blob: 5654e30849d3bde6b321d16437d5df91e88465a1 [file] [log] [blame]
// gogo.cc -- Go frontend parsed representation.
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "go-system.h"
#include <fstream>
#include "filenames.h"
#include "go-c.h"
#include "go-diagnostics.h"
#include "go-encode-id.h"
#include "go-dump.h"
#include "go-optimize.h"
#include "lex.h"
#include "types.h"
#include "statements.h"
#include "expressions.h"
#include "runtime.h"
#include "import.h"
#include "export.h"
#include "backend.h"
#include "gogo.h"
// Class Gogo.
Gogo::Gogo(Backend* backend, Linemap* linemap, int, int pointer_size)
: backend_(backend),
linemap_(linemap),
package_(NULL),
functions_(),
globals_(new Bindings(NULL)),
file_block_names_(),
imports_(),
imported_unsafe_(false),
current_file_imported_unsafe_(false),
packages_(),
init_functions_(),
var_deps_(),
need_init_fn_(false),
init_fn_name_(),
imported_init_fns_(),
pkgpath_(),
pkgpath_symbol_(),
prefix_(),
pkgpath_set_(false),
pkgpath_from_option_(false),
prefix_from_option_(false),
relative_import_path_(),
c_header_(),
check_divide_by_zero_(true),
check_divide_overflow_(true),
compiling_runtime_(false),
debug_escape_level_(0),
nil_check_size_threshold_(4096),
verify_types_(),
interface_types_(),
specific_type_functions_(),
specific_type_functions_are_written_(false),
named_types_are_converted_(false),
analysis_sets_(),
gc_roots_(),
imported_inlinable_functions_(),
imported_inline_functions_()
{
const Location loc = Linemap::predeclared_location();
Named_type* uint8_type = Type::make_integer_type("uint8", true, 8,
RUNTIME_TYPE_KIND_UINT8);
this->add_named_type(uint8_type);
this->add_named_type(Type::make_integer_type("uint16", true, 16,
RUNTIME_TYPE_KIND_UINT16));
this->add_named_type(Type::make_integer_type("uint32", true, 32,
RUNTIME_TYPE_KIND_UINT32));
this->add_named_type(Type::make_integer_type("uint64", true, 64,
RUNTIME_TYPE_KIND_UINT64));
this->add_named_type(Type::make_integer_type("int8", false, 8,
RUNTIME_TYPE_KIND_INT8));
this->add_named_type(Type::make_integer_type("int16", false, 16,
RUNTIME_TYPE_KIND_INT16));
Named_type* int32_type = Type::make_integer_type("int32", false, 32,
RUNTIME_TYPE_KIND_INT32);
this->add_named_type(int32_type);
this->add_named_type(Type::make_integer_type("int64", false, 64,
RUNTIME_TYPE_KIND_INT64));
this->add_named_type(Type::make_float_type("float32", 32,
RUNTIME_TYPE_KIND_FLOAT32));
this->add_named_type(Type::make_float_type("float64", 64,
RUNTIME_TYPE_KIND_FLOAT64));
this->add_named_type(Type::make_complex_type("complex64", 64,
RUNTIME_TYPE_KIND_COMPLEX64));
this->add_named_type(Type::make_complex_type("complex128", 128,
RUNTIME_TYPE_KIND_COMPLEX128));
int int_type_size = pointer_size;
if (int_type_size < 32)
int_type_size = 32;
this->add_named_type(Type::make_integer_type("uint", true,
int_type_size,
RUNTIME_TYPE_KIND_UINT));
Named_type* int_type = Type::make_integer_type("int", false, int_type_size,
RUNTIME_TYPE_KIND_INT);
this->add_named_type(int_type);
this->add_named_type(Type::make_integer_type("uintptr", true,
pointer_size,
RUNTIME_TYPE_KIND_UINTPTR));
// "byte" is an alias for "uint8".
uint8_type->integer_type()->set_is_byte();
Named_object* byte_type = Named_object::make_type("byte", NULL, uint8_type,
loc);
byte_type->type_value()->set_is_alias();
this->add_named_type(byte_type->type_value());
// "rune" is an alias for "int32".
int32_type->integer_type()->set_is_rune();
Named_object* rune_type = Named_object::make_type("rune", NULL, int32_type,
loc);
rune_type->type_value()->set_is_alias();
this->add_named_type(rune_type->type_value());
this->add_named_type(Type::make_named_bool_type());
this->add_named_type(Type::make_named_string_type());
// "error" is interface { Error() string }.
{
Typed_identifier_list *methods = new Typed_identifier_list;
Typed_identifier_list *results = new Typed_identifier_list;
results->push_back(Typed_identifier("", Type::lookup_string_type(), loc));
Type *method_type = Type::make_function_type(NULL, NULL, results, loc);
methods->push_back(Typed_identifier("Error", method_type, loc));
Interface_type *error_iface = Type::make_interface_type(methods, loc);
error_iface->finalize_methods();
Named_type *error_type = Named_object::make_type("error", NULL, error_iface, loc)->type_value();
this->add_named_type(error_type);
}
this->globals_->add_constant(Typed_identifier("true",
Type::make_boolean_type(),
loc),
NULL,
Expression::make_boolean(true, loc),
0);
this->globals_->add_constant(Typed_identifier("false",
Type::make_boolean_type(),
loc),
NULL,
Expression::make_boolean(false, loc),
0);
this->globals_->add_constant(Typed_identifier("nil", Type::make_nil_type(),
loc),
NULL,
Expression::make_nil(loc),
0);
Type* abstract_int_type = Type::make_abstract_integer_type();
this->globals_->add_constant(Typed_identifier("iota", abstract_int_type,
loc),
NULL,
Expression::make_iota(),
0);
Function_type* new_type = Type::make_function_type(NULL, NULL, NULL, loc);
new_type->set_is_varargs();
new_type->set_is_builtin();
this->globals_->add_function_declaration("new", NULL, new_type, loc);
Function_type* make_type = Type::make_function_type(NULL, NULL, NULL, loc);
make_type->set_is_varargs();
make_type->set_is_builtin();
this->globals_->add_function_declaration("make", NULL, make_type, loc);
Typed_identifier_list* len_result = new Typed_identifier_list();
len_result->push_back(Typed_identifier("", int_type, loc));
Function_type* len_type = Type::make_function_type(NULL, NULL, len_result,
loc);
len_type->set_is_builtin();
this->globals_->add_function_declaration("len", NULL, len_type, loc);
Typed_identifier_list* cap_result = new Typed_identifier_list();
cap_result->push_back(Typed_identifier("", int_type, loc));
Function_type* cap_type = Type::make_function_type(NULL, NULL, len_result,
loc);
cap_type->set_is_builtin();
this->globals_->add_function_declaration("cap", NULL, cap_type, loc);
Function_type* print_type = Type::make_function_type(NULL, NULL, NULL, loc);
print_type->set_is_varargs();
print_type->set_is_builtin();
this->globals_->add_function_declaration("print", NULL, print_type, loc);
print_type = Type::make_function_type(NULL, NULL, NULL, loc);
print_type->set_is_varargs();
print_type->set_is_builtin();
this->globals_->add_function_declaration("println", NULL, print_type, loc);
Type *empty = Type::make_empty_interface_type(loc);
Typed_identifier_list* panic_parms = new Typed_identifier_list();
panic_parms->push_back(Typed_identifier("e", empty, loc));
Function_type *panic_type = Type::make_function_type(NULL, panic_parms,
NULL, loc);
panic_type->set_is_builtin();
this->globals_->add_function_declaration("panic", NULL, panic_type, loc);
Typed_identifier_list* recover_result = new Typed_identifier_list();
recover_result->push_back(Typed_identifier("", empty, loc));
Function_type* recover_type = Type::make_function_type(NULL, NULL,
recover_result,
loc);
recover_type->set_is_builtin();
this->globals_->add_function_declaration("recover", NULL, recover_type, loc);
Function_type* close_type = Type::make_function_type(NULL, NULL, NULL, loc);
close_type->set_is_varargs();
close_type->set_is_builtin();
this->globals_->add_function_declaration("close", NULL, close_type, loc);
Typed_identifier_list* copy_result = new Typed_identifier_list();
copy_result->push_back(Typed_identifier("", int_type, loc));
Function_type* copy_type = Type::make_function_type(NULL, NULL,
copy_result, loc);
copy_type->set_is_varargs();
copy_type->set_is_builtin();
this->globals_->add_function_declaration("copy", NULL, copy_type, loc);
Function_type* append_type = Type::make_function_type(NULL, NULL, NULL, loc);
append_type->set_is_varargs();
append_type->set_is_builtin();
this->globals_->add_function_declaration("append", NULL, append_type, loc);
Function_type* complex_type = Type::make_function_type(NULL, NULL, NULL, loc);
complex_type->set_is_varargs();
complex_type->set_is_builtin();
this->globals_->add_function_declaration("complex", NULL, complex_type, loc);
Function_type* real_type = Type::make_function_type(NULL, NULL, NULL, loc);
real_type->set_is_varargs();
real_type->set_is_builtin();
this->globals_->add_function_declaration("real", NULL, real_type, loc);
Function_type* imag_type = Type::make_function_type(NULL, NULL, NULL, loc);
imag_type->set_is_varargs();
imag_type->set_is_builtin();
this->globals_->add_function_declaration("imag", NULL, imag_type, loc);
Function_type* delete_type = Type::make_function_type(NULL, NULL, NULL, loc);
delete_type->set_is_varargs();
delete_type->set_is_builtin();
this->globals_->add_function_declaration("delete", NULL, delete_type, loc);
}
std::string
Gogo::pkgpath_for_symbol(const std::string& pkgpath)
{
go_assert(!pkgpath.empty());
return go_encode_id(pkgpath);
}
// Get the package path to use for type reflection data. This should
// ideally be unique across the entire link.
