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// types.h -- Go frontend types. -*- C++ -*-
// 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.
#ifndef GO_TYPES_H
#define GO_TYPES_H
#include <ostream>
#include "go-linemap.h"
#include "escape.h"
class Gogo;
class Package;
class Variable;
class Traverse;
class Typed_identifier;
class Typed_identifier_list;
class Integer_type;
class Float_type;
class Complex_type;
class String_type;
class Function_type;
class Backend_function_type;
class Struct_field;
class Struct_field_list;
class Struct_type;
class Pointer_type;
class Array_type;
class Map_type;
class Channel_type;
class Interface_type;
class Named_type;
class Forward_declaration_type;
class Method;
class Methods;
class Type_hash_identical;
class Type_identical;
class Expression;
class Expression_list;
class Call_expression;
class Field_reference_expression;
class Bound_method_expression;
class Bindings;
class Named_object;
class Function;
class Translate_context;
class Export;
class Import;
class Backend_name;
class Btype;
class Bexpression;
class Bvariable;
// Type codes used in type descriptors. These must match the values
// in libgo/runtime/go-type.h. They also match the values in the gc
// compiler in src/cmd/gc/reflect.c and src/pkg/runtime/type.go,
// although this is not required.
static const int RUNTIME_TYPE_KIND_BOOL = 1;
static const int RUNTIME_TYPE_KIND_INT = 2;
static const int RUNTIME_TYPE_KIND_INT8 = 3;
static const int RUNTIME_TYPE_KIND_INT16 = 4;
static const int RUNTIME_TYPE_KIND_INT32 = 5;
static const int RUNTIME_TYPE_KIND_INT64 = 6;
static const int RUNTIME_TYPE_KIND_UINT = 7;
static const int RUNTIME_TYPE_KIND_UINT8 = 8;
static const int RUNTIME_TYPE_KIND_UINT16 = 9;
static const int RUNTIME_TYPE_KIND_UINT32 = 10;
static const int RUNTIME_TYPE_KIND_UINT64 = 11;
static const int RUNTIME_TYPE_KIND_UINTPTR = 12;
static const int RUNTIME_TYPE_KIND_FLOAT32 = 13;
static const int RUNTIME_TYPE_KIND_FLOAT64 = 14;
static const int RUNTIME_TYPE_KIND_COMPLEX64 = 15;
static const int RUNTIME_TYPE_KIND_COMPLEX128 = 16;
static const int RUNTIME_TYPE_KIND_ARRAY = 17;
static const int RUNTIME_TYPE_KIND_CHAN = 18;
static const int RUNTIME_TYPE_KIND_FUNC = 19;
static const int RUNTIME_TYPE_KIND_INTERFACE = 20;
static const int RUNTIME_TYPE_KIND_MAP = 21;
static const int RUNTIME_TYPE_KIND_PTR = 22;
static const int RUNTIME_TYPE_KIND_SLICE = 23;
static const int RUNTIME_TYPE_KIND_STRING = 24;
static const int RUNTIME_TYPE_KIND_STRUCT = 25;
static const int RUNTIME_TYPE_KIND_UNSAFE_POINTER = 26;
static const int RUNTIME_TYPE_KIND_DIRECT_IFACE = (1 << 5);
static const int RUNTIME_TYPE_KIND_GC_PROG = (1 << 6);
static const int RUNTIME_TYPE_KIND_NO_POINTERS = (1 << 7);
// To build the complete list of methods for a named type we need to
// gather all methods from anonymous fields. Those methods may
// require an arbitrary set of indirections and field offsets. There
// is also the possibility of ambiguous methods, which we could ignore
// except that we want to give a better error message for that case.
// This is a base class. There are two types of methods: named
// methods, and methods which are inherited from an anonymous field of
// interface type.
class Method
{
public:
// For methods in anonymous types we need to know the sequence of
// field references used to extract the pointer to pass to the
// method. Since each method for a particular anonymous field will
// have the sequence of field indexes, and since the indexes can be
// shared going down the chain, we use a manually managed linked
// list. The first entry in the list is the field index for the
// last field, the one passed to the method.
struct Field_indexes
{
const Field_indexes* next;
unsigned int field_index;
};
virtual ~Method()
{ }
// Get the list of field indexes.
const Field_indexes*
field_indexes() const
{ return this->field_indexes_; }
// Get the depth.
unsigned int
depth() const
{ return this->depth_; }
// Return whether this is a value method--a method which does not
// require a pointer expression.
bool
is_value_method() const
{ return this->is_value_method_; }
// Return whether we need a stub method--this is true if we can't
// just pass the main object to the method.
bool
needs_stub_method() const
{ return this->needs_stub_method_; }
// Return whether this is an ambiguous method name.
bool
is_ambiguous() const
{ return this->is_ambiguous_; }
// Note that this method is ambiguous.
void
set_is_ambiguous()
{ this->is_ambiguous_ = true; }
// Return the type of the method.
Function_type*
type() const
{ return this->do_type(); }
// Return the location of the method receiver.
Location
receiver_location() const
{ return this->do_receiver_location(); }
// Return an expression which binds this method to EXPR. This is
// something which can be used with a function call.
Expression*
bind_method(Expression* expr, Location location) const;
// Return the named object for this method. This may only be called
// after methods are finalized.
Named_object*
named_object() const;
// Get the stub object.
Named_object*
stub_object() const
{
go_assert(this->stub_ != NULL);
return this->stub_;
}
// Set the stub object.
void
set_stub_object(Named_object* no)
{
go_assert(this->stub_ == NULL);
this->stub_ = no;
}
// Get the direct interface method stub object.
Named_object*
iface_stub_object() const
{
go_assert(this->iface_stub_ != NULL);
return this->iface_stub_;
}
// Set the direct interface method stub object.
void
set_iface_stub_object(Named_object* no)
{
go_assert(this->iface_stub_ == NULL);
this->iface_stub_ = no;
}
// Return true if this method should not participate in any
// interfaces.
bool
nointerface() const
{ return this->do_nointerface(); }
protected:
// These objects are only built by the child classes.
Method(const Field_indexes* field_indexes, unsigned int depth,
bool is_value_method, bool needs_stub_method)
: field_indexes_(field_indexes), depth_(depth), stub_(NULL), iface_stub_(NULL),
is_value_method_(is_value_method), needs_stub_method_(needs_stub_method),
is_ambiguous_(false)
{ }
// The named object for this method.
virtual Named_object*
do_named_object() const = 0;
// The type of the method.
virtual Function_type*
do_type() const = 0;
// Return the location of the method receiver.
virtual Location
do_receiver_location() const = 0;
// Bind a method to an object.
virtual Expression*
do_bind_method(Expression* expr, Location location) const = 0;
// Return whether this method should not participate in interfaces.
virtual bool
do_nointerface() const = 0;
private:
// The sequence of field indexes used for this method. If this is
// NULL, then the method is defined for the current type.
const Field_indexes* field_indexes_;
// The depth at which this method was found.
unsigned int depth_;
// If a stub method is required, this is its object. This is only
// set after stub methods are built in finalize_methods.
Named_object* stub_;
// Stub object for direct interface type. This is only set after
// stub methods are built in finalize_methods.
Named_object* iface_stub_;
// Whether this is a value method--a method that does not require a
// pointer.
bool is_value_method_;
// Whether a stub method is required.
bool needs_stub_method_;
// Whether this method is ambiguous.
bool is_ambiguous_;
};
// A named method. This is what you get with a method declaration,
// either directly on the type, or inherited from some anonymous
// embedded field.
class Named_method : public Method
{
public:
Named_method(Named_object* named_object, const Field_indexes* field_indexes,
unsigned int depth, bool is_value_method,
bool needs_stub_method)
: Method(field_indexes, depth, is_value_method, needs_stub_method),
named_object_(named_object)
{ }
protected:
// Get the Named_object for the method.
Named_object*
do_named_object() const
{ return this->named_object_; }
// The type of the method.
Function_type*
do_type() const;
// Return the location of the method receiver.
Location
do_receiver_location() const;
// Bind a method to an object.
Expression*
do_bind_method(Expression* expr, Location location) const;
// Return whether this method should not participate in interfaces.
bool
do_nointerface() const;
private:
// The method itself. For a method which needs a stub, this starts
// out as the underlying method, and is later replaced with the stub
// method.
Named_object* named_object_;
};
// An interface method. This is used when an interface appears as an
// anonymous field in a named struct.
class Interface_method : public Method
{
public:
Interface_method(const std::string& name, Location location,
Function_type* fntype, const Field_indexes* field_indexes,
unsigned int depth)
: Method(field_indexes, depth, true, true),
name_(name), location_(location), fntype_(fntype)
{ }
protected:
// Get the Named_object for the method. This should never be
// called, as we always create a stub.
Named_object*
do_named_object() const
{ go_unreachable(); }
// The type of the method.
Function_type*
do_type() const
{ return this->fntype_; }
// Return the location of the method receiver.
Location
do_receiver_location() const
{ return this->location_; }
// Bind a method to an object.
Expression*
do_bind_method(Expression* expr, Location location) const;
// Return whether this method should not participate in interfaces.
bool
do_nointerface() const
{ return false; }
private:
// The name of the interface method to call.
std::string name_;
// The location of the definition of the interface method.
Location location_;
// The type of the interface method.
Function_type* fntype_;
};
// A mapping from method name to Method. This is a wrapper around a
// hash table.
class Methods
{
private:
typedef Unordered_map(std::string, Method*) Method_map;
public:
typedef Method_map::const_iterator const_iterator;
Methods()
: methods_()
{ }
// Insert a new method. Returns true if it was inserted, false if
// it was overidden or ambiguous.
bool
insert(const std::string& name, Method* m);
// The number of (unambiguous) methods.
size_t
count() const;
// Iterate.
const_iterator
begin() const
{ return this->methods_.begin(); }
const_iterator
end() const
{ return this->methods_.end(); }
// Lookup.
const_iterator
find(const std::string& name) const
{ return this->methods_.find(name); }
bool
empty() const
{ return this->methods_.empty(); }
private:
Method_map methods_;
};
// The base class for all types.
class Type
{
public:
// The types of types.
enum Type_classification
{
TYPE_ERROR,
TYPE_VOID,
TYPE_BOOLEAN,
TYPE_INTEGER,
TYPE_FLOAT,
TYPE_COMPLEX,
TYPE_STRING,
TYPE_SINK,
TYPE_FUNCTION,
TYPE_POINTER,
TYPE_NIL,
TYPE_CALL_MULTIPLE_RESULT,
TYPE_STRUCT,
TYPE_ARRAY,
TYPE_MAP,
TYPE_CHANNEL,
TYPE_INTERFACE,
TYPE_NAMED,
TYPE_FORWARD
};
virtual ~Type();
// Creators.
static Type*
make_error_type();
static Type*
make_void_type();
// Get the unnamed bool type.
static Type*
make_boolean_type();
// Get the named type "bool".
static Named_type*
lookup_bool_type();
// Make the named type "bool".
static Named_type*
make_named_bool_type();
// Make an abstract integer type.
static Integer_type*
make_abstract_integer_type();
// Make an abstract type for a character constant.
static Integer_type*
make_abstract_character_type();
// Make a named integer type with a specified size.
