then only value methods are used.
Expression*
Type::methods_constructor(Gogo* gogo, Type* methods_type,
const Methods* methods,
bool only_value_methods) const
{
Location bloc = Linemap::predeclared_location();
std::vector<std::pair<std::string, const Method*> > smethods;
if (methods != NULL)
{
smethods.reserve(methods->count());
for (Methods::const_iterator p = methods->begin();
p != methods->end();
++p)
{
if (p->second->is_ambiguous())
continue;
if (only_value_methods && !p->second->is_value_method())
continue;
// This is where we implement the magic //go:nointerface
// comment. If we saw that comment, we don't add this
// method to the type descriptor.
if (p->second->nointerface())
continue;
smethods.push_back(std::make_pair(p->first, p->second));
}
}
if (smethods.empty())
return Expression::make_slice_composite_literal(methods_type, NULL, bloc);
std::sort(smethods.begin(), smethods.end(), Sort_methods());
Type* method_type = methods_type->array_type()->element_type();
Expression_list* vals = new Expression_list();
vals->reserve(smethods.size());
for (std::vector<std::pair<std::string, const Method*> >::const_iterator p
= smethods.begin();
p != smethods.end();
++p)
vals->push_back(this->method_constructor(gogo, method_type, p->first,
p->second, only_value_methods));
return Expression::make_slice_composite_literal(methods_type, vals, bloc);
}
// Return a composite literal for a single method. METHOD_TYPE is the
// type of the entry. METHOD_NAME is the name of the method and M is
// the method information.
Expression*
Type::method_constructor(Gogo*, Type* method_type,
const std::string& method_name,
const Method* m,
bool only_value_methods) const
{
Location bloc = Linemap::predeclared_location();
const Struct_field_list* fields = method_type->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(5);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("name"));
const std::string n = Gogo::unpack_hidden_name(method_name);
Expression* s = Expression::make_string(n, bloc);
vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
++p;
go_assert(p->is_field_name("pkgPath"));
if (!Gogo::is_hidden_name(method_name))
vals->push_back(Expression::make_nil(bloc));
else
{
s = Expression::make_string(Gogo::hidden_name_pkgpath(method_name),
bloc);
vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
}
Named_object* no = (m->needs_stub_method()
? m->stub_object()
: m->named_object());
Function_type* mtype;
if (no->is_function())
mtype = no->func_value()->type();
else
mtype = no->func_declaration_value()->type();
go_assert(mtype->is_method());
Type* nonmethod_type = mtype->copy_without_receiver();
++p;
go_assert(p->is_field_name("mtyp"));
vals->push_back(Expression::make_type_descriptor(nonmethod_type, bloc));
++p;
go_assert(p->is_field_name("typ"));
bool want_pointer_receiver = !only_value_methods && m->is_value_method();
nonmethod_type = mtype->copy_with_receiver_as_param(want_pointer_receiver);
vals->push_back(Expression::make_type_descriptor(nonmethod_type, bloc));
++p;
go_assert(p->is_field_name("tfn"));
vals->push_back(Expression::make_func_code_reference(no, bloc));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(method_type, vals, bloc);
}
// Return a composite literal for the type descriptor of a plain type.
// RUNTIME_TYPE_KIND is the value of the kind field. If NAME is not
// NULL, it is the name to use as well as the list of methods.
Expression*
Type::plain_type_descriptor(Gogo* gogo, int runtime_type_kind,
Named_type* name)
{
return this->type_descriptor_constructor(gogo, runtime_type_kind,
name, NULL, true);
}
// Return the type reflection string for this type.
std::string
Type::reflection(Gogo* gogo) const
{
std::string ret;
// The do_reflection virtual function should set RET to the
// reflection string.
this->do_reflection(gogo, &ret);
return ret;
}
// Return whether the backend size of the type is known.
bool
Type::is_backend_type_size_known(Gogo* gogo)
{
switch (this->classification_)
{
case TYPE_ERROR:
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_FUNCTION:
case TYPE_POINTER:
case TYPE_NIL:
case TYPE_MAP:
case TYPE_CHANNEL:
case TYPE_INTERFACE:
return true;
case TYPE_STRUCT:
{
const Struct_field_list* fields = this->struct_type()->fields();
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
if (!pf->type()->is_backend_type_size_known(gogo))
return false;
return true;
}
case TYPE_ARRAY:
{
const Array_type* at = this->array_type();
if (at->length() == NULL)
return true;
else
{
Numeric_constant nc;
if (!at->length()->numeric_constant_value(&nc))
return false;
mpz_t ival;
if (!nc.to_int(&ival))
return false;
mpz_clear(ival);
return at->element_type()->is_backend_type_size_known(gogo);
}
}
case TYPE_NAMED:
this->named_type()->convert(gogo);
return this->named_type()->is_named_backend_type_size_known();
case TYPE_FORWARD:
{
Forward_declaration_type* fdt = this->forward_declaration_type();
return fdt->real_type()->is_backend_type_size_known(gogo);
}
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
go_unreachable();
default:
go_unreachable();
}
}
// If the size of the type can be determined, set *PSIZE to the size
// in bytes and return true. Otherwise, return false. This queries
// the backend.
bool
Type::backend_type_size(Gogo* gogo, int64_t *psize)
{
if (!this->is_backend_type_size_known(gogo))
return false;
if (this->is_error_type())
return false;
Btype* bt = this->get_backend_placeholder(gogo);
*psize = gogo->backend()->type_size(bt);
if (*psize == -1)
{
if (this->named_type() != NULL)
go_error_at(this->named_type()->location(),
"type %s larger than address space",
Gogo::message_name(this->named_type()->name()).c_str());
else
go_error_at(Linemap::unknown_location(),
"type %s larger than address space",
this->reflection(gogo).c_str());
// Make this an error type to avoid knock-on errors.
this->classification_ = TYPE_ERROR;
return false;
}
return true;
}
// If the alignment of the type can be determined, set *PALIGN to
// the alignment in bytes and return true. Otherwise, return false.
bool
Type::backend_type_align(Gogo* gogo, int64_t *palign)
{
if (!this->is_backend_type_size_known(gogo))
return false;
Btype* bt = this->get_backend_placeholder(gogo);
*palign = gogo->backend()->type_alignment(bt);
return true;
}
// Like backend_type_align, but return the alignment when used as a
// field.
bool
Type::backend_type_field_align(Gogo* gogo, int64_t *palign)
{
if (!this->is_backend_type_size_known(gogo))
return false;
Btype* bt = this->get_backend_placeholder(gogo);
*palign = gogo->backend()->type_field_alignment(bt);
return true;
}
// Get the ptrdata value for a type. This is the size of the prefix
// of the type that contains all pointers. Store the ptrdata in
// *PPTRDATA and return whether we found it.
bool
Type::backend_type_ptrdata(Gogo* gogo, int64_t* pptrdata)
{
*pptrdata = 0;
if (!this->has_pointer())
return true;
if (!this->is_backend_type_size_known(gogo))
return false;
switch (this->classification_)
{
case TYPE_ERROR:
return true;
case TYPE_FUNCTION:
case TYPE_POINTER:
case TYPE_MAP:
case TYPE_CHANNEL:
// These types are nothing but a pointer.
return this->backend_type_size(gogo, pptrdata);
case TYPE_INTERFACE:
// An interface is a struct of two pointers.
return this->backend_type_size(gogo, pptrdata);
case TYPE_STRING:
{
// A string is a struct whose first field is a pointer, and
// whose second field is not.
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* ptr = Type::make_pointer_type(uint8_type);
return ptr->backend_type_size(gogo, pptrdata);
}
case TYPE_NAMED:
case TYPE_FORWARD:
return this->base()->backend_type_ptrdata(gogo, pptrdata);
case TYPE_STRUCT:
{
const Struct_field_list* fields = this->struct_type()->fields();
int64_t offset = 0;
const Struct_field *ptr = NULL;
int64_t ptr_offset = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
int64_t field_align;
if (!pf->type()->backend_type_field_align(gogo, &field_align))
return false;
offset = (offset + (field_align - 1)) &~ (field_align - 1);
if (pf->type()->has_pointer())
{
ptr = &*pf;
ptr_offset = offset;
}
int64_t field_size;
if (!pf->type()->backend_type_size(gogo, &field_size))
return false;
offset += field_size;
}
if (ptr != NULL)
{
int64_t ptr_ptrdata;
if (!ptr->type()->backend_type_ptrdata(gogo, &ptr_ptrdata))
return false;
*pptrdata = ptr_offset + ptr_ptrdata;
}
return true;
}
case TYPE_ARRAY:
if (this->is_slice_type())
{
// A slice is a struct whose first field is a pointer, and
// whose remaining fields are not.
Type* element_type = this->array_type()->element_type();
Type* ptr = Type::make_pointer_type(element_type);
return ptr->backend_type_size(gogo, pptrdata);
}
else
{
Numeric_constant nc;
if (!this->array_type()->length()->numeric_constant_value(&nc))
return false;
int64_t len;
if (!nc.to_memory_size(&len))
return false;
Type* element_type = this->array_type()->element_type();
int64_t ele_size;
int64_t ele_ptrdata;
if (!element_type->backend_type_size(gogo, &ele_size)
|| !element_type->backend_type_ptrdata(gogo, &ele_ptrdata))
return false;
go_assert(ele_size > 0 && ele_ptrdata > 0);
*pptrdata = (len - 1) * ele_size + ele_ptrdata;
return true;
}
default:
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_SINK:
case TYPE_NIL:
case TYPE_CALL_MULTIPLE_RESULT:
go_unreachable();
}
}
// Get the ptrdata value to store in a type descriptor. This is
// normally the same as backend_type_ptrdata, but for a type that is
// large enough to use a gcprog we may need to store a different value
// if it ends with an array. If the gcprog uses a repeat descriptor
// for the array, and if the array element ends with non-pointer data,
// then the gcprog will produce a value that describes the complete
// array where the backend ptrdata will omit the non-pointer elements
// of the final array element. This is a subtle difference but the
// run time code checks it to verify that it has expanded a gcprog as
// expected.
bool
Type::descriptor_ptrdata(Gogo* gogo, int64_t* pptrdata)
{
int64_t backend_ptrdata;
if (!this->backend_type_ptrdata(gogo, &backend_ptrdata))
return false;
int64_t ptrsize;
if (!this->needs_gcprog(gogo, &ptrsize, &backend_ptrdata))
{
*pptrdata = backend_ptrdata;
return true;
}
GCProg prog;
prog.set_from(gogo, this, ptrsize, 0);
int64_t offset = prog.bit_index() * ptrsize;
go_assert(offset >= backend_ptrdata);
*pptrdata = offset;
return true;
}
// Default function to export a type.
void
Type::do_export(Export*) const
{
go_unreachable();
}
// Import a type.
Type*
Type::import_type(Import* imp)
{
if (imp->match_c_string("("))
return Function_type::do_import(imp);
else if (imp->match_c_string("*"))
return Pointer_type::do_import(imp);
else if (imp->match_c_string("struct "))
return Struct_type::do_import(imp);
else if (imp->match_c_string("["))
return Array_type::do_import(imp);
else if (imp->match_c_string("map "))
return Map_type::do_import(imp);
else if (imp->match_c_string("chan "))
return Channel_type::do_import(imp);
else if (imp->match_c_string("interface"))
return Interface_type::do_import(imp);
else
{
go_error_at(imp->location(), "import error: expected type");
return Type::make_error_type();
}
}
// Class Error_type.
// Return the backend representation of an Error type.
Btype*
Error_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->error_type();
}
// Return an expression for the type descriptor for an error type.
Expression*
Error_type::do_type_descriptor(Gogo*, Named_type*)
{
return Expression::make_error(Linemap::predeclared_location());
}
// We should not be asked for the reflection string for an error type.
void
Error_type::do_reflection(Gogo*, std::string*) const
{
go_assert(saw_errors());
}
Type*
Type::make_error_type()
{
static Error_type singleton_error_type;
return &singleton_error_type;
}
// Class Void_type.
// Get the backend representation of a void type.
Btype*
Void_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->void_type();
}
Type*
Type::make_void_type()
{
static Void_type singleton_void_type;
return &singleton_void_type;
}
// Class Boolean_type.
// Return the backend representation of the boolean type.
Btype*
Boolean_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->bool_type();
}
// Make the type descriptor.
Expression*
Boolean_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
if (name != NULL)
return this->plain_type_descriptor(gogo, RUNTIME_TYPE_KIND_BOOL, name);
else
{
Named_object* no = gogo->lookup_global("bool");
go_assert(no != NULL);
return Type::type_descriptor(gogo, no->type_value());
}
}
Type*
Type::make_boolean_type()
{
static Boolean_type boolean_type;
return &boolean_type;
}
// The named type "bool".
static Named_type* named_bool_type;
// Get the named type "bool".
Named_type*
Type::lookup_bool_type()
{
return named_bool_type;
}
// Make the named type "bool".
Named_type*
Type::make_named_bool_type()
{
Type* bool_type = Type::make_boolean_type();
Named_object* named_object =
Named_object::make_type("bool", NULL, bool_type,
Linemap::predeclared_location());
Named_type* named_type = named_object->type_value();
named_bool_type = named_type;
return named_type;
}
// Class Integer_type.
Integer_type::Named_integer_types Integer_type::named_integer_types;
// Create a new integer type. Non-abstract integer types always have
// names.
Named_type*
Integer_type::create_integer_type(const char* name, bool is_unsigned,
int bits, int runtime_type_kind)
{
Integer_type* integer_type = new Integer_type(false, is_unsigned, bits,
runtime_type_kind);
std::string sname(name);
Named_object* named_object =
Named_object::make_type(sname, NULL, integer_type,
Linemap::predeclared_location());
Named_type* named_type = named_object->type_value();
std::pair<Named_integer_types::iterator, bool> ins =
Integer_type::named_integer_types.insert(std::make_pair(sname, named_type));
go_assert(ins.second);
return named_type;
}
// Look up an existing integer type.
Named_type*
Integer_type::lookup_integer_type(const char* name)
{
Named_integer_types::const_iterator p =
Integer_type::named_integer_types.find(name);
go_assert(p != Integer_type::named_integer_types.end());
return p->second;
}
// Create a new abstract integer type.
Integer_type*
Integer_type::create_abstract_integer_type()
{
static Integer_type* abstract_type;
if (abstract_type == NULL)
{
Type* int_type = Type::lookup_integer_type("int");
abstract_type = new Integer_type(true, false,
int_type->integer_type()->bits(),
RUNTIME_TYPE_KIND_INT);
}
return abstract_type;
}
// Create a new abstract character type.
Integer_type*
Integer_type::create_abstract_character_type()
{
static Integer_type* abstract_type;
if (abstract_type == NULL)
{
abstract_type = new Integer_type(true, false, 32,
RUNTIME_TYPE_KIND_INT32);
abstract_type->set_is_rune();
}
return abstract_type;
}
// Integer type compatibility.
bool
Integer_type::is_identical(const Integer_type* t) const
{
if (this->is_unsigned_ != t->is_unsigned_ || this->bits_ != t->bits_)
return false;
return this->is_abstract_ == t->is_abstract_;
}
// Hash code.
unsigned int
Integer_type::do_hash_for_method(Gogo*) const
{
return ((this->bits_ << 4)
+ ((this->is_unsigned_ ? 1 : 0) << 8)
+ ((this->is_abstract_ ? 1 : 0) << 9));
}
// Convert an Integer_type to the backend representation.
Btype*
Integer_type::do_get_backend(Gogo* gogo)
{
if (this->is_abstract_)
{
go_assert(saw_errors());
return gogo->backend()->error_type();
}
return gogo->backend()->integer_type(this->is_unsigned_, this->bits_);
}
// The type descriptor for an integer type. Integer types are always
// named.
Expression*
Integer_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
go_assert(name != NULL || saw_errors());
return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name);
}
// We should not be asked for the reflection string of a basic type.
void
Integer_type::do_reflection(Gogo*, std::string*) const
{
go_assert(saw_errors());
}
// Make an integer type.
Named_type*
Type::make_integer_type(const char* name, bool is_unsigned, int bits,
int runtime_type_kind)
{
return Integer_type::create_integer_type(name, is_unsigned, bits,
runtime_type_kind);
}
// Make an abstract integer type.
Integer_type*
Type::make_abstract_integer_type()
{
return Integer_type::create_abstract_integer_type();
}
// Make an abstract character type.
Integer_type*
Type::make_abstract_character_type()
{
return Integer_type::create_abstract_character_type();
}
// Look up an integer type.
Named_type*
Type::lookup_integer_type(const char* name)
{
return Integer_type::lookup_integer_type(name);
}
// Class Float_type.
Float_type::Named_float_types Float_type::named_float_types;
// Create a new float type. Non-abstract float types always have
// names.
Named_type*
Float_type::create_float_type(const char* name, int bits,
int runtime_type_kind)
{
Float_type* float_type = new Float_type(false, bits, runtime_type_kind);
std::string sname(name);
Named_object* named_object =
Named_object::make_type(sname, NULL, float_type,
Linemap::predeclared_location());
Named_type* named_type = named_object->type_value();
std::pair<Named_float_types::iterator, bool> ins =
Float_type::named_float_types.insert(std::make_pair(sname, named_type));
go_assert(ins.second);
return named_type;
}
// Look up an existing float type.
Named_type*
Float_type::lookup_float_type(const char* name)
{
Named_float_types::const_iterator p =
Float_type::named_float_types.find(name);
go_assert(p != Float_type::named_float_types.end());
return p->second;
}
// Create a new abstract float type.
Float_type*
Float_type::create_abstract_float_type()
{
static Float_type* abstract_type;
if (abstract_type == NULL)
abstract_type = new Float_type(true, 64, RUNTIME_TYPE_KIND_FLOAT64);
return abstract_type;
}
// Whether this type is identical with T.
bool
Float_type::is_identical(const Float_type* t) const
{
if (this->bits_ != t->bits_)
return false;
return this->is_abstract_ == t->is_abstract_;
}
// Hash code.
unsigned int
Float_type::do_hash_for_method(Gogo*) const
{
return (this->bits_ << 4) + ((this->is_abstract_ ? 1 : 0) << 8);
}
// Convert to the backend representation.
Btype*
Float_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->float_type(this->bits_);
}
// The type descriptor for a float type. Float types are always named.
Expression*
Float_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
go_assert(name != NULL || saw_errors());
return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name);
}
// We should not be asked for the reflection string of a basic type.
void
Float_type::do_reflection(Gogo*, std::string*) const
{
go_assert(saw_errors());
}
// Make a floating point type.
Named_type*
Type::make_float_type(const char* name, int bits, int runtime_type_kind)
{
return Float_type::create_float_type(name, bits, runtime_type_kind);
}
// Make an abstract float type.
Float_type*
Type::make_abstract_float_type()
{
return Float_type::create_abstract_float_type();
}
// Look up a float type.
Named_type*
Type::lookup_float_type(const char* name)
{
return Float_type::lookup_float_type(name);
}
// Class Complex_type.
Complex_type::Named_complex_types Complex_type::named_complex_types;
// Create a new complex type. Non-abstract complex types always have
// names.
Named_type*
Complex_type::create_complex_type(const char* name, int bits,
int runtime_type_kind)
{
Complex_type* complex_type = new Complex_type(false, bits,
runtime_type_kind);
std::string sname(name);
Named_object* named_object =
Named_object::make_type(sname, NULL, complex_type,
Linemap::predeclared_location());
Named_type* named_type = named_object->type_value();
std::pair<Named_complex_types::iterator, bool> ins =
Complex_type::named_complex_types.insert(std::make_pair(sname,
named_type));
go_assert(ins.second);
return named_type;
}
// Look up an existing complex type.
Named_type*
Complex_type::lookup_complex_type(const char* name)
{
Named_complex_types::const_iterator p =
Complex_type::named_complex_types.find(name);
go_assert(p != Complex_type::named_complex_types.end());
return p->second;
}
// Create a new abstract complex type.
Complex_type*
Complex_type::create_abstract_complex_type()
{
static Complex_type* abstract_type;
if (abstract_type == NULL)
abstract_type = new Complex_type(true, 128, RUNTIME_TYPE_KIND_COMPLEX128);
return abstract_type;
}
// Whether this type is identical with T.
bool
Complex_type::is_identical(const Complex_type *t) const
{
if (this->bits_ != t->bits_)
return false;
return this->is_abstract_ == t->is_abstract_;
}
// Hash code.
unsigned int
Complex_type::do_hash_for_method(Gogo*) const
{
return (this->bits_ << 4) + ((this->is_abstract_ ? 1 : 0) << 8);
}
// Convert to the backend representation.
Btype*
Complex_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->complex_type(this->bits_);
}
// The type descriptor for a complex type. Complex types are always
// named.
Expression*
Complex_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
go_assert(name != NULL || saw_errors());
return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name);
}
// We should not be asked for the reflection string of a basic type.
void
Complex_type::do_reflection(Gogo*, std::string*) const
{
go_assert(saw_errors());
}
// Make a complex type.
Named_type*
Type::make_complex_type(const char* name, int bits, int runtime_type_kind)
{
return Complex_type::create_complex_type(name, bits, runtime_type_kind);
}
// Make an abstract complex type.
Complex_type*
Type::make_abstract_complex_type()
{
return Complex_type::create_abstract_complex_type();
}
// Look up a complex type.
Named_type*
Type::lookup_complex_type(const char* name)
{
return Complex_type::lookup_complex_type(name);
}
// Class String_type.
// Convert String_type to the backend representation. A string is a
// struct with two fields: a pointer to the characters and a length.
Btype*
String_type::do_get_backend(Gogo* gogo)
{
static Btype* backend_string_type;
if (backend_string_type == NULL)
{
std::vector<Backend::Btyped_identifier> fields(2);
Type* b = gogo->lookup_global("byte")->type_value();
Type* pb = Type::make_pointer_type(b);
// We aren't going to get back to this field to finish the
// backend representation, so force it to be finished now.
if (!gogo->named_types_are_converted())
{
Btype* bt = pb->get_backend_placeholder(gogo);
pb->finish_backend(gogo, bt);
}
fields[0].name = "__data";
fields[0].btype = pb->get_backend(gogo);
fields[0].location = Linemap::predeclared_location();
Type* int_type = Type::lookup_integer_type("int");
fields[1].name = "__length";
fields[1].btype = int_type->get_backend(gogo);
fields[1].location = fields[0].location;
backend_string_type = gogo->backend()->struct_type(fields);
}
return backend_string_type;
}
// The type descriptor for the string type.
Expression*
String_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
if (name != NULL)
return this->plain_type_descriptor(gogo, RUNTIME_TYPE_KIND_STRING, name);
else
{
Named_object* no = gogo->lookup_global("string");
go_assert(no != NULL);
return Type::type_descriptor(gogo, no->type_value());
}
}
// We should not be asked for the reflection string of a basic type.
void
String_type::do_reflection(Gogo*, std::string* ret) const
{
ret->append("string");
}
// Make a string type.
Type*
Type::make_string_type()
{
static String_type string_type;
return &string_type;
}
// The named type "string".
static Named_type* named_string_type;
// Get the named type "string".
Named_type*
Type::lookup_string_type()
{
return named_string_type;
}
// Make the named type string.
Named_type*
Type::make_named_string_type()
{
Type* string_type = Type::make_string_type();
Named_object* named_object =
Named_object::make_type("string", NULL, string_type,
Linemap::predeclared_location());
Named_type* named_type = named_object->type_value();
named_string_type = named_type;
return named_type;
}
// The sink type. This is the type of the blank identifier _. Any
// type may be assigned to it.
class Sink_type : public Type
{
public:
Sink_type()
: Type(TYPE_SINK)
{ }
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
Btype*
do_get_backend(Gogo*)
{ go_unreachable(); }
Expression*
do_type_descriptor(Gogo*, Named_type*)
{ go_unreachable(); }
void
do_reflection(Gogo*, std::string*) const
{ go_unreachable(); }
void
do_mangled_name(Gogo*, std::string*) const
{ go_unreachable(); }
};
// Make the sink type.
Type*
Type::make_sink_type()
{
static Sink_type sink_type;
return &sink_type;
}
// Class Function_type.
// Traversal.
int
Function_type::do_traverse(Traverse* traverse)
{
if (this->receiver_ != NULL
&& Type::traverse(this->receiver_->type(), traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
if (this->parameters_ != NULL
&& this->parameters_->traverse(traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
if (this->results_ != NULL
&& this->results_->traverse(traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
return TRAVERSE_CONTINUE;
}
// Returns whether T is a valid redeclaration of this type. If this
// returns false, and REASON is not NULL, *REASON may be set to a
// brief explanation of why it returned false.
bool
Function_type::is_valid_redeclaration(const Function_type* t,
std::string* reason) const
{
if (!this->is_identical(t, false, COMPARE_TAGS, true, reason))
return false;
// A redeclaration of a function is required to use the same names
// for the receiver and parameters.
if (this->receiver() != NULL
&& this->receiver()->name() != t->receiver()->name())
{
if (reason != NULL)
*reason = "receiver name changed";
return false;
}
const Typed_identifier_list* parms1 = this->parameters();
const Typed_identifier_list* parms2 = t->parameters();
if (parms1 != NULL)
{
Typed_identifier_list::const_iterator p1 = parms1->begin();
for (Typed_identifier_list::const_iterator p2 = parms2->begin();
p2 != parms2->end();
++p2, ++p1)
{
if (p1->name() != p2->name())
{
if (reason != NULL)
*reason = "parameter name changed";
return false;
}
// This is called at parse time, so we may have unknown
// types.
Type* t1 = p1->type()->forwarded();
Type* t2 = p2->type()->forwarded();
if (t1 != t2
&& t1->forward_declaration_type() != NULL
&& (t2->forward_declaration_type() == NULL
|| (t1->forward_declaration_type()->named_object()
!= t2->forward_declaration_type()->named_object())))
return false;
}
}
const Typed_identifier_list* results1 = this->results();
const Typed_identifier_list* results2 = t->results();
if (results1 != NULL)
{
Typed_identifier_list::const_iterator res1 = results1->begin();
for (Typed_identifier_list::const_iterator res2 = results2->begin();
res2 != results2->end();
++res2, ++res1)
{
if (res1->name() != res2->name())
{
if (reason != NULL)
*reason = "result name changed";
return false;
}
// This is called at parse time, so we may have unknown
// types.