const std::string&
Gogo::pkgpath() const
{
go_assert(this->pkgpath_set_);
return this->pkgpath_;
}
// Set the package path from the -fgo-pkgpath command line option.
void
Gogo::set_pkgpath(const std::string& arg)
{
go_assert(!this->pkgpath_set_);
this->pkgpath_ = arg;
this->pkgpath_set_ = true;
this->pkgpath_from_option_ = true;
}
// Get the package path to use for symbol names.
const std::string&
Gogo::pkgpath_symbol() const
{
go_assert(this->pkgpath_set_);
return this->pkgpath_symbol_;
}
// Set the unique prefix to use to determine the package path, from
// the -fgo-prefix command line option.
void
Gogo::set_prefix(const std::string& arg)
{
go_assert(!this->prefix_from_option_);
this->prefix_ = arg;
this->prefix_from_option_ = true;
}
// Given a name which may or may not have been hidden, append the
// appropriate version of the name to the result string. Take care
// to avoid creating a sequence that will be rejected by go_encode_id
// (avoid ..u, ..U, ..z).
void
Gogo::append_possibly_hidden_name(std::string *result, const std::string& name)
{
// FIXME: This adds in pkgpath twice for hidden symbols, which is
// less than ideal.
if (!Gogo::is_hidden_name(name))
(*result) += name;
else
{
std::string n = ".";
std::string pkgpath = Gogo::hidden_name_pkgpath(name);
char lastR = result->at(result->length() - 1);
char firstP = pkgpath.at(0);
if (lastR == '.' && (firstP == 'u' || firstP == 'U' || firstP == 'z'))
n = "_.";
n.append(pkgpath);
n.append(1, '.');
n.append(Gogo::unpack_hidden_name(name));
(*result) += n;
}
}
// Munge name for use in an error message.
std::string
Gogo::message_name(const std::string& name)
{
return go_localize_identifier(Gogo::unpack_hidden_name(name).c_str());
}
// Get the package name.
const std::string&
Gogo::package_name() const
{
go_assert(this->package_ != NULL);
return this->package_->package_name();
}
// Set the package name.
void
Gogo::set_package_name(const std::string& package_name,
Location location)
{
if (this->package_ != NULL)
{
if (this->package_->package_name() != package_name)
go_error_at(location, "expected package %<%s%>",
Gogo::message_name(this->package_->package_name()).c_str());
return;
}
// Now that we know the name of the package we are compiling, set
// the package path to use for reflect.Type.PkgPath and global
// symbol names.
if (this->pkgpath_set_)
this->pkgpath_symbol_ = Gogo::pkgpath_for_symbol(this->pkgpath_);
else
{
if (!this->prefix_from_option_ && package_name == "main")
{
this->pkgpath_ = package_name;
this->pkgpath_symbol_ = Gogo::pkgpath_for_symbol(package_name);
}
else
{
if (!this->prefix_from_option_)
this->prefix_ = "go";
this->pkgpath_ = this->prefix_ + '.' + package_name;
this->pkgpath_symbol_ = (Gogo::pkgpath_for_symbol(this->prefix_) + '.'
+ Gogo::pkgpath_for_symbol(package_name));
}
this->pkgpath_set_ = true;
}
this->package_ = this->register_package(this->pkgpath_,
this->pkgpath_symbol_, location);
this->package_->set_package_name(package_name, location);
if (this->is_main_package())
{
// Declare "main" as a function which takes no parameters and
// returns no value.
Location uloc = Linemap::unknown_location();
this->declare_function(Gogo::pack_hidden_name("main", false),
Type::make_function_type (NULL, NULL, NULL, uloc),
uloc);
}
}
// Return whether this is the "main" package. This is not true if
// -fgo-pkgpath or -fgo-prefix was used.
bool
Gogo::is_main_package() const
{
return (this->package_name() == "main"
&& !this->pkgpath_from_option_
&& !this->prefix_from_option_);
}
// Import a package.
void
Gogo::import_package(const std::string& filename,
const std::string& local_name,
bool is_local_name_exported,
bool must_exist,
Location location)
{
if (filename.empty())
{
go_error_at(location, "import path is empty");
return;
}
const char *pf = filename.data();
const char *pend = pf + filename.length();
while (pf < pend)
{
unsigned int c;
int adv = Lex::fetch_char(pf, &c);
if (adv == 0)
{
go_error_at(location, "import path contains invalid UTF-8 sequence");
return;
}
if (c == '\0')
{
go_error_at(location, "import path contains NUL");
return;
}
if (c < 0x20 || c == 0x7f)
{
go_error_at(location, "import path contains control character");
return;
}
if (c == '\\')
{
go_error_at(location, "import path contains backslash; use slash");
return;
}
if (Lex::is_unicode_space(c))
{
go_error_at(location, "import path contains space character");
return;
}
if (c < 0x7f && strchr("!\"#$%&'()*,:;<=>?[]^`{|}", c) != NULL)
{
go_error_at(location,
"import path contains invalid character '%c'", c);
return;
}
pf += adv;
}
if (IS_ABSOLUTE_PATH(filename.c_str()))
{
go_error_at(location, "import path cannot be absolute path");
return;
}
if (local_name == "init")
go_error_at(location, "cannot import package as init");
if (filename == "unsafe")
{
this->import_unsafe(local_name, is_local_name_exported, location);
this->current_file_imported_unsafe_ = true;
return;
}
Imports::const_iterator p = this->imports_.find(filename);
if (p != this->imports_.end())
{
Package* package = p->second;
package->set_location(location);
std::string ln = local_name;
bool is_ln_exported = is_local_name_exported;
if (ln.empty())
{
ln = package->package_name();
go_assert(!ln.empty());
is_ln_exported = Lex::is_exported_name(ln);
}
if (ln == "_")
;
else if (ln == ".")
{
Bindings* bindings = package->bindings();
for (Bindings::const_declarations_iterator p =
bindings->begin_declarations();
p != bindings->end_declarations();
++p)
this->add_dot_import_object(p->second);
std::string dot_alias = "." + package->package_name();
package->add_alias(dot_alias, location);
}
else
{
package->add_alias(ln, location);
ln = this->pack_hidden_name(ln, is_ln_exported);
this->package_->bindings()->add_package(ln, package);
}
return;
}
Import::Stream* stream = Import::open_package(filename, location,
this->relative_import_path_);
if (stream == NULL)
{
if (must_exist)
go_error_at(location, "import file %qs not found", filename.c_str());
return;
}
Import* imp = new Import(stream, location);
imp->register_builtin_types(this);
Package* package = imp->import(this, local_name, is_local_name_exported);
if (package != NULL)
{
if (package->pkgpath() == this->pkgpath())
go_error_at(location,
("imported package uses same package path as package "
"being compiled (see -fgo-pkgpath option)"));
this->imports_.insert(std::make_pair(filename, package));
}
imp->clear_stream();
delete stream;
// FIXME: we never delete imp; we may need it for inlinable functions.
}
Import_init *
Gogo::lookup_init(const std::string& init_name)
{
Import_init tmp("", init_name, -1);
Import_init_set::iterator it = this->imported_init_fns_.find(&tmp);
return (it != this->imported_init_fns_.end()) ? *it : NULL;
}
// Add an import control function for an imported package to the list.
void
Gogo::add_import_init_fn(const std::string& package_name,
const std::string& init_name, int prio)
{
for (Import_init_set::iterator p =
this->imported_init_fns_.begin();
p != this->imported_init_fns_.end();
++p)
{
Import_init *ii = (*p);
if (ii->init_name() == init_name)
{
// If a test of package P1, built as part of package P1,
// imports package P2, and P2 imports P1 (perhaps
// indirectly), then we will see the same import name with
// different import priorities. That is OK, so don't give
// an error about it.
if (ii->package_name() != package_name)
{
go_error_at(Linemap::unknown_location(),
"duplicate package initialization name %qs",
Gogo::message_name(init_name).c_str());
go_inform(Linemap::unknown_location(), "used by package %qs",
Gogo::message_name(ii->package_name()).c_str());
go_inform(Linemap::unknown_location(), " and by package %qs",
Gogo::message_name(package_name).c_str());
}
ii->set_priority(prio);
return;
}
}
Import_init* nii = new Import_init(package_name, init_name, prio);
this->imported_init_fns_.insert(nii);
}
// Return whether we are at the global binding level.
bool
Gogo::in_global_scope() const
{
return this->functions_.empty();
}
// Return the current binding contour.