// RUNTIME_TYPE_KIND is the code to use in reflection information,
// to distinguish int and int32.
static Named_type*
make_integer_type(const char* name, bool is_unsigned, int bits,
int runtime_type_kind);
// Make a named integer type alias. This is used for byte and rune.
static Named_type*
make_integer_type_alias(const char* name, Named_type* real_type);
// Look up a named integer type.
static Named_type*
lookup_integer_type(const char* name);
// Make an abstract floating point type.
static Float_type*
make_abstract_float_type();
// Make a named floating point type with a specific size.
// RUNTIME_TYPE_KIND is the code to use in reflection information,
// to distinguish float and float32.
static Named_type*
make_float_type(const char* name, int bits, int runtime_type_kind);
// Look up a named float type.
static Named_type*
lookup_float_type(const char* name);
// Make an abstract complex type.
static Complex_type*
make_abstract_complex_type();
// Make a named complex type with a specific size.
// RUNTIME_TYPE_KIND is the code to use in reflection information,
// to distinguish complex and complex64.
static Named_type*
make_complex_type(const char* name, int bits, int runtime_type_kind);
// Look up a named complex type.
static Named_type*
lookup_complex_type(const char* name);
// Get the unnamed string type.
static Type*
make_string_type();
// Get the named type "string".
static Named_type*
lookup_string_type();
// Make the named type "string".
static Named_type*
make_named_string_type();
static Type*
make_sink_type();
static Function_type*
make_function_type(Typed_identifier* receiver,
Typed_identifier_list* parameters,
Typed_identifier_list* results,
Location);
static Backend_function_type*
make_backend_function_type(Typed_identifier* receiver,
Typed_identifier_list* parameters,
Typed_identifier_list* results,
Location);
static Pointer_type*
make_pointer_type(Type*);
static void
finish_pointer_types(Gogo* gogo);
static Type*
make_nil_type();
static Type*
make_call_multiple_result_type(Call_expression*);
static Struct_type*
make_struct_type(Struct_field_list* fields, Location);
static Array_type*
make_array_type(Type* element_type, Expression* length);
static Map_type*
make_map_type(Type* key_type, Type* value_type, Location);
static Channel_type*
make_channel_type(bool send, bool receive, Type*);
static Interface_type*
make_interface_type(Typed_identifier_list* methods, Location);
static Interface_type*
make_empty_interface_type(Location);
static Type*
make_type_descriptor_type();
static Type*
make_type_descriptor_ptr_type();
static Named_type*
make_named_type(Named_object*, Type*, Location);
static Type*
make_forward_declaration(Named_object*);
// Make a builtin struct type from a list of fields.
static Struct_type*
make_builtin_struct_type(int nfields, ...);
// Make a builtin named type.
static Named_type*
make_builtin_named_type(const char* name, Type* type);
// Traverse a type.
static int
traverse(Type*, Traverse*);
// Verify the type. This is called after parsing, and verifies that
// types are complete and meet the language requirements. This
// returns false if the type is invalid and we should not continue
// traversing it.
bool
verify()
{ return this->do_verify(); }
// Bit flags to pass to are_identical and friends.
// Treat error types as their own distinct type. Sometimes we
// ignore error types--treat them as identical to every other
// type--to avoid cascading errors.
static const int COMPARE_ERRORS = 1;
// Compare struct field tags when comparing structs. We ignore
// struct field tags for purposes of type conversion.
static const int COMPARE_TAGS = 2;
// Compare aliases: treat an alias to T as distinct from T.
static const int COMPARE_ALIASES = 4;
// When comparing interface types compare the interface embedding heirarchy,
// if any, rather than only comparing method sets. Useful primarily when
// exporting types.
static const int COMPARE_EMBEDDED_INTERFACES = 8;
// Return true if two types are identical. If this returns false,
// and REASON is not NULL, it may set *REASON.
static bool
are_identical(const Type* lhs, const Type* rhs, int flags,
std::string* reason);
// Return true if two types are compatible for use in a binary
// operation, other than a shift, comparison, or channel send. This
// is an equivalence relation.
static bool
are_compatible_for_binop(const Type* t1, const Type* t2);
// Return true if two types are compatible for use with the
// comparison operator. IS_EQUALITY_OP is true if this is an
// equality comparison, false if it is an ordered comparison. This
// is an equivalence relation. If this returns false, and REASON is
// not NULL, it sets *REASON.
static bool
are_compatible_for_comparison(bool is_equality_op, const Type *t1,
const Type *t2, std::string* reason);
// Return true if a type is comparable with itself. This is true of
// most types, but false for, e.g., function types.
bool
is_comparable() const
{ return Type::are_compatible_for_comparison(true, this, this, NULL); }
// Return true if a value with type RHS is assignable to a variable
// with type LHS. This is not an equivalence relation. If this
// returns false, and REASON is not NULL, it sets *REASON.
static bool
are_assignable(const Type* lhs, const Type* rhs, std::string* reason);
// Return true if a value with type RHS may be converted to type
// LHS. If this returns false, and REASON is not NULL, it sets
// *REASON.
static bool
are_convertible(const Type* lhs, const Type* rhs, std::string* reason);
// Return true if values of this type can be compared using an
// identity function which gets nothing but a pointer to the value
// and a size.
bool
compare_is_identity(Gogo* gogo)
{ return this->do_compare_is_identity(gogo); }
// Return whether values of this type are reflexive: if a comparison
// of a value with itself always returns true.
bool
is_reflexive()
{ return this->do_is_reflexive(); }
// Return whether values of this, when used as a key in map,
// requires the key to be updated when an assignment is made.
bool
needs_key_update()
{ return this->do_needs_key_update(); }
// Return whether the hash function of this type might panic. This
// is only called for types used as a key in a map type.
bool
hash_might_panic()
{ return this->do_hash_might_panic(); }
// Whether the type is permitted in the heap.
bool
in_heap() const
{ return this->do_in_heap(); }
// Return a hash code for this type for the method hash table.
// Types which are equivalent according to are_identical will have
// the same hash code.
unsigned int
hash_for_method(Gogo*, int) const;
// Return the type classification.
Type_classification
classification() const
{ return this->classification_; }
// Return the base type for this type. This looks through forward
// declarations and names. Using this with a forward declaration
// which has not been defined will return an error type.
Type*
base();
const Type*
base() const;
// Return the type skipping defined forward declarations. If this
// type is a forward declaration which has not been defined, it will
// return the Forward_declaration_type. This differs from base() in
// that it will return a Named_type, and for a
// Forward_declaration_type which is not defined it will return that
// type rather than an error type.
Type*
forwarded();
const Type*
forwarded() const;
// Return the type skipping any alias definitions and any defined
// forward declarations. This is like forwarded, but also
// recursively expands alias definitions to the aliased type.
Type*
unalias();
const Type*
unalias() const;
// Return true if this is a basic type: a type which is not composed
// of other types, and is not void.
bool
is_basic_type() const;
// Return true if this is an abstract type--an integer, floating
// point, or complex type whose size has not been determined.
bool
is_abstract() const;
// Return a non-abstract version of an abstract type.
Type*
make_non_abstract_type();
// Return true if this type is or contains a pointer. This
// determines whether the garbage collector needs to look at a value
// of this type.
bool
has_pointer() const
{ return this->do_has_pointer(); }
// Return true if this is the error type. This returns false for a
// type which is not defined, as it is called by the parser before
// all types are defined.
bool
is_error_type() const;
// Return true if this is the error type or if the type is
// undefined. If the type is undefined, this will give an error.
// This should only be called after parsing is complete.
bool
is_error() const
{ return this->base()->is_error_type(); }
// Return true if this is a void type.
bool
is_void_type() const
{ return this->classification_ == TYPE_VOID; }
// If this is an integer type, return the Integer_type. Otherwise,
// return NULL. This is a controlled dynamic_cast.
Integer_type*
integer_type()
{ return this->convert<Integer_type, TYPE_INTEGER>(); }
const Integer_type*
integer_type() const
{ return this->convert<const Integer_type, TYPE_INTEGER>(); }
// If this is a floating point type, return the Float_type.
// Otherwise, return NULL. This is a controlled dynamic_cast.
Float_type*
float_type()
{ return this->convert<Float_type, TYPE_FLOAT>(); }
const Float_type*
float_type() const
{ return this->convert<const Float_type, TYPE_FLOAT>(); }
// If this is a complex type, return the Complex_type. Otherwise,
// return NULL.
Complex_type*
complex_type()
{ return this->convert<Complex_type, TYPE_COMPLEX>(); }
const Complex_type*
complex_type() const
{ return this->convert<const Complex_type, TYPE_COMPLEX>(); }
// Return whether this is a numeric type.
bool
is_numeric_type() const
{
Type_classification tc = this->base()->classification_;
return tc == TYPE_INTEGER || tc == TYPE_FLOAT || tc == TYPE_COMPLEX;
}
// Return true if this is a boolean type.
bool
is_boolean_type() const
{ return this->base()->classification_ == TYPE_BOOLEAN; }
// Return true if this is an abstract boolean type.
bool
is_abstract_boolean_type() const
{ return this->classification_ == TYPE_BOOLEAN; }
// Return true if this is a string type.
bool
is_string_type() const
{ return this->base()->classification_ == TYPE_STRING; }
// Return true if this is an abstract string type.
bool
is_abstract_string_type() const
{ return this->classification_ == TYPE_STRING; }
// Return true if this is the sink type. This is the type of the
// blank identifier _.
bool
is_sink_type() const
{ return this->base()->classification_ == TYPE_SINK; }
// If this is a function type, return it. Otherwise, return NULL.
Function_type*
function_type()
{ return this->convert<Function_type, TYPE_FUNCTION>(); }
const Function_type*
function_type() const
{ return this->convert<const Function_type, TYPE_FUNCTION>(); }
// If this is a pointer type, return the type to which it points.
// Otherwise, return NULL.