Type* t1 = res1->type()->forwarded();
Type* t2 = res2->type()->forwarded();
if (t1 != t2
&& t1->forward_declaration_type() != NULL
&& (t2->forward_declaration_type() == NULL
|| (t1->forward_declaration_type()->named_object()
!= t2->forward_declaration_type()->named_object())))
return false;
}
}
return true;
}
// Check whether T is the same as this type.
bool
Function_type::is_identical(const Function_type* t, bool ignore_receiver,
Cmp_tags cmp_tags, bool errors_are_identical,
std::string* reason) const
{
if (this->is_backend_function_type() != t->is_backend_function_type())
return false;
if (!ignore_receiver)
{
const Typed_identifier* r1 = this->receiver();
const Typed_identifier* r2 = t->receiver();
if ((r1 != NULL) != (r2 != NULL))
{
if (reason != NULL)
*reason = _("different receiver types");
return false;
}
if (r1 != NULL)
{
if (!Type::are_identical_cmp_tags(r1->type(), r2->type(), cmp_tags,
errors_are_identical, reason))
{
if (reason != NULL && !reason->empty())
*reason = "receiver: " + *reason;
return false;
}
}
}
const Typed_identifier_list* parms1 = this->parameters();
if (parms1 != NULL && parms1->empty())
parms1 = NULL;
const Typed_identifier_list* parms2 = t->parameters();
if (parms2 != NULL && parms2->empty())
parms2 = NULL;
if ((parms1 != NULL) != (parms2 != NULL))
{
if (reason != NULL)
*reason = _("different number of parameters");
return false;
}
if (parms1 != NULL)
{
Typed_identifier_list::const_iterator p1 = parms1->begin();
for (Typed_identifier_list::const_iterator p2 = parms2->begin();
p2 != parms2->end();
++p2, ++p1)
{
if (p1 == parms1->end())
{
if (reason != NULL)
*reason = _("different number of parameters");
return false;
}
if (!Type::are_identical_cmp_tags(p1->type(), p2->type(), cmp_tags,
errors_are_identical, NULL))
{
if (reason != NULL)
*reason = _("different parameter types");
return false;
}
}
if (p1 != parms1->end())
{
if (reason != NULL)
*reason = _("different number of parameters");
return false;
}
}
if (this->is_varargs() != t->is_varargs())
{
if (reason != NULL)
*reason = _("different varargs");
return false;
}
const Typed_identifier_list* results1 = this->results();
if (results1 != NULL && results1->empty())
results1 = NULL;
const Typed_identifier_list* results2 = t->results();
if (results2 != NULL && results2->empty())
results2 = NULL;
if ((results1 != NULL) != (results2 != NULL))
{
if (reason != NULL)
*reason = _("different number of results");
return false;
}
if (results1 != NULL)
{
Typed_identifier_list::const_iterator res1 = results1->begin();
for (Typed_identifier_list::const_iterator res2 = results2->begin();
res2 != results2->end();
++res2, ++res1)
{
if (res1 == results1->end())
{
if (reason != NULL)
*reason = _("different number of results");
return false;
}
if (!Type::are_identical_cmp_tags(res1->type(), res2->type(),
cmp_tags, errors_are_identical,
NULL))
{
if (reason != NULL)
*reason = _("different result types");
return false;
}
}
if (res1 != results1->end())
{
if (reason != NULL)
*reason = _("different number of results");
return false;
}
}
return true;
}
// Hash code.
unsigned int
Function_type::do_hash_for_method(Gogo* gogo) const
{
unsigned int ret = 0;
// We ignore the receiver type for hash codes, because we need to
// get the same hash code for a method in an interface and a method
// declared for a type. The former will not have a receiver.
if (this->parameters_ != NULL)
{
int shift = 1;
for (Typed_identifier_list::const_iterator p = this->parameters_->begin();
p != this->parameters_->end();
++p, ++shift)
ret += p->type()->hash_for_method(gogo) << shift;
}
if (this->results_ != NULL)
{
int shift = 2;
for (Typed_identifier_list::const_iterator p = this->results_->begin();
p != this->results_->end();
++p, ++shift)
ret += p->type()->hash_for_method(gogo) << shift;
}
if (this->is_varargs_)
ret += 1;
ret <<= 4;
return ret;
}
// Hash result parameters.
unsigned int
Function_type::Results_hash::operator()(const Typed_identifier_list* t) const
{
unsigned int hash = 0;
for (Typed_identifier_list::const_iterator p = t->begin();
p != t->end();
++p)
{
hash <<= 2;
hash = Type::hash_string(p->name(), hash);
hash += p->type()->hash_for_method(NULL);
}
return hash;
}
// Compare result parameters so that can map identical result
// parameters to a single struct type.
bool
Function_type::Results_equal::operator()(const Typed_identifier_list* a,
const Typed_identifier_list* b) const
{
if (a->size() != b->size())
return false;
Typed_identifier_list::const_iterator pa = a->begin();
for (Typed_identifier_list::const_iterator pb = b->begin();
pb != b->end();
++pa, ++pb)
{
if (pa->name() != pb->name()
|| !Type::are_identical(pa->type(), pb->type(), true, NULL))
return false;
}
return true;
}
// Hash from results to a backend struct type.
Function_type::Results_structs Function_type::results_structs;
// Get the backend representation for a function type.
Btype*
Function_type::get_backend_fntype(Gogo* gogo)
{
if (this->fnbtype_ == NULL)
{
Backend::Btyped_identifier breceiver;
if (this->receiver_ != NULL)
{
breceiver.name = Gogo::unpack_hidden_name(this->receiver_->name());
// We always pass the address of the receiver parameter, in
// order to make interface calls work with unknown types.
Type* rtype = this->receiver_->type();
if (rtype->points_to() == NULL)
rtype = Type::make_pointer_type(rtype);
breceiver.btype = rtype->get_backend(gogo);
breceiver.location = this->receiver_->location();
}
std::vector<Backend::Btyped_identifier> bparameters;
if (this->parameters_ != NULL)
{
bparameters.resize(this->parameters_->size());
size_t i = 0;
for (Typed_identifier_list::const_iterator p =
this->parameters_->begin(); p != this->parameters_->end();
++p, ++i)
{
bparameters[i].name = Gogo::unpack_hidden_name(p->name());
bparameters[i].btype = p->type()->get_backend(gogo);
bparameters[i].location = p->location();
}
go_assert(i == bparameters.size());
}
std::vector<Backend::Btyped_identifier> bresults;
Btype* bresult_struct = NULL;
if (this->results_ != NULL)
{
bresults.resize(this->results_->size());
size_t i = 0;
for (Typed_identifier_list::const_iterator p =
this->results_->begin();
p != this->results_->end();
++p, ++i)
{
bresults[i].name = Gogo::unpack_hidden_name(p->name());
bresults[i].btype = p->type()->get_backend(gogo);
bresults[i].location = p->location();
}
go_assert(i == bresults.size());
if (this->results_->size() > 1)
{
// Use the same results struct for all functions that
// return the same set of results. This is useful to
// unify calls to interface methods with other calls.
std::pair<Typed_identifier_list*, Btype*> val;
val.first = this->results_;
val.second = NULL;
std::pair<Results_structs::iterator, bool> ins =
Function_type::results_structs.insert(val);
if (ins.second)
{
// Build a new struct type.
Struct_field_list* sfl = new Struct_field_list;
for (Typed_identifier_list::const_iterator p =
this->results_->begin();
p != this->results_->end();
++p)
{
Typed_identifier tid = *p;
if (tid.name().empty())
tid = Typed_identifier("UNNAMED", tid.type(),
tid.location());
sfl->push_back(Struct_field(tid));
}
Struct_type* st = Type::make_struct_type(sfl,
this->location());
st->set_is_struct_incomparable();
ins.first->second = st->get_backend(gogo);
}
bresult_struct = ins.first->second;
}
}
this->fnbtype_ = gogo->backend()->function_type(breceiver, bparameters,
bresults, bresult_struct,
this->location());
}
return this->fnbtype_;
}
// Get the backend representation for a Go function type.
Btype*
Function_type::do_get_backend(Gogo* gogo)
{
// When we do anything with a function value other than call it, it
// is represented as a pointer to a struct whose first field is the
// actual function. So that is what we return as the type of a Go
// function.
Location loc = this->location();
Btype* struct_type =
gogo->backend()->placeholder_struct_type("__go_descriptor", loc);
Btype* ptr_struct_type = gogo->backend()->pointer_type(struct_type);
std::vector<Backend::Btyped_identifier> fields(1);
fields[0].name = "code";
fields[0].btype = this->get_backend_fntype(gogo);
fields[0].location = loc;
if (!gogo->backend()->set_placeholder_struct_type(struct_type, fields))
return gogo->backend()->error_type();
return ptr_struct_type;
}
// The type of a function type descriptor.
Type*
Function_type::make_function_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* bool_type = Type::lookup_bool_type();
Type* slice_type = Type::make_array_type(ptdt, NULL);
Struct_type* s = Type::make_builtin_struct_type(4,
"", tdt,
"dotdotdot", bool_type,
"in", slice_type,
"out", slice_type);
ret = Type::make_builtin_named_type("FuncType", s);
}
return ret;
}
// The type descriptor for a function type.
Expression*
Function_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* ftdt = Function_type::make_function_type_descriptor_type();
const Struct_field_list* fields = ftdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(4);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_FUNC,
name, NULL, true));
++p;
go_assert(p->is_field_name("dotdotdot"));
vals->push_back(Expression::make_boolean(this->is_varargs(), bloc));
++p;
go_assert(p->is_field_name("in"));
vals->push_back(this->type_descriptor_params(p->type(), this->receiver(),
this->parameters()));
++p;
go_assert(p->is_field_name("out"));
vals->push_back(this->type_descriptor_params(p->type(), NULL,
this->results()));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(ftdt, vals, bloc);
}
// Return a composite literal for the parameters or results of a type
// descriptor.
Expression*
Function_type::type_descriptor_params(Type* params_type,
const Typed_identifier* receiver,
const Typed_identifier_list* params)
{
Location bloc = Linemap::predeclared_location();
if (receiver == NULL && params == NULL)
return Expression::make_slice_composite_literal(params_type, NULL, bloc);
Expression_list* vals = new Expression_list();
vals->reserve((params == NULL ? 0 : params->size())
+ (receiver != NULL ? 1 : 0));
if (receiver != NULL)
vals->push_back(Expression::make_type_descriptor(receiver->type(), bloc));
if (params != NULL)
{
for (Typed_identifier_list::const_iterator p = params->begin();
p != params->end();
++p)
vals->push_back(Expression::make_type_descriptor(p->type(), bloc));
}
return Expression::make_slice_composite_literal(params_type, vals, bloc);
}
// The reflection string.
void
Function_type::do_reflection(Gogo* gogo, std::string* ret) const
{
// FIXME: Turn this off until we straighten out the type of the
// struct field used in a go statement which calls a method.
// go_assert(this->receiver_ == NULL);
ret->append("func");
if (this->receiver_ != NULL)
{
ret->push_back('(');
this->append_reflection(this->receiver_->type(), gogo, ret);
ret->push_back(')');
}
ret->push_back('(');
const Typed_identifier_list* params = this->parameters();
if (params != NULL)
{
bool is_varargs = this->is_varargs_;
for (Typed_identifier_list::const_iterator p = params->begin();
p != params->end();
++p)
{
if (p != params->begin())
ret->append(", ");
if (!is_varargs || p + 1 != params->end())
this->append_reflection(p->type(), gogo, ret);
else
{
ret->append("...");
this->append_reflection(p->type()->array_type()->element_type(),
gogo, ret);
}
}
}
ret->push_back(')');
const Typed_identifier_list* results = this->results();
if (results != NULL && !results->empty())
{
if (results->size() == 1)
ret->push_back(' ');
else
ret->append(" (");
for (Typed_identifier_list::const_iterator p = results->begin();
p != results->end();
++p)
{
if (p != results->begin())
ret->append(", ");
this->append_reflection(p->type(), gogo, ret);
}
if (results->size() > 1)
ret->push_back(')');
}
}
// Export a function type.
void
Function_type::do_export(Export* exp) const
{
// We don't write out the receiver. The only function types which
// should have a receiver are the ones associated with explicitly
// defined methods. For those the receiver type is written out by
// Function::export_func.
exp->write_c_string("(");
bool first = true;
if (this->parameters_ != NULL)
{
bool is_varargs = this->is_varargs_;
for (Typed_identifier_list::const_iterator p =
this->parameters_->begin();
p != this->parameters_->end();
++p)
{
if (first)
first = false;
else
exp->write_c_string(", ");
exp->write_name(p->name());
exp->write_c_string(" ");
if (!is_varargs || p + 1 != this->parameters_->end())
exp->write_type(p->type());
else
{
exp->write_c_string("...");
exp->write_type(p->type()->array_type()->element_type());
}
}
}
exp->write_c_string(")");
const Typed_identifier_list* results = this->results_;
if (results != NULL)
{
exp->write_c_string(" ");
if (results->size() == 1 && results->begin()->name().empty())
exp->write_type(results->begin()->type());
else
{
first = true;
exp->write_c_string("(");
for (Typed_identifier_list::const_iterator p = results->begin();
p != results->end();
++p)
{
if (first)
first = false;
else
exp->write_c_string(", ");
exp->write_name(p->name());
exp->write_c_string(" ");
exp->write_type(p->type());
}
exp->write_c_string(")");
}
}
}
// Import a function type.
Function_type*
Function_type::do_import(Import* imp)
{
imp->require_c_string("(");
Typed_identifier_list* parameters;
bool is_varargs = false;
if (imp->peek_char() == ')')
parameters = NULL;
else
{
parameters = new Typed_identifier_list();
while (true)
{
std::string name = imp->read_name();
imp->require_c_string(" ");
if (imp->match_c_string("..."))
{
imp->advance(3);
is_varargs = true;
}
Type* ptype = imp->read_type();
if (is_varargs)
ptype = Type::make_array_type(ptype, NULL);
parameters->push_back(Typed_identifier(name, ptype,
imp->location()));
if (imp->peek_char() != ',')
break;
go_assert(!is_varargs);
imp->require_c_string(", ");
}
}
imp->require_c_string(")");
Typed_identifier_list* results;
if (imp->peek_char() != ' ')
results = NULL;
else
{
imp->advance(1);
results = new Typed_identifier_list;
if (imp->peek_char() != '(')
{
Type* rtype = imp->read_type();
results->push_back(Typed_identifier("", rtype, imp->location()));
}
else
{
imp->advance(1);
while (true)
{
std::string name = imp->read_name();
imp->require_c_string(" ");
Type* rtype = imp->read_type();
results->push_back(Typed_identifier(name, rtype,
imp->location()));
if (imp->peek_char() != ',')
break;
imp->require_c_string(", ");
}
imp->require_c_string(")");
}
}
Function_type* ret = Type::make_function_type(NULL, parameters, results,
imp->location());
if (is_varargs)
ret->set_is_varargs();
return ret;
}
// Make a copy of a function type without a receiver.
Function_type*
Function_type::copy_without_receiver() const
{
go_assert(this->is_method());
Function_type *ret = Type::make_function_type(NULL, this->parameters_,
this->results_,
this->location_);
if (this->is_varargs())
ret->set_is_varargs();
if (this->is_builtin())
ret->set_is_builtin();
return ret;
}
// Make a copy of a function type with a receiver.
Function_type*
Function_type::copy_with_receiver(Type* receiver_type) const
{
go_assert(!this->is_method());
Typed_identifier* receiver = new Typed_identifier("", receiver_type,
this->location_);
Function_type* ret = Type::make_function_type(receiver, this->parameters_,
this->results_,
this->location_);
if (this->is_varargs_)
ret->set_is_varargs();
return ret;
}
// Make a copy of a function type with the receiver as the first
// parameter.
Function_type*
Function_type::copy_with_receiver_as_param(bool want_pointer_receiver) const
{
go_assert(this->is_method());
Typed_identifier_list* new_params = new Typed_identifier_list();
Type* rtype = this->receiver_->type();
if (want_pointer_receiver)
rtype = Type::make_pointer_type(rtype);
Typed_identifier receiver(this->receiver_->name(), rtype,
this->receiver_->location());
new_params->push_back(receiver);
const Typed_identifier_list* orig_params = this->parameters_;
if (orig_params != NULL && !orig_params->empty())
{
for (Typed_identifier_list::const_iterator p = orig_params->begin();
p != orig_params->end();
++p)
new_params->push_back(*p);
}
return Type::make_function_type(NULL, new_params, this->results_,
this->location_);
}
// Make a copy of a function type ignoring any receiver and adding a
// closure parameter.
Function_type*
Function_type::copy_with_names() const
{
Typed_identifier_list* new_params = new Typed_identifier_list();
const Typed_identifier_list* orig_params = this->parameters_;
if (orig_params != NULL && !orig_params->empty())
{
static int count;
char buf[50];
for (Typed_identifier_list::const_iterator p = orig_params->begin();
p != orig_params->end();
++p)
{
snprintf(buf, sizeof buf, "pt.%u", count);
++count;
new_params->push_back(Typed_identifier(buf, p->type(),
p->location()));
}
}
const Typed_identifier_list* orig_results = this->results_;
Typed_identifier_list* new_results;
if (orig_results == NULL || orig_results->empty())
new_results = NULL;
else
{
new_results = new Typed_identifier_list();
for (Typed_identifier_list::const_iterator p = orig_results->begin();
p != orig_results->end();
++p)
new_results->push_back(Typed_identifier("", p->type(),
p->location()));
}
return Type::make_function_type(NULL, new_params, new_results,
this->location());
}
// Make a function type.
Function_type*
Type::make_function_type(Typed_identifier* receiver,
Typed_identifier_list* parameters,
Typed_identifier_list* results,
Location location)
{
return new Function_type(receiver, parameters, results, location);
}
// Make a backend function type.
Backend_function_type*
Type::make_backend_function_type(Typed_identifier* receiver,
Typed_identifier_list* parameters,
Typed_identifier_list* results,
Location location)
{
return new Backend_function_type(receiver, parameters, results, location);
}
// Class Pointer_type.
// Traversal.
int
Pointer_type::do_traverse(Traverse* traverse)
{
return Type::traverse(this->to_type_, traverse);
}
// Hash code.
unsigned int
Pointer_type::do_hash_for_method(Gogo* gogo) const
{
return this->to_type_->hash_for_method(gogo) << 4;
}
// Get the backend representation for a pointer type.
Btype*
Pointer_type::do_get_backend(Gogo* gogo)
{
Btype* to_btype = this->to_type_->get_backend(gogo);
return gogo->backend()->pointer_type(to_btype);
}
// The type of a pointer type descriptor.
Type*
Pointer_type::make_pointer_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Struct_type* s = Type::make_builtin_struct_type(2,
"", tdt,
"elem", ptdt);
ret = Type::make_builtin_named_type("PtrType", s);
}
return ret;
}
// The type descriptor for a pointer type.
Expression*
Pointer_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
if (this->is_unsafe_pointer_type())
{
go_assert(name != NULL);
return this->plain_type_descriptor(gogo,
RUNTIME_TYPE_KIND_UNSAFE_POINTER,
name);
}
else
{
Location bloc = Linemap::predeclared_location();
const Methods* methods;
Type* deref = this->points_to();
if (deref->named_type() != NULL)
methods = deref->named_type()->methods();
else if (deref->struct_type() != NULL)
methods = deref->struct_type()->methods();
else
methods = NULL;
Type* ptr_tdt = Pointer_type::make_pointer_type_descriptor_type();
const Struct_field_list* fields = ptr_tdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(2);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_PTR,
name, methods, false));
++p;
go_assert(p->is_field_name("elem"));
vals->push_back(Expression::make_type_descriptor(deref, bloc));
return Expression::make_struct_composite_literal(ptr_tdt, vals, bloc);
}
}
// Reflection string.
void
Pointer_type::do_reflection(Gogo* gogo, std::string* ret) const
{
ret->push_back('*');
this->append_reflection(this->to_type_, gogo, ret);
}
// Export.
void
Pointer_type::do_export(Export* exp) const
{
exp->write_c_string("*");
if (this->is_unsafe_pointer_type())
exp->write_c_string("any");
else
exp->write_type(this->to_type_);
}
// Import.
Pointer_type*
Pointer_type::do_import(Import* imp)
{
imp->require_c_string("*");
if (imp->match_c_string("any"))
{
imp->advance(3);
return Type::make_pointer_type(Type::make_void_type());
}
Type* to = imp->read_type();
return Type::make_pointer_type(to);
}
// Cache of pointer types. Key is "to" type, value is pointer type
// that points to key.
Type::Pointer_type_table Type::pointer_types;
// A list of placeholder pointer types. We keep this so we can ensure
// they are finalized.
std::vector<Pointer_type*> Type::placeholder_pointers;
// Make a pointer type.
Pointer_type*
Type::make_pointer_type(Type* to_type)
{
Pointer_type_table::const_iterator p = pointer_types.find(to_type);
if (p != pointer_types.end())
return p->second;
Pointer_type* ret = new Pointer_type(to_type);
pointer_types[to_type] = ret;
return ret;
}
// This helper is invoked immediately after named types have been
// converted, to clean up any unresolved pointer types remaining in
// the pointer type cache.
//
// The motivation for this routine: occasionally the compiler creates
// some specific pointer type as part of a lowering operation (ex:
// pointer-to-void), then Type::backend_type_size() is invoked on the
// type (which creates a Btype placeholder for it), that placeholder
// passed somewhere along the line to the back end, but since there is
// no reference to the type in user code, there is never a call to
// Type::finish_backend for the type (hence the Btype remains as an
// unresolved placeholder). Calling this routine will clean up such
// instances.
void
Type::finish_pointer_types(Gogo* gogo)
{
// We don't use begin() and end() because it is possible to add new
// placeholder pointer types as we finalized existing ones.
for (size_t i = 0; i < Type::placeholder_pointers.size(); i++)
{
Pointer_type* pt = Type::placeholder_pointers[i];
Type_btypes::iterator tbti = Type::type_btypes.find(pt);
if (tbti != Type::type_btypes.end() && tbti->second.is_placeholder)
{
pt->finish_backend(gogo, tbti->second.btype);
tbti->second.is_placeholder = false;
}
}
}
// Class Nil_type.
// Get the backend representation of a nil type. FIXME: Is this ever
// actually called?
Btype*
Nil_type::do_get_backend(Gogo* gogo)
{
return gogo->backend()->pointer_type(gogo->backend()->void_type());
}
// Make the nil type.
Type*
Type::make_nil_type()
{
static Nil_type singleton_nil_type;
return &singleton_nil_type;
}
// The type of a function call which returns multiple values. This is
// really a struct, but we don't want to confuse a function call which
// returns a struct with a function call which returns multiple
// values.
class Call_multiple_result_type : public Type
{
public:
Call_multiple_result_type(Call_expression* call)
: Type(TYPE_CALL_MULTIPLE_RESULT),
call_(call)
{ }
protected:
bool
do_has_pointer() const
{ return false; }
bool
do_compare_is_identity(Gogo*)
{ return false; }
Btype*
do_get_backend(Gogo* gogo)
{
go_assert(saw_errors());
return gogo->backend()->error_type();
}
Expression*
do_type_descriptor(Gogo*, Named_type*)
{
go_assert(saw_errors());
return Expression::make_error(Linemap::unknown_location());
}
void
do_reflection(Gogo*, std::string*) const
{ go_assert(saw_errors()); }
void
do_mangled_name(Gogo*, std::string*) const
{ go_assert(saw_errors()); }
private:
// The expression being called.
Call_expression* call_;
};
// Make a call result type.
Type*
Type::make_call_multiple_result_type(Call_expression* call)
{
return new Call_multiple_result_type(call);
}
// Class Struct_field.
// Get the name of a field.
const std::string&
Struct_field::field_name() const
{
const std::string& name(this->typed_identifier_.name());
if (!name.empty())
return name;
else
{
// This is called during parsing, before anything is lowered, so
// we have to be pretty careful to avoid dereferencing an
// unknown type name.
Type* t = this->typed_identifier_.type();
Type* dt = t;
if (t->classification() == Type::TYPE_POINTER)
{
// Very ugly.
Pointer_type* ptype = static_cast<Pointer_type*>(t);
dt = ptype->points_to();
}
if (dt->forward_declaration_type() != NULL)
return dt->forward_declaration_type()->name();
else if (dt->named_type() != NULL)
{
// Note that this can be an alias name.
return dt->named_type()->name();
}
else if (t->is_error_type() || dt->is_error_type())
{
static const std::string error_string = "*error*";
return error_string;
}
else
{
// Avoid crashing in the erroneous case where T is named but
// DT is not.
go_assert(t != dt);
if (t->forward_declaration_type() != NULL)
return t->forward_declaration_type()->name();
else if (t->named_type() != NULL)
return t->named_type()->name();
else
go_unreachable();
}
}
}
// Return whether this field is named NAME.
bool
Struct_field::is_field_name(const std::string& name) const
{
const std::string& me(this->typed_identifier_.name());
if (!me.empty())
return me == name;
else
{
Type* t = this->typed_identifier_.type();
if (t->points_to() != NULL)
t = t->points_to();
Named_type* nt = t->named_type();
if (nt != NULL && nt->name() == name)
return true;
// This is a horrible hack caused by the fact that we don't pack
// the names of builtin types. FIXME.
if (!this->is_imported_
&& nt != NULL
&& nt->is_builtin()
&& nt->name() == Gogo::unpack_hidden_name(name))
return true;
return false;
}
}
// Return whether this field is an unexported field named NAME.
bool
Struct_field::is_unexported_field_name(Gogo* gogo,
const std::string& name) const
{
const std::string& field_name(this->field_name());
if (Gogo::is_hidden_name(field_name)
&& name == Gogo::unpack_hidden_name(field_name)
&& gogo->pack_hidden_name(name, false) != field_name)
return true;
// Check for the name of a builtin type. This is like the test in
// is_field_name, only there we return false if this->is_imported_,
// and here we return true.
if (this->is_imported_ && this->is_anonymous())
{
Type* t = this->typed_identifier_.type();
if (t->points_to() != NULL)
t = t->points_to();
Named_type* nt = t->named_type();
if (nt != NULL
&& nt->is_builtin()
&& nt->name() == Gogo::unpack_hidden_name(name))
return true;
}
return false;
}
// Return whether this field is an embedded built-in type.
bool
Struct_field::is_embedded_builtin(Gogo* gogo) const
{
const std::string& name(this->field_name());
// We know that a field is an embedded type if it is anonymous.
// We can decide if it is a built-in type by checking to see if it is
// registered globally under the field's name.
// This allows us to distinguish between embedded built-in types and
// embedded types that are aliases to built-in types.
return (this->is_anonymous()
&& !Gogo::is_hidden_name(name)
&& gogo->lookup_global(name.c_str()) != NULL);
}
// Class Struct_type.
// A hash table used to find identical unnamed structs so that they
// share method tables.
Struct_type::Identical_structs Struct_type::identical_structs;
// A hash table used to merge method sets for identical unnamed
// structs.