Bindings*
Gogo::current_bindings()
{
if (!this->functions_.empty())
return this->functions_.back().blocks.back()->bindings();
else if (this->package_ != NULL)
return this->package_->bindings();
else
return this->globals_;
}
const Bindings*
Gogo::current_bindings() const
{
if (!this->functions_.empty())
return this->functions_.back().blocks.back()->bindings();
else if (this->package_ != NULL)
return this->package_->bindings();
else
return this->globals_;
}
void
Gogo::update_init_priority(Import_init* ii,
std::set<const Import_init *>* visited)
{
visited->insert(ii);
int succ_prior = -1;
for (std::set<std::string>::const_iterator pci =
ii->precursors().begin();
pci != ii->precursors().end();
++pci)
{
Import_init* succ = this->lookup_init(*pci);
if (visited->find(succ) == visited->end())
update_init_priority(succ, visited);
succ_prior = std::max(succ_prior, succ->priority());
}
if (ii->priority() <= succ_prior)
ii->set_priority(succ_prior + 1);
}
void
Gogo::recompute_init_priorities()
{
std::set<Import_init *> nonroots;
for (Import_init_set::const_iterator p =
this->imported_init_fns_.begin();
p != this->imported_init_fns_.end();
++p)
{
const Import_init *ii = *p;
for (std::set<std::string>::const_iterator pci =
ii->precursors().begin();
pci != ii->precursors().end();
++pci)
{
Import_init* ii = this->lookup_init(*pci);
nonroots.insert(ii);
}
}
// Recursively update priorities starting at roots.
std::set<const Import_init*> visited;
for (Import_init_set::iterator p =
this->imported_init_fns_.begin();
p != this->imported_init_fns_.end();
++p)
{
Import_init* ii = *p;
if (nonroots.find(ii) != nonroots.end())
continue;
update_init_priority(ii, &visited);
}
}
// Add statements to INIT_STMTS which run the initialization
// functions for imported packages. This is only used for the "main"
// package.
void
Gogo::init_imports(std::vector<Bstatement*>& init_stmts, Bfunction *bfunction)
{
go_assert(this->is_main_package());
if (this->imported_init_fns_.empty())
return;
Location unknown_loc = Linemap::unknown_location();
Function_type* func_type =
Type::make_function_type(NULL, NULL, NULL, unknown_loc);
Btype* fntype = func_type->get_backend_fntype(this);
// Recompute init priorities based on a walk of the init graph.
recompute_init_priorities();
// We must call them in increasing priority order.
std::vector<const Import_init*> v;
for (Import_init_set::const_iterator p =
this->imported_init_fns_.begin();
p != this->imported_init_fns_.end();
++p)
{
if ((*p)->priority() < 0)
go_error_at(Linemap::unknown_location(),
"internal error: failed to set init priority for %s",
(*p)->package_name().c_str());
v.push_back(*p);
}
std::sort(v.begin(), v.end(), priority_compare);
// We build calls to the init functions, which take no arguments.
std::vector<Bexpression*> empty_args;
for (std::vector<const Import_init*>::const_iterator p = v.begin();
p != v.end();
++p)
{
const Import_init* ii = *p;
std::string user_name = ii->package_name() + ".init";
const std::string& init_name(ii->init_name());
const unsigned int flags =
(Backend::function_is_visible
| Backend::function_is_declaration
| Backend::function_is_inlinable);
Bfunction* pfunc = this->backend()->function(fntype, user_name, init_name,
flags, unknown_loc);
Bexpression* pfunc_code =
this->backend()->function_code_expression(pfunc, unknown_loc);
Bexpression* pfunc_call =
this->backend()->call_expression(bfunction, pfunc_code, empty_args,
NULL, unknown_loc);
init_stmts.push_back(this->backend()->expression_statement(bfunction,
pfunc_call));
}
}
// Register global variables with the garbage collector. We need to
// register all variables which can hold a pointer value. They become
// roots during the mark phase. We build a struct that is easy to
// hook into a list of roots.
// type gcRoot struct {
// decl unsafe.Pointer // Pointer to variable.
// size uintptr // Total size of variable.
// ptrdata uintptr // Length of variable's gcdata.
// gcdata *byte // Pointer mask.
// }
//
// type gcRootList struct {
// next *gcRootList
// count int
// roots [...]gcRoot
// }
// The last entry in the roots array has a NULL decl field.
void
Gogo::register_gc_vars(const std::vector<Named_object*>& var_gc,
std::vector<Bstatement*>& init_stmts,
Bfunction* init_bfn)
{
if (var_gc.empty() && this->gc_roots_.empty())
return;
Type* pvt = Type::make_pointer_type(Type::make_void_type());
Type* uintptr_type = Type::lookup_integer_type("uintptr");
Type* byte_type = this->lookup_global("byte")->type_value();
Type* pointer_byte_type = Type::make_pointer_type(byte_type);
Struct_type* root_type =
Type::make_builtin_struct_type(4,
"decl", pvt,
"size", uintptr_type,
"ptrdata", uintptr_type,
"gcdata", pointer_byte_type);
Location builtin_loc = Linemap::predeclared_location();
unsigned long roots_len = var_gc.size() + this->gc_roots_.size();
Expression* length = Expression::make_integer_ul(roots_len, NULL,
builtin_loc);
Array_type* root_array_type = Type::make_array_type(root_type, length);
root_array_type->set_is_array_incomparable();
Type* int_type = Type::lookup_integer_type("int");
Struct_type* root_list_type =
Type::make_builtin_struct_type(3,
"next", pvt,
"count", int_type,
"roots", root_array_type);
// Build an initializer for the roots array.
Expression_list* roots_init = new Expression_list();
for (std::vector<Named_object*>::const_iterator p = var_gc.begin();
p != var_gc.end();
++p)
{
Expression_list* init = new Expression_list();
Location no_loc = (*p)->location();
Expression* decl = Expression::make_var_reference(*p, no_loc);
Expression* decl_addr =
Expression::make_unary(OPERATOR_AND, decl, no_loc);
decl_addr->unary_expression()->set_does_not_escape();
decl_addr = Expression::make_cast(pvt, decl_addr, no_loc);
init->push_back(decl_addr);
Expression* size =
Expression::make_type_info(decl->type(),
Expression::TYPE_INFO_SIZE);
init->push_back(size);
Expression* ptrdata =
Expression::make_type_info(decl->type(),
Expression::TYPE_INFO_BACKEND_PTRDATA);
init->push_back(ptrdata);
Expression* gcdata = Expression::make_ptrmask_symbol(decl->type());
init->push_back(gcdata);
Expression* root_ctor =
Expression::make_struct_composite_literal(root_type, init, no_loc);
roots_init->push_back(root_ctor);
}
for (std::vector<Expression*>::const_iterator p = this->gc_roots_.begin();
p != this->gc_roots_.end();
++p)
{
Expression_list *init = new Expression_list();
Expression* expr = *p;
Location eloc = expr->location();
init->push_back(Expression::make_cast(pvt, expr, eloc));
Type* type = expr->type()->points_to();
go_assert(type != NULL);
Expression* size =
Expression::make_type_info(type,
Expression::TYPE_INFO_SIZE);
init->push_back(size);
Expression* ptrdata =
Expression::make_type_info(type,
Expression::TYPE_INFO_BACKEND_PTRDATA);
init->push_back(ptrdata);
Expression* gcdata = Expression::make_ptrmask_symbol(type);
init->push_back(gcdata);
Expression* root_ctor =
Expression::make_struct_composite_literal(root_type, init, eloc);
roots_init->push_back(root_ctor);
}
// Build a constructor for the struct.
Expression_list* root_list_init = new Expression_list();
root_list_init->push_back(Expression::make_nil(builtin_loc));
root_list_init->push_back(Expression::make_integer_ul(roots_len, int_type,
builtin_loc));
Expression* roots_ctor =
Expression::make_array_composite_literal(root_array_type, roots_init,
builtin_loc);
root_list_init->push_back(roots_ctor);
Expression* root_list_ctor =
Expression::make_struct_composite_literal(root_list_type, root_list_init,
builtin_loc);
Expression* root_addr = Expression::make_unary(OPERATOR_AND, root_list_ctor,
builtin_loc);
root_addr->unary_expression()->set_is_gc_root();
Expression* register_roots = Runtime::make_call(Runtime::REGISTER_GC_ROOTS,
builtin_loc, 1, root_addr);
Translate_context context(this, NULL, NULL, NULL);
Bexpression* bcall = register_roots->get_backend(&context);
init_stmts.push_back(this->backend()->expression_statement(init_bfn, bcall));
}
// Build the decl for the initialization function.
Named_object*
Gogo::initialization_function_decl()
{
std::string name = this->get_init_fn_name();
Location loc = this->package_->location();
Function_type* fntype = Type::make_function_type(NULL, NULL, NULL, loc);
Function* initfn = new Function(fntype, NULL, NULL, loc);
return Named_object::make_function(name, NULL, initfn);
}
// Create the magic initialization function. CODE_STMT is the
// code that it needs to run.