Type*
points_to() const;
// If this is a pointer type, return the type to which it points.
// Otherwise, return the type itself.
Type*
deref()
{
Type* pt = this->points_to();
return pt != NULL ? pt : this;
}
const Type*
deref() const
{
const Type* pt = this->points_to();
return pt != NULL ? pt : this;
}
// Return true if this is the nil type. We don't use base() here,
// because this can be called during parse, and there is no way to
// name the nil type anyhow.
bool
is_nil_type() const
{ return this->classification_ == TYPE_NIL; }
// Return true if this is the predeclared constant nil being used as
// a type. This is what the parser produces for type switches which
// use "case nil".
bool
is_nil_constant_as_type() const;
// Return true if this is the return type of a function which
// returns multiple values.
bool
is_call_multiple_result_type() const
{ return this->base()->classification_ == TYPE_CALL_MULTIPLE_RESULT; }
// If this is a struct type, return it. Otherwise, return NULL.
Struct_type*
struct_type()
{ return this->convert<Struct_type, TYPE_STRUCT>(); }
const Struct_type*
struct_type() const
{ return this->convert<const Struct_type, TYPE_STRUCT>(); }
// If this is an array type, return it. Otherwise, return NULL.
Array_type*
array_type()
{ return this->convert<Array_type, TYPE_ARRAY>(); }
const Array_type*
array_type() const
{ return this->convert<const Array_type, TYPE_ARRAY>(); }
// Return whether if this is a slice type.
bool
is_slice_type() const;
// If this is a map type, return it. Otherwise, return NULL.
Map_type*
map_type()
{ return this->convert<Map_type, TYPE_MAP>(); }
const Map_type*
map_type() const
{ return this->convert<const Map_type, TYPE_MAP>(); }
// If this is a channel type, return it. Otherwise, return NULL.
Channel_type*
channel_type()
{ return this->convert<Channel_type, TYPE_CHANNEL>(); }
const Channel_type*
channel_type() const
{ return this->convert<const Channel_type, TYPE_CHANNEL>(); }
// If this is an interface type, return it. Otherwise, return NULL.
Interface_type*
interface_type()
{ return this->convert<Interface_type, TYPE_INTERFACE>(); }
const Interface_type*
interface_type() const
{ return this->convert<const Interface_type, TYPE_INTERFACE>(); }
// If this is a named type, return it. Otherwise, return NULL.
Named_type*
named_type();
const Named_type*
named_type() const;
// If this is a forward declaration, return it. Otherwise, return
// NULL.
Forward_declaration_type*
forward_declaration_type()
{ return this->convert_no_base<Forward_declaration_type, TYPE_FORWARD>(); }
const Forward_declaration_type*
forward_declaration_type() const
{
return this->convert_no_base<const Forward_declaration_type,
TYPE_FORWARD>();
}
// Return true if this type is not yet defined.
bool
is_undefined() const;
// Return true if this is the unsafe.pointer type. We currently
// represent that as pointer-to-void.
bool
is_unsafe_pointer_type() const
{ return this->points_to() != NULL && this->points_to()->is_void_type(); }
// Return whether this type is stored directly in an interface's
// data word.
bool
is_direct_iface_type() const;
// Return a version of this type with any expressions copied, but
// only if copying the expressions will affect the size of the type.
// If there are no such expressions in the type (expressions can
// only occur in array types), just return the same type. If any
// expressions can not affect the size of the type, just return the
// same type.
Type*
copy_expressions();
// Look for field or method NAME for TYPE. Return an expression for
// it, bound to EXPR.
static Expression*
bind_field_or_method(Gogo*, const Type* type, Expression* expr,
const std::string& name, Location);
// Return true if NAME is an unexported field or method of TYPE.
static bool
is_unexported_field_or_method(Gogo*, const Type*, const std::string&,
std::vector<const Named_type*>*);
// Convert the builtin named types.
static void
convert_builtin_named_types(Gogo*);
// Return the backend representation of this type.
Btype*
get_backend(Gogo*);
// Return a placeholder for the backend representation of the type.
// This will return a type of the correct size, but for which some
// of the fields may still need to be completed.
Btype*
get_backend_placeholder(Gogo*);
// Finish the backend representation of a placeholder.
void
finish_backend(Gogo*, Btype*);
// Build a type descriptor entry for this type. Return a pointer to
// it. The location is the location which causes us to need the
// entry.
Bexpression*
type_descriptor_pointer(Gogo* gogo, Location);
// Build the Garbage Collection symbol for this type. Return a pointer to it.
Bexpression*
gc_symbol_pointer(Gogo* gogo);
// Return whether this type needs a garbage collection program.
// Sets *PTRSIZE and *PTRDATA.
bool
needs_gcprog(Gogo*, int64_t* ptrsize, int64_t* ptrdata);
// Return a ptrmask variable for this type.
Bvariable*
gc_ptrmask_var(Gogo*, int64_t ptrsize, int64_t ptrdata);
// Return the type reflection string for this type.
std::string
reflection(Gogo*) const;
// Add the backend name for the type to BNAME. This will add one or
// two name components. Identical types should have the same
// backend name.
void
backend_name(Gogo*, Backend_name* bname) const;
// 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
backend_type_size(Gogo*, int64_t* psize);
// If the alignment of the type can be determined, set *PALIGN to
// the alignment in bytes and return true. Otherwise, return false.
bool
backend_type_align(Gogo*, int64_t* palign);
// If the alignment of a struct field of this type can be
// determined, set *PALIGN to the alignment in bytes and return
// true. Otherwise, return false.
bool
backend_type_field_align(Gogo*, int64_t* palign);
// Determine the ptrdata size for the backend version of this type:
// the length of the prefix of the type that can contain a pointer
// value. If it can be determined, set *PPTRDATA to the value in
// bytes and return true. Otherwise, return false.
bool
backend_type_ptrdata(Gogo*, int64_t* pptrdata);
// Determine the ptrdata size that we are going to set in the type
// descriptor. This is normally the same as backend_type_ptrdata,
// but differs if we use a gcprog for an array. The arguments and
// results are as for backend_type_ptrdata.
bool
descriptor_ptrdata(Gogo*, int64_t* pptrdata);
// Whether the backend size is known.
bool
is_backend_type_size_known(Gogo*);
// Return whether the type needs specially built type functions.
bool
needs_specific_type_functions(Gogo*);
// Get the equality function for a type. Returns NULL if the type
// is not comparable.
Named_object*
equal_function(Gogo*, Named_type* name, Function_type* equal_fntype);
// Get the hash function for a type. Returns NULL if the type is
// not comparable.
Named_object*
hash_function(Gogo*, Function_type* hash_fntype);
// Write the equal function for a type.
void
write_equal_function(Gogo*, Named_type*, int64_t size,
const Backend_name*, Function_type* equal_fntype);
// Write the hash function for a type.
void
write_hash_function(Gogo*, int64_t size, const Backend_name*,
Function_type* hash_fntype);
// Return the alignment required by the memequalN function.
static int64_t memequal_align(Gogo*, int size);
// Export the type.
void
export_type(Export* exp) const
{ this->do_export(exp); }
// Import a type.
static Type*
import_type(Import*);
protected:
Type(Type_classification);
// Functions implemented by the child class.
// Traverse the subtypes.
virtual int
do_traverse(Traverse*);
// Verify the type.
virtual bool
do_verify()
{ return true; }
virtual bool
do_has_pointer() const
{ return false; }
virtual bool
do_compare_is_identity(Gogo*) = 0;
virtual bool
do_is_reflexive()
{ return true; }
virtual bool
do_needs_key_update()
{ return false; }
virtual bool
do_hash_might_panic()
{ return false; }
virtual bool
do_in_heap() const
{ return true; }
virtual unsigned int
do_hash_for_method(Gogo*, int) const;
virtual Btype*
do_get_backend(Gogo*) = 0;
virtual Expression*
do_type_descriptor(Gogo*, Named_type* name) = 0;
virtual void
do_reflection(Gogo*, std::string*) const = 0;
virtual void
do_mangled_name(Gogo*, std::string*, bool*) const = 0;
virtual void
do_export(Export*) const;
// For children to call when they detect that they are in error.
void
set_is_error();
// Return whether a method expects a pointer as the receiver.
static bool
method_expects_pointer(const Named_object*);
// Finalize the methods for a type.
static void
finalize_methods(Gogo*, const Type*, Location, Methods**);
// Return a method from a set of methods.
static Method*
method_function(const Methods*, const std::string& name,
bool* is_ambiguous);
// A mapping from interfaces to the associated interface method
// tables for this type. This maps to a decl.
typedef Unordered_map_hash(Interface_type*, Expression*, Type_hash_identical,
Type_identical) Interface_method_tables;
// Return a pointer to the interface method table for TYPE for the
// interface INTERFACE.
static Expression*
interface_method_table(Type* type,
Interface_type *interface, bool is_pointer,
Interface_method_tables** method_tables,
Interface_method_tables** pointer_tables);
// Return a composite literal for the type descriptor entry for a
// type.
static Expression*
type_descriptor(Gogo*, Type*);
// Return a composite literal for the type descriptor entry for
// TYPE, using NAME as the name of the type.
static Expression*
named_type_descriptor(Gogo*, Type* type, Named_type* name);
// Return a composite literal for a plain type descriptor for this
// type with the given kind and name.
Expression*
plain_type_descriptor(Gogo*, int runtime_type_kind, Named_type* name);
// Build a composite literal for the basic type descriptor.