Struct_type::Struct_method_tables Struct_type::struct_method_tables;
// Traversal.
int
Struct_type::do_traverse(Traverse* traverse)
{
Struct_field_list* fields = this->fields_;
if (fields != NULL)
{
for (Struct_field_list::iterator p = fields->begin();
p != fields->end();
++p)
{
if (Type::traverse(p->type(), traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
return TRAVERSE_CONTINUE;
}
// Verify that the struct type is complete and valid.
bool
Struct_type::do_verify()
{
Struct_field_list* fields = this->fields_;
if (fields == NULL)
return true;
for (Struct_field_list::iterator p = fields->begin();
p != fields->end();
++p)
{
Type* t = p->type();
if (p->is_anonymous())
{
if ((t->named_type() != NULL && t->points_to() != NULL)
|| (t->named_type() == NULL && t->points_to() != NULL
&& t->points_to()->points_to() != NULL))
{
go_error_at(p->location(), "embedded type may not be a pointer");
p->set_type(Type::make_error_type());
}
else if (t->points_to() != NULL
&& t->points_to()->interface_type() != NULL)
{
go_error_at(p->location(),
"embedded type may not be pointer to interface");
p->set_type(Type::make_error_type());
}
}
}
return true;
}
// Whether this contains a pointer.
bool
Struct_type::do_has_pointer() const
{
const Struct_field_list* fields = this->fields();
if (fields == NULL)
return false;
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
if (p->type()->has_pointer())
return true;
}
return false;
}
// Whether this type is identical to T.
bool
Struct_type::is_identical(const Struct_type* t, Cmp_tags cmp_tags,
bool errors_are_identical) const
{
if (this->is_struct_incomparable_ != t->is_struct_incomparable_)
return false;
const Struct_field_list* fields1 = this->fields();
const Struct_field_list* fields2 = t->fields();
if (fields1 == NULL || fields2 == NULL)
return fields1 == fields2;
Struct_field_list::const_iterator pf2 = fields2->begin();
for (Struct_field_list::const_iterator pf1 = fields1->begin();
pf1 != fields1->end();
++pf1, ++pf2)
{
if (pf2 == fields2->end())
return false;
if (pf1->field_name() != pf2->field_name())
return false;
if (pf1->is_anonymous() != pf2->is_anonymous()
|| !Type::are_identical_cmp_tags(pf1->type(), pf2->type(), cmp_tags,
errors_are_identical, NULL))
return false;
if (cmp_tags == COMPARE_TAGS)
{
if (!pf1->has_tag())
{
if (pf2->has_tag())
return false;
}
else
{
if (!pf2->has_tag())
return false;
if (pf1->tag() != pf2->tag())
return false;
}
}
}
if (pf2 != fields2->end())
return false;
return true;
}
// Whether comparisons of this struct type are simple identity
// comparisons.
bool
Struct_type::do_compare_is_identity(Gogo* gogo)
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return true;
int64_t offset = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (Gogo::is_sink_name(pf->field_name()))
return false;
if (!pf->type()->compare_is_identity(gogo))
return false;
int64_t field_align;
if (!pf->type()->backend_type_align(gogo, &field_align))
return false;
if ((offset & (field_align - 1)) != 0)
{
// This struct has padding. We don't guarantee that that
// padding is zero-initialized for a stack variable, so we
// can't use memcmp to compare struct values.
return false;
}
int64_t field_size;
if (!pf->type()->backend_type_size(gogo, &field_size))
return false;
offset += field_size;
}
int64_t struct_size;
if (!this->backend_type_size(gogo, &struct_size))
return false;
if (offset != struct_size)
{
// Trailing padding may not be zero when on the stack.
return false;
}
return true;
}
// Return whether this struct type is reflexive--whether a value of
// this type is always equal to itself.
bool
Struct_type::do_is_reflexive()
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return true;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (!pf->type()->is_reflexive())
return false;
}
return true;
}
// Return whether this struct type needs a key update when used as a
// map key.
bool
Struct_type::do_needs_key_update()
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return false;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (pf->type()->needs_key_update())
return true;
}
return false;
}
// Return whether this struct type is permitted to be in the heap.
bool
Struct_type::do_in_heap()
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return true;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (!pf->type()->in_heap())
return false;
}
return true;
}
// Build identity and hash functions for this struct.
// Hash code.
unsigned int
Struct_type::do_hash_for_method(Gogo* gogo) const
{
unsigned int ret = 0;
if (this->fields() != NULL)
{
for (Struct_field_list::const_iterator pf = this->fields()->begin();
pf != this->fields()->end();
++pf)
ret = (ret << 1) + pf->type()->hash_for_method(gogo);
}
ret <<= 2;
if (this->is_struct_incomparable_)
ret <<= 1;
return ret;
}
// Find the local field NAME.
const Struct_field*
Struct_type::find_local_field(const std::string& name,
unsigned int *pindex) const
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return NULL;
unsigned int i = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf, ++i)
{
if (pf->is_field_name(name))
{
if (pindex != NULL)
*pindex = i;
return &*pf;
}
}
return NULL;
}
// Return an expression for field NAME in STRUCT_EXPR, or NULL.
Field_reference_expression*
Struct_type::field_reference(Expression* struct_expr, const std::string& name,
Location location) const
{
unsigned int depth;
return this->field_reference_depth(struct_expr, name, location, NULL,
&depth);
}
// Return an expression for a field, along with the depth at which it
// was found.
Field_reference_expression*
Struct_type::field_reference_depth(Expression* struct_expr,
const std::string& name,
Location location,
Saw_named_type* saw,
unsigned int* depth) const
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL)
return NULL;
// Look for a field with this name.
unsigned int i = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf, ++i)
{
if (pf->is_field_name(name))
{
*depth = 0;
return Expression::make_field_reference(struct_expr, i, location);
}
}
// Look for an anonymous field which contains a field with this
// name.
unsigned int found_depth = 0;
Field_reference_expression* ret = NULL;
i = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf, ++i)
{
if (!pf->is_anonymous())
continue;
Struct_type* st = pf->type()->deref()->struct_type();
if (st == NULL)
continue;
Saw_named_type* hold_saw = saw;
Saw_named_type saw_here;
Named_type* nt = pf->type()->named_type();
if (nt == NULL)
nt = pf->type()->deref()->named_type();
if (nt != NULL)
{
Saw_named_type* q;
for (q = saw; q != NULL; q = q->next)
{
if (q->nt == nt)
{
// If this is an error, it will be reported
// elsewhere.
break;
}
}
if (q != NULL)
continue;
saw_here.next = saw;
saw_here.nt = nt;
saw = &saw_here;
}
// Look for a reference using a NULL struct expression. If we
// find one, fill in the struct expression with a reference to
// this field.
unsigned int subdepth;
Field_reference_expression* sub = st->field_reference_depth(NULL, name,
location,
saw,
&subdepth);
saw = hold_saw;
if (sub == NULL)
continue;
if (ret == NULL || subdepth < found_depth)
{
if (ret != NULL)
delete ret;
ret = sub;
found_depth = subdepth;
Expression* here = Expression::make_field_reference(struct_expr, i,
location);
if (pf->type()->points_to() != NULL)
here = Expression::make_dereference(here,
Expression::NIL_CHECK_DEFAULT,
location);
while (sub->expr() != NULL)
{
sub = sub->expr()->deref()->field_reference_expression();
go_assert(sub != NULL);
}
sub->set_struct_expression(here);
sub->set_implicit(true);
}
else if (subdepth > found_depth)
delete sub;
else
{
// We do not handle ambiguity here--it should be handled by
// Type::bind_field_or_method.
delete sub;
found_depth = 0;
ret = NULL;
}
}
if (ret != NULL)
*depth = found_depth + 1;
return ret;
}
// Return the total number of fields, including embedded fields.
unsigned int
Struct_type::total_field_count() const
{
if (this->fields_ == NULL)
return 0;
unsigned int ret = 0;
for (Struct_field_list::const_iterator pf = this->fields_->begin();
pf != this->fields_->end();
++pf)
{
if (!pf->is_anonymous() || pf->type()->struct_type() == NULL)
++ret;
else
ret += pf->type()->struct_type()->total_field_count();
}
return ret;
}
// Return whether NAME is an unexported field, for better error reporting.
bool
Struct_type::is_unexported_local_field(Gogo* gogo,
const std::string& name) const
{
const Struct_field_list* fields = this->fields_;
if (fields != NULL)
{
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
if (pf->is_unexported_field_name(gogo, name))
return true;
}
return false;
}
// Finalize the methods of an unnamed struct.
void
Struct_type::finalize_methods(Gogo* gogo)
{
if (this->all_methods_ != NULL)
return;
// It is possible to have multiple identical structs that have
// methods. We want them to share method tables. Otherwise we will
// emit identical methods more than once, which is bad since they
// will even have the same names.
std::pair<Identical_structs::iterator, bool> ins =
Struct_type::identical_structs.insert(std::make_pair(this, this));
if (!ins.second)
{
// An identical struct was already entered into the hash table.
// Note that finalize_methods is, fortunately, not recursive.
this->all_methods_ = ins.first->second->all_methods_;
return;
}
Type::finalize_methods(gogo, this, this->location_, &this->all_methods_);
}
// Return the method NAME, or NULL if there isn't one or if it is
// ambiguous. Set *IS_AMBIGUOUS if the method exists but is
// ambiguous.
Method*
Struct_type::method_function(const std::string& name, bool* is_ambiguous) const
{
return Type::method_function(this->all_methods_, name, is_ambiguous);
}
// Return a pointer to the interface method table for this type for
// the interface INTERFACE. IS_POINTER is true if this is for a
// pointer to THIS.
Expression*
Struct_type::interface_method_table(Interface_type* interface,
bool is_pointer)
{
std::pair<Struct_type*, Struct_type::Struct_method_table_pair*>
val(this, NULL);
std::pair<Struct_type::Struct_method_tables::iterator, bool> ins =
Struct_type::struct_method_tables.insert(val);
Struct_method_table_pair* smtp;
if (!ins.second)
smtp = ins.first->second;
else
{
smtp = new Struct_method_table_pair();
smtp->first = NULL;
smtp->second = NULL;
ins.first->second = smtp;
}
return Type::interface_method_table(this, interface, is_pointer,
&smtp->first, &smtp->second);
}
// Convert struct fields to the backend representation. This is not
// declared in types.h so that types.h doesn't have to #include
// backend.h.
static void
get_backend_struct_fields(Gogo* gogo, const Struct_field_list* fields,
bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields)
{
bfields->resize(fields->size());
size_t i = 0;
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p, ++i)
{
(*bfields)[i].name = Gogo::unpack_hidden_name(p->field_name());
(*bfields)[i].btype = (use_placeholder
? p->type()->get_backend_placeholder(gogo)
: p->type()->get_backend(gogo));
(*bfields)[i].location = p->location();
}
go_assert(i == fields->size());
}
// Get the backend representation for a struct type.
Btype*
Struct_type::do_get_backend(Gogo* gogo)
{
std::vector<Backend::Btyped_identifier> bfields;
get_backend_struct_fields(gogo, this->fields_, false, &bfields);
return gogo->backend()->struct_type(bfields);
}
// Finish the backend representation of the fields of a struct.
void
Struct_type::finish_backend_fields(Gogo* gogo)
{
const Struct_field_list* fields = this->fields_;
if (fields != NULL)
{
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
p->type()->get_backend(gogo);
}
}
// The type of a struct type descriptor.
Type*
Struct_type::make_struct_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* string_type = Type::lookup_string_type();
Type* pointer_string_type = Type::make_pointer_type(string_type);
Struct_type* sf =
Type::make_builtin_struct_type(5,
"name", pointer_string_type,
"pkgPath", pointer_string_type,
"typ", ptdt,
"tag", pointer_string_type,
"offsetAnon", uintptr_type);
Type* nsf = Type::make_builtin_named_type("structField", sf);
Type* slice_type = Type::make_array_type(nsf, NULL);
Struct_type* s = Type::make_builtin_struct_type(2,
"", tdt,
"fields", slice_type);
ret = Type::make_builtin_named_type("StructType", s);
}
return ret;
}
// Build a type descriptor for a struct type.
Expression*
Struct_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* stdt = Struct_type::make_struct_type_descriptor_type();
const Struct_field_list* fields = stdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(2);
const Methods* methods = this->methods();
// A named struct should not have methods--the methods should attach
// to the named type.
go_assert(methods == NULL || name == NULL);
Struct_field_list::const_iterator ps = fields->begin();
go_assert(ps->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_STRUCT,
name, methods, true));
++ps;
go_assert(ps->is_field_name("fields"));
Expression_list* elements = new Expression_list();
elements->reserve(this->fields_->size());
Type* element_type = ps->type()->array_type()->element_type();
for (Struct_field_list::const_iterator pf = this->fields_->begin();
pf != this->fields_->end();
++pf)
{
const Struct_field_list* f = element_type->struct_type()->fields();
Expression_list* fvals = new Expression_list();
fvals->reserve(5);
Struct_field_list::const_iterator q = f->begin();
go_assert(q->is_field_name("name"));
std::string n = Gogo::unpack_hidden_name(pf->field_name());
Expression* s = Expression::make_string(n, bloc);
fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
++q;
go_assert(q->is_field_name("pkgPath"));
bool is_embedded_builtin = pf->is_embedded_builtin(gogo);
if (!Gogo::is_hidden_name(pf->field_name()) && !is_embedded_builtin)
fvals->push_back(Expression::make_nil(bloc));
else
{
std::string n;
if (is_embedded_builtin)
n = gogo->package_name();
else
n = Gogo::hidden_name_pkgpath(pf->field_name());
Expression* s = Expression::make_string(n, bloc);
fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
}
++q;
go_assert(q->is_field_name("typ"));
fvals->push_back(Expression::make_type_descriptor(pf->type(), bloc));
++q;
go_assert(q->is_field_name("tag"));
if (!pf->has_tag())
fvals->push_back(Expression::make_nil(bloc));
else
{
Expression* s = Expression::make_string(pf->tag(), bloc);
fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc));
}
++q;
go_assert(q->is_field_name("offsetAnon"));
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Expression* o = Expression::make_struct_field_offset(this, &*pf);
Expression* one = Expression::make_integer_ul(1, uintptr_type, bloc);
o = Expression::make_binary(OPERATOR_LSHIFT, o, one, bloc);
int av = pf->is_anonymous() ? 1 : 0;
Expression* anon = Expression::make_integer_ul(av, uintptr_type, bloc);
o = Expression::make_binary(OPERATOR_OR, o, anon, bloc);
fvals->push_back(o);
Expression* v = Expression::make_struct_composite_literal(element_type,
fvals, bloc);
elements->push_back(v);
}
vals->push_back(Expression::make_slice_composite_literal(ps->type(),
elements, bloc));
return Expression::make_struct_composite_literal(stdt, vals, bloc);
}
// Write the hash function for a struct which can not use the identity
// function.
void
Struct_type::write_hash_function(Gogo* gogo, Named_type*,
Function_type* hash_fntype,
Function_type* equal_fntype)
{
Location bloc = Linemap::predeclared_location();
// The pointer to the struct that we are going to hash. This is an
// argument to the hash function we are implementing here.
Named_object* key_arg = gogo->lookup("key", NULL);
go_assert(key_arg != NULL);
Type* key_arg_type = key_arg->var_value()->type();
// The seed argument to the hash function.
Named_object* seed_arg = gogo->lookup("seed", NULL);
go_assert(seed_arg != NULL);
Type* uintptr_type = Type::lookup_integer_type("uintptr");
// Make a temporary to hold the return value, initialized to the seed.
Expression* ref = Expression::make_var_reference(seed_arg, bloc);
Temporary_statement* retval = Statement::make_temporary(uintptr_type, ref,
bloc);
gogo->add_statement(retval);
// Make a temporary to hold the key as a uintptr.
ref = Expression::make_var_reference(key_arg, bloc);
ref = Expression::make_cast(uintptr_type, ref, bloc);
Temporary_statement* key = Statement::make_temporary(uintptr_type, ref,
bloc);
gogo->add_statement(key);
// Loop over the struct fields.
const Struct_field_list* fields = this->fields_;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (Gogo::is_sink_name(pf->field_name()))
continue;
// Get a pointer to the value of this field.
Expression* offset = Expression::make_struct_field_offset(this, &*pf);
ref = Expression::make_temporary_reference(key, bloc);
Expression* subkey = Expression::make_binary(OPERATOR_PLUS, ref, offset,
bloc);
subkey = Expression::make_cast(key_arg_type, subkey, bloc);
// Get the hash function to use for the type of this field.
Named_object* hash_fn;
Named_object* equal_fn;
pf->type()->type_functions(gogo, pf->type()->named_type(), hash_fntype,
equal_fntype, &hash_fn, &equal_fn);
// Call the hash function for the field, passing retval as the seed.
ref = Expression::make_temporary_reference(retval, bloc);
Expression_list* args = new Expression_list();
args->push_back(subkey);
args->push_back(ref);
Expression* func = Expression::make_func_reference(hash_fn, NULL, bloc);
Expression* call = Expression::make_call(func, args, false, bloc);
// Set retval to the result.
Temporary_reference_expression* tref =
Expression::make_temporary_reference(retval, bloc);
tref->set_is_lvalue();
Statement* s = Statement::make_assignment(tref, call, bloc);
gogo->add_statement(s);
}
// Return retval to the caller of the hash function.
Expression_list* vals = new Expression_list();
ref = Expression::make_temporary_reference(retval, bloc);
vals->push_back(ref);
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Write the equality function for a struct which can not use the
// identity function.
void
Struct_type::write_equal_function(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
// The pointers to the structs we are going to compare.
Named_object* key1_arg = gogo->lookup("key1", NULL);
Named_object* key2_arg = gogo->lookup("key2", NULL);
go_assert(key1_arg != NULL && key2_arg != NULL);
// Build temporaries with the right types.
Type* pt = Type::make_pointer_type(name != NULL
? static_cast<Type*>(name)
: static_cast<Type*>(this));
Expression* ref = Expression::make_var_reference(key1_arg, bloc);
ref = Expression::make_unsafe_cast(pt, ref, bloc);
Temporary_statement* p1 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p1);
ref = Expression::make_var_reference(key2_arg, bloc);
ref = Expression::make_unsafe_cast(pt, ref, bloc);
Temporary_statement* p2 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p2);
const Struct_field_list* fields = this->fields_;
unsigned int field_index = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf, ++field_index)
{
if (Gogo::is_sink_name(pf->field_name()))
continue;
// Compare one field in both P1 and P2.
Expression* f1 = Expression::make_temporary_reference(p1, bloc);
f1 = Expression::make_dereference(f1, Expression::NIL_CHECK_DEFAULT,
bloc);
f1 = Expression::make_field_reference(f1, field_index, bloc);
Expression* f2 = Expression::make_temporary_reference(p2, bloc);
f2 = Expression::make_dereference(f2, Expression::NIL_CHECK_DEFAULT,
bloc);
f2 = Expression::make_field_reference(f2, field_index, bloc);
Expression* cond = Expression::make_binary(OPERATOR_NOTEQ, f1, f2, bloc);
// If the values are not equal, return false.
gogo->start_block(bloc);
Expression_list* vals = new Expression_list();
vals->push_back(Expression::make_boolean(false, bloc));
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
Block* then_block = gogo->finish_block(bloc);
s = Statement::make_if_statement(cond, then_block, NULL, bloc);
gogo->add_statement(s);
}
// All the fields are equal, so return true.
Expression_list* vals = new Expression_list();
vals->push_back(Expression::make_boolean(true, bloc));
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Reflection string.
void
Struct_type::do_reflection(Gogo* gogo, std::string* ret) const
{
ret->append("struct {");
for (Struct_field_list::const_iterator p = this->fields_->begin();
p != this->fields_->end();
++p)
{
if (p != this->fields_->begin())
ret->push_back(';');
ret->push_back(' ');
if (!p->is_anonymous())
{
ret->append(Gogo::unpack_hidden_name(p->field_name()));
ret->push_back(' ');
}
if (p->is_anonymous()
&& p->type()->named_type() != NULL
&& p->type()->named_type()->is_alias())
p->type()->named_type()->append_reflection_type_name(gogo, true, ret);
else
this->append_reflection(p->type(), gogo, ret);
if (p->has_tag())
{
const std::string& tag(p->tag());
ret->append(" \"");
for (std::string::const_iterator p = tag.begin();
p != tag.end();
++p)
{
if (*p == '\0')
ret->append("\\x00");
else if (*p == '\n')
ret->append("\\n");
else if (*p == '\t')
ret->append("\\t");
else if (*p == '"')
ret->append("\\\"");
else if (*p == '\\')
ret->append("\\\\");
else
ret->push_back(*p);
}
ret->push_back('"');
}
}
if (!this->fields_->empty())
ret->push_back(' ');
ret->push_back('}');
}
// If the offset of field INDEX in the backend implementation can be
// determined, set *POFFSET to the offset in bytes and return true.
// Otherwise, return false.
bool
Struct_type::backend_field_offset(Gogo* gogo, unsigned int index,
int64_t* poffset)
{
if (!this->is_backend_type_size_known(gogo))
return false;
Btype* bt = this->get_backend_placeholder(gogo);
*poffset = gogo->backend()->type_field_offset(bt, index);
return true;
}
// Export.
void
Struct_type::do_export(Export* exp) const
{
exp->write_c_string("struct { ");
const Struct_field_list* fields = this->fields_;
go_assert(fields != NULL);
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
if (p->is_anonymous())
exp->write_string("? ");
else
{
exp->write_string(p->field_name());
exp->write_c_string(" ");
}
exp->write_type(p->type());
if (p->has_tag())
{
exp->write_c_string(" ");
Expression* expr =
Expression::make_string(p->tag(), Linemap::predeclared_location());
expr->export_expression(exp);
delete expr;
}
exp->write_c_string("; ");
}
exp->write_c_string("}");
}
// Import.
Struct_type*
Struct_type::do_import(Import* imp)
{
imp->require_c_string("struct { ");
Struct_field_list* fields = new Struct_field_list;
if (imp->peek_char() != '}')
{
while (true)
{
std::string name;
if (imp->match_c_string("? "))
imp->advance(2);
else
{
name = imp->read_identifier();
imp->require_c_string(" ");
}
Type* ftype = imp->read_type();
Struct_field sf(Typed_identifier(name, ftype, imp->location()));
sf.set_is_imported();
if (imp->peek_char() == ' ')
{
imp->advance(1);
Expression* expr = Expression::import_expression(imp);
String_expression* sexpr = expr->string_expression();
go_assert(sexpr != NULL);
sf.set_tag(sexpr->val());
delete sexpr;
}
imp->require_c_string("; ");
fields->push_back(sf);
if (imp->peek_char() == '}')
break;
}
}
imp->require_c_string("}");
return Type::make_struct_type(fields, imp->location());
}
// Whether we can write this struct type to a C header file.
// We can't if any of the fields are structs defined in a different package.
bool
Struct_type::can_write_to_c_header(
std::vector<const Named_object*>* requires,
std::vector<const Named_object*>* declare) const
{
const Struct_field_list* fields = this->fields_;
if (fields == NULL || fields->empty())
return false;
int sinks = 0;
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
if (p->is_anonymous())
return false;
if (!this->can_write_type_to_c_header(p->type(), requires, declare))
return false;
if (Gogo::message_name(p->field_name()) == "_")
sinks++;
}
if (sinks > 1)
return false;
return true;
}
// Whether we can write the type T to a C header file.
bool
Struct_type::can_write_type_to_c_header(
const Type* t,
std::vector<const Named_object*>* requires,
std::vector<const Named_object*>* declare) const
{
t = t->forwarded();
switch (t->classification())
{
case TYPE_ERROR:
case TYPE_FORWARD:
return false;
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_FUNCTION:
case TYPE_MAP:
case TYPE_CHANNEL:
case TYPE_INTERFACE:
return true;
case TYPE_POINTER:
// Don't try to handle a pointer to an array.
if (t->points_to()->array_type() != NULL
&& !t->points_to()->is_slice_type())
return false;
if (t->points_to()->named_type() != NULL
&& t->points_to()->struct_type() != NULL)
declare->push_back(t->points_to()->named_type()->named_object());
return true;
case TYPE_STRUCT:
return t->struct_type()->can_write_to_c_header(requires, declare);
case TYPE_ARRAY:
if (t->is_slice_type())
return true;
return this->can_write_type_to_c_header(t->array_type()->element_type(),
requires, declare);
case TYPE_NAMED:
{
const Named_object* no = t->named_type()->named_object();
if (no->package() != NULL)
{
if (t->is_unsafe_pointer_type())
return true;
return false;
}
if (t->struct_type() != NULL)
{
requires->push_back(no);
return t->struct_type()->can_write_to_c_header(requires, declare);
}
return this->can_write_type_to_c_header(t->base(), requires, declare);
}
case TYPE_CALL_MULTIPLE_RESULT:
case TYPE_NIL:
case TYPE_SINK:
default:
go_unreachable();
}
}
// Write this struct to a C header file.
void
Struct_type::write_to_c_header(std::ostream& os) const
{
const Struct_field_list* fields = this->fields_;
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
os << '\t';
this->write_field_to_c_header(os, p->field_name(), p->type());
os << ';' << std::endl;
}
}
// Write the type of a struct field to a C header file.
void
Struct_type::write_field_to_c_header(std::ostream& os, const std::string& name,
const Type *t) const
{
bool print_name = true;
t = t->forwarded();
switch (t->classification())
{
case TYPE_VOID:
os << "void";
break;
case TYPE_BOOLEAN:
os << "_Bool";
break;
case TYPE_INTEGER:
{
const Integer_type* it = t->integer_type();
if (it->is_unsigned())
os << 'u';
os << "int" << it->bits() << "_t";
}
break;
case TYPE_FLOAT:
switch (t->float_type()->bits())
{
case 32:
os << "float";
break;
case 64:
os << "double";
break;
default:
go_unreachable();
}
break;
case TYPE_COMPLEX:
switch (t->complex_type()->bits())
{
case 64:
os << "float _Complex";
break;
case 128:
os << "double _Complex";
break;
default:
go_unreachable();
}
break;
case TYPE_STRING:
os << "String";
break;
case TYPE_FUNCTION:
os << "FuncVal*";
break;
case TYPE_POINTER:
{
std::vector<const Named_object*> requires;
std::vector<const Named_object*> declare;
if (!this->can_write_type_to_c_header(t->points_to(), &requires,
&declare))
os << "void*";
else
{
this->write_field_to_c_header(os, "", t->points_to());
os << '*';
}
}
break;
case TYPE_MAP:
os << "Map*";
break;
case TYPE_CHANNEL:
os << "Chan*";
break;
case TYPE_INTERFACE:
if (t->interface_type()->is_empty())
os << "Eface";
else
os << "Iface";
break;
case TYPE_STRUCT:
os << "struct {" << std::endl;
t->struct_type()->write_to_c_header(os);
os << "\t}";
break;
case TYPE_ARRAY:
if (t->is_slice_type())
os << "Slice";
else
{
const Type *ele = t;
std::vector<const Type*> array_types;
while (ele->array_type() != NULL && !ele->is_slice_type())
{
array_types.push_back(ele);
ele = ele->array_type()->element_type();
}
this->write_field_to_c_header(os, "", ele);
os << ' ' << Gogo::message_name(name);
print_name = false;
while (!array_types.empty())
{
ele = array_types.back();
array_types.pop_back();
os << '[';
Numeric_constant nc;
if (!ele->array_type()->length()->numeric_constant_value(&nc))
go_unreachable();
mpz_t val;
if (!nc.to_int(&val))
go_unreachable();
char* s = mpz_get_str(NULL, 10, val);
os << s;
free(s);
mpz_clear(val);
os << ']';
}
}
break;
case TYPE_NAMED:
{
const Named_object* no = t->named_type()->named_object();
if (t->struct_type() != NULL)
os << "struct " << no->message_name();
else if (t->is_unsafe_pointer_type())
os << "void*";
else if (t == Type::lookup_integer_type("uintptr"))
os << "uintptr_t";
else
{
this->write_field_to_c_header(os, name, t->base());
print_name = false;
}
}
break;
case TYPE_ERROR:
case TYPE_FORWARD:
case TYPE_CALL_MULTIPLE_RESULT:
case TYPE_NIL:
case TYPE_SINK:
default:
go_unreachable();
}
if (print_name && !name.empty())
os << ' ' << Gogo::message_name(name);
}
// Make a struct type.