Named_object*
Gogo::create_initialization_function(Named_object* initfn,
Bstatement* code_stmt)
{
// Make sure that we thought we needed an initialization function,
// as otherwise we will not have reported it in the export data.
go_assert(this->is_main_package() || this->need_init_fn_);
if (initfn == NULL)
initfn = this->initialization_function_decl();
// Bind the initialization function code to a block.
Bfunction* fndecl = initfn->func_value()->get_or_make_decl(this, initfn);
Location pkg_loc = this->package_->location();
std::vector<Bvariable*> vars;
this->backend()->block(fndecl, NULL, vars, pkg_loc, pkg_loc);
if (!this->backend()->function_set_body(fndecl, code_stmt))
{
go_assert(saw_errors());
return NULL;
}
return initfn;
}
// Given an expression, collect all the global variables defined in
// this package that it references.
class Find_vars : public Traverse
{
private:
// The list of variables we accumulate.
typedef Unordered_set(Named_object*) Vars;
// A hash table we use to avoid looping. The index is a
// Named_object* or a Temporary_statement*. We only look through
// objects defined in this package.
typedef Unordered_set(const void*) Seen_objects;
public:
Find_vars()
: Traverse(traverse_expressions),
vars_(), seen_objects_()
{ }
// An iterator through the variables found, after the traversal.
typedef Vars::const_iterator const_iterator;
const_iterator
begin() const
{ return this->vars_.begin(); }
const_iterator
end() const
{ return this->vars_.end(); }
int
expression(Expression**);
private:
// Accumulated variables.
Vars vars_;
// Objects we have already seen.
Seen_objects seen_objects_;
};
// Collect global variables referenced by EXPR. Look through function
// calls and variable initializations.
int
Find_vars::expression(Expression** pexpr)
{
Expression* e = *pexpr;
Var_expression* ve = e->var_expression();
if (ve != NULL)
{
Named_object* v = ve->named_object();
if (!v->is_variable() || v->package() != NULL)
{
// This is a result parameter or a variable defined in a
// different package. Either way we don't care about it.
return TRAVERSE_CONTINUE;
}
std::pair<Seen_objects::iterator, bool> ins =
this->seen_objects_.insert(v);
if (!ins.second)
{
// We've seen this variable before.
return TRAVERSE_CONTINUE;
}
if (v->var_value()->is_global())
this->vars_.insert(v);
Expression* init = v->var_value()->init();
if (init != NULL)
{
if (Expression::traverse(&init, this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
// We traverse the code of any function or bound method we see. Note that
// this means that we will traverse the code of a function or bound method
// whose address is taken even if it is not called.
Func_expression* fe = e->func_expression();
Bound_method_expression* bme = e->bound_method_expression();
if (fe != NULL || bme != NULL)
{
const Named_object* f = fe != NULL ? fe->named_object() : bme->function();
if (f->is_function() && f->package() == NULL)
{
std::pair<Seen_objects::iterator, bool> ins =
this->seen_objects_.insert(f);
if (ins.second)
{
// This is the first time we have seen this name.
if (f->func_value()->block()->traverse(this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
}
Temporary_reference_expression* tre = e->temporary_reference_expression();
if (tre != NULL)
{
Temporary_statement* ts = tre->statement();
Expression* init = ts->init();
if (init != NULL)
{
std::pair<Seen_objects::iterator, bool> ins =
this->seen_objects_.insert(ts);
if (ins.second)
{
// This is the first time we have seen this temporary
// statement.
if (Expression::traverse(&init, this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
}
return TRAVERSE_CONTINUE;
}
// Return true if EXPR, PREINIT, or DEP refers to VAR.
static bool
expression_requires(Expression* expr, Block* preinit, Named_object* dep,
Named_object* var)
{
Find_vars find_vars;
if (expr != NULL)
Expression::traverse(&expr, &find_vars);
if (preinit != NULL)
preinit->traverse(&find_vars);
if (dep != NULL)
{
Expression* init = dep->var_value()->init();
if (init != NULL)
Expression::traverse(&init, &find_vars);
if (dep->var_value()->has_pre_init())
dep->var_value()->preinit()->traverse(&find_vars);
}
for (Find_vars::const_iterator p = find_vars.begin();
p != find_vars.end();
++p)
{
if (*p == var)
return true;
}
return false;
}
// Sort variable initializations. If the initialization expression
// for variable A refers directly or indirectly to the initialization
// expression for variable B, then we must initialize B before A.
class Var_init
{
public:
Var_init()
: var_(NULL), init_(NULL), refs_(NULL), dep_count_(0)
{ }
Var_init(Named_object* var, Bstatement* init)
: var_(var), init_(init), refs_(NULL), dep_count_(0)
{ }
// Return the variable.
Named_object*
var() const
{ return this->var_; }
// Return the initialization expression.
Bstatement*
init() const
{ return this->init_; }
// Add a reference.
void
add_ref(Named_object* var);
// The variables which this variable's initializers refer to.
const std::vector<Named_object*>*
refs()
{ return this->refs_; }
// Clear the references, if any.
void
clear_refs();
// Return the number of remaining dependencies.
size_t
dep_count() const
{ return this->dep_count_; }
// Increment the number of dependencies.
void
add_dependency()
{ ++this->dep_count_; }
// Decrement the number of dependencies.
void
remove_dependency()
{ --this->dep_count_; }
private:
// The variable being initialized.
Named_object* var_;
// The backend initialization statement.
Bstatement* init_;
// Variables this refers to.
std::vector<Named_object*>* refs_;
// The number of initializations this is dependent on. A variable
// initialization should not be emitted if any of its dependencies
// have not yet been resolved.
size_t dep_count_;
};
// Add a reference.
void
Var_init::add_ref(Named_object* var)
{
if (this->refs_ == NULL)
this->refs_ = new std::vector<Named_object*>;
this->refs_->push_back(var);
}
// Clear the references, if any.
void
Var_init::clear_refs()
{
if (this->refs_ != NULL)
{
delete this->refs_;
this->refs_ = NULL;
}
}
// For comparing Var_init keys in a map.
inline bool
operator<(const Var_init& v1, const Var_init& v2)
{ return v1.var()->name() < v2.var()->name(); }
typedef std::list<Var_init> Var_inits;
// Sort the variable initializations. The rule we follow is that we
// emit them in the order they appear in the array, except that if the
// initialization expression for a variable V1 depends upon another
// variable V2 then we initialize V1 after V2.
static void
sort_var_inits(Gogo* gogo, Var_inits* var_inits)
{
if (var_inits->empty())
return;
std::map<Named_object*, Var_init*> var_to_init;
// A mapping from a variable initialization to a set of
// variable initializations that depend on it.
typedef std::map<Var_init, std::set<Var_init*> > Init_deps;
Init_deps init_deps;
bool init_loop = false;
// Compute all variable references.
for (Var_inits::iterator pvar = var_inits->begin();
pvar != var_inits->end();
++pvar)
{
Named_object* var = pvar->var();
var_to_init[var] = &*pvar;
Find_vars find_vars;
Expression* init = var->var_value()->init();
if (init != NULL)
Expression::traverse(&init, &find_vars);
if (var->var_value()->has_pre_init())
var->var_value()->preinit()->traverse(&find_vars);
Named_object* dep = gogo->var_depends_on(var->var_value());
if (dep != NULL)
{
Expression* dinit = dep->var_value()->init();
if (dinit != NULL)
Expression::traverse(&dinit, &find_vars);
if (dep->var_value()->has_pre_init())
dep->var_value()->preinit()->traverse(&find_vars);
}
for (Find_vars::const_iterator p = find_vars.begin();
p != find_vars.end();
++p)
pvar->add_ref(*p);
}
// Add dependencies to init_deps, and check for cycles.
for (Var_inits::iterator pvar = var_inits->begin();
pvar != var_inits->end();
++pvar)
{
Named_object* var = pvar->var();
const std::vector<Named_object*>* refs = pvar->refs();
if (refs == NULL)
continue;
for (std::vector<Named_object*>::const_iterator pdep = refs->begin();
pdep != refs->end();
++pdep)
{
Named_object* dep = *pdep;
if (var == dep)
{
// This is a reference from a variable to itself, which
// may indicate a loop. We only report an error if
// there is an initializer and there is no dependency.