Expression*
type_descriptor_constructor(Gogo*, int runtime_type_kind, Named_type*,
const Methods*, bool only_value_methods);
// For the benefit of child class reflection string generation.
void
append_reflection(const Type* type, Gogo* gogo, std::string* ret) const
{ type->do_reflection(gogo, ret); }
// For the benefit of child class mangling.
void
append_mangled_name(const Type* type, Gogo* gogo, std::string* ret,
bool *is_non_identifier) const
{ type->do_mangled_name(gogo, ret, is_non_identifier); }
// Return the backend representation for the underlying type of a
// named type.
static Btype*
get_named_base_btype(Gogo* gogo, Type* base_type)
{ return base_type->get_btype_without_hash(gogo); }
private:
// Convert to the desired type classification, or return NULL. This
// is a controlled dynamic_cast.
template<typename Type_class, Type_classification type_classification>
Type_class*
convert()
{
Type* base = this->base();
return (base->classification_ == type_classification
? static_cast<Type_class*>(base)
: NULL);
}
template<typename Type_class, Type_classification type_classification>
const Type_class*
convert() const
{
const Type* base = this->base();
return (base->classification_ == type_classification
? static_cast<Type_class*>(base)
: NULL);
}
template<typename Type_class, Type_classification type_classification>
Type_class*
convert_no_base()
{
return (this->classification_ == type_classification
? static_cast<Type_class*>(this)
: NULL);
}
template<typename Type_class, Type_classification type_classification>
const Type_class*
convert_no_base() const
{
return (this->classification_ == type_classification
? static_cast<Type_class*>(this)
: NULL);
}
// Map unnamed types to type descriptor decls.
typedef Unordered_map_hash(const Type*, Bvariable*, Type_hash_identical,
Type_identical) Type_descriptor_vars;
static Type_descriptor_vars type_descriptor_vars;
// Build the type descriptor variable for this type.
void
make_type_descriptor_var(Gogo*);
// Map unnamed types to type descriptor decls.
typedef Unordered_map_hash(const Type*, Bvariable*, Type_hash_identical,
Type_identical) GC_symbol_vars;
static GC_symbol_vars gc_symbol_vars;
// Map ptrmask symbol names to the ptrmask variable.
typedef Unordered_map(std::string, Bvariable*) GC_gcbits_vars;
static GC_gcbits_vars gc_gcbits_vars;
// Build the GC symbol for this type.
void
make_gc_symbol_var(Gogo*);
// Return true if the type descriptor for this type should be
// defined in some other package. If NAME is not NULL, it is the
// name of this type. If this returns true it sets *PACKAGE to the
// package where the type descriptor is defined.
bool
type_descriptor_defined_elsewhere(Named_type* name, const Package** package);
// Make a composite literal for the garbage collection program for
// this type.
Expression*
gcprog_constructor(Gogo*, int64_t ptrsize, int64_t ptrdata);
// Build the hash function for a type that needs specific functions.
Named_object*
build_hash_function(Gogo*, int64_t size, Function_type* hash_fntype);
// Build the equal function for a type that needs specific functions.
Named_object*
build_equal_function(Gogo*, Named_type*, int64_t size,
Function_type* equal_fntype);
void
write_identity_hash(Gogo*, int64_t size);
void
write_identity_equal(Gogo*, int64_t size);
void
write_named_equal(Gogo*, Named_type*);
// Build a composite literal for the uncommon type information.
Expression*
uncommon_type_constructor(Gogo*, Type* uncommon_type,
Named_type*, const Methods*,
bool only_value_methods) const;
// Build a composite literal for the methods.
Expression*
methods_constructor(Gogo*, Type* methods_type, const Methods*,
bool only_value_methods) const;
// Build a composite literal for one method.
Expression*
method_constructor(Gogo*, Type* method_type, const std::string& name,
const Method*, bool only_value_methods) const;
// Add all methods for TYPE to the list of methods for THIS.
static void
add_methods_for_type(const Type* type, const Method::Field_indexes*,
unsigned int depth, bool, bool,
std::vector<const Named_type*>*,
Methods*);
static void
add_local_methods_for_type(const Named_type* type,
const Method::Field_indexes*,
unsigned int depth, bool, bool, Methods*);
static void
add_embedded_methods_for_type(const Type* type,
const Method::Field_indexes*,
unsigned int depth, bool, bool,
std::vector<const Named_type*>*,
Methods*);
static void
add_interface_methods_for_type(const Type* type,
const Method::Field_indexes*,
unsigned int depth, Methods*);
// Build stub methods for a type.
static void
build_stub_methods(Gogo*, const Type* type, const Methods* methods,
Location);
static void
build_one_stub_method(Gogo*, Method*, const char* receiver_name,
const Typed_identifier_list*, bool is_varargs,
Location);
// Build direct interface stub methods for a type.
static void
build_direct_iface_stub_methods(Gogo*, const Type*, Methods*, Location);
static void
build_one_iface_stub_method(Gogo*, Method*, const char*,
const Typed_identifier_list*,
bool, Location);
static Expression*
apply_field_indexes(Expression*, const Method::Field_indexes*,
Location);
// Look for a field or method named NAME in TYPE.
static bool
find_field_or_method(const Type* type, const std::string& name,
bool receiver_can_be_pointer,
std::vector<const Named_type*>*, int* level,
bool* is_method, bool* found_pointer_method,
std::string* ambig1, std::string* ambig2);
// Helper function for is_direct_iface_type, to prevent infinite
// recursion.
bool
is_direct_iface_type_helper(Unordered_set(const Type*)*) const;
// Get the backend representation for a type without looking in the
// hash table for identical types.
Btype*
get_btype_without_hash(Gogo*);
// A backend type that may be a placeholder.
struct Type_btype_entry
{
Btype *btype;
bool is_placeholder;
};
// A mapping from Type to Btype*, used to ensure that the backend
// representation of identical types is identical. This is only
// used for unnamed types.
typedef Unordered_map_hash(const Type*, Type_btype_entry,
Type_hash_identical, Type_identical) Type_btypes;
static Type_btypes type_btypes;
// A list of builtin named types.
static std::vector<Named_type*> named_builtin_types;
// A map from types that need a specific hash or equality function
// to the hash or equality function.
typedef Unordered_map_hash(const Type*, Named_object*, Type_hash_identical,
Type_identical) Type_function;
static Type_function type_hash_functions_table;
static Type_function type_equal_functions_table;
// Cache for reusing existing pointer types; maps from pointed-to-type
// to pointer type.
typedef Unordered_map(Type*, Pointer_type*) Pointer_type_table;
static Pointer_type_table pointer_types;
// List of placeholder pointer types.
static std::vector<Type*> placeholder_pointers;
// The type classification.
Type_classification classification_;
// The backend representation of the type, once it has been
// determined.
Btype* btype_;
// The type descriptor for this type. This starts out as NULL and
// is filled in as needed.
Bvariable* type_descriptor_var_;
// The GC symbol for this type. This starts out as NULL and
// is filled in as needed.
Bvariable* gc_symbol_var_;
};
// Type hash table operations, treating aliases as identical to the
// types that they alias.
class Type_hash_identical
{
public:
unsigned int
operator()(const Type* type) const
{
return type->hash_for_method(NULL,
Type::COMPARE_ERRORS | Type::COMPARE_TAGS);
}
};
class Type_identical
{
public:
bool
operator()(const Type* t1, const Type* t2) const
{
return Type::are_identical(t1, t2,
Type::COMPARE_ERRORS | Type::COMPARE_TAGS,
NULL);
}
};
// An identifier with a type.
class Typed_identifier
{
public:
Typed_identifier(const std::string& name, Type* type,
Location location)
: name_(name), type_(type), location_(location), note_(NULL)
{ }
// Get the name.
const std::string&
name() const
{ return this->name_; }
// Get the type.
Type*
type() const
{ return this->type_; }
// Return the location where the name was seen. This is not always
// meaningful.
Location
location() const
{ return this->location_; }
// Set the type--sometimes we see the identifier before the type.
void
set_type(Type* type)
{
go_assert(this->type_ == NULL || type->is_error_type());
this->type_ = type;
}
// Get the escape note.
std::string*
note() const
{ return this->note_; }
// Set the escape note.
void
set_note(const std::string& note)
{
if (this->note_ != NULL)
go_assert(*this->note_ == note);
else
this->note_ = new std::string(note);
}
private:
// Identifier name.
std::string name_;
// Type.
Type* type_;
// The location where the name was seen.
Location location_;
// Escape note for this typed identifier. Used when importing and exporting
// functions.
std::string* note_;
};
// A list of Typed_identifiers.
class Typed_identifier_list
{
public:
Typed_identifier_list()
: entries_()
{ }
// Whether the list is empty.
bool
empty() const
{ return this->entries_.empty(); }
// Return the number of entries in the list.
size_t
size() const
{ return this->entries_.size(); }
// Add an entry to the end of the list.
void
push_back(const Typed_identifier& td)
{ this->entries_.push_back(td); }
// Remove an entry from the end of the list.
void
pop_back()
{ this->entries_.pop_back(); }
// Set the type of entry I to TYPE.
void
set_type(size_t i, Type* type)
{
go_assert(i < this->entries_.size());
this->entries_[i].set_type(type);
}
// Sort the entries by name.
void
sort_by_name();
// Traverse types.
int
traverse(Traverse*) const;
// Return the first and last elements.
Typed_identifier&
front()
{ return this->entries_.front(); }
const Typed_identifier&
front() const
{ return this->entries_.front(); }
Typed_identifier&
back()
{ return this->entries_.back(); }
const Typed_identifier&
back() const
{ return this->entries_.back(); }
Typed_identifier&
at(size_t i)
{ return this->entries_.at(i); }
const Typed_identifier&
at(size_t i) const
{ return this->entries_.at(i); }
void
set(size_t i, const Typed_identifier& t)
{ this->entries_.at(i) = t; }
void
resize(size_t c)
{
go_assert(c <= this->entries_.size());
this->entries_.resize(c, Typed_identifier("", NULL,
Linemap::unknown_location()));
}
void
reserve(size_t c)
{ this->entries_.reserve(c); }
// Iterators.
typedef std::vector<Typed_identifier>::iterator iterator;
typedef std::vector<Typed_identifier>::const_iterator const_iterator;
iterator
begin()
{ return this->entries_.begin(); }
const_iterator
begin() const
{ return this->entries_.begin(); }
iterator
end()
{ return this->entries_.end(); }
const_iterator
end() const
{ return this->entries_.end(); }
// Return a copy of this list. This returns an independent copy of
// the vector, but does not copy the types.