Struct_type*
Type::make_struct_type(Struct_field_list* fields,
Location location)
{
return new Struct_type(fields, location);
}
// Class Array_type.
// Store the length of an array as an int64_t into *PLEN. Return
// false if the length can not be determined. This will assert if
// called for a slice.
bool
Array_type::int_length(int64_t* plen)
{
go_assert(this->length_ != NULL);
Numeric_constant nc;
if (!this->length_->numeric_constant_value(&nc))
return false;
return nc.to_memory_size(plen);
}
// Whether two array types are identical.
bool
Array_type::is_identical(const Array_type* t, Cmp_tags cmp_tags,
bool errors_are_identical) const
{
if (!Type::are_identical_cmp_tags(this->element_type(), t->element_type(),
cmp_tags, errors_are_identical, NULL))
return false;
if (this->is_array_incomparable_ != t->is_array_incomparable_)
return false;
Expression* l1 = this->length();
Expression* l2 = t->length();
// Slices of the same element type are identical.
if (l1 == NULL && l2 == NULL)
return true;
// Arrays of the same element type are identical if they have the
// same length.
if (l1 != NULL && l2 != NULL)
{
if (l1 == l2)
return true;
// Try to determine the lengths. If we can't, assume the arrays
// are not identical.
bool ret = false;
Numeric_constant nc1, nc2;
if (l1->numeric_constant_value(&nc1)
&& l2->numeric_constant_value(&nc2))
{
mpz_t v1;
if (nc1.to_int(&v1))
{
mpz_t v2;
if (nc2.to_int(&v2))
{
ret = mpz_cmp(v1, v2) == 0;
mpz_clear(v2);
}
mpz_clear(v1);
}
}
return ret;
}
// Otherwise the arrays are not identical.
return false;
}
// Traversal.
int
Array_type::do_traverse(Traverse* traverse)
{
if (Type::traverse(this->element_type_, traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
if (this->length_ != NULL
&& Expression::traverse(&this->length_, traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
return TRAVERSE_CONTINUE;
}
// Check that the length is valid.
bool
Array_type::verify_length()
{
if (this->length_ == NULL)
return true;
Type_context context(Type::lookup_integer_type("int"), false);
this->length_->determine_type(&context);
if (!this->length_->is_constant())
{
go_error_at(this->length_->location(), "array bound is not constant");
return false;
}
// For array types, the length expression can be an untyped constant
// representable as an int, but we don't allow explicitly non-integer
// values such as "float64(10)". See issues #13485 and #13486.
if (this->length_->type()->integer_type() == NULL
&& !this->length_->type()->is_error_type())
{
go_error_at(this->length_->location(), "invalid array bound");
return false;
}
Numeric_constant nc;
if (!this->length_->numeric_constant_value(&nc))
{
if (this->length_->type()->integer_type() != NULL
|| this->length_->type()->float_type() != NULL)
go_error_at(this->length_->location(), "array bound is not constant");
else
go_error_at(this->length_->location(), "array bound is not numeric");
return false;
}
Type* int_type = Type::lookup_integer_type("int");
unsigned int tbits = int_type->integer_type()->bits();
unsigned long val;
switch (nc.to_unsigned_long(&val))
{
case Numeric_constant::NC_UL_VALID:
if (sizeof(val) >= tbits / 8 && val >> (tbits - 1) != 0)
{
go_error_at(this->length_->location(), "array bound overflows");
return false;
}
break;
case Numeric_constant::NC_UL_NOTINT:
go_error_at(this->length_->location(), "array bound truncated to integer");
return false;
case Numeric_constant::NC_UL_NEGATIVE:
go_error_at(this->length_->location(), "negative array bound");
return false;
case Numeric_constant::NC_UL_BIG:
{
mpz_t val;
if (!nc.to_int(&val))
go_unreachable();
unsigned int bits = mpz_sizeinbase(val, 2);
mpz_clear(val);
if (bits >= tbits)
{
go_error_at(this->length_->location(), "array bound overflows");
return false;
}
}
break;
default:
go_unreachable();
}
return true;
}
// Verify the type.
bool
Array_type::do_verify()
{
if (this->element_type()->is_error_type())
return false;
if (!this->verify_length())
this->length_ = Expression::make_error(this->length_->location());
return true;
}
// Whether the type contains pointers. This is always true for a
// slice. For an array it is true if the element type has pointers
// and the length is greater than zero.
bool
Array_type::do_has_pointer() const
{
if (this->length_ == NULL)
return true;
if (!this->element_type_->has_pointer())
return false;
Numeric_constant nc;
if (!this->length_->numeric_constant_value(&nc))
{
// Error reported elsewhere.
return false;
}
unsigned long val;
switch (nc.to_unsigned_long(&val))
{
case Numeric_constant::NC_UL_VALID:
return val > 0;
case Numeric_constant::NC_UL_BIG:
return true;
default:
// Error reported elsewhere.
return false;
}
}
// Whether we can use memcmp to compare this array.
bool
Array_type::do_compare_is_identity(Gogo* gogo)
{
if (this->length_ == NULL)
return false;
// Check for [...], which indicates that this is not a real type.
if (this->length_->is_nil_expression())
return false;
if (!this->element_type_->compare_is_identity(gogo))
return false;
// If there is any padding, then we can't use memcmp.
int64_t size;
int64_t align;
if (!this->element_type_->backend_type_size(gogo, &size)
|| !this->element_type_->backend_type_align(gogo, &align))
return false;
if ((size & (align - 1)) != 0)
return false;
return true;
}
// Array type hash code.
unsigned int
Array_type::do_hash_for_method(Gogo* gogo) const
{
unsigned int ret;
// There is no very convenient way to get a hash code for the
// length.
ret = this->element_type_->hash_for_method(gogo) + 1;
if (this->is_array_incomparable_)
ret <<= 1;
return ret;
}
// Write the hash function for an array which can not use the identify
// function.
void
Array_type::write_hash_function(Gogo* gogo, Named_type* name,
Function_type* hash_fntype,
Function_type* equal_fntype)
{
Location bloc = Linemap::predeclared_location();
// The pointer to the array that we are going to hash. This is an
// argument to the hash function we are implementing here.
Named_object* key_arg = gogo->lookup("key", NULL);
go_assert(key_arg != NULL);
Type* key_arg_type = key_arg->var_value()->type();
// The seed argument to the hash function.
Named_object* seed_arg = gogo->lookup("seed", NULL);
go_assert(seed_arg != NULL);
Type* uintptr_type = Type::lookup_integer_type("uintptr");
// Make a temporary to hold the return value, initialized to the seed.
Expression* ref = Expression::make_var_reference(seed_arg, bloc);
Temporary_statement* retval = Statement::make_temporary(uintptr_type, ref,
bloc);
gogo->add_statement(retval);
// Make a temporary to hold the key as a uintptr.
ref = Expression::make_var_reference(key_arg, bloc);
ref = Expression::make_cast(uintptr_type, ref, bloc);
Temporary_statement* key = Statement::make_temporary(uintptr_type, ref,
bloc);
gogo->add_statement(key);
// Loop over the array elements.
// for i = range a
Type* int_type = Type::lookup_integer_type("int");
Temporary_statement* index = Statement::make_temporary(int_type, NULL, bloc);
gogo->add_statement(index);
Expression* iref = Expression::make_temporary_reference(index, bloc);
Expression* aref = Expression::make_var_reference(key_arg, bloc);
Type* pt = Type::make_pointer_type(name != NULL
? static_cast<Type*>(name)
: static_cast<Type*>(this));
aref = Expression::make_cast(pt, aref, bloc);
For_range_statement* for_range = Statement::make_for_range_statement(iref,
NULL,
aref,
bloc);
gogo->start_block(bloc);
// Get the hash function for the element type.
Named_object* hash_fn;
Named_object* equal_fn;
this->element_type_->type_functions(gogo, this->element_type_->named_type(),
hash_fntype, equal_fntype, &hash_fn,
&equal_fn);
// Get a pointer to this element in the loop.
Expression* subkey = Expression::make_temporary_reference(key, bloc);
subkey = Expression::make_cast(key_arg_type, subkey, bloc);
// Get the size of each element.
Expression* ele_size = Expression::make_type_info(this->element_type_,
Expression::TYPE_INFO_SIZE);
// Get the hash of this element, passing retval as the seed.
ref = Expression::make_temporary_reference(retval, bloc);
Expression_list* args = new Expression_list();
args->push_back(subkey);
args->push_back(ref);
Expression* func = Expression::make_func_reference(hash_fn, NULL, bloc);
Expression* call = Expression::make_call(func, args, false, bloc);
// Set retval to the result.
Temporary_reference_expression* tref =
Expression::make_temporary_reference(retval, bloc);
tref->set_is_lvalue();
Statement* s = Statement::make_assignment(tref, call, bloc);
gogo->add_statement(s);
// Increase the element pointer.
tref = Expression::make_temporary_reference(key, bloc);
tref->set_is_lvalue();
s = Statement::make_assignment_operation(OPERATOR_PLUSEQ, tref, ele_size,
bloc);
Block* statements = gogo->finish_block(bloc);
for_range->add_statements(statements);
gogo->add_statement(for_range);
// Return retval to the caller of the hash function.
Expression_list* vals = new Expression_list();
ref = Expression::make_temporary_reference(retval, bloc);
vals->push_back(ref);
s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Write the equality function for an array which can not use the
// identity function.
void
Array_type::write_equal_function(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
// The pointers to the arrays we are going to compare.
Named_object* key1_arg = gogo->lookup("key1", NULL);
Named_object* key2_arg = gogo->lookup("key2", NULL);
go_assert(key1_arg != NULL && key2_arg != NULL);
// Build temporaries for the keys with the right types.
Type* pt = Type::make_pointer_type(name != NULL
? static_cast<Type*>(name)
: static_cast<Type*>(this));
Expression* ref = Expression::make_var_reference(key1_arg, bloc);
ref = Expression::make_unsafe_cast(pt, ref, bloc);
Temporary_statement* p1 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p1);
ref = Expression::make_var_reference(key2_arg, bloc);
ref = Expression::make_unsafe_cast(pt, ref, bloc);
Temporary_statement* p2 = Statement::make_temporary(pt, ref, bloc);
gogo->add_statement(p2);
// Loop over the array elements.
// for i = range a
Type* int_type = Type::lookup_integer_type("int");
Temporary_statement* index = Statement::make_temporary(int_type, NULL, bloc);
gogo->add_statement(index);
Expression* iref = Expression::make_temporary_reference(index, bloc);
Expression* aref = Expression::make_temporary_reference(p1, bloc);
For_range_statement* for_range = Statement::make_for_range_statement(iref,
NULL,
aref,
bloc);
gogo->start_block(bloc);
// Compare element in P1 and P2.
Expression* e1 = Expression::make_temporary_reference(p1, bloc);
e1 = Expression::make_dereference(e1, Expression::NIL_CHECK_DEFAULT, bloc);
ref = Expression::make_temporary_reference(index, bloc);
e1 = Expression::make_array_index(e1, ref, NULL, NULL, bloc);
Expression* e2 = Expression::make_temporary_reference(p2, bloc);
e2 = Expression::make_dereference(e2, Expression::NIL_CHECK_DEFAULT, bloc);
ref = Expression::make_temporary_reference(index, bloc);
e2 = Expression::make_array_index(e2, ref, NULL, NULL, bloc);
Expression* cond = Expression::make_binary(OPERATOR_NOTEQ, e1, e2, bloc);
// If the elements are not equal, return false.
gogo->start_block(bloc);
Expression_list* vals = new Expression_list();
vals->push_back(Expression::make_boolean(false, bloc));
Statement* s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
Block* then_block = gogo->finish_block(bloc);
s = Statement::make_if_statement(cond, then_block, NULL, bloc);
gogo->add_statement(s);
Block* statements = gogo->finish_block(bloc);
for_range->add_statements(statements);
gogo->add_statement(for_range);
// All the elements are equal, so return true.
vals = new Expression_list();
vals->push_back(Expression::make_boolean(true, bloc));
s = Statement::make_return_statement(vals, bloc);
gogo->add_statement(s);
}
// Get the backend representation of the fields of a slice. This is
// not declared in types.h so that types.h doesn't have to #include
// backend.h.
//
// We use int for the count and capacity fields. This matches 6g.
// The language more or less assumes that we can't allocate space of a
// size which does not fit in int.
static void
get_backend_slice_fields(Gogo* gogo, Array_type* type, bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields)
{
bfields->resize(3);
Type* pet = Type::make_pointer_type(type->element_type());
Btype* pbet = (use_placeholder
? pet->get_backend_placeholder(gogo)
: pet->get_backend(gogo));
Location ploc = Linemap::predeclared_location();
Backend::Btyped_identifier* p = &(*bfields)[0];
p->name = "__values";
p->btype = pbet;
p->location = ploc;
Type* int_type = Type::lookup_integer_type("int");
p = &(*bfields)[1];
p->name = "__count";
p->btype = int_type->get_backend(gogo);
p->location = ploc;
p = &(*bfields)[2];
p->name = "__capacity";
p->btype = int_type->get_backend(gogo);
p->location = ploc;
}
// Get the backend representation for the type of this array. A fixed array is
// simply represented as ARRAY_TYPE with the appropriate index--i.e., it is
// just like an array in C. An open array is a struct with three
// fields: a data pointer, the length, and the capacity.
Btype*
Array_type::do_get_backend(Gogo* gogo)
{
if (this->length_ == NULL)
{
std::vector<Backend::Btyped_identifier> bfields;
get_backend_slice_fields(gogo, this, false, &bfields);
return gogo->backend()->struct_type(bfields);
}
else
{
Btype* element = this->get_backend_element(gogo, false);
Bexpression* len = this->get_backend_length(gogo);
return gogo->backend()->array_type(element, len);
}
}
// Return the backend representation of the element type.
Btype*
Array_type::get_backend_element(Gogo* gogo, bool use_placeholder)
{
if (use_placeholder)
return this->element_type_->get_backend_placeholder(gogo);
else
return this->element_type_->get_backend(gogo);
}
// Return the backend representation of the length. The length may be
// computed using a function call, so we must only evaluate it once.
Bexpression*
Array_type::get_backend_length(Gogo* gogo)
{
go_assert(this->length_ != NULL);
if (this->blength_ == NULL)
{
if (this->length_->is_error_expression())
{
this->blength_ = gogo->backend()->error_expression();
return this->blength_;
}
Numeric_constant nc;
mpz_t val;
if (this->length_->numeric_constant_value(&nc) && nc.to_int(&val))
{
if (mpz_sgn(val) < 0)
{
this->blength_ = gogo->backend()->error_expression();
return this->blength_;
}
Type* t = nc.type();
if (t == NULL)
t = Type::lookup_integer_type("int");
else if (t->is_abstract())
t = t->make_non_abstract_type();
Btype* btype = t->get_backend(gogo);
this->blength_ =
gogo->backend()->integer_constant_expression(btype, val);
mpz_clear(val);
}
else
{
// Make up a translation context for the array length
// expression. FIXME: This won't work in general.
Translate_context context(gogo, NULL, NULL, NULL);
this->blength_ = this->length_->get_backend(&context);
Btype* ibtype = Type::lookup_integer_type("int")->get_backend(gogo);
this->blength_ =
gogo->backend()->convert_expression(ibtype, this->blength_,
this->length_->location());
}
}
return this->blength_;
}
// Finish backend representation of the array.
void
Array_type::finish_backend_element(Gogo* gogo)
{
Type* et = this->array_type()->element_type();
et->get_backend(gogo);
if (this->is_slice_type())
{
// This relies on the fact that we always use the same
// structure for a pointer to any given type.
Type* pet = Type::make_pointer_type(et);
pet->get_backend(gogo);
}
}
// Return an expression for a pointer to the values in ARRAY.
Expression*
Array_type::get_value_pointer(Gogo*, Expression* array, bool is_lvalue) const
{
if (this->length() != NULL)
{
// Fixed array.
go_assert(array->type()->array_type() != NULL);
Type* etype = array->type()->array_type()->element_type();
array = Expression::make_unary(OPERATOR_AND, array, array->location());
return Expression::make_cast(Type::make_pointer_type(etype), array,
array->location());
}
// Slice.
if (is_lvalue)
{
Temporary_reference_expression* tref =
array->temporary_reference_expression();
Var_expression* ve = array->var_expression();
if (tref != NULL)
{
tref = tref->copy()->temporary_reference_expression();
tref->set_is_lvalue();
array = tref;
}
else if (ve != NULL)
{
ve = new Var_expression(ve->named_object(), ve->location());
array = ve;
}
}
return Expression::make_slice_info(array,
Expression::SLICE_INFO_VALUE_POINTER,
array->location());
}
// Return an expression for the length of the array ARRAY which has this
// type.
Expression*
Array_type::get_length(Gogo*, Expression* array) const
{
if (this->length_ != NULL)
return this->length_;
// This is a slice. We need to read the length field.
return Expression::make_slice_info(array, Expression::SLICE_INFO_LENGTH,
array->location());
}
// Return an expression for the capacity of the array ARRAY which has this
// type.
Expression*
Array_type::get_capacity(Gogo*, Expression* array) const
{
if (this->length_ != NULL)
return this->length_;
// This is a slice. We need to read the capacity field.
return Expression::make_slice_info(array, Expression::SLICE_INFO_CAPACITY,
array->location());
}
// Export.
void
Array_type::do_export(Export* exp) const
{
exp->write_c_string("[");
if (this->length_ != NULL)
this->length_->export_expression(exp);
exp->write_c_string("] ");
exp->write_type(this->element_type_);
}
// Import.
Array_type*
Array_type::do_import(Import* imp)
{
imp->require_c_string("[");
Expression* length;
if (imp->peek_char() == ']')
length = NULL;
else
length = Expression::import_expression(imp);
imp->require_c_string("] ");
Type* element_type = imp->read_type();
return Type::make_array_type(element_type, length);
}
// The type of an array type descriptor.
Type*
Array_type::make_array_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Struct_type* sf =
Type::make_builtin_struct_type(4,
"", tdt,
"elem", ptdt,
"slice", ptdt,
"len", uintptr_type);
ret = Type::make_builtin_named_type("ArrayType", sf);
}
return ret;
}
// The type of an slice type descriptor.
Type*
Array_type::make_slice_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Struct_type* sf =
Type::make_builtin_struct_type(2,
"", tdt,
"elem", ptdt);
ret = Type::make_builtin_named_type("SliceType", sf);
}
return ret;
}
// Build a type descriptor for an array/slice type.
Expression*
Array_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
if (this->length_ != NULL)
return this->array_type_descriptor(gogo, name);
else
return this->slice_type_descriptor(gogo, name);
}
// Build a type descriptor for an array type.
Expression*
Array_type::array_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* atdt = Array_type::make_array_type_descriptor_type();
const Struct_field_list* fields = atdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(3);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_ARRAY,
name, NULL, true));
++p;
go_assert(p->is_field_name("elem"));
vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc));
++p;
go_assert(p->is_field_name("slice"));
Type* slice_type = Type::make_array_type(this->element_type_, NULL);
vals->push_back(Expression::make_type_descriptor(slice_type, bloc));
++p;
go_assert(p->is_field_name("len"));
vals->push_back(Expression::make_cast(p->type(), this->length_, bloc));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(atdt, vals, bloc);
}
// Build a type descriptor for a slice type.
Expression*
Array_type::slice_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* stdt = Array_type::make_slice_type_descriptor_type();
const Struct_field_list* fields = stdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(2);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_SLICE,
name, NULL, true));
++p;
go_assert(p->is_field_name("elem"));
vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(stdt, vals, bloc);
}
// Reflection string.
void
Array_type::do_reflection(Gogo* gogo, std::string* ret) const
{
ret->push_back('[');
if (this->length_ != NULL)
{
Numeric_constant nc;
if (!this->length_->numeric_constant_value(&nc))
{
go_assert(saw_errors());
return;
}
mpz_t val;
if (!nc.to_int(&val))
{
go_assert(saw_errors());
return;
}
char* s = mpz_get_str(NULL, 10, val);
ret->append(s);
free(s);
mpz_clear(val);
}
ret->push_back(']');
this->append_reflection(this->element_type_, gogo, ret);
}
// Make an array type.
Array_type*
Type::make_array_type(Type* element_type, Expression* length)
{
return new Array_type(element_type, length);
}
// Class Map_type.
Named_object* Map_type::zero_value;
int64_t Map_type::zero_value_size;
int64_t Map_type::zero_value_align;
// If this map requires the "fat" functions, return the pointer to
// pass as the zero value to those functions. Otherwise, in the
// normal case, return NULL. The map requires the "fat" functions if
// the value size is larger than max_zero_size bytes. max_zero_size
// must match maxZero in libgo/go/runtime/hashmap.go.
Expression*
Map_type::fat_zero_value(Gogo* gogo)
{
int64_t valsize;
if (!this->val_type_->backend_type_size(gogo, &valsize))
{
go_assert(saw_errors());
return NULL;
}
if (valsize <= Map_type::max_zero_size)
return NULL;
if (Map_type::zero_value_size < valsize)
Map_type::zero_value_size = valsize;
int64_t valalign;
if (!this->val_type_->backend_type_align(gogo, &valalign))
{
go_assert(saw_errors());
return NULL;
}
if (Map_type::zero_value_align < valalign)
Map_type::zero_value_align = valalign;
Location bloc = Linemap::predeclared_location();
if (Map_type::zero_value == NULL)
{
// The final type will be set in backend_zero_value.
Type* uint8_type = Type::lookup_integer_type("uint8");
Expression* size = Expression::make_integer_ul(0, NULL, bloc);
Array_type* array_type = Type::make_array_type(uint8_type, size);
array_type->set_is_array_incomparable();
Variable* var = new Variable(array_type, NULL, true, false, false, bloc);
std::string name = gogo->map_zero_value_name();
Map_type::zero_value = Named_object::make_variable(name, NULL, var);
}
Expression* z = Expression::make_var_reference(Map_type::zero_value, bloc);
z = Expression::make_unary(OPERATOR_AND, z, bloc);
Type* unsafe_ptr_type = Type::make_pointer_type(Type::make_void_type());
z = Expression::make_cast(unsafe_ptr_type, z, bloc);
return z;
}
// Return whether VAR is the map zero value.
bool
Map_type::is_zero_value(Variable* var)
{
return (Map_type::zero_value != NULL
&& Map_type::zero_value->var_value() == var);
}
// Return the backend representation for the zero value.
Bvariable*
Map_type::backend_zero_value(Gogo* gogo)
{
Location bloc = Linemap::predeclared_location();
go_assert(Map_type::zero_value != NULL);
Type* uint8_type = Type::lookup_integer_type("uint8");
Btype* buint8_type = uint8_type->get_backend(gogo);
Type* int_type = Type::lookup_integer_type("int");
Expression* e = Expression::make_integer_int64(Map_type::zero_value_size,
int_type, bloc);
Translate_context context(gogo, NULL, NULL, NULL);
Bexpression* blength = e->get_backend(&context);
Btype* barray_type = gogo->backend()->array_type(buint8_type, blength);
std::string zname = Map_type::zero_value->name();
std::string asm_name(go_selectively_encode_id(zname));
Bvariable* zvar =
gogo->backend()->implicit_variable(zname, asm_name,
barray_type, false, false, true,
Map_type::zero_value_align);
gogo->backend()->implicit_variable_set_init(zvar, zname, barray_type,
false, false, true, NULL);
return zvar;
}
// Traversal.
int
Map_type::do_traverse(Traverse* traverse)
{
if (Type::traverse(this->key_type_, traverse) == TRAVERSE_EXIT
|| Type::traverse(this->val_type_, traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
return TRAVERSE_CONTINUE;
}
// Check that the map type is OK.
bool
Map_type::do_verify()
{
// The runtime support uses "map[void]void".
if (!this->key_type_->is_comparable() && !this->key_type_->is_void_type())
go_error_at(this->location_, "invalid map key type");
if (!this->key_type_->in_heap())
go_error_at(this->location_, "go:notinheap map key not allowed");
if (!this->val_type_->in_heap())
go_error_at(this->location_, "go:notinheap map value not allowed");
return true;
}
// Whether two map types are identical.
bool
Map_type::is_identical(const Map_type* t, Cmp_tags cmp_tags,
bool errors_are_identical) const
{
return (Type::are_identical_cmp_tags(this->key_type(), t->key_type(),
cmp_tags, errors_are_identical, NULL)
&& Type::are_identical_cmp_tags(this->val_type(), t->val_type(),
cmp_tags, errors_are_identical,
NULL));
}
// Hash code.
unsigned int
Map_type::do_hash_for_method(Gogo* gogo) const
{
return (this->key_type_->hash_for_method(gogo)
+ this->val_type_->hash_for_method(gogo)
+ 2);
}
// Get the backend representation for a map type. A map type is
// represented as a pointer to a struct. The struct is hmap in
// runtime/hashmap.go.