// When there is no initializer, it means that the
// preinitializer sets the variable, which will appear
// to be a loop here.
if (var->var_value()->init() != NULL
&& gogo->var_depends_on(var->var_value()) == NULL)
go_error_at(var->location(),
("initialization expression for %qs "
"depends upon itself"),
var->message_name().c_str());
continue;
}
Var_init* dep_init = var_to_init[dep];
if (dep_init == NULL)
{
// This is a dependency on some variable that doesn't
// have an initializer, so for purposes of
// initialization ordering this is irrelevant.
continue;
}
init_deps[*dep_init].insert(&(*pvar));
pvar->add_dependency();
// Check for cycles.
const std::vector<Named_object*>* deprefs = dep_init->refs();
if (deprefs == NULL)
continue;
for (std::vector<Named_object*>::const_iterator pdepdep =
deprefs->begin();
pdepdep != deprefs->end();
++pdepdep)
{
if (*pdepdep == var)
{
go_error_at(var->location(),
("initialization expressions for %qs and "
"%qs depend upon each other"),
var->message_name().c_str(),
dep->message_name().c_str());
go_inform(dep->location(), "%qs defined here",
dep->message_name().c_str());
init_loop = true;
break;
}
}
}
}
var_to_init.clear();
for (Var_inits::iterator pvar = var_inits->begin();
pvar != var_inits->end();
++pvar)
pvar->clear_refs();
// If there are no dependencies then the declaration order is sorted.
if (!init_deps.empty() && !init_loop)
{
// Otherwise, sort variable initializations by emitting all variables with
// no dependencies in declaration order. VAR_INITS is already in
// declaration order.
Var_inits ready;
while (!var_inits->empty())
{
Var_inits::iterator v1;;
for (v1 = var_inits->begin(); v1 != var_inits->end(); ++v1)
{
if (v1->dep_count() == 0)
break;
}
go_assert(v1 != var_inits->end());
// V1 either has no dependencies or its dependencies have already
// been emitted, add it to READY next. When V1 is emitted, remove
// a dependency from each V that depends on V1.
ready.splice(ready.end(), *var_inits, v1);
Init_deps::iterator p1 = init_deps.find(*v1);
if (p1 != init_deps.end())
{
std::set<Var_init*> resolved = p1->second;
for (std::set<Var_init*>::iterator pv = resolved.begin();
pv != resolved.end();
++pv)
(*pv)->remove_dependency();
init_deps.erase(p1);
}
}
var_inits->swap(ready);
go_assert(init_deps.empty());
}
}
// Give an error if the initialization expression for VAR depends on
// itself. We only check if INIT is not NULL and there is no
// dependency; when INIT is NULL, it means that PREINIT sets VAR,
// which we will interpret as a loop.
void
Gogo::check_self_dep(Named_object* var)
{
Expression* init = var->var_value()->init();
Block* preinit = var->var_value()->preinit();
Named_object* dep = this->var_depends_on(var->var_value());
if (init != NULL
&& dep == NULL
&& expression_requires(init, preinit, NULL, var))
go_error_at(var->location(),
"initialization expression for %qs depends upon itself",
var->message_name().c_str());
}
// Write out the global definitions.
void
Gogo::write_globals()
{
this->build_interface_method_tables();
Bindings* bindings = this->current_bindings();
for (Bindings::const_declarations_iterator p = bindings->begin_declarations();
p != bindings->end_declarations();
++p)
{
// If any function declarations needed a descriptor, make sure
// we build it.
Named_object* no = p->second;
if (no->is_function_declaration())
no->func_declaration_value()->build_backend_descriptor(this);
}
// Lists of globally declared types, variables, constants, and functions
// that must be defined.
std::vector<Btype*> type_decls;
std::vector<Bvariable*> var_decls;
std::vector<Bexpression*> const_decls;
std::vector<Bfunction*> func_decls;
// The init function declaration and associated Bfunction, if necessary.
Named_object* init_fndecl = NULL;
Bfunction* init_bfn = NULL;
std::vector<Bstatement*> init_stmts;
std::vector<Bstatement*> var_init_stmts;
if (this->is_main_package())
{
init_fndecl = this->initialization_function_decl();
init_bfn = init_fndecl->func_value()->get_or_make_decl(this, init_fndecl);
this->init_imports(init_stmts, init_bfn);
}
// A list of variable initializations.
Var_inits var_inits;
// A list of variables which need to be registered with the garbage
// collector.
size_t count_definitions = bindings->size_definitions();
std::vector<Named_object*> var_gc;
var_gc.reserve(count_definitions);
for (Bindings::const_definitions_iterator p = bindings->begin_definitions();
p != bindings->end_definitions();
++p)
{
Named_object* no = *p;
go_assert(!no->is_type_declaration() && !no->is_function_declaration());
// There is nothing to do for a package.
if (no->is_package())
continue;
// There is nothing to do for an object which was imported from
// a different package into the global scope.
if (no->package() != NULL)
continue;
// Skip blank named functions and constants.
if ((no->is_function() && no->func_value()->is_sink())
|| (no->is_const() && no->const_value()->is_sink()))
continue;
// There is nothing useful we can output for constants which
// have ideal or non-integral type.
if (no->is_const())
{
Type* type = no->const_value()->type();
if (type == NULL)
type = no->const_value()->expr()->type();
if (type->is_abstract() || !type->is_numeric_type())
continue;
}
if (!no->is_variable())
no->get_backend(this, const_decls, type_decls, func_decls);
else
{
Variable* var = no->var_value();
Bvariable* bvar = no->get_backend_variable(this, NULL);
var_decls.push_back(bvar);
// Check for a sink variable, which may be used to run an
// initializer purely for its side effects.
bool is_sink = no->name()[0] == '_' && no->name()[1] == '.';
Bstatement* var_init_stmt = NULL;
if (!var->has_pre_init())
{
// If the backend representation of the variable initializer is
// constant, we can just set the initial value using
// global_var_set_init instead of during the init() function.
// The initializer is constant if it is the zero-value of the
// variable's type or if the initial value is an immutable value
// that is not copied to the heap.
bool is_static_initializer = false;
if (var->init() == NULL)
is_static_initializer = true;
else
{
Type* var_type = var->type();
Expression* init = var->init();
Expression* init_cast =
Expression::make_cast(var_type, init, var->location());
is_static_initializer = init_cast->is_static_initializer();
}
// Non-constant variable initializations might need to create
// temporary variables, which will need the initialization
// function as context.
Named_object* var_init_fn;
if (is_static_initializer)
var_init_fn = NULL;
else
{
if (init_fndecl == NULL)
{
init_fndecl = this->initialization_function_decl();
Function* func = init_fndecl->func_value();
init_bfn = func->get_or_make_decl(this, init_fndecl);
}
var_init_fn = init_fndecl;
}
Bexpression* var_binit = var->get_init(this, var_init_fn);
if (var_binit == NULL)
;
else if (is_static_initializer)
{
if (expression_requires(var->init(), NULL,
this->var_depends_on(var), no))
go_error_at(no->location(),
"initialization expression for %qs depends "
"upon itself",
no->message_name().c_str());
this->backend()->global_variable_set_init(bvar, var_binit);
}
else if (is_sink)
var_init_stmt =
this->backend()->expression_statement(init_bfn, var_binit);
else
{
Location loc = var->location();
Bexpression* var_expr =
this->backend()->var_expression(bvar, loc);
var_init_stmt =
this->backend()->assignment_statement(init_bfn, var_expr,
var_binit, loc);
}
}
else
{
// We are going to create temporary variables which
// means that we need an fndecl.
if (init_fndecl == NULL)
init_fndecl = this->initialization_function_decl();
Bvariable* var_decl = is_sink ? NULL : bvar;
var_init_stmt = var->get_init_block(this, init_fndecl, var_decl);
}
if (var_init_stmt != NULL)
{
if (var->init() == NULL && !var->has_pre_init())
var_init_stmts.push_back(var_init_stmt);
else
var_inits.push_back(Var_init(no, var_init_stmt));
}
else if (this->var_depends_on(var) != NULL)
{
// This variable is initialized from something that is
// not in its init or preinit. This variable needs to
// participate in dependency analysis sorting, in case
// some other variable depends on this one.
Btype* btype = no->var_value()->type()->get_backend(this);
Bexpression* zero = this->backend()->zero_expression(btype);
Bstatement* zero_stmt =
this->backend()->expression_statement(init_bfn, zero);
var_inits.push_back(Var_init(no, zero_stmt));
}
// Collect a list of all global variables with pointers,
// to register them for the garbage collector.
if (!is_sink && var->type()->has_pointer())
{
// Avoid putting runtime.gcRoots itself on the list.
if (this->compiling_runtime()
&& this->package_name() == "runtime"
&& (Gogo::unpack_hidden_name(no->name()) == "gcRoots"
|| Gogo::unpack_hidden_name(no->name()) == "gcRootsIndex"))
;
else
var_gc.push_back(no);
}
}
}
// Output inline functions, which are in different packages.
for (std::vector<Named_object*>::const_iterator p =
this->imported_inline_functions_.begin();
p != this->imported_inline_functions_.end();
++p)
(*p)->get_backend(this, const_decls, type_decls, func_decls);
// Register global variables with the garbage collector.
this->register_gc_vars(var_gc, init_stmts, init_bfn);
// Simple variable initializations, after all variables are
// registered.
init_stmts.push_back(this->backend()->statement_list(var_init_stmts));
// Complete variable initializations, first sorting them into a
// workable order.
if (!var_inits.empty())
{
sort_var_inits(this, &var_inits);
for (Var_inits::const_iterator p = var_inits.begin();
p != var_inits.end();
++p)
init_stmts.push_back(p->init());
}
// After all the variables are initialized, call the init
// functions if there are any. Init functions take no arguments, so
// we pass in EMPTY_ARGS to call them.
std::vector<Bexpression*> empty_args;
for (std::vector<Named_object*>::const_iterator p =
this->init_functions_.begin();
p != this->init_functions_.end();
++p)
{
Location func_loc = (*p)->location();
Function* func = (*p)->func_value();
Bfunction* initfn = func->get_or_make_decl(this, *p);
Bexpression* func_code =
this->backend()->function_code_expression(initfn, func_loc);
Bexpression* call = this->backend()->call_expression(init_bfn, func_code,
empty_args,
NULL, func_loc);
Bstatement* ist = this->backend()->expression_statement(init_bfn, call);
init_stmts.push_back(ist);
}
// Set up a magic function to do all the initialization actions.