Typed_identifier_list*
copy() const;
private:
std::vector<Typed_identifier> entries_;
};
// A type used to indicate a parsing error. This exists to simplify
// later error detection.
class Error_type : public Type
{
public:
Error_type()
: Type(TYPE_ERROR)
{ }
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
Btype*
do_get_backend(Gogo* gogo);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
};
// The void type.
class Void_type : public Type
{
public:
Void_type()
: Type(TYPE_VOID)
{ }
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
Btype*
do_get_backend(Gogo* gogo);
Expression*
do_type_descriptor(Gogo*, Named_type*)
{ go_unreachable(); }
void
do_reflection(Gogo*, std::string*) const
{ }
void
do_mangled_name(Gogo*, std::string*, bool*) const;
};
// The boolean type.
class Boolean_type : public Type
{
public:
Boolean_type()
: Type(TYPE_BOOLEAN)
{ }
protected:
bool
do_compare_is_identity(Gogo*)
{ return true; }
Btype*
do_get_backend(Gogo* gogo);
Expression*
do_type_descriptor(Gogo*, Named_type* name);
// We should not be asked for the reflection string of a basic type.
void
do_reflection(Gogo*, std::string* ret) const
{ ret->append("bool"); }
void
do_mangled_name(Gogo*, std::string*, bool*) const;
};
// The type of an integer.
class Integer_type : public Type
{
public:
// Create a new integer type.
static Named_type*
create_integer_type(const char* name, bool is_unsigned, int bits,
int runtime_type_kind);
// Look up an existing integer type.
static Named_type*
lookup_integer_type(const char* name);
// Create an abstract integer type.
static Integer_type*
create_abstract_integer_type();
// Create an abstract character type.
static Integer_type*
create_abstract_character_type();
// Create an alias to an integer type.
static Named_type*
create_integer_type_alias(const char* name, Named_type* real_type);
// Whether this is an abstract integer type.
bool
is_abstract() const
{ return this->is_abstract_; }
// Whether this is an unsigned type.
bool
is_unsigned() const
{ return this->is_unsigned_; }
// The number of bits.
int
bits() const
{ return this->bits_; }
// Whether this type is the same as T.
bool
is_identical(const Integer_type* t) const;
// Whether this is the type "byte" or another name for "byte".
bool
is_byte() const
{ return this->is_byte_; }
// Mark this as the "byte" type.
void
set_is_byte()
{ this->is_byte_ = true; }
// Whether this is the type "rune" or another name for "rune".
bool
is_rune() const
{ return this->is_rune_; }
// Mark this as the "rune" type.
void
set_is_rune()
{ this->is_rune_ = true; }
protected:
bool
do_compare_is_identity(Gogo*)
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
private:
Integer_type(bool is_abstract, bool is_unsigned, int bits,
int runtime_type_kind)
: Type(TYPE_INTEGER),
is_abstract_(is_abstract), is_unsigned_(is_unsigned), is_byte_(false),
is_rune_(false), bits_(bits), runtime_type_kind_(runtime_type_kind)
{ }
// Map names of integer types to the types themselves.
typedef std::map<std::string, Named_type*> Named_integer_types;
static Named_integer_types named_integer_types;
// True if this is an abstract type.
bool is_abstract_;
// True if this is an unsigned type.
bool is_unsigned_;
// True if this is the byte type.
bool is_byte_;
// True if this is the rune type.
bool is_rune_;
// The number of bits.
int bits_;
// The runtime type code used in the type descriptor for this type.
int runtime_type_kind_;
};
// The type of a floating point number.
class Float_type : public Type
{
public:
// Create a new float type.
static Named_type*
create_float_type(const char* name, int bits, int runtime_type_kind);
// Look up an existing float type.
static Named_type*
lookup_float_type(const char* name);
// Create an abstract float type.
static Float_type*
create_abstract_float_type();
// Whether this is an abstract float type.
bool
is_abstract() const
{ return this->is_abstract_; }
// The number of bits.
int
bits() const
{ return this->bits_; }
// Whether this type is the same as T.
bool
is_identical(const Float_type* t) const;
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
bool
do_is_reflexive()
{ return false; }
// Distinction between +0 and -0 requires a key update.
bool
do_needs_key_update()
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
private:
Float_type(bool is_abstract, int bits, int runtime_type_kind)
: Type(TYPE_FLOAT),
is_abstract_(is_abstract), bits_(bits),
runtime_type_kind_(runtime_type_kind)
{ }
// Map names of float types to the types themselves.
typedef std::map<std::string, Named_type*> Named_float_types;
static Named_float_types named_float_types;
// True if this is an abstract type.
bool is_abstract_;
// The number of bits in the floating point value.
int bits_;
// The runtime type code used in the type descriptor for this type.
int runtime_type_kind_;
};
// The type of a complex number.
class Complex_type : public Type
{
public:
// Create a new complex type.
static Named_type*
create_complex_type(const char* name, int bits, int runtime_type_kind);
// Look up an existing complex type.
static Named_type*
lookup_complex_type(const char* name);
// Create an abstract complex type.
static Complex_type*
create_abstract_complex_type();
// Whether this is an abstract complex type.
bool
is_abstract() const
{ return this->is_abstract_; }
// The number of bits: 64 or 128.
int bits() const
{ return this->bits_; }
// Whether this type is the same as T.
bool
is_identical(const Complex_type* t) const;
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
bool
do_is_reflexive()
{ return false; }
// Distinction between +0 and -0 requires a key update.
bool
do_needs_key_update()
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
private:
Complex_type(bool is_abstract, int bits, int runtime_type_kind)
: Type(TYPE_COMPLEX),
is_abstract_(is_abstract), bits_(bits),
runtime_type_kind_(runtime_type_kind)
{ }
// Map names of complex types to the types themselves.
typedef std::map<std::string, Named_type*> Named_complex_types;
static Named_complex_types named_complex_types;
// True if this is an abstract type.
bool is_abstract_;
// The number of bits in the complex value--64 or 128.
int bits_;
// The runtime type code used in the type descriptor for this type.
int runtime_type_kind_;
};
// The type of a string.
class String_type : public Type
{
public:
String_type()
: Type(TYPE_STRING)
{ }
protected:
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return false; }
// New string might have a smaller backing store.
bool
do_needs_key_update()
{ return true; }
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
private:
// The named string type.
static Named_type* string_type_;
};
// The type of a function.
class Function_type : public Type
{
public:
Function_type(Typed_identifier* receiver, Typed_identifier_list* parameters,
Typed_identifier_list* results, Location location)
: Type(TYPE_FUNCTION),
receiver_(receiver), parameters_(parameters), results_(results),
location_(location), is_varargs_(false), is_builtin_(false),
fnbtype_(NULL), is_tagged_(false)
{ }
// Get the receiver.
const Typed_identifier*
receiver() const
{ return this->receiver_; }
// Add an escape note for the receiver.
void
add_receiver_note(int encoding)
{ this->receiver_->set_note(Escape_note::make_tag(encoding)); }
// Get the return names and types.
const Typed_identifier_list*
results() const
{ return this->results_; }
// Get the parameter names and types.
const Typed_identifier_list*
parameters() const
{ return this->parameters_; }
// Add an escape note for the ith parameter.
void
add_parameter_note(int index, int encoding)
{ this->parameters_->at(index).set_note(Escape_note::make_tag(encoding)); }
// Whether this function has been tagged during escape analysis.
bool
is_tagged() const
{ return this->is_tagged_; }
// Mark this function as tagged after analyzing its escape.
void
set_is_tagged()
{ this->is_tagged_ = true; }
// Whether this is a varargs function.
bool
is_varargs() const
{ return this->is_varargs_; }
// Whether this is a builtin function.
bool
is_builtin() const
{ return this->is_builtin_; }
// The location where this type was defined.
Location
location() const
{ return this->location_; }
// Return whether this is a method type.
bool
is_method() const
{ return this->receiver_ != NULL; }
// Whether T is a valid redeclaration of this type. This is called
// when a function is declared more than once.
bool
is_valid_redeclaration(const Function_type* t, std::string*) const;
// Whether this type is the same as T.
bool
is_identical(const Function_type* t, bool ignore_receiver, int flags,
std::string*) const;
// Record that this is a varargs function.
void
set_is_varargs()
{ this->is_varargs_ = true; }
// Record that this is a builtin function.
void
set_is_builtin()
{ this->is_builtin_ = true; }
// Import a function type.
static Function_type*
do_import(Import*);
// Return a copy of this type without a receiver. This is only
// valid for a method type.
Function_type*
copy_without_receiver() const;
// Return a copy of this type with a receiver. This is used when an
// interface method is attached to a named or struct type.
Function_type*
copy_with_receiver(Type*) const;
// Return a copy of this type with the receiver treated as the first
// parameter. If WANT_POINTER_RECEIVER is true, the receiver is
// forced to be a pointer.
Function_type*
copy_with_receiver_as_param(bool want_pointer_receiver) const;
// Return a copy of this type ignoring any receiver and using dummy
// names for all parameters. This is used for thunks for method
// values.
Function_type*
copy_with_names() const;
static Type*
make_function_type_descriptor_type();
// Return the backend representation of this function type. This is used
// as the real type of a backend function declaration or defintion.
Btype*
get_backend_fntype(Gogo*);
// Return whether this is a Backend_function_type.
virtual bool
is_backend_function_type() const
{ return false; }
protected:
int
do_traverse(Traverse*);
// A function descriptor may be allocated on the heap.
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return false; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
Expression*
type_descriptor_params(Type*, const Typed_identifier*,
const Typed_identifier_list*);
// A mapping from a list of result types to a backend struct type.
class Results_hash
{
public:
unsigned int
operator()(const Typed_identifier_list*) const;
};
class Results_equal
{
public:
bool
operator()(const Typed_identifier_list*,
const Typed_identifier_list*) const;
};
typedef Unordered_map_hash(Typed_identifier_list*, Btype*,
Results_hash, Results_equal) Results_structs;
static Results_structs results_structs;
// The receiver name and type. This will be NULL for a normal
// function, non-NULL for a method.
Typed_identifier* receiver_;
// The parameter names and types.
Typed_identifier_list* parameters_;
// The result names and types. This will be NULL if no result was
// specified.
Typed_identifier_list* results_;
// The location where this type was defined. This exists solely to
// give a location for the fields of the struct if this function
// returns multiple values.
Location location_;
// Whether this function takes a variable number of arguments.
bool is_varargs_;
// Whether this is a special builtin function which can not simply
// be called. This is used for len, cap, etc.
bool is_builtin_;
// The backend representation of this type for backend function
// declarations and definitions.
Btype* fnbtype_;
// Whether this function has been analyzed by escape analysis. If this is
// TRUE, this function type's parameters contain a summary of the analysis.
bool is_tagged_;
};
// The type of a function's backend representation.
class Backend_function_type : public Function_type
{
public:
Backend_function_type(Typed_identifier* receiver,
Typed_identifier_list* parameters,
Typed_identifier_list* results, Location location)
: Function_type(receiver, parameters, results, location)
{ }
// Return whether this is a Backend_function_type. This overrides
// Function_type::is_backend_function_type.
bool
is_backend_function_type() const
{ return true; }
protected:
Btype*
do_get_backend(Gogo* gogo)
{ return this->get_backend_fntype(gogo); }
};
// The type of a pointer.
class Pointer_type : public Type
{
public:
Pointer_type(Type* to_type)
: Type(TYPE_POINTER),
to_type_(to_type)
{}
Type*
points_to() const
{ return this->to_type_; }
// Import a pointer type.
static Pointer_type*
do_import(Import*);
static Type*
make_pointer_type_descriptor_type();
protected:
int
do_traverse(Traverse*);
bool
do_verify()
{ return this->to_type_->verify(); }
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// The type to which this type points.