Btype*
Map_type::do_get_backend(Gogo* gogo)
{
static Btype* backend_map_type;
if (backend_map_type == NULL)
{
std::vector<Backend::Btyped_identifier> bfields(9);
Location bloc = Linemap::predeclared_location();
Type* int_type = Type::lookup_integer_type("int");
bfields[0].name = "count";
bfields[0].btype = int_type->get_backend(gogo);
bfields[0].location = bloc;
Type* uint8_type = Type::lookup_integer_type("uint8");
bfields[1].name = "flags";
bfields[1].btype = uint8_type->get_backend(gogo);
bfields[1].location = bloc;
bfields[2].name = "B";
bfields[2].btype = bfields[1].btype;
bfields[2].location = bloc;
Type* uint16_type = Type::lookup_integer_type("uint16");
bfields[3].name = "noverflow";
bfields[3].btype = uint16_type->get_backend(gogo);
bfields[3].location = bloc;
Type* uint32_type = Type::lookup_integer_type("uint32");
bfields[4].name = "hash0";
bfields[4].btype = uint32_type->get_backend(gogo);
bfields[4].location = bloc;
Btype* bvt = gogo->backend()->void_type();
Btype* bpvt = gogo->backend()->pointer_type(bvt);
bfields[5].name = "buckets";
bfields[5].btype = bpvt;
bfields[5].location = bloc;
bfields[6].name = "oldbuckets";
bfields[6].btype = bpvt;
bfields[6].location = bloc;
Type* uintptr_type = Type::lookup_integer_type("uintptr");
bfields[7].name = "nevacuate";
bfields[7].btype = uintptr_type->get_backend(gogo);
bfields[7].location = bloc;
bfields[8].name = "extra";
bfields[8].btype = bpvt;
bfields[8].location = bloc;
Btype *bt = gogo->backend()->struct_type(bfields);
bt = gogo->backend()->named_type("runtime.hmap", bt, bloc);
backend_map_type = gogo->backend()->pointer_type(bt);
}
return backend_map_type;
}
// The type of a map type descriptor.
Type*
Map_type::make_map_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* uint16_type = Type::lookup_integer_type("uint16");
Type* bool_type = Type::lookup_bool_type();
Struct_type* sf =
Type::make_builtin_struct_type(12,
"", tdt,
"key", ptdt,
"elem", ptdt,
"bucket", ptdt,
"hmap", ptdt,
"keysize", uint8_type,
"indirectkey", bool_type,
"valuesize", uint8_type,
"indirectvalue", bool_type,
"bucketsize", uint16_type,
"reflexivekey", bool_type,
"needkeyupdate", bool_type);
ret = Type::make_builtin_named_type("MapType", sf);
}
return ret;
}
// Build a type descriptor for a map type.
Expression*
Map_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* mtdt = Map_type::make_map_type_descriptor_type();
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* uint16_type = Type::lookup_integer_type("uint16");
int64_t keysize;
if (!this->key_type_->backend_type_size(gogo, &keysize))
{
go_error_at(this->location_, "error determining map key type size");
return Expression::make_error(this->location_);
}
int64_t valsize;
if (!this->val_type_->backend_type_size(gogo, &valsize))
{
go_error_at(this->location_, "error determining map value type size");
return Expression::make_error(this->location_);
}
int64_t ptrsize;
if (!Type::make_pointer_type(uint8_type)->backend_type_size(gogo, &ptrsize))
{
go_assert(saw_errors());
return Expression::make_error(this->location_);
}
Type* bucket_type = this->bucket_type(gogo, keysize, valsize);
if (bucket_type == NULL)
{
go_assert(saw_errors());
return Expression::make_error(this->location_);
}
int64_t bucketsize;
if (!bucket_type->backend_type_size(gogo, &bucketsize))
{
go_assert(saw_errors());
return Expression::make_error(this->location_);
}
const Struct_field_list* fields = mtdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(12);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_MAP,
name, NULL, true));
++p;
go_assert(p->is_field_name("key"));
vals->push_back(Expression::make_type_descriptor(this->key_type_, bloc));
++p;
go_assert(p->is_field_name("elem"));
vals->push_back(Expression::make_type_descriptor(this->val_type_, bloc));
++p;
go_assert(p->is_field_name("bucket"));
vals->push_back(Expression::make_type_descriptor(bucket_type, bloc));
++p;
go_assert(p->is_field_name("hmap"));
Type* hmap_type = this->hmap_type(bucket_type);
vals->push_back(Expression::make_type_descriptor(hmap_type, bloc));
++p;
go_assert(p->is_field_name("keysize"));
if (keysize > Map_type::max_key_size)
vals->push_back(Expression::make_integer_int64(ptrsize, uint8_type, bloc));
else
vals->push_back(Expression::make_integer_int64(keysize, uint8_type, bloc));
++p;
go_assert(p->is_field_name("indirectkey"));
vals->push_back(Expression::make_boolean(keysize > Map_type::max_key_size,
bloc));
++p;
go_assert(p->is_field_name("valuesize"));
if (valsize > Map_type::max_val_size)
vals->push_back(Expression::make_integer_int64(ptrsize, uint8_type, bloc));
else
vals->push_back(Expression::make_integer_int64(valsize, uint8_type, bloc));
++p;
go_assert(p->is_field_name("indirectvalue"));
vals->push_back(Expression::make_boolean(valsize > Map_type::max_val_size,
bloc));
++p;
go_assert(p->is_field_name("bucketsize"));
vals->push_back(Expression::make_integer_int64(bucketsize, uint16_type,
bloc));
++p;
go_assert(p->is_field_name("reflexivekey"));
vals->push_back(Expression::make_boolean(this->key_type_->is_reflexive(),
bloc));
++p;
go_assert(p->is_field_name("needkeyupdate"));
vals->push_back(Expression::make_boolean(this->key_type_->needs_key_update(),
bloc));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(mtdt, vals, bloc);
}
// Return the bucket type to use for a map type. This must correspond
// to libgo/go/runtime/hashmap.go.
Type*
Map_type::bucket_type(Gogo* gogo, int64_t keysize, int64_t valsize)
{
if (this->bucket_type_ != NULL)
return this->bucket_type_;
Type* key_type = this->key_type_;
if (keysize > Map_type::max_key_size)
key_type = Type::make_pointer_type(key_type);
Type* val_type = this->val_type_;
if (valsize > Map_type::max_val_size)
val_type = Type::make_pointer_type(val_type);
Expression* bucket_size = Expression::make_integer_ul(Map_type::bucket_size,
NULL, this->location_);
Type* uint8_type = Type::lookup_integer_type("uint8");
Array_type* topbits_type = Type::make_array_type(uint8_type, bucket_size);
topbits_type->set_is_array_incomparable();
Array_type* keys_type = Type::make_array_type(key_type, bucket_size);
keys_type->set_is_array_incomparable();
Array_type* values_type = Type::make_array_type(val_type, bucket_size);
values_type->set_is_array_incomparable();
// If keys and values have no pointers, the map implementation can
// keep a list of overflow pointers on the side so that buckets can
// be marked as having no pointers. Arrange for the bucket to have
// no pointers by changing the type of the overflow field to uintptr
// in this case. See comment on the hmap.overflow field in
// libgo/go/runtime/hashmap.go.
Type* overflow_type;
if (!key_type->has_pointer() && !val_type->has_pointer())
overflow_type = Type::lookup_integer_type("uintptr");
else
{
// This should really be a pointer to the bucket type itself,
// but that would require us to construct a Named_type for it to
// give it a way to refer to itself. Since nothing really cares
// (except perhaps for someone using a debugger) just use an
// unsafe pointer.
overflow_type = Type::make_pointer_type(Type::make_void_type());
}
// Make sure the overflow pointer is the last memory in the struct,
// because the runtime assumes it can use size-ptrSize as the offset
// of the overflow pointer. We double-check that property below
// once the offsets and size are computed.
int64_t topbits_field_size, topbits_field_align;
int64_t keys_field_size, keys_field_align;
int64_t values_field_size, values_field_align;
int64_t overflow_field_size, overflow_field_align;
if (!topbits_type->backend_type_size(gogo, &topbits_field_size)
|| !topbits_type->backend_type_field_align(gogo, &topbits_field_align)
|| !keys_type->backend_type_size(gogo, &keys_field_size)
|| !keys_type->backend_type_field_align(gogo, &keys_field_align)
|| !values_type->backend_type_size(gogo, &values_field_size)
|| !values_type->backend_type_field_align(gogo, &values_field_align)
|| !overflow_type->backend_type_size(gogo, &overflow_field_size)
|| !overflow_type->backend_type_field_align(gogo, &overflow_field_align))
{
go_assert(saw_errors());
return NULL;
}
Struct_type* ret;
int64_t max_align = std::max(std::max(topbits_field_align, keys_field_align),
values_field_align);
if (max_align <= overflow_field_align)
ret = make_builtin_struct_type(4,
"topbits", topbits_type,
"keys", keys_type,
"values", values_type,
"overflow", overflow_type);
else
{
size_t off = topbits_field_size;
off = ((off + keys_field_align - 1)
&~ static_cast<size_t>(keys_field_align - 1));
off += keys_field_size;
off = ((off + values_field_align - 1)
&~ static_cast<size_t>(values_field_align - 1));
off += values_field_size;
int64_t padded_overflow_field_size =
((overflow_field_size + max_align - 1)
&~ static_cast<size_t>(max_align - 1));
size_t ovoff = off;
ovoff = ((ovoff + max_align - 1)
&~ static_cast<size_t>(max_align - 1));
size_t pad = (ovoff - off
+ padded_overflow_field_size - overflow_field_size);
Expression* pad_expr = Expression::make_integer_ul(pad, NULL,
this->location_);
Array_type* pad_type = Type::make_array_type(uint8_type, pad_expr);
pad_type->set_is_array_incomparable();
ret = make_builtin_struct_type(5,
"topbits", topbits_type,
"keys", keys_type,
"values", values_type,
"pad", pad_type,
"overflow", overflow_type);
}
// Verify that the overflow field is just before the end of the
// bucket type.
Btype* btype = ret->get_backend(gogo);
int64_t offset = gogo->backend()->type_field_offset(btype,
ret->field_count() - 1);
int64_t size;
if (!ret->backend_type_size(gogo, &size))
{
go_assert(saw_errors());
return NULL;
}
int64_t ptr_size;
if (!Type::make_pointer_type(uint8_type)->backend_type_size(gogo, &ptr_size))
{
go_assert(saw_errors());
return NULL;
}
go_assert(offset + ptr_size == size);
ret->set_is_struct_incomparable();
this->bucket_type_ = ret;
return ret;
}
// Return the hashmap type for a map type.
Type*
Map_type::hmap_type(Type* bucket_type)
{
if (this->hmap_type_ != NULL)
return this->hmap_type_;
Type* int_type = Type::lookup_integer_type("int");
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* uint16_type = Type::lookup_integer_type("uint16");
Type* uint32_type = Type::lookup_integer_type("uint32");
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* void_ptr_type = Type::make_pointer_type(Type::make_void_type());
Type* ptr_bucket_type = Type::make_pointer_type(bucket_type);
Struct_type* ret = make_builtin_struct_type(9,
"count", int_type,
"flags", uint8_type,
"B", uint8_type,
"noverflow", uint16_type,
"hash0", uint32_type,
"buckets", ptr_bucket_type,
"oldbuckets", ptr_bucket_type,
"nevacuate", uintptr_type,
"extra", void_ptr_type);
ret->set_is_struct_incomparable();
this->hmap_type_ = ret;
return ret;
}
// Return the iterator type for a map type. This is the type of the
// value used when doing a range over a map.
Type*
Map_type::hiter_type(Gogo* gogo)
{
if (this->hiter_type_ != NULL)
return this->hiter_type_;
int64_t keysize, valsize;
if (!this->key_type_->backend_type_size(gogo, &keysize)
|| !this->val_type_->backend_type_size(gogo, &valsize))
{
go_assert(saw_errors());
return NULL;
}
Type* key_ptr_type = Type::make_pointer_type(this->key_type_);
Type* val_ptr_type = Type::make_pointer_type(this->val_type_);
Type* uint8_type = Type::lookup_integer_type("uint8");
Type* uint8_ptr_type = Type::make_pointer_type(uint8_type);
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* bucket_type = this->bucket_type(gogo, keysize, valsize);
Type* bucket_ptr_type = Type::make_pointer_type(bucket_type);
Type* hmap_type = this->hmap_type(bucket_type);
Type* hmap_ptr_type = Type::make_pointer_type(hmap_type);
Type* void_ptr_type = Type::make_pointer_type(Type::make_void_type());
Type* bool_type = Type::lookup_bool_type();
Struct_type* ret = make_builtin_struct_type(15,
"key", key_ptr_type,
"val", val_ptr_type,
"t", uint8_ptr_type,
"h", hmap_ptr_type,
"buckets", bucket_ptr_type,
"bptr", bucket_ptr_type,
"overflow", void_ptr_type,
"oldoverflow", void_ptr_type,
"startBucket", uintptr_type,
"offset", uint8_type,
"wrapped", bool_type,
"B", uint8_type,
"i", uint8_type,
"bucket", uintptr_type,
"checkBucket", uintptr_type);
ret->set_is_struct_incomparable();
this->hiter_type_ = ret;
return ret;
}
// Reflection string for a map.
void
Map_type::do_reflection(Gogo* gogo, std::string* ret) const
{
ret->append("map[");
this->append_reflection(this->key_type_, gogo, ret);
ret->append("]");
this->append_reflection(this->val_type_, gogo, ret);
}
// Export a map type.
void
Map_type::do_export(Export* exp) const
{
exp->write_c_string("map [");
exp->write_type(this->key_type_);
exp->write_c_string("] ");
exp->write_type(this->val_type_);
}
// Import a map type.
Map_type*
Map_type::do_import(Import* imp)
{
imp->require_c_string("map [");
Type* key_type = imp->read_type();
imp->require_c_string("] ");
Type* val_type = imp->read_type();
return Type::make_map_type(key_type, val_type, imp->location());
}
// Make a map type.
Map_type*
Type::make_map_type(Type* key_type, Type* val_type, Location location)
{
return new Map_type(key_type, val_type, location);
}
// Class Channel_type.
// Verify.
bool
Channel_type::do_verify()
{
// We have no location for this error, but this is not something the
// ordinary user will see.
if (!this->element_type_->in_heap())
go_error_at(Linemap::unknown_location(),
"chan of go:notinheap type not allowed");
return true;
}
// Hash code.
unsigned int
Channel_type::do_hash_for_method(Gogo* gogo) const
{
unsigned int ret = 0;
if (this->may_send_)
ret += 1;
if (this->may_receive_)
ret += 2;
if (this->element_type_ != NULL)
ret += this->element_type_->hash_for_method(gogo) << 2;
return ret << 3;
}
// Whether this type is the same as T.
bool
Channel_type::is_identical(const Channel_type* t, Cmp_tags cmp_tags,
bool errors_are_identical) const
{
if (!Type::are_identical_cmp_tags(this->element_type(), t->element_type(),
cmp_tags, errors_are_identical, NULL))
return false;
return (this->may_send_ == t->may_send_
&& this->may_receive_ == t->may_receive_);
}
// Return the backend representation for a channel type. A channel is a pointer
// to a __go_channel struct. The __go_channel struct is defined in
// libgo/runtime/channel.h.
Btype*
Channel_type::do_get_backend(Gogo* gogo)
{
static Btype* backend_channel_type;
if (backend_channel_type == NULL)
{
std::vector<Backend::Btyped_identifier> bfields;
Btype* bt = gogo->backend()->struct_type(bfields);
bt = gogo->backend()->named_type("__go_channel", bt,
Linemap::predeclared_location());
backend_channel_type = gogo->backend()->pointer_type(bt);
}
return backend_channel_type;
}
// Build a type descriptor for a channel type.
Type*
Channel_type::make_chan_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Struct_type* sf =
Type::make_builtin_struct_type(3,
"", tdt,
"elem", ptdt,
"dir", uintptr_type);
ret = Type::make_builtin_named_type("ChanType", sf);
}
return ret;
}
// Build a type descriptor for a map type.
Expression*
Channel_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* ctdt = Channel_type::make_chan_type_descriptor_type();
const Struct_field_list* fields = ctdt->struct_type()->fields();
Expression_list* vals = new Expression_list();
vals->reserve(3);
Struct_field_list::const_iterator p = fields->begin();
go_assert(p->is_field_name("_type"));
vals->push_back(this->type_descriptor_constructor(gogo,
RUNTIME_TYPE_KIND_CHAN,
name, NULL, true));
++p;
go_assert(p->is_field_name("elem"));
vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc));
++p;
go_assert(p->is_field_name("dir"));
// These bits must match the ones in libgo/runtime/go-type.h.
int val = 0;
if (this->may_receive_)
val |= 1;
if (this->may_send_)
val |= 2;
vals->push_back(Expression::make_integer_ul(val, p->type(), bloc));
++p;
go_assert(p == fields->end());
return Expression::make_struct_composite_literal(ctdt, vals, bloc);
}
// Reflection string.
void
Channel_type::do_reflection(Gogo* gogo, std::string* ret) const
{
if (!this->may_send_)
ret->append("<-");
ret->append("chan");
if (!this->may_receive_)
ret->append("<-");
ret->push_back(' ');
this->append_reflection(this->element_type_, gogo, ret);
}
// Export.
void
Channel_type::do_export(Export* exp) const
{
exp->write_c_string("chan ");
if (this->may_send_ && !this->may_receive_)
exp->write_c_string("-< ");
else if (this->may_receive_ && !this->may_send_)
exp->write_c_string("<- ");
exp->write_type(this->element_type_);
}
// Import.
Channel_type*
Channel_type::do_import(Import* imp)
{
imp->require_c_string("chan ");
bool may_send;
bool may_receive;
if (imp->match_c_string("-< "))
{
imp->advance(3);
may_send = true;
may_receive = false;
}
else if (imp->match_c_string("<- "))
{
imp->advance(3);
may_receive = true;
may_send = false;
}
else
{
may_send = true;
may_receive = true;
}
Type* element_type = imp->read_type();
return Type::make_channel_type(may_send, may_receive, element_type);
}
// Return the type to manage a select statement with ncases case
// statements. A value of this type is allocated on the stack. This
// must match the type hselect in libgo/go/runtime/select.go.
Type*
Channel_type::select_type(int ncases)
{
Type* unsafe_pointer_type = Type::make_pointer_type(Type::make_void_type());
Type* uint16_type = Type::lookup_integer_type("uint16");
static Struct_type* scase_type;
if (scase_type == NULL)
{
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* uint64_type = Type::lookup_integer_type("uint64");
scase_type =
Type::make_builtin_struct_type(7,
"elem", unsafe_pointer_type,
"chan", unsafe_pointer_type,
"pc", uintptr_type,
"kind", uint16_type,
"index", uint16_type,
"receivedp", unsafe_pointer_type,
"releasetime", uint64_type);
scase_type->set_is_struct_incomparable();
}
Expression* ncases_expr =
Expression::make_integer_ul(ncases, NULL, Linemap::predeclared_location());
Array_type* scases = Type::make_array_type(scase_type, ncases_expr);
scases->set_is_array_incomparable();
Array_type* order = Type::make_array_type(uint16_type, ncases_expr);
order->set_is_array_incomparable();
Struct_type* ret =
Type::make_builtin_struct_type(7,
"tcase", uint16_type,
"ncase", uint16_type,
"pollorder", unsafe_pointer_type,
"lockorder", unsafe_pointer_type,
"scase", scases,
"lockorderarr", order,
"pollorderarr", order);
ret->set_is_struct_incomparable();
return ret;
}
// Make a new channel type.
Channel_type*
Type::make_channel_type(bool send, bool receive, Type* element_type)
{
return new Channel_type(send, receive, element_type);
}
// Class Interface_type.
// Return the list of methods.
const Typed_identifier_list*
Interface_type::methods() const
{
go_assert(this->methods_are_finalized_ || saw_errors());
return this->all_methods_;
}
// Return the number of methods.
size_t
Interface_type::method_count() const
{
go_assert(this->methods_are_finalized_ || saw_errors());
return this->all_methods_ == NULL ? 0 : this->all_methods_->size();
}
// Traversal.
int
Interface_type::do_traverse(Traverse* traverse)
{
Typed_identifier_list* methods = (this->methods_are_finalized_
? this->all_methods_
: this->parse_methods_);
if (methods == NULL)
return TRAVERSE_CONTINUE;
return methods->traverse(traverse);
}
// Finalize the methods. This handles interface inheritance.
void
Interface_type::finalize_methods()
{
if (this->methods_are_finalized_)
return;
this->methods_are_finalized_ = true;
if (this->parse_methods_ == NULL)
return;
this->all_methods_ = new Typed_identifier_list();
this->all_methods_->reserve(this->parse_methods_->size());
Typed_identifier_list inherit;
for (Typed_identifier_list::const_iterator pm =
this->parse_methods_->begin();
pm != this->parse_methods_->end();
++pm)
{
const Typed_identifier* p = &*pm;
if (p->name().empty())
inherit.push_back(*p);
else if (this->find_method(p->name()) == NULL)
this->all_methods_->push_back(*p);
else
go_error_at(p->location(), "duplicate method %qs",
Gogo::message_name(p->name()).c_str());
}
std::vector<Named_type*> seen;
seen.reserve(inherit.size());
bool issued_recursive_error = false;
while (!inherit.empty())
{
Type* t = inherit.back().type();
Location tl = inherit.back().location();
inherit.pop_back();
Interface_type* it = t->interface_type();
if (it == NULL)
{
if (!t->is_error())
go_error_at(tl, "interface contains embedded non-interface");
continue;
}
if (it == this)
{
if (!issued_recursive_error)
{
go_error_at(tl, "invalid recursive interface");
issued_recursive_error = true;
}
continue;
}
Named_type* nt = t->named_type();
if (nt != NULL && it->parse_methods_ != NULL)
{
std::vector<Named_type*>::const_iterator q;
for (q = seen.begin(); q != seen.end(); ++q)
{
if (*q == nt)
{
go_error_at(tl, "inherited interface loop");
break;
}
}
if (q != seen.end())
continue;
seen.push_back(nt);
}
const Typed_identifier_list* imethods = it->parse_methods_;
if (imethods == NULL)
continue;
for (Typed_identifier_list::const_iterator q = imethods->begin();
q != imethods->end();
++q)
{
if (q->name().empty())
inherit.push_back(*q);
else if (this->find_method(q->name()) == NULL)
this->all_methods_->push_back(Typed_identifier(q->name(),
q->type(), tl));
else
go_error_at(tl, "inherited method %qs is ambiguous",
Gogo::message_name(q->name()).c_str());
}
}
if (!this->all_methods_->empty())
this->all_methods_->sort_by_name();
else
{
delete this->all_methods_;
this->all_methods_ = NULL;
}
}
// Return the method NAME, or NULL.
const Typed_identifier*
Interface_type::find_method(const std::string& name) const
{
go_assert(this->methods_are_finalized_);
if (this->all_methods_ == NULL)
return NULL;
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p)
if (p->name() == name)
return &*p;
return NULL;
}
// Return the method index.
size_t
Interface_type::method_index(const std::string& name) const
{
go_assert(this->methods_are_finalized_ && this->all_methods_ != NULL);
size_t ret = 0;
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p, ++ret)
if (p->name() == name)
return ret;
go_unreachable();
}
// Return whether NAME is an unexported method, for better error
// reporting.
bool
Interface_type::is_unexported_method(Gogo* gogo, const std::string& name) const
{
go_assert(this->methods_are_finalized_);
if (this->all_methods_ == NULL)
return false;
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p)
{
const std::string& method_name(p->name());
if (Gogo::is_hidden_name(method_name)
&& name == Gogo::unpack_hidden_name(method_name)
&& gogo->pack_hidden_name(name, false) != method_name)
return true;
}
return false;
}
// Whether this type is identical with T.
bool
Interface_type::is_identical(const Interface_type* t, Cmp_tags cmp_tags,
bool errors_are_identical) const
{
// If methods have not been finalized, then we are asking whether
// func redeclarations are the same. This is an error, so for
// simplicity we say they are never the same.
if (!this->methods_are_finalized_ || !t->methods_are_finalized_)
return false;
// We require the same methods with the same types. The methods
// have already been sorted.
if (this->all_methods_ == NULL || t->all_methods_ == NULL)
return this->all_methods_ == t->all_methods_;
if (this->assume_identical(this, t) || t->assume_identical(t, this))
return true;
Assume_identical* hold_ai = this->assume_identical_;
Assume_identical ai;
ai.t1 = this;
ai.t2 = t;
ai.next = hold_ai;
this->assume_identical_ = &ai;
Typed_identifier_list::const_iterator p1 = this->all_methods_->begin();
Typed_identifier_list::const_iterator p2;
for (p2 = t->all_methods_->begin(); p2 != t->all_methods_->end(); ++p1, ++p2)
{
if (p1 == this->all_methods_->end())
break;
if (p1->name() != p2->name()
|| !Type::are_identical_cmp_tags(p1->type(), p2->type(), cmp_tags,
errors_are_identical, NULL))
break;
}
this->assume_identical_ = hold_ai;
return p1 == this->all_methods_->end() && p2 == t->all_methods_->end();
}
// Return true if T1 and T2 are assumed to be identical during a type
// comparison.
bool
Interface_type::assume_identical(const Interface_type* t1,
const Interface_type* t2) const
{
for (Assume_identical* p = this->assume_identical_;
p != NULL;
p = p->next)
if ((p->t1 == t1 && p->t2 == t2) || (p->t1 == t2 && p->t2 == t1))
return true;
return false;
}
// Whether we can assign the interface type T to this type. The types
// are known to not be identical. An interface assignment is only
// permitted if T is known to implement all methods in THIS.
// Otherwise a type guard is required.
bool
Interface_type::is_compatible_for_assign(const Interface_type* t,
std::string* reason) const
{
go_assert(this->methods_are_finalized_ && t->methods_are_finalized_);
if (this->all_methods_ == NULL)
return true;
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p)
{
const Typed_identifier* m = t->find_method(p->name());
if (m == NULL)
{
if (reason != NULL)
{
char buf[200];
snprintf(buf, sizeof buf,
_("need explicit conversion; missing method %s%s%s"),
go_open_quote(), Gogo::message_name(p->name()).c_str(),
go_close_quote());
reason->assign(buf);
}
return false;
}
std::string subreason;
if (!Type::are_identical(p->type(), m->type(), true, &subreason))
{
if (reason != NULL)
{
std::string n = Gogo::message_name(p->name());
size_t len = 100 + n.length() + subreason.length();
char* buf = new char[len];
if (subreason.empty())
snprintf(buf, len, _("incompatible type for method %s%s%s"),
go_open_quote(), n.c_str(), go_close_quote());
else
snprintf(buf, len,
_("incompatible type for method %s%s%s (%s)"),
go_open_quote(), n.c_str(), go_close_quote(),
subreason.c_str());
reason->assign(buf);
delete[] buf;
}
return false;
}
}
return true;
}
// Hash code.
unsigned int
Interface_type::do_hash_for_method(Gogo*) const
{
go_assert(this->methods_are_finalized_);
unsigned int ret = 0;
if (this->all_methods_ != NULL)
{
for (Typed_identifier_list::const_iterator p =
this->all_methods_->begin();
p != this->all_methods_->end();
++p)
{
ret = Type::hash_string(p->name(), ret);
// We don't use the method type in the hash, to avoid
// infinite recursion if an interface method uses a type
// which is an interface which inherits from the interface
// itself.