// This will be called if this package is imported.
Bstatement* init_fncode = this->backend()->statement_list(init_stmts);
if (this->need_init_fn_ || this->is_main_package())
{
init_fndecl =
this->create_initialization_function(init_fndecl, init_fncode);
if (init_fndecl != NULL)
func_decls.push_back(init_fndecl->func_value()->get_decl());
}
// We should not have seen any new bindings created during the conversion.
go_assert(count_definitions == this->current_bindings()->size_definitions());
// Define all globally declared values.
if (!saw_errors())
this->backend()->write_global_definitions(type_decls, const_decls,
func_decls, var_decls);
}
// Return the current block.
Block*
Gogo::current_block()
{
if (this->functions_.empty())
return NULL;
else
return this->functions_.back().blocks.back();
}
// Look up a name in the current binding contour. If PFUNCTION is not
// NULL, set it to the function in which the name is defined, or NULL
// if the name is defined in global scope.
Named_object*
Gogo::lookup(const std::string& name, Named_object** pfunction) const
{
if (pfunction != NULL)
*pfunction = NULL;
if (Gogo::is_sink_name(name))
return Named_object::make_sink();
for (Open_functions::const_reverse_iterator p = this->functions_.rbegin();
p != this->functions_.rend();
++p)
{
Named_object* ret = p->blocks.back()->bindings()->lookup(name);
if (ret != NULL)
{
if (pfunction != NULL)
*pfunction = p->function;
return ret;
}
}
if (this->package_ != NULL)
{
Named_object* ret = this->package_->bindings()->lookup(name);
if (ret != NULL)
{
if (ret->package() != NULL)
{
std::string dot_alias = "." + ret->package()->package_name();
ret->package()->note_usage(dot_alias);
}
return ret;
}
}
// We do not look in the global namespace. If we did, the global
// namespace would effectively hide names which were defined in
// package scope which we have not yet seen. Instead,
// define_global_names is called after parsing is over to connect
// undefined names at package scope with names defined at global
// scope.
return NULL;
}
// Look up a name in the current block, without searching enclosing
// blocks.
Named_object*
Gogo::lookup_in_block(const std::string& name) const
{
go_assert(!this->functions_.empty());
go_assert(!this->functions_.back().blocks.empty());
return this->functions_.back().blocks.back()->bindings()->lookup_local(name);
}
// Look up a name in the global namespace.
Named_object*
Gogo::lookup_global(const char* name) const
{
return this->globals_->lookup(name);
}
// Add an imported package.
Package*
Gogo::add_imported_package(const std::string& real_name,
const std::string& alias_arg,
bool is_alias_exported,
const std::string& pkgpath,
const std::string& pkgpath_symbol,
Location location,
bool* padd_to_globals)
{
Package* ret = this->register_package(pkgpath, pkgpath_symbol, location);
ret->set_package_name(real_name, location);
*padd_to_globals = false;
if (alias_arg == "_")
;
else if (alias_arg == ".")
{
*padd_to_globals = true;
std::string dot_alias = "." + real_name;
ret->add_alias(dot_alias, location);
}
else
{
std::string alias = alias_arg;
if (alias.empty())
{
alias = real_name;
is_alias_exported = Lex::is_exported_name(alias);
}
ret->add_alias(alias, location);
alias = this->pack_hidden_name(alias, is_alias_exported);
Named_object* no = this->package_->bindings()->add_package(alias, ret);
if (!no->is_package())
return NULL;
}
return ret;
}
// Register a package. This package may or may not be imported. This
// returns the Package structure for the package, creating if it
// necessary. LOCATION is the location of the import statement that
// led us to see this package. PKGPATH_SYMBOL is the symbol to use
// for names in the package; it may be the empty string, in which case
// we either get it later or make a guess when we need it.
Package*
Gogo::register_package(const std::string& pkgpath,
const std::string& pkgpath_symbol, Location location)
{
Package* package = NULL;
std::pair<Packages::iterator, bool> ins =
this->packages_.insert(std::make_pair(pkgpath, package));
if (!ins.second)
{
// We have seen this package name before.
package = ins.first->second;
go_assert(package != NULL && package->pkgpath() == pkgpath);
if (!pkgpath_symbol.empty())
package->set_pkgpath_symbol(pkgpath_symbol);
if (Linemap::is_unknown_location(package->location()))
package->set_location(location);
}
else
{
// First time we have seen this package name.
package = new Package(pkgpath, pkgpath_symbol, location);
go_assert(ins.first->second == NULL);
ins.first->second = package;
}
return package;
}
// Return the pkgpath symbol for a package, given the pkgpath.
std::string
Gogo::pkgpath_symbol_for_package(const std::string& pkgpath)
{
Packages::iterator p = this->packages_.find(pkgpath);
go_assert(p != this->packages_.end());
return p->second->pkgpath_symbol();
}
// Start compiling a function.
Named_object*
Gogo::start_function(const std::string& name, Function_type* type,
bool add_method_to_type, Location location)
{
bool at_top_level = this->functions_.empty();
Block* block = new Block(NULL, location);
Named_object* enclosing = (at_top_level
? NULL
: this->functions_.back().function);
Function* function = new Function(type, enclosing, block, location);
if (type->is_method())
{
const Typed_identifier* receiver = type->receiver();
Variable* this_param = new Variable(receiver->type(), NULL, false,
true, true, location);
std::string rname = receiver->name();
if (rname.empty() || Gogo::is_sink_name(rname))
{
// We need to give receivers a name since they wind up in
// DECL_ARGUMENTS. FIXME.
static unsigned int count;
char buf[50];
snprintf(buf, sizeof buf, "r.%u", count);
++count;
rname = buf;
}
block->bindings()->add_variable(rname, NULL, this_param);
}
const Typed_identifier_list* parameters = type->parameters();
bool is_varargs = type->is_varargs();
if (parameters != NULL)
{
for (Typed_identifier_list::const_iterator p = parameters->begin();
p != parameters->end();
++p)
{
Variable* param = new Variable(p->type(), NULL, false, true, false,
p->location());
if (is_varargs && p + 1 == parameters->end())
param->set_is_varargs_parameter();
std::string pname = p->name();
if (pname.empty() || Gogo::is_sink_name(pname))
{
// We need to give parameters a name since they wind up
// in DECL_ARGUMENTS. FIXME.
static unsigned int count;
char buf[50];
snprintf(buf, sizeof buf, "p.%u", count);
++count;
pname = buf;
}
block->bindings()->add_variable(pname, NULL, param);
}
}
function->create_result_variables(this);
const std::string* pname;
std::string nested_name;
bool is_init = false;
if (Gogo::unpack_hidden_name(name) == "init" && !type->is_method())
{
if ((type->parameters() != NULL && !type->parameters()->empty())
|| (type->results() != NULL && !type->results()->empty()))
go_error_at(location,
"func init must have no arguments and no return values");
// There can be multiple "init" functions, so give them each a
// different name.
nested_name = this->init_function_name();
pname = &nested_name;
is_init = true;
}
else if (!name.empty())
pname = &name;
else
{
// Invent a name for a nested function.
nested_name = this->nested_function_name(enclosing);
pname = &nested_name;
}
Named_object* ret;
if (Gogo::is_sink_name(*pname))
{
std::string sname(this->sink_function_name());
ret = Named_object::make_function(sname, NULL, function);
ret->func_value()->set_is_sink();
if (!type->is_method())
ret = this->package_->bindings()->add_named_object(ret);
else if (add_method_to_type)
{
// We should report errors even for sink methods.