Type* to_type_;
};
// The nil type. We use a special type for nil because it is not the
// same as any other type. In C term nil has type void*, but there is
// no such type in Go.
class Nil_type : public Type
{
public:
Nil_type()
: Type(TYPE_NIL)
{ }
protected:
bool
do_compare_is_identity(Gogo*)
{ return false; }
Btype*
do_get_backend(Gogo* gogo);
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*, bool*) const;
};
// The type of a field in a struct.
class Struct_field
{
public:
explicit Struct_field(const Typed_identifier& typed_identifier)
: typed_identifier_(typed_identifier), tag_(NULL), is_imported_(false)
{ }
// The field name.
const std::string&
field_name() const;
// Return whether this struct field is named NAME.
bool
is_field_name(const std::string& name) const;
// Return whether this struct field is an unexported field named NAME.
bool
is_unexported_field_name(Gogo*, const std::string& name) const;
// Return whether this struct field is an embedded built-in type.
bool
is_embedded_builtin(Gogo*) const;
// The field type.
Type*
type() const
{ return this->typed_identifier_.type(); }
// The field location.
Location
location() const
{ return this->typed_identifier_.location(); }
// Whether the field has a tag.
bool
has_tag() const
{ return this->tag_ != NULL; }
// The tag.
const std::string&
tag() const
{
go_assert(this->tag_ != NULL);
return *this->tag_;
}
// Whether this is an anonymous field.
bool
is_anonymous() const
{ return this->typed_identifier_.name().empty(); }
// Set the tag. FIXME: This is never freed.
void
set_tag(const std::string& tag)
{ this->tag_ = new std::string(tag); }
// Record that this field is defined in an imported struct.
void
set_is_imported()
{ this->is_imported_ = true; }
// Set the type. This is only used in error cases.
void
set_type(Type* type)
{ this->typed_identifier_.set_type(type); }
private:
// The field name, type, and location.
Typed_identifier typed_identifier_;
// The field tag. This is NULL if the field has no tag.
std::string* tag_;
// Whether this field is defined in an imported struct.
bool is_imported_;
};
// A list of struct fields.
class Struct_field_list
{
public:
Struct_field_list()
: entries_()
{ }
// Whether the list is empty.
bool
empty() const
{ return this->entries_.empty(); }
// Return the number of entries.
size_t
size() const
{ return this->entries_.size(); }
// Add an entry to the end of the list.
void
push_back(const Struct_field& sf)
{ this->entries_.push_back(sf); }
// Index into the list.
const Struct_field&
at(size_t i) const
{ return this->entries_.at(i); }
// Last entry in list.
Struct_field&
back()
{ return this->entries_.back(); }
// Iterators.
typedef std::vector<Struct_field>::iterator iterator;
typedef std::vector<Struct_field>::const_iterator const_iterator;
iterator
begin()
{ return this->entries_.begin(); }
const_iterator
begin() const
{ return this->entries_.begin(); }
iterator
end()
{ return this->entries_.end(); }
const_iterator
end() const
{ return this->entries_.end(); }
private:
std::vector<Struct_field> entries_;
};
// The type of a struct.
class Struct_type : public Type
{
public:
Struct_type(Struct_field_list* fields, Location location)
: Type(TYPE_STRUCT),
fields_(fields), location_(location), all_methods_(NULL),
is_struct_incomparable_(false), has_padding_(false)
{ }
// Return the field NAME. This only looks at local fields, not at
// embedded types. If the field is found, and PINDEX is not NULL,
// this sets *PINDEX to the field index. If the field is not found,
// this returns NULL.
const Struct_field*
find_local_field(const std::string& name, unsigned int *pindex) const;
// Return the field number INDEX.
const Struct_field*
field(unsigned int index) const
{ return &this->fields_->at(index); }
// Get the struct fields.
const Struct_field_list*
fields() const
{ return this->fields_; }
// Return the number of fields.
size_t
field_count() const
{ return this->fields_->size(); }
// Location of struct definition.
Location
location() const
{ return this->location_; }
// Push a new field onto the end of the struct. This is used when
// building a closure variable.
void
push_field(const Struct_field& sf)
{ this->fields_->push_back(sf); }
// Return an expression referring to field NAME in STRUCT_EXPR, or
// NULL if there is no field with that name.
Field_reference_expression*
field_reference(Expression* struct_expr, const std::string& name,
Location) const;
// Return the total number of fields, including embedded fields.
// This is the number of values that can appear in a conversion to
// this type.
unsigned int
total_field_count() const;
// Whether this type is identical with T.
bool
is_identical(const Struct_type* t, int) const;
// Return whether NAME is a local field which is not exported. This
// is only used for better error reporting.
bool
is_unexported_local_field(Gogo*, const std::string& name) const;
// If this is an unnamed struct, build the complete list of methods,
// including those from anonymous fields, and build methods stubs if
// needed.
void
finalize_methods(Gogo*);
// Return whether this type has any methods. This should only be
// called after the finalize_methods pass.
bool
has_any_methods() const
{ return this->all_methods_ != NULL; }
// Return the methods for this type. This should only be called
// after the finalize_methods pass.
const Methods*
methods() const
{ return this->all_methods_; }
// Return the method to use for NAME. This returns NULL if there is
// no such method or if the method is ambiguous. When it returns
// NULL, this sets *IS_AMBIGUOUS if the method name is ambiguous.
Method*
method_function(const std::string& name, bool* is_ambiguous) const;
// Return a pointer to the interface method table for this type for
// the interface INTERFACE. If IS_POINTER is true, set the type
// descriptor to a pointer to this type, otherwise set it to this
// type.
Expression*
interface_method_table(Interface_type* interface, bool is_pointer);
// Traverse just the field types of a struct type.
int
traverse_field_types(Traverse* traverse)
{ return this->do_traverse(traverse); }
// 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
backend_field_offset(Gogo*, unsigned int index, int64_t* poffset);
// Finish the backend representation of all the fields.
void
finish_backend_fields(Gogo*);
// Import a struct type.
static Struct_type*
do_import(Import*);
static Type*
make_struct_type_descriptor_type();
// Return whether this is a generated struct that is not comparable.
bool
is_struct_incomparable() const
{ return this->is_struct_incomparable_; }
// Record that this is a generated struct that is not comparable.
void
set_is_struct_incomparable()
{ this->is_struct_incomparable_ = true; }
// Return whether this struct's backend type has padding, due to
// trailing zero-sized field.
bool
has_padding() const
{ return this->has_padding_; }
// Record that this struct's backend type has padding.
void
set_has_padding()
{ this->has_padding_ = true; }
// Write the hash function for this type.
void
write_hash_function(Gogo*, Function_type*);
// Write the equality function for this type.
void
write_equal_function(Gogo*, Named_type*);
// Whether we can write this type to a C header file, to implement
// -fgo-c-header.
bool
can_write_to_c_header(std::vector<const Named_object*>*,
std::vector<const Named_object*>*) const;
// Write this type to a C header file, to implement -fgo-c-header.
void
write_to_c_header(std::ostream&) const;
protected:
int
do_traverse(Traverse*);
bool
do_verify();
bool
do_has_pointer() const;
bool
do_compare_is_identity(Gogo*);
bool
do_is_reflexive();
bool
do_needs_key_update();
bool
do_hash_might_panic();
bool
do_in_heap() const;
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
bool
can_write_type_to_c_header(const Type*,
std::vector<const Named_object*>*,
std::vector<const Named_object*>*) const;
void
write_field_to_c_header(std::ostream&, const std::string&, const Type*) const;
// Used to merge method sets of identical unnamed structs.
typedef Unordered_map_hash(Struct_type*, Struct_type*, Type_hash_identical,
Type_identical) Identical_structs;
static Identical_structs identical_structs;
// Used to manage method tables for identical unnamed structs.
typedef std::pair<Interface_method_tables*, Interface_method_tables*>
Struct_method_table_pair;
typedef Unordered_map_hash(Struct_type*, Struct_method_table_pair*,
Type_hash_identical, Type_identical)
Struct_method_tables;
static Struct_method_tables struct_method_tables;
// Used to avoid infinite loops in field_reference_depth.
struct Saw_named_type
{
Saw_named_type* next;
Named_type* nt;
};
Field_reference_expression*
field_reference_depth(Expression* struct_expr, const std::string& name,
Location, Saw_named_type*,
unsigned int* depth) const;
// The fields of the struct.
Struct_field_list* fields_;
// The place where the struct was declared.
Location location_;
// If this struct is unnamed, a list of methods.
Methods* all_methods_;
// True if this is a generated struct that is not considered to be
// comparable.
bool is_struct_incomparable_;
// True if this struct's backend type has padding, due to trailing
// zero-sized field.
bool has_padding_;
};
// The type of an array.
class Array_type : public Type
{
public:
Array_type(Type* element_type, Expression* length)
: Type(TYPE_ARRAY),
element_type_(element_type), length_(length), blength_(NULL),
issued_length_error_(false), is_array_incomparable_(false)
{ }
// Return the element type.
Type*
element_type() const
{ return this->element_type_; }
// Return the length. This will return NULL for a slice.
Expression*
length() const
{ return this->length_; }
// Store the length as an int64_t into *PLEN. Return false if the
// length can not be determined. This will assert if called for a
// slice.
bool
int_length(int64_t* plen) const;
// Whether this type is identical with T.
bool
is_identical(const Array_type* t, int) const;
// Return an expression for the pointer to the values in an array.
Expression*
get_value_pointer(Gogo*, Expression* array, bool is_lvalue) const;
// Return an expression for the length of an array with this type.
Expression*
get_length(Gogo*, Expression* array) const;
// Return an expression for the capacity of an array with this type.
Expression*
get_capacity(Gogo*, Expression* array) const;
// Import an array type.
static Array_type*
do_import(Import*);
// Return the backend representation of the element type.
Btype*
get_backend_element(Gogo*, bool use_placeholder);
// Return the backend representation of the length.