// type T interface { F() interface {T}}
ret <<= 1;
}
}
return ret;
}
// Return true if T implements the interface. If it does not, and
// REASON is not NULL, set *REASON to a useful error message.
bool
Interface_type::implements_interface(const Type* t, std::string* reason) const
{
go_assert(this->methods_are_finalized_);
if (this->all_methods_ == NULL)
return true;
bool is_pointer = false;
const Named_type* nt = t->named_type();
const Struct_type* st = t->struct_type();
// If we start with a named type, we don't dereference it to find
// methods.
if (nt == NULL)
{
const Type* pt = t->points_to();
if (pt != NULL)
{
// If T is a pointer to a named type, then we need to look at
// the type to which it points.
is_pointer = true;
nt = pt->named_type();
st = pt->struct_type();
}
}
// If we have a named type, get the methods from it rather than from
// any struct type.
if (nt != NULL)
st = NULL;
// Only named and struct types have methods.
if (nt == NULL && st == NULL)
{
if (reason != NULL)
{
if (t->points_to() != NULL
&& t->points_to()->interface_type() != NULL)
reason->assign(_("pointer to interface type has no methods"));
else
reason->assign(_("type has no methods"));
}
return false;
}
if (nt != NULL ? !nt->has_any_methods() : !st->has_any_methods())
{
if (reason != NULL)
{
if (t->points_to() != NULL
&& t->points_to()->interface_type() != NULL)
reason->assign(_("pointer to interface type has no methods"));
else
reason->assign(_("type has no methods"));
}
return false;
}
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p)
{
bool is_ambiguous = false;
Method* m = (nt != NULL
? nt->method_function(p->name(), &is_ambiguous)
: st->method_function(p->name(), &is_ambiguous));
if (m == NULL)
{
if (reason != NULL)
{
std::string n = Gogo::message_name(p->name());
size_t len = n.length() + 100;
char* buf = new char[len];
if (is_ambiguous)
snprintf(buf, len, _("ambiguous method %s%s%s"),
go_open_quote(), n.c_str(), go_close_quote());
else
snprintf(buf, len, _("missing method %s%s%s"),
go_open_quote(), n.c_str(), go_close_quote());
reason->assign(buf);
delete[] buf;
}
return false;
}
Function_type *p_fn_type = p->type()->function_type();
Function_type* m_fn_type = m->type()->function_type();
go_assert(p_fn_type != NULL && m_fn_type != NULL);
std::string subreason;
if (!p_fn_type->is_identical(m_fn_type, true, COMPARE_TAGS, true,
&subreason))
{
if (reason != NULL)
{
std::string n = Gogo::message_name(p->name());
size_t len = 100 + n.length() + subreason.length();
char* buf = new char[len];
if (subreason.empty())
snprintf(buf, len, _("incompatible type for method %s%s%s"),
go_open_quote(), n.c_str(), go_close_quote());
else
snprintf(buf, len,
_("incompatible type for method %s%s%s (%s)"),
go_open_quote(), n.c_str(), go_close_quote(),
subreason.c_str());
reason->assign(buf);
delete[] buf;
}
return false;
}
if (!is_pointer && !m->is_value_method())
{
if (reason != NULL)
{
std::string n = Gogo::message_name(p->name());
size_t len = 100 + n.length();
char* buf = new char[len];
snprintf(buf, len,
_("method %s%s%s requires a pointer receiver"),
go_open_quote(), n.c_str(), go_close_quote());
reason->assign(buf);
delete[] buf;
}
return false;
}
// If the magic //go:nointerface comment was used, the method
// may not be used to implement interfaces.
if (m->nointerface())
{
if (reason != NULL)
{
std::string n = Gogo::message_name(p->name());
size_t len = 100 + n.length();
char* buf = new char[len];
snprintf(buf, len,
_("method %s%s%s is marked go:nointerface"),
go_open_quote(), n.c_str(), go_close_quote());
reason->assign(buf);
delete[] buf;
}
return false;
}
}
return true;
}
// Return the backend representation of the empty interface type. We
// use the same struct for all empty interfaces.
Btype*
Interface_type::get_backend_empty_interface_type(Gogo* gogo)
{
static Btype* empty_interface_type;
if (empty_interface_type == NULL)
{
std::vector<Backend::Btyped_identifier> bfields(2);
Location bloc = Linemap::predeclared_location();
Type* pdt = Type::make_type_descriptor_ptr_type();
bfields[0].name = "__type_descriptor";
bfields[0].btype = pdt->get_backend(gogo);
bfields[0].location = bloc;
Type* vt = Type::make_pointer_type(Type::make_void_type());
bfields[1].name = "__object";
bfields[1].btype = vt->get_backend(gogo);
bfields[1].location = bloc;
empty_interface_type = gogo->backend()->struct_type(bfields);
}
return empty_interface_type;
}
Interface_type::Bmethods_map Interface_type::bmethods_map;
// Return a pointer to the backend representation of the method table.
Btype*
Interface_type::get_backend_methods(Gogo* gogo)
{
if (this->bmethods_ != NULL && !this->bmethods_is_placeholder_)
return this->bmethods_;
std::pair<Interface_type*, Bmethods_map_entry> val;
val.first = this;
val.second.btype = NULL;
val.second.is_placeholder = false;
std::pair<Bmethods_map::iterator, bool> ins =
Interface_type::bmethods_map.insert(val);
if (!ins.second
&& ins.first->second.btype != NULL
&& !ins.first->second.is_placeholder)
{
this->bmethods_ = ins.first->second.btype;
this->bmethods_is_placeholder_ = false;
return this->bmethods_;
}
Location loc = this->location();
std::vector<Backend::Btyped_identifier>
mfields(this->all_methods_->size() + 1);
Type* pdt = Type::make_type_descriptor_ptr_type();
mfields[0].name = "__type_descriptor";
mfields[0].btype = pdt->get_backend(gogo);
mfields[0].location = loc;
std::string last_name = "";
size_t i = 1;
for (Typed_identifier_list::const_iterator p = this->all_methods_->begin();
p != this->all_methods_->end();
++p, ++i)
{
// The type of the method in Go only includes the parameters.
// The actual method also has a receiver, which is always a
// pointer. We need to add that pointer type here in order to
// generate the correct type for the backend.
Function_type* ft = p->type()->function_type();
go_assert(ft->receiver() == NULL);
const Typed_identifier_list* params = ft->parameters();
Typed_identifier_list* mparams = new Typed_identifier_list();
if (params != NULL)
mparams->reserve(params->size() + 1);
Type* vt = Type::make_pointer_type(Type::make_void_type());
mparams->push_back(Typed_identifier("", vt, ft->location()));
if (params != NULL)
{
for (Typed_identifier_list::const_iterator pp = params->begin();
pp != params->end();
++pp)
mparams->push_back(*pp);
}
Typed_identifier_list* mresults = (ft->results() == NULL
? NULL
: ft->results()->copy());
Function_type* mft = Type::make_function_type(NULL, mparams, mresults,
ft->location());
mfields[i].name = Gogo::unpack_hidden_name(p->name());
mfields[i].btype = mft->get_backend_fntype(gogo);
mfields[i].location = loc;
// Sanity check: the names should be sorted.
go_assert(Gogo::unpack_hidden_name(p->name())
> Gogo::unpack_hidden_name(last_name));
last_name = p->name();
}
Btype* st = gogo->backend()->struct_type(mfields);
Btype* ret = gogo->backend()->pointer_type(st);
if (ins.first->second.btype != NULL
&& ins.first->second.is_placeholder)
gogo->backend()->set_placeholder_pointer_type(ins.first->second.btype,
ret);
this->bmethods_ = ret;
ins.first->second.btype = ret;
this->bmethods_is_placeholder_ = false;
ins.first->second.is_placeholder = false;
return ret;
}
// Return a placeholder for the pointer to the backend methods table.
Btype*
Interface_type::get_backend_methods_placeholder(Gogo* gogo)
{
if (this->bmethods_ == NULL)
{
std::pair<Interface_type*, Bmethods_map_entry> val;
val.first = this;
val.second.btype = NULL;
val.second.is_placeholder = false;
std::pair<Bmethods_map::iterator, bool> ins =
Interface_type::bmethods_map.insert(val);
if (!ins.second && ins.first->second.btype != NULL)
{
this->bmethods_ = ins.first->second.btype;
this->bmethods_is_placeholder_ = ins.first->second.is_placeholder;
return this->bmethods_;
}
Location loc = this->location();
Btype* bt = gogo->backend()->placeholder_pointer_type("", loc, false);
this->bmethods_ = bt;
ins.first->second.btype = bt;
this->bmethods_is_placeholder_ = true;
ins.first->second.is_placeholder = true;
}
return this->bmethods_;
}
// Return the fields of a non-empty interface type. This is not
// declared in types.h so that types.h doesn't have to #include
// backend.h.
static void
get_backend_interface_fields(Gogo* gogo, Interface_type* type,
bool use_placeholder,
std::vector<Backend::Btyped_identifier>* bfields)
{
Location loc = type->location();
bfields->resize(2);
(*bfields)[0].name = "__methods";
(*bfields)[0].btype = (use_placeholder
? type->get_backend_methods_placeholder(gogo)
: type->get_backend_methods(gogo));
(*bfields)[0].location = loc;
Type* vt = Type::make_pointer_type(Type::make_void_type());
(*bfields)[1].name = "__object";
(*bfields)[1].btype = vt->get_backend(gogo);
(*bfields)[1].location = Linemap::predeclared_location();
}
// Return the backend representation for an interface type. An interface is a
// pointer to a struct. The struct has three fields. The first field is a
// pointer to the type descriptor for the dynamic type of the object.
// The second field is a pointer to a table of methods for the
// interface to be used with the object. The third field is the value
// of the object itself.
Btype*
Interface_type::do_get_backend(Gogo* gogo)
{
if (this->is_empty())
return Interface_type::get_backend_empty_interface_type(gogo);
else
{
if (this->interface_btype_ != NULL)
return this->interface_btype_;
this->interface_btype_ =
gogo->backend()->placeholder_struct_type("", this->location_);
std::vector<Backend::Btyped_identifier> bfields;
get_backend_interface_fields(gogo, this, false, &bfields);
if (!gogo->backend()->set_placeholder_struct_type(this->interface_btype_,
bfields))
this->interface_btype_ = gogo->backend()->error_type();
return this->interface_btype_;
}
}
// Finish the backend representation of the methods.
void
Interface_type::finish_backend_methods(Gogo* gogo)
{
if (!this->is_empty())
{
const Typed_identifier_list* methods = this->methods();
if (methods != NULL)
{
for (Typed_identifier_list::const_iterator p = methods->begin();
p != methods->end();
++p)
p->type()->get_backend(gogo);
}
// Getting the backend methods now will set the placeholder
// pointer.
this->get_backend_methods(gogo);
}
}
// The type of an interface type descriptor.
Type*
Interface_type::make_interface_type_descriptor_type()
{
static Type* ret;
if (ret == NULL)
{
Type* tdt = Type::make_type_descriptor_type();
Type* ptdt = Type::make_type_descriptor_ptr_type();
Type* string_type = Type::lookup_string_type();
Type* pointer_string_type = Type::make_pointer_type(string_type);
Struct_type* sm =
Type::make_builtin_struct_type(3,
"name", pointer_string_type,
"pkgPath", pointer_string_type,
"typ", ptdt);
Type* nsm = Type::make_builtin_named_type("imethod", sm);
Type* slice_nsm = Type::make_array_type(nsm, NULL);
Struct_type* s = Type::make_builtin_struct_type(2,
"", tdt,
"methods", slice_nsm);
ret = Type::make_builtin_named_type("InterfaceType", s);
}
return ret;
}
// Build a type descriptor for an interface type.
Expression*
Interface_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location bloc = Linemap::predeclared_location();
Type* itdt = Interface_type::make_interface_type_descriptor_type();
const Struct_field_list* ifields = itdt->struct_type()->fields();
Expression_list* ivals = new Expression_list();
ivals->reserve(2);
Struct_field_list::const_iterator pif = ifields->begin();
go_assert(pif->is_field_name("_type"));
const int rt = RUNTIME_TYPE_KIND_INTERFACE;
ivals->push_back(this->type_descriptor_constructor(gogo, rt, name, NULL,
true));
++pif;
go_assert(pif->is_field_name("methods"));
Expression_list* methods = new Expression_list();
if (this->all_methods_ != NULL)
{
Type* elemtype = pif->type()->array_type()->element_type();
methods->reserve(this->all_methods_->size());
for (Typed_identifier_list::const_iterator pm =
this->all_methods_->begin();
pm != this->all_methods_->end();
++pm)
{
const Struct_field_list* mfields = elemtype->struct_type()->fields();
Expression_list* mvals = new Expression_list();
mvals->reserve(3);
Struct_field_list::const_iterator pmf = mfields->begin();
go_assert(pmf->is_field_name("name"));
std::string s = Gogo::unpack_hidden_name(pm->name());
Expression* e = Expression::make_string(s, bloc);
mvals->push_back(Expression::make_unary(OPERATOR_AND, e, bloc));
++pmf;
go_assert(pmf->is_field_name("pkgPath"));
if (!Gogo::is_hidden_name(pm->name()))
mvals->push_back(Expression::make_nil(bloc));
else
{
s = Gogo::hidden_name_pkgpath(pm->name());
e = Expression::make_string(s, bloc);
mvals->push_back(Expression::make_unary(OPERATOR_AND, e, bloc));
}
++pmf;
go_assert(pmf->is_field_name("typ"));
mvals->push_back(Expression::make_type_descriptor(pm->type(), bloc));
++pmf;
go_assert(pmf == mfields->end());
e = Expression::make_struct_composite_literal(elemtype, mvals,
bloc);
methods->push_back(e);
}
}
ivals->push_back(Expression::make_slice_composite_literal(pif->type(),
methods, bloc));
++pif;
go_assert(pif == ifields->end());
return Expression::make_struct_composite_literal(itdt, ivals, bloc);
}
// Reflection string.
void
Interface_type::do_reflection(Gogo* gogo, std::string* ret) const
{
ret->append("interface {");
const Typed_identifier_list* methods = this->parse_methods_;
if (methods != NULL)
{
ret->push_back(' ');
for (Typed_identifier_list::const_iterator p = methods->begin();
p != methods->end();
++p)
{
if (p != methods->begin())
ret->append("; ");
if (p->name().empty())
this->append_reflection(p->type(), gogo, ret);
else
{
if (!Gogo::is_hidden_name(p->name()))
ret->append(p->name());
else if (gogo->pkgpath_from_option())
ret->append(p->name().substr(1));
else
{
// If no -fgo-pkgpath option, backward compatibility
// for how this used to work before -fgo-pkgpath was
// introduced.
std::string pkgpath = Gogo::hidden_name_pkgpath(p->name());
ret->append(pkgpath.substr(pkgpath.find('.') + 1));
ret->push_back('.');
ret->append(Gogo::unpack_hidden_name(p->name()));
}
std::string sub = p->type()->reflection(gogo);
go_assert(sub.compare(0, 4, "func") == 0);
sub = sub.substr(4);
ret->append(sub);
}
}
ret->push_back(' ');
}
ret->append("}");
}
// Export.
void
Interface_type::do_export(Export* exp) const
{
exp->write_c_string("interface { ");
const Typed_identifier_list* methods = this->parse_methods_;
if (methods != NULL)
{
for (Typed_identifier_list::const_iterator pm = methods->begin();
pm != methods->end();
++pm)
{
if (pm->name().empty())
{
exp->write_c_string("? ");
exp->write_type(pm->type());
}
else
{
exp->write_string(pm->name());
exp->write_c_string(" (");
const Function_type* fntype = pm->type()->function_type();
bool first = true;
const Typed_identifier_list* parameters = fntype->parameters();
if (parameters != NULL)
{
bool is_varargs = fntype->is_varargs();
for (Typed_identifier_list::const_iterator pp =
parameters->begin();
pp != parameters->end();
++pp)
{
if (first)
first = false;
else
exp->write_c_string(", ");
exp->write_name(pp->name());
exp->write_c_string(" ");
if (!is_varargs || pp + 1 != parameters->end())
exp->write_type(pp->type());
else
{
exp->write_c_string("...");
Type *pptype = pp->type();
exp->write_type(pptype->array_type()->element_type());
}
}
}
exp->write_c_string(")");
const Typed_identifier_list* results = fntype->results();
if (results != NULL)
{
exp->write_c_string(" ");
if (results->size() == 1 && results->begin()->name().empty())
exp->write_type(results->begin()->type());
else
{
first = true;
exp->write_c_string("(");
for (Typed_identifier_list::const_iterator p =
results->begin();
p != results->end();
++p)
{
if (first)
first = false;
else
exp->write_c_string(", ");
exp->write_name(p->name());
exp->write_c_string(" ");
exp->write_type(p->type());
}
exp->write_c_string(")");
}
}
}
exp->write_c_string("; ");
}
}
exp->write_c_string("}");
}
// Import an interface type.
Interface_type*
Interface_type::do_import(Import* imp)
{
imp->require_c_string("interface { ");
Typed_identifier_list* methods = new Typed_identifier_list;
while (imp->peek_char() != '}')
{
std::string name = imp->read_identifier();
if (name == "?")
{
imp->require_c_string(" ");
Type* t = imp->read_type();
methods->push_back(Typed_identifier("", t, imp->location()));
imp->require_c_string("; ");
continue;
}
imp->require_c_string(" (");
Typed_identifier_list* parameters;
bool is_varargs = false;
if (imp->peek_char() == ')')
parameters = NULL;
else
{
parameters = new Typed_identifier_list;
while (true)
{
std::string name = imp->read_name();
imp->require_c_string(" ");
if (imp->match_c_string("..."))
{
imp->advance(3);
is_varargs = true;
}
Type* ptype = imp->read_type();
if (is_varargs)
ptype = Type::make_array_type(ptype, NULL);
parameters->push_back(Typed_identifier(name, ptype,
imp->location()));
if (imp->peek_char() != ',')
break;
go_assert(!is_varargs);
imp->require_c_string(", ");
}
}
imp->require_c_string(")");
Typed_identifier_list* results;
if (imp->peek_char() != ' ')
results = NULL;
else
{
results = new Typed_identifier_list;
imp->advance(1);
if (imp->peek_char() != '(')
{
Type* rtype = imp->read_type();
results->push_back(Typed_identifier("", rtype, imp->location()));
}
else
{
imp->advance(1);
while (true)
{
std::string name = imp->read_name();
imp->require_c_string(" ");
Type* rtype = imp->read_type();
results->push_back(Typed_identifier(name, rtype,
imp->location()));
if (imp->peek_char() != ',')
break;
imp->require_c_string(", ");
}
imp->require_c_string(")");
}
}
Function_type* fntype = Type::make_function_type(NULL, parameters,
results,
imp->location());
if (is_varargs)
fntype->set_is_varargs();
methods->push_back(Typed_identifier(name, fntype, imp->location()));
imp->require_c_string("; ");
}
imp->require_c_string("}");
if (methods->empty())
{
delete methods;
methods = NULL;
}
Interface_type* ret = Type::make_interface_type(methods, imp->location());
ret->package_ = imp->package();
return ret;
}
// Make an interface type.
Interface_type*
Type::make_interface_type(Typed_identifier_list* methods,
Location location)
{
return new Interface_type(methods, location);
}
// Make an empty interface type.
Interface_type*
Type::make_empty_interface_type(Location location)
{
Interface_type* ret = new Interface_type(NULL, location);
ret->finalize_methods();
return ret;
}
// Class Method.
// Bind a method to an object.
Expression*
Method::bind_method(Expression* expr, Location location) const
{
if (this->stub_ == NULL)
{
// When there is no stub object, the binding is determined by
// the child class.
return this->do_bind_method(expr, location);
}
return Expression::make_bound_method(expr, this, this->stub_, location);
}
// Return the named object associated with a method. This may only be
// called after methods are finalized.
Named_object*
Method::named_object() const
{
if (this->stub_ != NULL)
return this->stub_;
return this->do_named_object();
}
// Class Named_method.
// The type of the method.
Function_type*
Named_method::do_type() const
{
if (this->named_object_->is_function())
return this->named_object_->func_value()->type();
else if (this->named_object_->is_function_declaration())
return this->named_object_->func_declaration_value()->type();
else
go_unreachable();
}
// Return the location of the method receiver.
Location
Named_method::do_receiver_location() const
{
return this->do_type()->receiver()->location();
}
// Bind a method to an object.
Expression*
Named_method::do_bind_method(Expression* expr, Location location) const
{
Named_object* no = this->named_object_;
Bound_method_expression* bme = Expression::make_bound_method(expr, this,
no, location);
// If this is not a local method, and it does not use a stub, then
// the real method expects a different type. We need to cast the
// first argument.
if (this->depth() > 0 && !this->needs_stub_method())
{
Function_type* ftype = this->do_type();
go_assert(ftype->is_method());
Type* frtype = ftype->receiver()->type();
bme->set_first_argument_type(frtype);
}
return bme;
}
// Return whether this method should not participate in interfaces.
bool
Named_method::do_nointerface() const
{
Named_object* no = this->named_object_;
if (no->is_function())
return no->func_value()->nointerface();
else if (no->is_function_declaration())
return no->func_declaration_value()->nointerface();
else
go_unreachable();
}
// Class Interface_method.
// Bind a method to an object.
Expression*
Interface_method::do_bind_method(Expression* expr,
Location location) const
{
return Expression::make_interface_field_reference(expr, this->name_,
location);
}
// Class Methods.
// Insert a new method. Return true if it was inserted, false
// otherwise.
bool
Methods::insert(const std::string& name, Method* m)
{
std::pair<Method_map::iterator, bool> ins =
this->methods_.insert(std::make_pair(name, m));
if (ins.second)
return true;
else
{
Method* old_method = ins.first->second;
if (m->depth() < old_method->depth())
{
delete old_method;
ins.first->second = m;
return true;
}
else
{
if (m->depth() == old_method->depth())
old_method->set_is_ambiguous();
return false;
}
}
}
// Return the number of unambiguous methods.
size_t
Methods::count() const
{
size_t ret = 0;
for (Method_map::const_iterator p = this->methods_.begin();
p != this->methods_.end();
++p)
if (!p->second->is_ambiguous())
++ret;
return ret;
}
// Class Named_type.
// Return the name of the type.
const std::string&
Named_type::name() const
{
return this->named_object_->name();
}
// Return the name of the type to use in an error message.
std::string
Named_type::message_name() const
{
return this->named_object_->message_name();
}
// Return the base type for this type. We have to be careful about
// circular type definitions, which are invalid but may be seen here.
Type*
Named_type::named_base()
{
if (this->seen_)
return this;
this->seen_ = true;
Type* ret = this->type_->base();
this->seen_ = false;
return ret;
}
const Type*
Named_type::named_base() const
{
if (this->seen_)
return this;
this->seen_ = true;
const Type* ret = this->type_->base();
this->seen_ = false;
return ret;
}
// Return whether this is an error type. We have to be careful about
// circular type definitions, which are invalid but may be seen here.
bool
Named_type::is_named_error_type() const
{
if (this->seen_)
return false;
this->seen_ = true;
bool ret = this->type_->is_error_type();
this->seen_ = false;
return ret;
}
// Whether this type is comparable. We have to be careful about
// circular type definitions.
bool
Named_type::named_type_is_comparable(std::string* reason) const
{
if (this->seen_)
return false;
this->seen_ = true;
bool ret = Type::are_compatible_for_comparison(true, this->type_,
this->type_, reason);
this->seen_ = false;
return ret;
}
// Add a method to this type.
Named_object*
Named_type::add_method(const std::string& name, Function* function)
{
go_assert(!this->is_alias_);
if (this->local_methods_ == NULL)
this->local_methods_ = new Bindings(NULL);
return this->local_methods_->add_function(name, NULL, function);
}
// Add a method declaration to this type.
Named_object*
Named_type::add_method_declaration(const std::string& name, Package* package,
Function_type* type,
Location location)
{
go_assert(!this->is_alias_);
if (this->local_methods_ == NULL)
this->local_methods_ = new Bindings(NULL);
return this->local_methods_->add_function_declaration(name, package, type,
location);
}
// Add an existing method to this type.
void
Named_type::add_existing_method(Named_object* no)
{
go_assert(!this->is_alias_);
if (this->local_methods_ == NULL)
this->local_methods_ = new Bindings(NULL);
this->local_methods_->add_named_object(no);
}
// Look for a local method NAME, and returns its named object, or NULL
// if not there.
Named_object*
Named_type::find_local_method(const std::string& name) const
{
if (this->is_error_)
return NULL;
if (this->is_alias_)
{
Named_type* nt = this->type_->named_type();
if (nt != NULL)
{
if (this->seen_alias_)
return NULL;
this->seen_alias_ = true;
Named_object* ret = nt->find_local_method(name);
this->seen_alias_ = false;
return ret;
}
return NULL;
}
if (this->local_methods_ == NULL)
return NULL;
return this->local_methods_->lookup(name);
}
// Return the list of local methods.
const Bindings*
Named_type::local_methods() const
{
if (this->is_error_)
return NULL;
if (this->is_alias_)
{
Named_type* nt = this->type_->named_type();
if (nt != NULL)
{
if (this->seen_alias_)
return NULL;
this->seen_alias_ = true;
const Bindings* ret = nt->local_methods();
this->seen_alias_ = false;
return ret;
}
return NULL;
}
return this->local_methods_;
}
// Return whether NAME is an unexported field or method, for better
// error reporting.
bool
Named_type::is_unexported_local_method(Gogo* gogo,
const std::string& name) const
{
if (this->is_error_)
return false;
if (this->is_alias_)
{
Named_type* nt = this->type_->named_type();
if (nt != NULL)
{
if (this->seen_alias_)
return false;
this->seen_alias_ = true;
bool ret = nt->is_unexported_local_method(gogo, name);
this->seen_alias_ = false;
return ret;
}
return false;
}
Bindings* methods = this->local_methods_;
if (methods != NULL)
{
for (Bindings::const_declarations_iterator p =
methods->begin_declarations();
p != methods->end_declarations();
++p)
{
if (Gogo::is_hidden_name(p->first)
&& name == Gogo::unpack_hidden_name(p->first)
&& gogo->pack_hidden_name(name, false) != p->first)
return true;
}
}
return false;
}
// Build the complete list of methods for this type, which means
// recursively including all methods for anonymous fields. Create all
// stub methods.
void
Named_type::finalize_methods(Gogo* gogo)
{
if (this->is_alias_)
return;
if (this->all_methods_ != NULL)
return;
if (this->local_methods_ != NULL
&& (this->points_to() != NULL || this->interface_type() != NULL))
{
const Bindings* lm = this->local_methods_;
for (Bindings::const_declarations_iterator p = lm->begin_declarations();
p != lm->end_declarations();
++p)
go_error_at(p->second->location(),
"invalid pointer or interface receiver type");
delete this->local_methods_;
this->local_methods_ = NULL;
return;
}
Type::finalize_methods(gogo, this, this->location_, &this->all_methods_);
}
// Return whether this type has any methods.
bool
Named_type::has_any_methods() const
{
if (this->is_error_)
return false;
if (this->is_alias_)
{
if (this->type_->named_type() != NULL)
{
if (this->seen_alias_)
return false;
this->seen_alias_ = true;
bool ret = this->type_->named_type()->has_any_methods();
this->seen_alias_ = false;
return ret;
}
if (this->type_->struct_type() != NULL)
return this->type_->struct_type()->has_any_methods();
return false;
}
return this->all_methods_ != NULL;
}
// Return the methods for this type.
const Methods*
Named_type::methods() const
{
if (this->is_error_)
return NULL;
if (this->is_alias_)
{
if (this->type_->named_type() != NULL)
{
if (this->seen_alias_)
return NULL;
this->seen_alias_ = true;
const Methods* ret = this->type_->named_type()->methods();
this->seen_alias_ = false;
return ret;
}
if (this->type_->struct_type() != NULL)
return this->type_->struct_type()->methods();
return NULL;
}
return this->all_methods_;
}
// Return the method NAME, or NULL if there isn't one or if it is
// ambiguous. Set *IS_AMBIGUOUS if the method exists but is
// ambiguous.