Type* rtype = type->receiver()->type();
// Avoid points_to and deref to avoid getting an error if
// the type is not yet defined.
if (rtype->classification() == Type::TYPE_POINTER)
rtype = rtype->points_to();
while (rtype->named_type() != NULL
&& rtype->named_type()->is_alias())
rtype = rtype->named_type()->real_type()->forwarded();
if (rtype->is_error_type())
;
else if (rtype->named_type() != NULL)
{
if (rtype->named_type()->named_object()->package() != NULL)
go_error_at(type->receiver()->location(),
"may not define methods on non-local type");
}
else if (rtype->forward_declaration_type() != NULL)
{
// Go ahead and add the method in case we need to report
// an error when we see the definition.
rtype->forward_declaration_type()->add_existing_method(ret);
}
else
go_error_at(type->receiver()->location(),
("invalid receiver type "
"(receiver must be a named type)"));
}
}
else if (!type->is_method())
{
ret = this->package_->bindings()->add_function(*pname, NULL, function);
if (!ret->is_function() || ret->func_value() != function)
{
// Redefinition error. Invent a name to avoid knockon
// errors.
std::string rname(this->redefined_function_name());
ret = this->package_->bindings()->add_function(rname, NULL, function);
}
}
else
{
if (!add_method_to_type)
ret = Named_object::make_function(name, NULL, function);
else
{
go_assert(at_top_level);
Type* rtype = type->receiver()->type();
// We want to look through the pointer created by the
// parser, without getting an error if the type is not yet
// defined.
if (rtype->classification() == Type::TYPE_POINTER)
rtype = rtype->points_to();
while (rtype->named_type() != NULL
&& rtype->named_type()->is_alias())
rtype = rtype->named_type()->real_type()->forwarded();
if (rtype->is_error_type())
ret = Named_object::make_function(name, NULL, function);
else if (rtype->named_type() != NULL)
{
if (rtype->named_type()->named_object()->package() != NULL)
{
go_error_at(type->receiver()->location(),
"may not define methods on non-local type");
ret = Named_object::make_function(name, NULL, function);
}
else
{
ret = rtype->named_type()->add_method(name, function);
if (!ret->is_function())
{
// Redefinition error.
ret = Named_object::make_function(name, NULL, function);
}
}
}
else if (rtype->forward_declaration_type() != NULL)
{
Named_object* type_no =
rtype->forward_declaration_type()->named_object();
if (type_no->is_unknown())
{
// If we are seeing methods it really must be a
// type. Declare it as such. An alternative would
// be to support lists of methods for unknown
// expressions. Either way the error messages if
// this is not a type are going to get confusing.
Named_object* declared =
this->declare_package_type(type_no->name(),
type_no->location());
go_assert(declared
== type_no->unknown_value()->real_named_object());
}
ret = rtype->forward_declaration_type()->add_method(name,
function);
}
else
{
go_error_at(type->receiver()->location(),
("invalid receiver type (receiver must "
"be a named type)"));
ret = Named_object::make_function(name, NULL, function);
}
}
this->package_->bindings()->add_method(ret);
}
this->functions_.resize(this->functions_.size() + 1);
Open_function& of(this->functions_.back());
of.function = ret;
of.blocks.push_back(block);
if (is_init)
{
this->init_functions_.push_back(ret);
this->need_init_fn_ = true;
}
return ret;
}
// Finish compiling a function.
void
Gogo::finish_function(Location location)
{
this->finish_block(location);
go_assert(this->functions_.back().blocks.empty());
this->functions_.pop_back();
}
// Return the current function.
Named_object*
Gogo::current_function() const
{
go_assert(!this->functions_.empty());
return this->functions_.back().function;
}
// Start a new block.
void
Gogo::start_block(Location location)
{
go_assert(!this->functions_.empty());
Block* block = new Block(this->current_block(), location);
this->functions_.back().blocks.push_back(block);
}
// Finish a block.
Block*
Gogo::finish_block(Location location)
{
go_assert(!this->functions_.empty());
go_assert(!this->functions_.back().blocks.empty());
Block* block = this->functions_.back().blocks.back();
this->functions_.back().blocks.pop_back();
block->set_end_location(location);
return block;
}
// Add an erroneous name.
Named_object*
Gogo::add_erroneous_name(const std::string& name)
{
return this->package_->bindings()->add_erroneous_name(name);
}
// Add an unknown name.
Named_object*
Gogo::add_unknown_name(const std::string& name, Location location)
{
return this->package_->bindings()->add_unknown_name(name, location);
}
// Declare a function.
Named_object*
Gogo::declare_function(const std::string& name, Function_type* type,
Location location)
{
if (!type->is_method())
return this->current_bindings()->add_function_declaration(name, NULL, type,
location);
else
{
// We don't bother to add this to the list of global
// declarations.
Type* rtype = type->receiver()->type();
// We want to look through the pointer created by the
// parser, without getting an error if the type is not yet
// defined.
if (rtype->classification() == Type::TYPE_POINTER)
rtype = rtype->points_to();
if (rtype->is_error_type())
return NULL;
else if (rtype->named_type() != NULL)
return rtype->named_type()->add_method_declaration(name, NULL, type,
location);
else if (rtype->forward_declaration_type() != NULL)
{
Forward_declaration_type* ftype = rtype->forward_declaration_type();
return ftype->add_method_declaration(name, NULL, type, location);
}
else
{
go_error_at(type->receiver()->location(),
"invalid receiver type (receiver must be a named type)");
return Named_object::make_erroneous_name(name);
}
}
}
// Add a label definition.
Label*
Gogo::add_label_definition(const std::string& label_name,
Location location)
{
go_assert(!this->functions_.empty());
Function* func = this->functions_.back().function->func_value();
Label* label = func->add_label_definition(this, label_name, location);
this->add_statement(Statement::make_label_statement(label, location));
return label;
}
// Add a label reference.
Label*
Gogo::add_label_reference(const std::string& label_name,
Location location, bool issue_goto_errors)
{
go_assert(!this->functions_.empty());
Function* func = this->functions_.back().function->func_value();
return func->add_label_reference(this, label_name, location,
issue_goto_errors);
}
// Return the current binding state.
Bindings_snapshot*
Gogo::bindings_snapshot(Location location)
{
return new Bindings_snapshot(this->current_block(), location);
}
// Add a statement.
void
Gogo::add_statement(Statement* statement)
{
go_assert(!this->functions_.empty()
&& !this->functions_.back().blocks.empty());
this->functions_.back().blocks.back()->add_statement(statement);
}
// Add a block.
void
Gogo::add_block(Block* block, Location location)
{
go_assert(!this->functions_.empty()
&& !this->functions_.back().blocks.empty());
Statement* statement = Statement::make_block_statement(block, location);
this->functions_.back().blocks.back()->add_statement(statement);
}
// Add a constant.
Named_object*
Gogo::add_constant(const Typed_identifier& tid, Expression* expr,
int iota_value)
{
return this->current_bindings()->add_constant(tid, NULL, expr, iota_value);
}
// Add a type.
void
Gogo::add_type(const std::string& name, Type* type, Location location)
{
Named_object* no = this->current_bindings()->add_type(name, NULL, type,
location);
if (!this->in_global_scope() && no->is_type())
{
Named_object* f = this->functions_.back().function;
unsigned int index;
if (f->is_function())
index = f->func_value()->new_local_type_index();
else
index = 0;
no->type_value()->set_in_function(f, index);
}
}
// Add a named type.
void
Gogo::add_named_type(Named_type* type)
{
go_assert(this->in_global_scope());
this->current_bindings()->add_named_type(type);
}
// Declare a type.
Named_object*
Gogo::declare_type(const std::string& name, Location location)
{
Bindings* bindings = this->current_bindings();
Named_object* no = bindings->add_type_declaration(name, NULL, location);
if (!this->in_global_scope() && no->is_type_declaration())
{
Named_object* f = this->functions_.back().function;
unsigned int index;
if (f->is_function())
index = f->func_value()->new_local_type_index();
else
index = 0;
no->type_declaration_value()->set_in_function(f, index);
}
return no;
}
// Declare a type at the package level.
Named_object*
Gogo::declare_package_type(const std::string& name, Location location)
{
return this->package_->bindings()->add_type_declaration(name, NULL, location);
}
// Declare a function at the package level.
Named_object*
Gogo::declare_package_function(const std::string& name, Function_type* type,
Location location)
{
return this->package_->bindings()->add_function_declaration(name, NULL, type,
location);
}
// Add a function declaration to the list of functions we may want to
// inline.
void
Gogo::add_imported_inlinable_function(Named_object* no)
{
go_assert(no->is_function_declaration());
Function_declaration* fd = no->func_declaration_value();
if (fd->is_on_inlinable_list())
return;
this->imported_inlinable_functions_.push_back(no);
fd->set_is_on_inlinable_list();
}
// Define a type which was already declared.
void
Gogo::define_type(Named_object* no, Named_type* type)
{
this->current_bindings()->define_type(no, type);
}
// Add a variable.
Named_object*
Gogo::add_variable(const std::string& name, Variable* variable)
{
Named_object* no = this->current_bindings()->add_variable(name, NULL,
variable);
// In a function the middle-end wants to see a DECL_EXPR node.
if (no != NULL
&& no->is_variable()
&& !no->var_value()->is_parameter()
&& !this->functions_.empty())
this->add_statement(Statement::make_variable_declaration(no));
return no;
}
// Add a sink--a reference to the blank identifier _.
Named_object*
Gogo::add_sink()
{
return Named_object::make_sink();
}
// Add a named object for a dot import.
void
Gogo::add_dot_import_object(Named_object* no)
{
// If the name already exists, then it was defined in some file seen
// earlier. If the earlier name is just a declaration, don't add
// this name, because that will cause the previous declaration to
// merge to this imported name, which should not happen. Just add
// this name to the list of file block names to get appropriate
// errors if we see a later definition.