Bexpression*
get_backend_length(Gogo*);
// Finish the backend representation of the element type.
void
finish_backend_element(Gogo*);
static Type*
make_array_type_descriptor_type();
static Type*
make_slice_type_descriptor_type();
// Return whether this is a generated array that is not comparable.
bool
is_array_incomparable() const
{ return this->is_array_incomparable_; }
// Record that this is a generated array that is not comparable.
void
set_is_array_incomparable()
{ this->is_array_incomparable_ = true; }
// Write the hash function for this type.
void
write_hash_function(Gogo*, Function_type*);
// Write the equality function for this type.
void
write_equal_function(Gogo*, Named_type*);
protected:
int
do_traverse(Traverse* traverse);
bool
do_verify();
bool
do_has_pointer() const;
bool
do_compare_is_identity(Gogo*);
bool
do_is_reflexive()
{
return this->length_ != NULL && this->element_type_->is_reflexive();
}
bool
do_needs_key_update()
{ return this->element_type_->needs_key_update(); }
bool
do_hash_might_panic()
{ return this->length_ != NULL && this->element_type_->hash_might_panic(); }
bool
do_in_heap() const
{ return this->length_ == NULL || this->element_type_->in_heap(); }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
bool
verify_length();
Expression*
array_type_descriptor(Gogo*, Named_type*);
Expression*
slice_type_descriptor(Gogo*, Named_type*);
// The type of elements of the array.
Type* element_type_;
// The number of elements. This may be NULL.
Expression* length_;
// The backend representation of the length.
// We only want to compute this once.
Bexpression* blength_;
// Whether or not an invalid length error has been issued for this type,
// to avoid knock-on errors.
mutable bool issued_length_error_;
// True if this is a generated array that is not considered to be
// comparable.
bool is_array_incomparable_;
};
// The type of a map.
class Map_type : public Type
{
public:
Map_type(Type* key_type, Type* val_type, Location location)
: Type(TYPE_MAP),
key_type_(key_type), val_type_(val_type), hmap_type_(NULL),
bucket_type_(NULL), hiter_type_(NULL), location_(location)
{ }
// Return the key type.
Type*
key_type() const
{ return this->key_type_; }
// Return the value type.
Type*
val_type() const
{ return this->val_type_; }
// Return the type used for an iteration over this map.
Type*
hiter_type(Gogo*);
// If this map requires the "fat" functions, returns the pointer to
// pass as the zero value to those functions. Otherwise, in the
// normal case, returns NULL.
Expression*
fat_zero_value(Gogo*);
// Map algorithm to use for this map type. We may use specialized
// fast map routines for certain key types.
enum Map_alg
{
// 32-bit key.
MAP_ALG_FAST32,
// 32-bit pointer key.
MAP_ALG_FAST32PTR,
// 64-bit key.
MAP_ALG_FAST64,
// 64-bit pointer key.
MAP_ALG_FAST64PTR,
// String key.
MAP_ALG_FASTSTR,
// Anything else.
MAP_ALG_SLOW,
};
Map_alg
algorithm(Gogo*);
// Return whether VAR is the map zero value.
static bool
is_zero_value(Variable* var);
// Return the backend representation of the map zero value.
static Bvariable*
backend_zero_value(Gogo*);
// Whether this type is identical with T.
bool
is_identical(const Map_type* t, int) const;
// Import a map type.
static Map_type*
do_import(Import*);
static Type*
make_map_type_descriptor_type();
// This must be in sync with libgo/go/runtime/map.go.
static const int bucket_size = 8;
protected:
int
do_traverse(Traverse*);
bool
do_verify();
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return false; }
bool
do_is_reflexive()
{
return this->key_type_->is_reflexive() && this->val_type_->is_reflexive();
}
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// These must be in sync with libgo/go/runtime/map.go.
static const int max_key_size = 128;
static const int max_val_size = 128;
static const int max_zero_size = 1024;
// Maps with value types larger than max_zero_size require passing a
// zero value pointer to the map functions.
// The zero value variable.
static Named_object* zero_value;
// The current size of the zero value.
static int64_t zero_value_size;
// The current alignment of the zero value.
static int64_t zero_value_align;
Type*
bucket_type(Gogo*, int64_t, int64_t);
Type*
hmap_type(Type*);
// The key type.
Type* key_type_;
// The value type.
Type* val_type_;
// The hashmap type. At run time a map is represented as a pointer
// to this type.
Type* hmap_type_;
// The bucket type, the type used to hold keys and values at run time.
Type* bucket_type_;
// The iterator type.
Type* hiter_type_;
// Where the type was defined.
Location location_;
};
// The type of a channel.
class Channel_type : public Type
{
public:
Channel_type(bool may_send, bool may_receive, Type* element_type)
: Type(TYPE_CHANNEL),
may_send_(may_send), may_receive_(may_receive),
element_type_(element_type)
{ go_assert(may_send || may_receive); }
// Whether this channel can send data.
bool
may_send() const
{ return this->may_send_; }
// Whether this channel can receive data.
bool
may_receive() const
{ return this->may_receive_; }
// The type of the values that may be sent on this channel. This is
// NULL if any type may be sent.
Type*
element_type() const
{ return this->element_type_; }
// Whether this type is identical with T.
bool
is_identical(const Channel_type* t, int) const;
// Import a channel type.
static Channel_type*
do_import(Import*);
static Type*
make_chan_type_descriptor_type();
static Type*
select_case_type();
protected:
int
do_traverse(Traverse* traverse)
{ return Type::traverse(this->element_type_, traverse); }
bool
do_verify();
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// Whether this channel can send data.
bool may_send_;
// Whether this channel can receive data.
bool may_receive_;
// The types of elements which may be sent on this channel. If this
// is NULL, it means that any type may be sent.
Type* element_type_;
};
// An interface type.
class Interface_type : public Type
{
public:
Interface_type(Typed_identifier_list* methods, Location location)
: Type(TYPE_INTERFACE),
parse_methods_(methods), all_methods_(NULL), location_(location),
package_(NULL), interface_btype_(NULL), bmethods_(NULL),
assume_identical_(NULL), methods_are_finalized_(false),
bmethods_is_placeholder_(false), seen_(false)
{ go_assert(methods == NULL || !methods->empty()); }
// The location where the interface type was defined.
Location
location() const
{ return this->location_; }
// The package where the interface type was defined. Returns NULL
// for the package currently being compiled.
Package*
package() const
{ return this->package_; }
// Return whether this is an empty interface.
bool
is_empty() const
{
go_assert(this->methods_are_finalized_);
return this->all_methods_ == NULL;
}
// Return the list of locally defined methods. This will return NULL
// for an empty interface. Embedded interfaces will appear in this
// list as an entry with no name.
const Typed_identifier_list*
local_methods() const
{ return this->parse_methods_; }
// Return the list of all methods. This will return NULL for an
// empty interface.
const Typed_identifier_list*
methods() const;
// Return the number of methods.
size_t
method_count() const;
// Return the method NAME, or NULL.
const Typed_identifier*
find_method(const std::string& name) const;
// Return the zero-based index of method NAME.
size_t
method_index(const std::string& name) const;
// Finalize the methods. This sets all_methods_. This handles
// interface inheritance.
void
finalize_methods();
// Return true if T implements this interface. If this returns
// false, and REASON is not NULL, it sets *REASON to the reason that
// it fails.
bool
implements_interface(const Type* t, std::string* reason) const;
// Whether this type is identical with T. REASON is as in
// implements_interface.
bool
is_identical(const Interface_type* t, int) const;
// Whether we can assign T to this type. is_identical is known to
// be false.
bool
is_compatible_for_assign(const Interface_type*, std::string* reason) const;
// Return whether NAME is a method which is not exported. This is
// only used for better error reporting.
bool
is_unexported_method(Gogo*, const std::string& name) const;
// Import an interface type.
static Interface_type*
do_import(Import*);
// Make a struct for an empty interface type.
static Btype*
get_backend_empty_interface_type(Gogo*);
// Get a pointer to the backend representation of the method table.
Btype*
get_backend_methods(Gogo*);
// Return a placeholder for the backend representation of the
// pointer to the method table.
Btype*
get_backend_methods_placeholder(Gogo*);
// Finish the backend representation of the method types.
void
finish_backend_methods(Gogo*);
static Type*
make_interface_type_descriptor_type();
// Return whether methods are finalized for this interface.
bool
methods_are_finalized() const
{ return this->methods_are_finalized_; }
// Sort embedded interfaces by name. Needed when we are preparing
// to emit types into the export data.
void
sort_embedded()
{
if (parse_methods_ != NULL)
parse_methods_->sort_by_name();
}
protected:
int
do_traverse(Traverse*);
bool
do_has_pointer() const
{ return true; }
bool
do_compare_is_identity(Gogo*)
{ return false; }
// Not reflexive if it contains a float.
bool
do_is_reflexive()
{ return false; }
// Distinction between +0 and -0 requires a key update if it
// contains a float.
bool
do_needs_key_update()
{ return true; }
// Hashing an unhashable type stored in an interface might panic.
bool
do_hash_might_panic()
{ return true; }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// This type guards against infinite recursion when comparing
// interface types. We keep a list of interface types assumed to be
// identical during comparison. We just keep the list on the stack.
// This permits us to compare cases like
// type I1 interface { F() interface{I1} }
// type I2 interface { F() interface{I2} }
struct Assume_identical
{
Assume_identical* next;
const Interface_type* t1;
const Interface_type* t2;
};
bool
assume_identical(const Interface_type*, const Interface_type*) const;
struct Bmethods_map_entry
{
Btype *btype;
bool is_placeholder;
};
// A mapping from Interface_type to the backend type of its bmethods_,
// used to ensure that the backend representation of identical types
// is identical.
typedef Unordered_map_hash(const Interface_type*, Bmethods_map_entry,
Type_hash_identical, Type_identical) Bmethods_map;
static Bmethods_map bmethods_map;
// The list of methods associated with the interface from the
// parser. This will be NULL for the empty interface. This may
// include unnamed interface types.
Typed_identifier_list* parse_methods_;
// The list of all methods associated with the interface. This
// expands any interface types listed in methods_. It is set by
// finalize_methods. This will be NULL for the empty interface.
Typed_identifier_list* all_methods_;
// The location where the interface was defined.
Location location_;
// The package where the interface was defined. This is NULL for
// the package being compiled.
Package* package_;
// The backend representation of this type during backend conversion.
Btype* interface_btype_;
// The backend representation of the pointer to the method table.