Method*
Named_type::method_function(const std::string& name, bool* is_ambiguous) const
{
if (this->is_error_)
return NULL;
if (this->is_alias_)
{
if (is_ambiguous != NULL)
*is_ambiguous = false;
if (this->type_->named_type() != NULL)
{
if (this->seen_alias_)
return NULL;
this->seen_alias_ = true;
Named_type* nt = this->type_->named_type();
Method* ret = nt->method_function(name, is_ambiguous);
this->seen_alias_ = false;
return ret;
}
if (this->type_->struct_type() != NULL)
return this->type_->struct_type()->method_function(name, is_ambiguous);
return NULL;
}
return Type::method_function(this->all_methods_, name, is_ambiguous);
}
// Return a pointer to the interface method table for this type for
// the interface INTERFACE. IS_POINTER is true if this is for a
// pointer to THIS.
Expression*
Named_type::interface_method_table(Interface_type* interface, bool is_pointer)
{
if (this->is_error_)
return Expression::make_error(this->location_);
if (this->is_alias_)
{
if (this->type_->named_type() != NULL)
{
if (this->seen_alias_)
return Expression::make_error(this->location_);
this->seen_alias_ = true;
Named_type* nt = this->type_->named_type();
Expression* ret = nt->interface_method_table(interface, is_pointer);
this->seen_alias_ = false;
return ret;
}
if (this->type_->struct_type() != NULL)
return this->type_->struct_type()->interface_method_table(interface,
is_pointer);
go_unreachable();
}
return Type::interface_method_table(this, interface, is_pointer,
&this->interface_method_tables_,
&this->pointer_interface_method_tables_);
}
// Look for a use of a complete type within another type. This is
// used to check that we don't try to use a type within itself.
class Find_type_use : public Traverse
{
public:
Find_type_use(Named_type* find_type)
: Traverse(traverse_types),
find_type_(find_type), found_(false)
{ }
// Whether we found the type.
bool
found() const
{ return this->found_; }
protected:
int
type(Type*);
private:
// The type we are looking for.
Named_type* find_type_;
// Whether we found the type.
bool found_;
};
// Check for FIND_TYPE in TYPE.
int
Find_type_use::type(Type* type)
{
if (type->named_type() != NULL && this->find_type_ == type->named_type())
{
this->found_ = true;
return TRAVERSE_EXIT;
}
// It's OK if we see a reference to the type in any type which is
// essentially a pointer: a pointer, a slice, a function, a map, or
// a channel.
if (type->points_to() != NULL
|| type->is_slice_type()
|| type->function_type() != NULL
|| type->map_type() != NULL
|| type->channel_type() != NULL)
return TRAVERSE_SKIP_COMPONENTS;
// For an interface, a reference to the type in a method type should
// be ignored, but we have to consider direct inheritance. When
// this is called, there may be cases of direct inheritance
// represented as a method with no name.
if (type->interface_type() != NULL)
{
const Typed_identifier_list* methods = type->interface_type()->methods();
if (methods != NULL)
{
for (Typed_identifier_list::const_iterator p = methods->begin();
p != methods->end();
++p)
{
if (p->name().empty())
{
if (Type::traverse(p->type(), this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
}
return TRAVERSE_SKIP_COMPONENTS;
}
// Otherwise, FIND_TYPE_ depends on TYPE, in the sense that we need
// to convert TYPE to the backend representation before we convert
// FIND_TYPE_.
if (type->named_type() != NULL)
{
switch (type->base()->classification())
{
case Type::TYPE_ERROR:
case Type::TYPE_BOOLEAN:
case Type::TYPE_INTEGER:
case Type::TYPE_FLOAT:
case Type::TYPE_COMPLEX:
case Type::TYPE_STRING:
case Type::TYPE_NIL:
break;
case Type::TYPE_ARRAY:
case Type::TYPE_STRUCT:
this->find_type_->add_dependency(type->named_type());
break;
case Type::TYPE_NAMED:
case Type::TYPE_FORWARD:
go_assert(saw_errors());
break;
case Type::TYPE_VOID:
case Type::TYPE_SINK:
case Type::TYPE_FUNCTION:
case Type::TYPE_POINTER:
case Type::TYPE_CALL_MULTIPLE_RESULT:
case Type::TYPE_MAP:
case Type::TYPE_CHANNEL:
case Type::TYPE_INTERFACE:
default:
go_unreachable();
}
}
return TRAVERSE_CONTINUE;
}
// Look for a circular reference of an alias.
class Find_alias : public Traverse
{
public:
Find_alias(Named_type* find_type)
: Traverse(traverse_types),
find_type_(find_type), found_(false)
{ }
// Whether we found the type.
bool
found() const
{ return this->found_; }
protected:
int
type(Type*);
private:
// The type we are looking for.
Named_type* find_type_;
// Whether we found the type.
bool found_;
};
int
Find_alias::type(Type* type)
{
Named_type* nt = type->named_type();
if (nt != NULL)
{
if (nt == this->find_type_)
{
this->found_ = true;
return TRAVERSE_EXIT;
}
// We started from `type T1 = T2`, where T1 is find_type_ and T2
// is, perhaps indirectly, the parameter TYPE. If TYPE is not
// an alias itself, it's OK if whatever T2 is defined as refers
// to T1.
if (!nt->is_alias())
return TRAVERSE_SKIP_COMPONENTS;
}
return TRAVERSE_CONTINUE;
}
// Verify that a named type does not refer to itself.
bool
Named_type::do_verify()
{
if (this->is_verified_)
return true;
this->is_verified_ = true;
if (this->is_error_)
return false;
if (this->is_alias_)
{
Find_alias find(this);
Type::traverse(this->type_, &find);
if (find.found())
{
go_error_at(this->location_, "invalid recursive alias %qs",
this->message_name().c_str());
this->is_error_ = true;
return false;
}
}
Find_type_use find(this);
Type::traverse(this->type_, &find);
if (find.found())
{
go_error_at(this->location_, "invalid recursive type %qs",
this->message_name().c_str());
this->is_error_ = true;
return false;
}
// Check whether any of the local methods overloads an existing
// struct field or interface method. We don't need to check the
// list of methods against itself: that is handled by the Bindings
// code.
if (this->local_methods_ != NULL)
{
Struct_type* st = this->type_->struct_type();
if (st != NULL)
{
for (Bindings::const_declarations_iterator p =
this->local_methods_->begin_declarations();
p != this->local_methods_->end_declarations();
++p)
{
const std::string& name(p->first);
if (st != NULL && st->find_local_field(name, NULL) != NULL)
{
go_error_at(p->second->location(),
"method %qs redeclares struct field name",
Gogo::message_name(name).c_str());
}
}
}
}
return true;
}
// Return whether this type is or contains a pointer.
bool
Named_type::do_has_pointer() const
{
if (this->seen_)
return false;
this->seen_ = true;
bool ret = this->type_->has_pointer();
this->seen_ = false;
return ret;
}
// Return whether comparisons for this type can use the identity
// function.
bool
Named_type::do_compare_is_identity(Gogo* gogo)
{
// We don't use this->seen_ here because compare_is_identity may
// call base() later, and that will mess up if seen_ is set here.
if (this->seen_in_compare_is_identity_)
return false;
this->seen_in_compare_is_identity_ = true;
bool ret = this->type_->compare_is_identity(gogo);
this->seen_in_compare_is_identity_ = false;
return ret;
}
// Return whether this type is reflexive--whether it is always equal
// to itself.
bool
Named_type::do_is_reflexive()
{
if (this->seen_in_compare_is_identity_)
return false;
this->seen_in_compare_is_identity_ = true;
bool ret = this->type_->is_reflexive();
this->seen_in_compare_is_identity_ = false;
return ret;
}
// Return whether this type needs a key update when used as a map key.
bool
Named_type::do_needs_key_update()
{
if (this->seen_in_compare_is_identity_)
return true;
this->seen_in_compare_is_identity_ = true;
bool ret = this->type_->needs_key_update();
this->seen_in_compare_is_identity_ = false;
return ret;
}
// Return a hash code. This is used for method lookup. We simply
// hash on the name itself.
unsigned int
Named_type::do_hash_for_method(Gogo* gogo) const
{
if (this->is_error_)
return 0;
// Aliases are handled in Type::hash_for_method.
go_assert(!this->is_alias_);
const std::string& name(this->named_object()->name());
unsigned int ret = Type::hash_string(name, 0);
// GOGO will be NULL here when called from Type_hash_identical.
// That is OK because that is only used for internal hash tables
// where we are going to be comparing named types for equality. In
// other cases, which are cases where the runtime is going to
// compare hash codes to see if the types are the same, we need to
// include the pkgpath in the hash.
if (gogo != NULL && !Gogo::is_hidden_name(name) && !this->is_builtin())
{
const Package* package = this->named_object()->package();
if (package == NULL)
ret = Type::hash_string(gogo->pkgpath(), ret);
else
ret = Type::hash_string(package->pkgpath(), ret);
}
return ret;
}
// Convert a named type to the backend representation. In order to
// get dependencies right, we fill in a dummy structure for this type,
// then convert all the dependencies, then complete this type. When
// this function is complete, the size of the type is known.
void
Named_type::convert(Gogo* gogo)
{
if (this->is_error_ || this->is_converted_)
return;
this->create_placeholder(gogo);
// If we are called to turn unsafe.Sizeof into a constant, we may
// not have verified the type yet. We have to make sure it is
// verified, since that sets the list of dependencies.
this->verify();
// Convert all the dependencies. If they refer indirectly back to
// this type, they will pick up the intermediate representation we just
// created.
for (std::vector<Named_type*>::const_iterator p = this->dependencies_.begin();
p != this->dependencies_.end();
++p)
(*p)->convert(gogo);
// Complete this type.
Btype* bt = this->named_btype_;
Type* base = this->type_->base();
switch (base->classification())
{
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_NIL:
break;
case TYPE_MAP:
case TYPE_CHANNEL:
break;
case TYPE_FUNCTION:
case TYPE_POINTER:
// The size of these types is already correct. We don't worry
// about filling them in until later, when we also track
// circular references.
break;
case TYPE_STRUCT:
{
std::vector<Backend::Btyped_identifier> bfields;
get_backend_struct_fields(gogo, base->struct_type()->fields(),
true, &bfields);
if (!gogo->backend()->set_placeholder_struct_type(bt, bfields))
bt = gogo->backend()->error_type();
}
break;
case TYPE_ARRAY:
// Slice types were completed in create_placeholder.
if (!base->is_slice_type())
{
Btype* bet = base->array_type()->get_backend_element(gogo, true);
Bexpression* blen = base->array_type()->get_backend_length(gogo);
if (!gogo->backend()->set_placeholder_array_type(bt, bet, blen))
bt = gogo->backend()->error_type();
}
break;
case TYPE_INTERFACE:
// Interface types were completed in create_placeholder.
break;
case TYPE_ERROR:
return;
default:
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
case TYPE_NAMED:
case TYPE_FORWARD:
go_unreachable();
}
this->named_btype_ = bt;
this->is_converted_ = true;
this->is_placeholder_ = false;
}
// Create the placeholder for a named type. This is the first step in
// converting to the backend representation.
void
Named_type::create_placeholder(Gogo* gogo)
{
if (this->is_error_)
this->named_btype_ = gogo->backend()->error_type();
if (this->named_btype_ != NULL)
return;
// Create the structure for this type. Note that because we call
// base() here, we don't attempt to represent a named type defined
// as another named type. Instead both named types will point to
// different base representations.
Type* base = this->type_->base();
Btype* bt;
bool set_name = true;
switch (base->classification())
{
case TYPE_ERROR:
this->is_error_ = true;
this->named_btype_ = gogo->backend()->error_type();
return;
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_NIL:
// These are simple basic types, we can just create them
// directly.
bt = Type::get_named_base_btype(gogo, base);
break;
case TYPE_MAP:
case TYPE_CHANNEL:
// All maps and channels have the same backend representation.
bt = Type::get_named_base_btype(gogo, base);
break;
case TYPE_FUNCTION:
case TYPE_POINTER:
{
bool for_function = base->classification() == TYPE_FUNCTION;
bt = gogo->backend()->placeholder_pointer_type(this->name(),
this->location_,
for_function);
set_name = false;
}
break;
case TYPE_STRUCT:
bt = gogo->backend()->placeholder_struct_type(this->name(),
this->location_);
this->is_placeholder_ = true;
set_name = false;
break;
case TYPE_ARRAY:
if (base->is_slice_type())
bt = gogo->backend()->placeholder_struct_type(this->name(),
this->location_);
else
{
bt = gogo->backend()->placeholder_array_type(this->name(),
this->location_);
this->is_placeholder_ = true;
}
set_name = false;
break;
case TYPE_INTERFACE:
if (base->interface_type()->is_empty())
bt = Interface_type::get_backend_empty_interface_type(gogo);
else
{
bt = gogo->backend()->placeholder_struct_type(this->name(),
this->location_);
set_name = false;
}
break;
default:
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
case TYPE_NAMED:
case TYPE_FORWARD:
go_unreachable();
}
if (set_name)
bt = gogo->backend()->named_type(this->name(), bt, this->location_);
this->named_btype_ = bt;
if (base->is_slice_type())
{
// We do not record slices as dependencies of other types,
// because we can fill them in completely here with the final
// size.
std::vector<Backend::Btyped_identifier> bfields;
get_backend_slice_fields(gogo, base->array_type(), true, &bfields);
if (!gogo->backend()->set_placeholder_struct_type(bt, bfields))
this->named_btype_ = gogo->backend()->error_type();
}
else if (base->interface_type() != NULL
&& !base->interface_type()->is_empty())
{
// We do not record interfaces as dependencies of other types,
// because we can fill them in completely here with the final
// size.
std::vector<Backend::Btyped_identifier> bfields;
get_backend_interface_fields(gogo, base->interface_type(), true,
&bfields);
if (!gogo->backend()->set_placeholder_struct_type(bt, bfields))
this->named_btype_ = gogo->backend()->error_type();
}
}
// Get the backend representation for a named type.
Btype*
Named_type::do_get_backend(Gogo* gogo)
{
if (this->is_error_)
return gogo->backend()->error_type();
Btype* bt = this->named_btype_;
if (!gogo->named_types_are_converted())
{
// We have not completed converting named types. NAMED_BTYPE_
// is a placeholder and we shouldn't do anything further.
if (bt != NULL)
return bt;
// We don't build dependencies for types whose sizes do not
// change or are not relevant, so we may see them here while
// converting types.
this->create_placeholder(gogo);
bt = this->named_btype_;
go_assert(bt != NULL);
return bt;
}
// We are not converting types. This should only be called if the
// type has already been converted.
if (!this->is_converted_)
{
go_assert(saw_errors());
return gogo->backend()->error_type();
}
go_assert(bt != NULL);
// Complete the backend representation.
Type* base = this->type_->base();
Btype* bt1;
switch (base->classification())
{
case TYPE_ERROR:
return gogo->backend()->error_type();
case TYPE_VOID:
case TYPE_BOOLEAN:
case TYPE_INTEGER:
case TYPE_FLOAT:
case TYPE_COMPLEX:
case TYPE_STRING:
case TYPE_NIL:
case TYPE_MAP:
case TYPE_CHANNEL:
return bt;
case TYPE_STRUCT:
if (!this->seen_in_get_backend_)
{
this->seen_in_get_backend_ = true;
base->struct_type()->finish_backend_fields(gogo);
this->seen_in_get_backend_ = false;
}
return bt;
case TYPE_ARRAY:
if (!this->seen_in_get_backend_)
{
this->seen_in_get_backend_ = true;
base->array_type()->finish_backend_element(gogo);
this->seen_in_get_backend_ = false;
}
return bt;
case TYPE_INTERFACE:
if (!this->seen_in_get_backend_)
{
this->seen_in_get_backend_ = true;
base->interface_type()->finish_backend_methods(gogo);
this->seen_in_get_backend_ = false;
}
return bt;
case TYPE_FUNCTION:
// Don't build a circular data structure. GENERIC can't handle
// it.
if (this->seen_in_get_backend_)
{
this->is_circular_ = true;
return gogo->backend()->circular_pointer_type(bt, true);
}
this->seen_in_get_backend_ = true;
bt1 = Type::get_named_base_btype(gogo, base);
this->seen_in_get_backend_ = false;
if (this->is_circular_)
bt1 = gogo->backend()->circular_pointer_type(bt, true);
if (!gogo->backend()->set_placeholder_pointer_type(bt, bt1))
bt = gogo->backend()->error_type();
return bt;
case TYPE_POINTER:
// Don't build a circular data structure. GENERIC can't handle
// it.
if (this->seen_in_get_backend_)
{
this->is_circular_ = true;
return gogo->backend()->circular_pointer_type(bt, false);
}
this->seen_in_get_backend_ = true;
bt1 = Type::get_named_base_btype(gogo, base);
this->seen_in_get_backend_ = false;
if (this->is_circular_)
bt1 = gogo->backend()->circular_pointer_type(bt, false);
if (!gogo->backend()->set_placeholder_pointer_type(bt, bt1))
bt = gogo->backend()->error_type();
return bt;
default:
case TYPE_SINK:
case TYPE_CALL_MULTIPLE_RESULT:
case TYPE_NAMED:
case TYPE_FORWARD:
go_unreachable();
}
go_unreachable();
}
// Build a type descriptor for a named type.
Expression*
Named_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
if (this->is_error_)
return Expression::make_error(this->location_);
if (name == NULL && this->is_alias_)
{
if (this->seen_alias_)
return Expression::make_error(this->location_);
this->seen_alias_ = true;
Expression* ret = this->type_->type_descriptor(gogo, NULL);
this->seen_alias_ = false;
return ret;
}
// If NAME is not NULL, then we don't really want the type
// descriptor for this type; we want the descriptor for the
// underlying type, giving it the name NAME.
return this->named_type_descriptor(gogo, this->type_,
name == NULL ? this : name);
}
// Add to the reflection string. This is used mostly for the name of
// the type used in a type descriptor, not for actual reflection
// strings.
void
Named_type::do_reflection(Gogo* gogo, std::string* ret) const
{
this->append_reflection_type_name(gogo, false, ret);
}
// Add to the reflection string. For an alias we normally use the
// real name, but if USE_ALIAS is true we use the alias name itself.
void
Named_type::append_reflection_type_name(Gogo* gogo, bool use_alias,
std::string* ret) const
{
if (this->is_error_)
return;
if (this->is_alias_ && !use_alias)
{
if (this->seen_alias_)
return;
this->seen_alias_ = true;
this->append_reflection(this->type_, gogo, ret);
this->seen_alias_ = false;
return;
}
if (!this->is_builtin())
{
// When -fgo-pkgpath or -fgo-prefix is specified, we use it to
// make a unique reflection string, so that the type
// canonicalization in the reflect package will work. In order
// to be compatible with the gc compiler, we put tabs into the
// package path, so that the reflect methods can discard it.
const Package* package = this->named_object_->package();
ret->push_back('\t');
ret->append(package != NULL
? package->pkgpath_symbol()
: gogo->pkgpath_symbol());
ret->push_back('\t');
ret->append(package != NULL
? package->package_name()
: gogo->package_name());
ret->push_back('.');
}
if (this->in_function_ != NULL)
{
ret->push_back('\t');
const Typed_identifier* rcvr =
this->in_function_->func_value()->type()->receiver();
if (rcvr != NULL)
{
Named_type* rcvr_type = rcvr->type()->deref()->named_type();
ret->append(Gogo::unpack_hidden_name(rcvr_type->name()));
ret->push_back('.');
}
ret->append(Gogo::unpack_hidden_name(this->in_function_->name()));
ret->push_back('$');
if (this->in_function_index_ > 0)
{
char buf[30];
snprintf(buf, sizeof buf, "%u", this->in_function_index_);
ret->append(buf);
ret->push_back('$');
}
ret->push_back('\t');
}
ret->append(Gogo::unpack_hidden_name(this->named_object_->name()));
}
// Export the type. This is called to export a global type.
void
Named_type::export_named_type(Export* exp, const std::string&) const
{
// We don't need to write the name of the type here, because it will
// be written by Export::write_type anyhow.
exp->write_c_string("type ");
exp->write_type(this);
exp->write_c_string(";\n");
}
// Import a named type.
void
Named_type::import_named_type(Import* imp, Named_type** ptype)
{
imp->require_c_string("type ");
Type *type = imp->read_type();
*ptype = type->named_type();
go_assert(*ptype != NULL);
imp->require_c_string(";\n");
}
// Export the type when it is referenced by another type. In this
// case Export::export_type will already have issued the name.
void
Named_type::do_export(Export* exp) const
{
exp->write_type(this->type_);
// To save space, we only export the methods directly attached to
// this type.
Bindings* methods = this->local_methods_;
if (methods == NULL)
return;
exp->write_c_string("\n");
for (Bindings::const_definitions_iterator p = methods->begin_definitions();
p != methods->end_definitions();
++p)
{
exp->write_c_string(" ");
(*p)->export_named_object(exp);
}
for (Bindings::const_declarations_iterator p = methods->begin_declarations();
p != methods->end_declarations();
++p)
{
if (p->second->is_function_declaration())
{
exp->write_c_string(" ");
p->second->export_named_object(exp);
}
}
}
// Make a named type.
Named_type*
Type::make_named_type(Named_object* named_object, Type* type,
Location location)
{
return new Named_type(named_object, type, location);
}
// Finalize the methods for TYPE. It will be a named type or a struct
// type. This sets *ALL_METHODS to the list of methods, and builds
// all required stubs.
void
Type::finalize_methods(Gogo* gogo, const Type* type, Location location,
Methods** all_methods)
{
*all_methods = new Methods();
std::vector<const Named_type*> seen;
Type::add_methods_for_type(type, NULL, 0, false, false, &seen, *all_methods);
if ((*all_methods)->empty())
{
delete *all_methods;
*all_methods = NULL;
}
Type::build_stub_methods(gogo, type, *all_methods, location);
}
// Add the methods for TYPE to *METHODS. FIELD_INDEXES is used to
// build up the struct field indexes as we go. DEPTH is the depth of
// the field within TYPE. IS_EMBEDDED_POINTER is true if we are
// adding these methods for an anonymous field with pointer type.
// NEEDS_STUB_METHOD is true if we need to use a stub method which
// calls the real method. TYPES_SEEN is used to avoid infinite
// recursion.
void
Type::add_methods_for_type(const Type* type,
const Method::Field_indexes* field_indexes,
unsigned int depth,
bool is_embedded_pointer,
bool needs_stub_method,
std::vector<const Named_type*>* seen,
Methods* methods)
{
// Pointer types may not have methods.
if (type->points_to() != NULL)
return;
const Named_type* nt = type->named_type();
if (nt != NULL)
{
for (std::vector<const Named_type*>::const_iterator p = seen->begin();
p != seen->end();
++p)
{
if (*p == nt)
return;
}
seen->push_back(nt);
Type::add_local_methods_for_type(nt, field_indexes, depth,
is_embedded_pointer, needs_stub_method,
methods);
}
Type::add_embedded_methods_for_type(type, field_indexes, depth,
is_embedded_pointer, needs_stub_method,
seen, methods);
// If we are called with depth > 0, then we are looking at an
// anonymous field of a struct. If such a field has interface type,
// then we need to add the interface methods. We don't want to add
// them when depth == 0, because we will already handle them
// following the usual rules for an interface type.
if (depth > 0)
Type::add_interface_methods_for_type(type, field_indexes, depth, methods);
if (nt != NULL)
seen->pop_back();
}
// Add the local methods for the named type NT to *METHODS. The
// parameters are as for add_methods_to_type.
void
Type::add_local_methods_for_type(const Named_type* nt,
const Method::Field_indexes* field_indexes,
unsigned int depth,
bool is_embedded_pointer,
bool needs_stub_method,
Methods* methods)
{
const Bindings* local_methods = nt->local_methods();
if (local_methods == NULL)
return;
for (Bindings::const_declarations_iterator p =
local_methods->begin_declarations();
p != local_methods->end_declarations();
++p)
{
Named_object* no = p->second;
bool is_value_method = (is_embedded_pointer
|| !Type::method_expects_pointer(no));
Method* m = new Named_method(no, field_indexes, depth, is_value_method,
(needs_stub_method || depth > 0));
if (!methods->insert(no->name(), m))
delete m;
}
}
// Add the embedded methods for TYPE to *METHODS. These are the
// methods attached to anonymous fields. The parameters are as for
// add_methods_to_type.
void
Type::add_embedded_methods_for_type(const Type* type,
const Method::Field_indexes* field_indexes,
unsigned int depth,
bool is_embedded_pointer,
bool needs_stub_method,
std::vector<const Named_type*>* seen,
Methods* methods)
{
// Look for anonymous fields in TYPE. TYPE has fields if it is a
// struct.
const Struct_type* st = type->struct_type();
if (st == NULL)
return;
const Struct_field_list* fields = st->fields();
if (fields == NULL)
return;
unsigned int i = 0;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf, ++i)
{
if (!pf->is_anonymous())
continue;
Type* ftype = pf->type();
bool is_pointer = false;
if (ftype->points_to() != NULL)
{
ftype = ftype->points_to();
is_pointer = true;
}
Named_type* fnt = ftype->named_type();
if (fnt == NULL)
{
// This is an error, but it will be diagnosed elsewhere.
continue;
}
Method::Field_indexes* sub_field_indexes = new Method::Field_indexes();
sub_field_indexes->next = field_indexes;
sub_field_indexes->field_index = i;
Methods tmp_methods;
Type::add_methods_for_type(fnt, sub_field_indexes, depth + 1,
(is_embedded_pointer || is_pointer),
(needs_stub_method
|| is_pointer
|| i > 0),
seen,
&tmp_methods);
// Check if there are promoted methods that conflict with field names and
// don't add them to the method map.
for (Methods::const_iterator p = tmp_methods.begin();
p != tmp_methods.end();
++p)
{
bool found = false;
for (Struct_field_list::const_iterator fp = fields->begin();
fp != fields->end();
++fp)
{
if (fp->field_name() == p->first)
{
found = true;
break;
}
}
if (!found &&
!methods->insert(p->first, p->second))
delete p->second;
}
}
}
// If TYPE is an interface type, then add its method to *METHODS.
// This is for interface methods attached to an anonymous field. The
// parameters are as for add_methods_for_type.
void
Type::add_interface_methods_for_type(const Type* type,
const Method::Field_indexes* field_indexes,
unsigned int depth,
Methods* methods)
{
const Interface_type* it = type->interface_type();
if (it == NULL)
return;
const Typed_identifier_list* imethods = it->methods();
if (imethods == NULL)
return;
for (Typed_identifier_list::const_iterator pm = imethods->begin();
pm != imethods->end();
++pm)
{
Function_type* fntype = pm->type()->function_type();
if (fntype == NULL)
{
// This is an error, but it should be reported elsewhere
// when we look at the methods for IT.
continue;
}
go_assert(!fntype->is_method());
fntype = fntype->copy_with_receiver(const_cast<Type*>(type));
Method* m = new Interface_method(pm->name(), pm->location(), fntype,
field_indexes, depth);
if (!methods->insert(pm->name(), m))
delete m;
}
}
// Build stub methods for TYPE as needed. METHODS is the set of
// methods for the type. A stub method may be needed when a type
// inherits a method from an anonymous field. When we need the
// address of the method, as in a type descriptor, we need to build a
// little stub which does the required field dereferences and jumps to
// the real method. LOCATION is the location of the type definition.
void
Type::build_stub_methods(Gogo* gogo, const Type* type, const Methods* methods,
Location location)
{
if (methods == NULL)
return;
for (Methods::const_iterator p = methods->begin();
p != methods->end();
++p)
{
Method* m = p->second;
if (m->is_ambiguous() || !m->needs_stub_method())
continue;
const std::string& name(p->first);
// Build a stub method.
const Function_type* fntype = m->type();
static unsigned int counter;
char buf[100];
snprintf(buf, sizeof buf, "$this%u", counter);
++counter;
Type* receiver_type = const_cast<Type*>(type);
if (!m->is_value_method())
receiver_type = Type::make_pointer_type(receiver_type);
Location receiver_location = m->receiver_location();
Typed_identifier* receiver = new Typed_identifier(buf, receiver_type,
receiver_location);
const Typed_identifier_list* fnparams = fntype->parameters();
Typed_identifier_list* stub_params;
if (fnparams == NULL || fnparams->empty())
stub_params = NULL;
else
{
// We give each stub parameter a unique name.
stub_params = new Typed_identifier_list();
for (Typed_identifier_list::const_iterator pp = fnparams->begin();
pp != fnparams->end();
++pp)
{
char pbuf[100];
snprintf(pbuf, sizeof pbuf, "$p%u", counter);
stub_params->push_back(Typed_identifier(pbuf, pp->type(),
pp->location()));
++counter;
}
}
const Typed_identifier_list* fnresults = fntype->results();
Typed_identifier_list* stub_results;
if (fnresults == NULL || fnresults->empty())
stub_results = NULL;
else
{
// We create the result parameters without any names, since
// we won't refer to them.
stub_results = new Typed_identifier_list();
for (Typed_identifier_list::const_iterator pr = fnresults->begin();
pr != fnresults->end();
++pr)
stub_results->push_back(Typed_identifier("", pr->type(),
pr->location()));
}
Function_type* stub_type = Type::make_function_type(receiver,
stub_params,
stub_results,
fntype->location());
if (fntype->is_varargs())
stub_type->set_is_varargs();
// We only create the function in the package which creates the
// type.
const Package* package;
if (type->named_type() == NULL)
package = NULL;
else
package = type->named_type()->named_object()->package();
std::string stub_name = gogo->stub_method_name(package, name);
Named_object* stub;
if (package != NULL)
stub = Named_object::make_function_declaration(stub_name, package,
stub_type, location);
else
{
stub = gogo->start_function(stub_name, stub_type, false,
fntype->location());
Type::build_one_stub_method(gogo, m, buf, stub_params,
fntype->is_varargs(), location);
gogo->finish_function(fntype->location());
if (type->named_type() == NULL && stub->is_function())
stub->func_value()->set_is_unnamed_type_stub_method();
if (m->nointerface() && stub->is_function())
stub->func_value()->set_nointerface();
}
m->set_stub_object(stub);
}
}
// Build a stub method which adjusts the receiver as required to call
// METHOD. RECEIVER_NAME is the name we used for the receiver.
// PARAMS is the list of function parameters.
void
Type::build_one_stub_method(Gogo* gogo, Method* method,
const char* receiver_name,
const Typed_identifier_list* params,
bool is_varargs,
Location location)
{
Named_object* receiver_object = gogo->lookup(receiver_name, NULL);
go_assert(receiver_object != NULL);
Expression* expr = Expression::make_var_reference(receiver_object, location);
expr = Type::apply_field_indexes(expr, method->field_indexes(), location);
if (expr->type()->points_to() == NULL)
expr = Expression::make_unary(OPERATOR_AND, expr, location);
Expression_list* arguments;
if (params == NULL || params->empty())
arguments = NULL;
else
{
arguments = new Expression_list();
for (Typed_identifier_list::const_iterator p = params->begin();
p != params->end();
++p)
{
Named_object* param = gogo->lookup(p->name(), NULL);
go_assert(param != NULL);
Expression* param_ref = Expression::make_var_reference(param,
location);
arguments->push_back(param_ref);
}
}
Expression* func = method->bind_method(expr, location);
go_assert(func != NULL);
Call_expression* call = Expression::make_call(func, arguments, is_varargs,
location);
gogo->add_statement(Statement::make_return_from_call(call, location));
}
// Apply FIELD_INDEXES to EXPR. The field indexes have to be applied
// in reverse order.
Expression*
Type::apply_field_indexes(Expression* expr,
const Method::Field_indexes* field_indexes,
Location location)
{
if (field_indexes == NULL)
return expr;
expr = Type::apply_field_indexes(expr, field_indexes->next, location);
Struct_type* stype = expr->type()->deref()->struct_type();
go_assert(stype != NULL
&& field_indexes->field_index < stype->field_count());
if (expr->type()->struct_type() == NULL)
{
go_assert(expr->type()->points_to() != NULL);
expr = Expression::make_dereference(expr, Expression::NIL_CHECK_DEFAULT,
location);
go_assert(expr->type()->struct_type() == stype);
}
return Expression::make_field_reference(expr, field_indexes->field_index,
location);
}
// Return whether NO is a method for which the receiver is a pointer.
bool
Type::method_expects_pointer(const Named_object* no)
{
const Function_type *fntype;
if (no->is_function())
fntype = no->func_value()->type();
else if (no->is_function_declaration())
fntype = no->func_declaration_value()->type();
else
go_unreachable();
return fntype->receiver()->type()->points_to() != NULL;
}
// Given a set of methods for a type, METHODS, return the method NAME,
// or NULL if there isn't one or if it is ambiguous. If IS_AMBIGUOUS
// is not NULL, then set *IS_AMBIGUOUS to true if the method exists
// but is ambiguous (and return NULL).
Method*
Type::method_function(const Methods* methods, const std::string& name,
bool* is_ambiguous)
{
if (is_ambiguous != NULL)
*is_ambiguous = false;
if (methods == NULL)
return NULL;
Methods::const_iterator p = methods->find(name);
if (p == methods->end())
return NULL;
Method* m = p->second;
if (m->is_ambiguous())
{
if (is_ambiguous != NULL)
*is_ambiguous = true;
return NULL;
}
return m;
}
// Return a pointer to the interface method table for TYPE for the
// interface INTERFACE.
Expression*
Type::interface_method_table(Type* type,
Interface_type *interface,
bool is_pointer,
Interface_method_tables** method_tables,
Interface_method_tables** pointer_tables)
{
go_assert(!interface->is_empty());
Interface_method_tables** pimt = is_pointer ? method_tables : pointer_tables;
if (*pimt == NULL)
*pimt = new Interface_method_tables(5);
std::pair<Interface_type*, Expression*> val(interface, NULL);
std::pair<Interface_method_tables::iterator, bool> ins = (*pimt)->insert(val);
Location loc = Linemap::predeclared_location();
if (ins.second)
{
// This is a new entry in the hash table.
go_assert(ins.first->second == NULL);
ins.first->second =
Expression::make_interface_mtable_ref(interface, type, is_pointer, loc);
}
return Expression::make_unary(OPERATOR_AND, ins.first->second, loc);
}
// Look for field or method NAME for TYPE. Return an Expression for
// the field or method bound to EXPR. If there is no such field or
// method, give an appropriate error and return an error expression.
Expression*
Type::bind_field_or_method(Gogo* gogo, const Type* type, Expression* expr,
const std::string& name,
Location location)
{
if (type->deref()->is_error_type())
return Expression::make_error(location);
const Named_type* nt = type->deref()->named_type();
const Struct_type* st = type->deref()->struct_type();
const Interface_type* it = type->interface_type();
// If this is a pointer to a pointer, then it is possible that the
// pointed-to type has methods.
bool dereferenced = false;
if (nt == NULL
&& st == NULL
&& it == NULL
&& type->points_to() != NULL
&& type->points_to()->points_to() != NULL)
{
expr = Expression::make_dereference(expr, Expression::NIL_CHECK_DEFAULT,
location);
type = type->points_to();
if (type->deref()->is_error_type())
return Expression::make_error(location);
nt = type->points_to()->named_type();
st = type->points_to()->struct_type();
dereferenced = true;
}
bool receiver_can_be_pointer = (expr->type()->points_to() != NULL
|| expr->is_addressable());
std::vector<const Named_type*> seen;
bool is_method = false;
bool found_pointer_method = false;
std::string ambig1;
std::string ambig2;
if (Type::find_field_or_method(type, name, receiver_can_be_pointer,
&seen, NULL, &is_method,
&found_pointer_method, &ambig1, &ambig2))
{
Expression* ret;
if (!is_method)
{
go_assert(st != NULL);
if (type->struct_type() == NULL)
{
if (dereferenced)
{
go_error_at(location, "pointer type has no field %qs",
Gogo::message_name(name).c_str());
return Expression::make_error(location);
}
go_assert(type->points_to() != NULL);
expr = Expression::make_dereference(expr,
Expression::NIL_CHECK_DEFAULT,
location);
go_assert(expr->type()->struct_type() == st);
}
ret = st->field_reference(expr, name, location);
if (ret == NULL)
{
go_error_at(location, "type has no field %qs",
Gogo::message_name(name).c_str());
return Expression::make_error(location);
}
}
else if (it != NULL && it->find_method(name) != NULL)
ret = Expression::make_interface_field_reference(expr, name,
location);
else
{
Method* m;
if (nt != NULL)
m = nt->method_function(name, NULL);
else if (st != NULL)
m = st->method_function(name, NULL);
else
go_unreachable();
go_assert(m != NULL);
if (dereferenced)
{
go_error_at(location,
"calling method %qs requires explicit dereference",
Gogo::message_name(name).c_str());
return Expression::make_error(location);
}
if (!m->is_value_method() && expr->type()->points_to() == NULL)
expr = Expression::make_unary(OPERATOR_AND, expr, location);
ret = m->bind_method(expr, location);
}
go_assert(ret != NULL);
return ret;
}
else
{
if (Gogo::is_erroneous_name(name))
{
// An error was already reported.
}
else if (!ambig1.empty())
go_error_at(location, "%qs is ambiguous via %qs and %qs",
Gogo::message_name(name).c_str(), ambig1.c_str(),
ambig2.c_str());
else if (found_pointer_method)
go_error_at(location, "method requires a pointer receiver");
else if (nt == NULL && st == NULL && it == NULL)
go_error_at(location,
("reference to field %qs in object which "
"has no fields or methods"),
Gogo::message_name(name).c_str());
else
{
bool is_unexported;
// The test for 'a' and 'z' is to handle builtin names,
// which are not hidden.
if (!Gogo::is_hidden_name(name) && (name[0] < 'a' || name[0] > 'z'))
is_unexported = false;
else
{
std::string unpacked = Gogo::unpack_hidden_name(name);
seen.clear();
is_unexported = Type::is_unexported_field_or_method(gogo, type,
unpacked,
&seen);
}
if (is_unexported)
go_error_at(location, "reference to unexported field or method %qs",
Gogo::message_name(name).c_str());
else
go_error_at(location, "reference to undefined field or method %qs",
Gogo::message_name(name).c_str());
}
return Expression::make_error(location);
}
}
// Look in TYPE for a field or method named NAME, return true if one
// is found. This looks through embedded anonymous fields and handles
// ambiguity. If a method is found, sets *IS_METHOD to true;
// otherwise, if a field is found, set it to false. If
// RECEIVER_CAN_BE_POINTER is false, then the receiver is a value
// whose address can not be taken. SEEN is used to avoid infinite
// recursion on invalid types.
// When returning false, this sets *FOUND_POINTER_METHOD if we found a
// method we couldn't use because it requires a pointer. LEVEL is
// used for recursive calls, and can be NULL for a non-recursive call.
// When this function returns false because it finds that the name is
// ambiguous, it will store a path to the ambiguous names in *AMBIG1
// and *AMBIG2. If the name is not found at all, *AMBIG1 and *AMBIG2
// will be unchanged.
// This function just returns whether or not there is a field or
// method, and whether it is a field or method. It doesn't build an
// expression to refer to it. If it is a method, we then look in the
// list of all methods for the type. If it is a field, the search has
// to be done again, looking only for fields, and building up the
// expression as we go.
bool
Type::find_field_or_method(const Type* type,
const std::string& name,
bool receiver_can_be_pointer,
std::vector<const Named_type*>* seen,
int* level,
bool* is_method,
bool* found_pointer_method,
std::string* ambig1,
std::string* ambig2)
{
// Named types can have locally defined methods.
const Named_type* nt = type->unalias()->named_type();
if (nt == NULL && type->points_to() != NULL)
nt = type->points_to()->unalias()->named_type();
if (nt != NULL)
{
Named_object* no = nt->find_local_method(name);
if (no != NULL)
{
if (receiver_can_be_pointer || !Type::method_expects_pointer(no))
{
*is_method = true;
return true;
}
// Record that we have found a pointer method in order to
// give a better error message if we don't find anything
// else.
*found_pointer_method = true;
}
for (std::vector<const Named_type*>::const_iterator p = seen->begin();
p != seen->end();
++p)
{
if (*p == nt)
{
// We've already seen this type when searching for methods.
return false;
}
}
}
// Interface types can have methods.
const Interface_type* it = type->interface_type();
if (it != NULL && it->find_method(name) != NULL)
{
*is_method = true;
return true;
}
// Struct types can have fields. They can also inherit fields and
// methods from anonymous fields.
const Struct_type* st = type->deref()->struct_type();
if (st == NULL)
return false;
const Struct_field_list* fields = st->fields();
if (fields == NULL)
return false;
if (nt != NULL)
seen->push_back(nt);
int found_level = 0;
bool found_is_method = false;
std::string found_ambig1;
std::string found_ambig2;
const Struct_field* found_parent = NULL;
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (pf->is_field_name(name))
{
*is_method = false;
if (nt != NULL)
seen->pop_back();
return true;
}
if (!pf->is_anonymous())
continue;
if (pf->type()->deref()->is_error_type()
|| pf->type()->deref()->is_undefined())
continue;
Named_type* fnt = pf->type()->named_type();
if (fnt == NULL)
fnt = pf->type()->deref()->named_type();
go_assert(fnt != NULL);
// Methods with pointer receivers on embedded field are
// inherited by the pointer to struct, and also by the struct
// type if the field itself is a pointer.
bool can_be_pointer = (receiver_can_be_pointer
|| pf->type()->points_to() != NULL);
int sublevel = level == NULL ? 1 : *level + 1;
bool sub_is_method;
std::string subambig1;
std::string subambig2;
bool subfound = Type::find_field_or_method(fnt,
name,
can_be_pointer,
seen,
&sublevel,
&sub_is_method,
found_pointer_method,
&subambig1,
&subambig2);
if (!subfound)
{
if (!subambig1.empty())
{
// The name was found via this field, but is ambiguous.
// if the ambiguity is lower or at the same level as
// anything else we have already found, then we want to
// pass the ambiguity back to the caller.
if (found_level == 0 || sublevel <= found_level)
{
found_ambig1 = (Gogo::message_name(pf->field_name())
+ '.' + subambig1);
found_ambig2 = (Gogo::message_name(pf->field_name())
+ '.' + subambig2);
found_level = sublevel;
}
}
}
else
{
// The name was found via this field. Use the level to see
// if we want to use this one, or whether it introduces an
// ambiguity.
if (found_level == 0 || sublevel < found_level)
{
found_level = sublevel;
found_is_method = sub_is_method;
found_ambig1.clear();
found_ambig2.clear();
found_parent = &*pf;
}
else if (sublevel > found_level)
;
else if (found_ambig1.empty())
{
// We found an ambiguity.
go_assert(found_parent != NULL);
found_ambig1 = Gogo::message_name(found_parent->field_name());
found_ambig2 = Gogo::message_name(pf->field_name());
}
else
{
// We found an ambiguity, but we already know of one.
// Just report the earlier one.
}
}
}
// Here if we didn't find anything FOUND_LEVEL is 0. If we found
// something ambiguous, FOUND_LEVEL is not 0 and FOUND_AMBIG1 and
// FOUND_AMBIG2 are not empty. If we found the field, FOUND_LEVEL
// is not 0 and FOUND_AMBIG1 and FOUND_AMBIG2 are empty.
if (nt != NULL)
seen->pop_back();
if (found_level == 0)
return false;
else if (found_is_method
&& type->named_type() != NULL
&& type->points_to() != NULL)
{
// If this is a method inherited from a struct field in a named pointer
// type, it is invalid to automatically dereference the pointer to the
// struct to find this method.
if (level != NULL)
*level = found_level;
*is_method = true;
return false;
}
else if (!found_ambig1.empty())
{
go_assert(!found_ambig1.empty());
ambig1->assign(found_ambig1);
ambig2->assign(found_ambig2);
if (level != NULL)
*level = found_level;
return false;
}
else
{
if (level != NULL)
*level = found_level;
*is_method = found_is_method;
return true;
}
}
// Return whether NAME is an unexported field or method for TYPE.
bool
Type::is_unexported_field_or_method(Gogo* gogo, const Type* type,
const std::string& name,
std::vector<const Named_type*>* seen)
{
const Named_type* nt = type->named_type();
if (nt == NULL)
nt = type->deref()->named_type();
if (nt != NULL)
{
if (nt->is_unexported_local_method(gogo, name))
return true;
for (std::vector<const Named_type*>::const_iterator p = seen->begin();
p != seen->end();
++p)
{
if (*p == nt)
{
// We've already seen this type.
return false;
}
}
}
const Interface_type* it = type->interface_type();
if (it != NULL && it->is_unexported_method(gogo, name))
return true;
type = type->deref();
const Struct_type* st = type->struct_type();
if (st != NULL && st->is_unexported_local_field(gogo, name))
return true;
if (st == NULL)
return false;
const Struct_field_list* fields = st->fields();
if (fields == NULL)
return false;
if (nt != NULL)
seen->push_back(nt);
for (Struct_field_list::const_iterator pf = fields->begin();
pf != fields->end();
++pf)
{
if (pf->is_anonymous()
&& !pf->type()->deref()->is_error_type()
&& !pf->type()->deref()->is_undefined())
{
Named_type* subtype = pf->type()->named_type();
if (subtype == NULL)
subtype = pf->type()->deref()->named_type();
if (subtype == NULL)
{
// This is an error, but it will be diagnosed elsewhere.
continue;
}
if (Type::is_unexported_field_or_method(gogo, subtype, name, seen))
{
if (nt != NULL)
seen->pop_back();
return true;
}
}
}
if (nt != NULL)
seen->pop_back();
return false;
}
// Class Forward_declaration.
Forward_declaration_type::Forward_declaration_type(Named_object* named_object)
: Type(TYPE_FORWARD),
named_object_(named_object->resolve()), warned_(false)
{
go_assert(this->named_object_->is_unknown()
|| this->named_object_->is_type_declaration());
}
// Return the named object.
Named_object*
Forward_declaration_type::named_object()
{
return this->named_object_->resolve();
}
const Named_object*
Forward_declaration_type::named_object() const
{
return this->named_object_->resolve();
}
// Return the name of the forward declared type.
const std::string&
Forward_declaration_type::name() const
{
return this->named_object()->name();
}
// Warn about a use of a type which has been declared but not defined.
void
Forward_declaration_type::warn() const
{
Named_object* no = this->named_object_->resolve();
if (no->is_unknown())
{
// The name was not defined anywhere.
if (!this->warned_)
{
go_error_at(this->named_object_->location(),
"use of undefined type %qs",
no->message_name().c_str());
this->warned_ = true;
}
}
else if (no->is_type_declaration())
{
// The name was seen as a type, but the type was never defined.
if (no->type_declaration_value()->using_type())
{
go_error_at(this->named_object_->location(),
"use of undefined type %qs",
no->message_name().c_str());
this->warned_ = true;
}
}
else
{
// The name was defined, but not as a type.
if (!this->warned_)
{
go_error_at(this->named_object_->location(), "expected type");
this->warned_ = true;
}
}
}
// Get the base type of a declaration. This gives an error if the
// type has not yet been defined.
Type*
Forward_declaration_type::real_type()
{
if (this->is_defined())
{
Named_type* nt = this->named_object()->type_value();
if (!nt->is_valid())
return Type::make_error_type();
return this->named_object()->type_value();
}
else
{
this->warn();
return Type::make_error_type();
}
}
const Type*
Forward_declaration_type::real_type() const
{
if (this->is_defined())
{
const Named_type* nt = this->named_object()->type_value();
if (!nt->is_valid())
return Type::make_error_type();
return this->named_object()->type_value();
}
else
{
this->warn();
return Type::make_error_type();
}
}
// Return whether the base type is defined.
bool
Forward_declaration_type::is_defined() const
{
return this->named_object()->is_type();
}
// Add a method. This is used when methods are defined before the
// type.
Named_object*
Forward_declaration_type::add_method(const std::string& name,
Function* function)
{
Named_object* no = this->named_object();
if (no->is_unknown())
no->declare_as_type();
return no->type_declaration_value()->add_method(name, function);
}
// Add a method declaration. This is used when methods are declared
// before the type.
Named_object*
Forward_declaration_type::add_method_declaration(const std::string& name,
Package* package,
Function_type* type,
Location location)
{
Named_object* no = this->named_object();
if (no->is_unknown())
no->declare_as_type();
Type_declaration* td = no->type_declaration_value();
return td->add_method_declaration(name, package, type, location);
}
// Add an already created object as a method.
void
Forward_declaration_type::add_existing_method(Named_object* nom)
{
Named_object* no = this->named_object();
if (no->is_unknown())
no->declare_as_type();
no->type_declaration_value()->add_existing_method(nom);
}
// Traversal.
int
Forward_declaration_type::do_traverse(Traverse* traverse)
{
if (this->is_defined()
&& Type::traverse(this->real_type(), traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
return TRAVERSE_CONTINUE;
}
// Verify the type.
bool
Forward_declaration_type::do_verify()
{
if (!this->is_defined() && !this->is_nil_constant_as_type())
{
this->warn();
return false;
}
return true;
}
// Get the backend representation for the type.
Btype*
Forward_declaration_type::do_get_backend(Gogo* gogo)
{
if (this->is_defined())
return Type::get_named_base_btype(gogo, this->real_type());
if (this->warned_)
return gogo->backend()->error_type();
// We represent an undefined type as a struct with no fields. That
// should work fine for the backend, since the same case can arise
// in C.
std::vector<Backend::Btyped_identifier> fields;
Btype* bt = gogo->backend()->struct_type(fields);
return gogo->backend()->named_type(this->name(), bt,
this->named_object()->location());
}
// Build a type descriptor for a forwarded type.
Expression*
Forward_declaration_type::do_type_descriptor(Gogo* gogo, Named_type* name)
{
Location ploc = Linemap::predeclared_location();
if (!this->is_defined())
return Expression::make_error(ploc);
else
{
Type* t = this->real_type();
if (name != NULL)
return this->named_type_descriptor(gogo, t, name);
else
return Expression::make_error(this->named_object_->location());
}
}
// The reflection string.
void
Forward_declaration_type::do_reflection(Gogo* gogo, std::string* ret) const
{
this->append_reflection(this->real_type(), gogo, ret);
}
// Export a forward declaration. This can happen when a defined type
// refers to a type which is only declared (and is presumably defined
// in some other file in the same package).
void
Forward_declaration_type::do_export(Export*) const
{
// If there is a base type, that should be exported instead of this.
go_assert(!this->is_defined());
// We don't output anything.
}
// Make a forward declaration.
Type*
Type::make_forward_declaration(Named_object* named_object)
{
return new Forward_declaration_type(named_object);
}
// Class Typed_identifier_list.
// Sort the entries by name.
struct Typed_identifier_list_sort
{
public:
bool
operator()(const Typed_identifier& t1, const Typed_identifier& t2) const
{
return (Gogo::unpack_hidden_name(t1.name())
< Gogo::unpack_hidden_name(t2.name()));
}
};
void
Typed_identifier_list::sort_by_name()
{
std::sort(this->entries_.begin(), this->entries_.end(),
Typed_identifier_list_sort());
}
// Traverse types.
int
Typed_identifier_list::traverse(Traverse* traverse)
{
for (Typed_identifier_list::const_iterator p = this->begin();
p != this->end();
++p)
{
if (Type::traverse(p->type(), traverse) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
return TRAVERSE_CONTINUE;
}
// Copy the list.
Typed_identifier_list*
Typed_identifier_list::copy() const
{
Typed_identifier_list* ret = new Typed_identifier_list();
for (Typed_identifier_list::const_iterator p = this->begin();
p != this->end();
++p)
ret->push_back(Typed_identifier(p->name(), p->type(), p->location()));
return ret;
}