Btype* bmethods_;
// A list of interface types assumed to be identical during
// interface comparison.
mutable Assume_identical* assume_identical_;
// Whether the methods have been finalized.
bool methods_are_finalized_;
// Whether the bmethods_ field is a placeholder.
bool bmethods_is_placeholder_;
// Used to avoid endless recursion in do_mangled_name.
mutable bool seen_;
};
// The value we keep for a named type. This lets us get the right
// name when we convert to backend. Note that we don't actually keep
// the name here; the name is in the Named_object which points to
// this. This object exists to hold a unique backend representation for
// the type.
class Named_type : public Type
{
public:
Named_type(Named_object* named_object, Type* type, Location location)
: Type(TYPE_NAMED),
named_object_(named_object), in_function_(NULL), in_function_index_(0),
type_(type), local_methods_(NULL), all_methods_(NULL),
interface_method_tables_(NULL), pointer_interface_method_tables_(NULL),
location_(location), named_btype_(NULL), dependencies_(),
is_alias_(false), is_visible_(true), is_error_(false), in_heap_(true),
is_placeholder_(false), is_converted_(false), is_verified_(false),
seen_(false), seen_in_compare_is_identity_(false),
seen_in_get_backend_(false), seen_alias_(false)
{ }
// Return the associated Named_object. This holds the actual name.
Named_object*
named_object()
{ return this->named_object_; }
const Named_object*
named_object() const
{ return this->named_object_; }
// Set the Named_object. This is used when we see a type
// declaration followed by a type.
void
set_named_object(Named_object* no)
{ this->named_object_ = no; }
// Whether this is an alias (type T1 = T2) rather than an ordinary
// named type (type T1 T2).
bool
is_alias() const
{ return this->is_alias_; }
// Record that this type is an alias.
void
set_is_alias()
{ this->is_alias_ = true; }
// Mark this type as not permitted in the heap.
void
set_not_in_heap()
{ this->in_heap_ = false; }
// Return the function in which this type is defined. This will
// return NULL for a type defined in global scope.
const Named_object*
in_function(unsigned int *pindex) const
{
*pindex = this->in_function_index_;
return this->in_function_;
}
// Set the function in which this type is defined.
void
set_in_function(Named_object* f, unsigned int index)
{
this->in_function_ = f;
this->in_function_index_ = index;
}
// Return the name of the type.
const std::string&
name() const;
// Return the name of the type for an error message. The difference
// is that if the type is defined in a different package, this will
// return PACKAGE.NAME.
std::string
message_name() const;
// Return the underlying type.
Type*
real_type()
{ return this->type_; }
const Type*
real_type() const
{ return this->type_; }
// Return the location.
Location
location() const
{ return this->location_; }
// Whether this type is visible. This only matters when parsing.
bool
is_visible() const
{ return this->is_visible_; }
// Mark this type as visible.
void
set_is_visible()
{ this->is_visible_ = true; }
// Mark this type as invisible.
void
clear_is_visible()
{ this->is_visible_ = false; }
// Whether this is a builtin type.
bool
is_builtin() const
{ return Linemap::is_predeclared_location(this->location_); }
// Whether this named type is valid. A recursive named type is invalid.
bool
is_valid() const
{ return !this->is_error_; }
// Return the base type for this type.
Type*
named_base();
const Type*
named_base() const;
// Return whether this is an error type.
bool
is_named_error_type() const;
// Return whether this type is comparable. If REASON is not NULL,
// set *REASON when returning false.
bool
named_type_is_comparable(std::string* reason) const;
// Add a method to this type.
Named_object*
add_method(const std::string& name, Function*);
// Add a method declaration to this type.
Named_object*
add_method_declaration(const std::string& name, Package* package,
Function_type* type, Location location);
// Add an existing method--one defined before the type itself was
// defined--to a type.
void
add_existing_method(Named_object*);
// Look up a local method.
Named_object*
find_local_method(const std::string& name) const;
// Return the list of local methods.
const Bindings*
local_methods() const;
// Build the complete list of methods, including those from
// anonymous fields, and build method stubs if needed.
void
finalize_methods(Gogo*);
// Return whether this type has any methods. This should only be
// called after the finalize_methods pass.
bool
has_any_methods() const;
// Return the methods for this type. This should only be called
// after the finalized_methods pass.
const Methods*
methods() const;
// Return the method to use for NAME. This returns NULL if there is
// no such method or if the method is ambiguous. When it returns
// NULL, this sets *IS_AMBIGUOUS if the method name is ambiguous.
Method*
method_function(const std::string& name, bool *is_ambiguous) const;
// Return whether NAME is a known field or method which is not
// exported. This is only used for better error reporting.
bool
is_unexported_local_method(Gogo*, const std::string& name) const;
// Return a pointer to the interface method table for this type for
// the interface INTERFACE. If IS_POINTER is true, set the type
// descriptor to a pointer to this type, otherwise set it to this
// type.
Expression*
interface_method_table(Interface_type* interface, bool is_pointer);
// Note that a type must be converted to the backend representation
// before we convert this type.
void
add_dependency(Named_type* nt)
{ this->dependencies_.push_back(nt); }
// Return true if the size and alignment of the backend
// representation of this type is known. This is always true after
// types have been converted, but may be false beforehand.
bool
is_named_backend_type_size_known() const
{ return this->named_btype_ != NULL && !this->is_placeholder_; }
// Add to the reflection string as for Type::append_reflection, but
// if USE_ALIAS use the alias name rather than the alias target.
void
append_reflection_type_name(Gogo*, bool use_alias, std::string*) const;
// Append the symbol type name as for Type::append_mangled_name,
// but if USE_ALIAS use the alias name rather than the alias target.
void
append_symbol_type_name(Gogo*, bool use_alias, std::string*,
bool* is_non_identifier) const;
// Import a named type.
static void
import_named_type(Import*, Named_type**);
// Initial conversion to backend representation.
void
convert(Gogo*);
protected:
int
do_traverse(Traverse* traverse)
{ return Type::traverse(this->type_, traverse); }
bool
do_verify();
bool
do_has_pointer() const;
bool
do_compare_is_identity(Gogo*);
bool
do_is_reflexive();
bool
do_needs_key_update();
bool
do_in_heap() const
{ return this->in_heap_ && this->type_->in_heap(); }
unsigned int
do_hash_for_method(Gogo*, int) const;
Btype*
do_get_backend(Gogo*);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// Create the placeholder during conversion.
void
create_placeholder(Gogo*);
// A pointer back to the Named_object for this type.
Named_object* named_object_;
// If this type is defined in a function, a pointer back to the
// function in which it is defined.
Named_object* in_function_;
// The index of this type in IN_FUNCTION_.
unsigned int in_function_index_;
// The actual type.
Type* type_;
// The list of methods defined for this type. Any named type can
// have methods.
Bindings* local_methods_;
// The full list of methods for this type, including methods
// declared for anonymous fields.
Methods* all_methods_;
// A mapping from interfaces to the associated interface method
// tables for this type.
Interface_method_tables* interface_method_tables_;
// A mapping from interfaces to the associated interface method
// tables for pointers to this type.
Interface_method_tables* pointer_interface_method_tables_;
// The location where this type was defined.
Location location_;
// The backend representation of this type during backend
// conversion. This is used to avoid endless recursion when a named
// type refers to itself.
Btype* named_btype_;
// A list of types which must be converted to the backend
// representation before this type can be converted. This is for
// cases like
// type S1 { p *S2 }
// type S2 { s S1 }
// where we can't convert S2 to the backend representation unless we
// have converted S1.
std::vector<Named_type*> dependencies_;
// Whether this is an alias type.
bool is_alias_;
// Whether this type is visible. This is false if this type was
// created because it was referenced by an imported object, but the
// type itself was not exported. This will always be true for types
// created in the current package.
bool is_visible_;
// Whether this type is erroneous.
bool is_error_;
// Whether this type is permitted in the heap. This is true by
// default, false if there is a magic //go:notinheap comment.
bool in_heap_;
// Whether the current value of named_btype_ is a placeholder for
// which the final size of the type is not known.
bool is_placeholder_;
// Whether this type has been converted to the backend
// representation. Implies that is_placeholder_ is false.
bool is_converted_;
// Whether this type has been verified.
bool is_verified_;
// In a recursive operation such as has_pointer, this flag is used
// to prevent infinite recursion when a type refers to itself. This
// is mutable because it is always reset to false when the function
// exits.
mutable bool seen_;
// Like seen_, but used only by do_compare_is_identity.
bool seen_in_compare_is_identity_;
// Like seen_, but used only by do_get_backend.
bool seen_in_get_backend_;
// Like seen_, but used when resolving aliases.
mutable bool seen_alias_;
};
// A forward declaration. This handles a type which has been declared
// but not defined.
class Forward_declaration_type : public Type
{
public:
Forward_declaration_type(Named_object* named_object);
// The named object associated with this type declaration. This
// will be resolved.
Named_object*
named_object();
const Named_object*
named_object() const;
// Return the name of the type.
const std::string&
name() const;
// Return the type to which this points. Give an error if the type
// has not yet been defined.
Type*
real_type();
const Type*
real_type() const;
// Whether the base type has been defined.
bool
is_defined() const;
// Add a method to this type.
Named_object*
add_method(const std::string& name, Function*);
// Add a method declaration to this type.
Named_object*
add_method_declaration(const std::string& name, Package*, Function_type*,
Location);
// Add an already created object as a method to this type.
void
add_existing_method(Named_object*);
protected:
int
do_traverse(Traverse* traverse);
bool
do_verify();
bool
do_has_pointer() const
{ return this->real_type()->has_pointer(); }
bool
do_compare_is_identity(Gogo* gogo)
{ return this->real_type()->compare_is_identity(gogo); }
bool
do_is_reflexive()
{ return this->real_type()->is_reflexive(); }
bool
do_needs_key_update()
{ return this->real_type()->needs_key_update(); }
bool
do_in_heap() const
{ return this->real_type()->in_heap(); }
unsigned int
do_hash_for_method(Gogo* gogo, int flags) const
{ return this->real_type()->hash_for_method(gogo, flags); }
Btype*
do_get_backend(Gogo* gogo);
Expression*
do_type_descriptor(Gogo*, Named_type*);
void
do_reflection(Gogo*, std::string*) const;
void
do_mangled_name(Gogo*, std::string*, bool*) const;
void
do_export(Export*) const;
private:
// Issue a warning about a use of an undefined type.
void
warn() const;
// The type declaration.
Named_object* named_object_;
// Whether we have issued a warning about this type.
mutable bool warned_;
};
// The Type_context struct describes what we expect for the type of an
// expression.
struct Type_context
{
// The exact type we expect, if known. This may be NULL.
Type* type;
// Whether an abstract type is permitted.
bool may_be_abstract;
// Constructors.
Type_context()
: type(NULL), may_be_abstract(false)
{ }
Type_context(Type* a_type, bool a_may_be_abstract)
: type(a_type), may_be_abstract(a_may_be_abstract)
{ }
};
#endif // !defined(GO_TYPES_H)