Named_object* e = this->package_->bindings()->lookup(no->name());
if (e != NULL && e->package() == NULL)
{
if (e->is_unknown())
e = e->resolve();
if (e->package() == NULL
&& (e->is_type_declaration()
|| e->is_function_declaration()
|| e->is_unknown()))
{
this->add_file_block_name(no->name(), no->location());
return;
}
}
this->current_bindings()->add_named_object(no);
}
// Add a linkname. This implements the go:linkname compiler directive.
// We only support this for functions and function declarations.
void
Gogo::add_linkname(const std::string& go_name, bool is_exported,
const std::string& ext_name, Location loc)
{
Named_object* no =
this->package_->bindings()->lookup(this->pack_hidden_name(go_name,
is_exported));
if (no == NULL)
go_error_at(loc, "%s is not defined", go_name.c_str());
else if (no->is_function())
no->func_value()->set_asm_name(ext_name);
else if (no->is_function_declaration())
no->func_declaration_value()->set_asm_name(ext_name);
else
go_error_at(loc,
("%s is not a function; "
"//go:linkname is only supported for functions"),
go_name.c_str());
}
// Mark all local variables used. This is used when some types of
// parse error occur.
void
Gogo::mark_locals_used()
{
for (Open_functions::iterator pf = this->functions_.begin();
pf != this->functions_.end();
++pf)
{
for (std::vector<Block*>::iterator pb = pf->blocks.begin();
pb != pf->blocks.end();
++pb)
(*pb)->bindings()->mark_locals_used();
}
}
// Record that we've seen an interface type.
void
Gogo::record_interface_type(Interface_type* itype)
{
this->interface_types_.push_back(itype);
}
// Define the global names. We do this only after parsing all the
// input files, because the program might define the global names
// itself.
void
Gogo::define_global_names()
{
if (this->is_main_package())
{
// Every Go program has to import the runtime package, so that
// it is properly initialized.
this->import_package("runtime", "_", false, false,
Linemap::predeclared_location());
}
for (Bindings::const_declarations_iterator p =
this->globals_->begin_declarations();
p != this->globals_->end_declarations();
++p)
{
Named_object* global_no = p->second;
std::string name(Gogo::pack_hidden_name(global_no->name(), false));
Named_object* no = this->package_->bindings()->lookup(name);
if (no == NULL)
continue;
no = no->resolve();
if (no->is_type_declaration())
{
if (global_no->is_type())
{
if (no->type_declaration_value()->has_methods())
{
for (std::vector<Named_object*>::const_iterator p =
no->type_declaration_value()->methods()->begin();
p != no->type_declaration_value()->methods()->end();
p++)
go_error_at((*p)->location(),
"may not define methods on non-local type");
}
no->set_type_value(global_no->type_value());
}
else
{
go_error_at(no->location(), "expected type");
Type* errtype = Type::make_error_type();
Named_object* err =
Named_object::make_type("erroneous_type", NULL, errtype,
Linemap::predeclared_location());
no->set_type_value(err->type_value());
}
}
else if (no->is_unknown())
no->unknown_value()->set_real_named_object(global_no);
}
// Give an error if any name is defined in both the package block
// and the file block. For example, this can happen if one file
// imports "fmt" and another file defines a global variable fmt.
for (Bindings::const_declarations_iterator p =
this->package_->bindings()->begin_declarations();
p != this->package_->bindings()->end_declarations();
++p)
{
if (p->second->is_unknown()
&& p->second->unknown_value()->real_named_object() == NULL)
{
// No point in warning about an undefined name, as we will
// get other errors later anyhow.
continue;
}
File_block_names::const_iterator pf =
this->file_block_names_.find(p->second->name());
if (pf != this->file_block_names_.end())
{
std::string n = p->second->message_name();
go_error_at(p->second->location(),
"%qs defined as both imported name and global name",
n.c_str());
go_inform(pf->second, "%qs imported here", n.c_str());
}
// No package scope identifier may be named "init".
if (!p->second->is_function()
&& Gogo::unpack_hidden_name(p->second->name()) == "init")
{
go_error_at(p->second->location(),
"cannot declare init - must be func");
}
}
}
// Clear out names in file scope.
void
Gogo::clear_file_scope()
{
this->package_->bindings()->clear_file_scope(this);
// Warn about packages which were imported but not used.
bool quiet = saw_errors();
for (Packages::iterator p = this->packages_.begin();
p != this->packages_.end();
++p)
{
Package* package = p->second;
if (package != this->package_ && !quiet)
{
for (Package::Aliases::const_iterator p1 = package->aliases().begin();
p1 != package->aliases().end();
++p1)
{
if (!p1->second->used())
{
// Give a more refined error message if the alias name is known.
std::string pkg_name = package->package_name();
if (p1->first != pkg_name && p1->first[0] != '.')
{
go_error_at(p1->second->location(),
"imported and not used: %s as %s",
Gogo::message_name(pkg_name).c_str(),
Gogo::message_name(p1->first).c_str());
}
else
go_error_at(p1->second->location(),
"imported and not used: %s",
Gogo::message_name(pkg_name).c_str());
}
}
}
package->clear_used();
}
this->current_file_imported_unsafe_ = false;
}
// Queue up a type specific function for later writing. These are
// written out in write_specific_type_functions, called after the
// parse tree is lowered.
void
Gogo::queue_specific_type_function(Type* type, Named_type* name, int64_t size,
const std::string& hash_name,
Function_type* hash_fntype,
const std::string& equal_name,
Function_type* equal_fntype)
{
go_assert(!this->specific_type_functions_are_written_);
go_assert(!this->in_global_scope());
Specific_type_function* tsf = new Specific_type_function(type, name, size,
hash_name,
hash_fntype,
equal_name,
equal_fntype);
this->specific_type_functions_.push_back(tsf);
}
// Look for types which need specific hash or equality functions.
class Specific_type_functions : public Traverse
{
public:
Specific_type_functions(Gogo* gogo)
: Traverse(traverse_types),
gogo_(gogo)
{ }
int
type(Type*);
private:
Gogo* gogo_;
};
int
Specific_type_functions::type(Type* t)
{
Named_object* hash_fn;
Named_object* equal_fn;
switch (t->classification())
{
case Type::TYPE_NAMED:
{
Named_type* nt = t->named_type();
if (nt->is_alias())
return TRAVERSE_CONTINUE;
if (t->needs_specific_type_functions(this->gogo_))
t->type_functions(this->gogo_, nt, NULL, NULL, &hash_fn, &equal_fn);
// If this is a struct type, we don't want to make functions
// for the unnamed struct.
Type* rt = nt->real_type();
if (rt->struct_type() == NULL)
{
if (Type::traverse(rt, this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
else
{
// If this type is defined in another package, then we don't
// need to worry about the unexported fields.
bool is_defined_elsewhere = nt->named_object()->package() != NULL;
const Struct_field_list* fields = rt->struct_type()->fields();
for (Struct_field_list::const_iterator p = fields->begin();
p != fields->end();
++p)
{
if (is_defined_elsewhere
&& Gogo::is_hidden_name(p->field_name()))
continue;
if (Type::traverse(p->type(), this) == TRAVERSE_EXIT)
return TRAVERSE_EXIT;
}
}
return TRAVERSE_SKIP_COMPONENTS;
}
case Type::TYPE_STRUCT:
case Type::TYPE_ARRAY:
if (t->needs_specific_type_functions(this->gogo_))
t->type_functions(this->gogo_, NULL, NULL, NULL, &hash_fn, &equal_fn);
break;
default:
break;
}
return TRAVERSE_CONTINUE;
}
// Write out type specific functions.
void
Gogo::write_specific_type_functions()
{
Specific_type_functions stf(this);
this->traverse(&stf);
while (!this->specific_type_functions_.empty())
{
Specific_type_function* tsf = this->specific_type_functions_.back();
this->specific_type_functions_.pop_back();
tsf->type->write_specific_type_functions(this, tsf->name, tsf->size,
tsf->hash_name,
tsf->hash_fntype,
tsf->equal_name,
tsf->equal_fntype);
delete tsf;
}
this->specific_type_functions_are_written_ = true;
}
// Traverse the tree.
void
Gogo::traverse(Traverse* traverse)
{
// Traverse the current package first for consistency. The other
// packages will only contain imported types, constants, and
// declarations.
if (this->package_->bindings()->traverse(traverse, true) == TRAVERSE_EXIT)
return;
for (Packages::const_iterator p = this->packages_.begin();
p != this->packages_.end();
++p)
{
if (p->second != this->package_)
{
if (p->second->bindings()->traverse(traverse, true) == TRAVERSE_EXIT)
break;
}
}
}
// Add a type to verify. This is used for types of sink variables, in
// order to give appropriate error messages.
void
Gogo::add_type_to_verify(Type* type)
{
this->verify_types_.push_back(type);
}
// Traversal class used to verify types.
class Verify_types : public Traverse
{
public:
Verify_types()
: Traverse(traverse_types)
{ }
int
type(Type*);
};
// Verify that a type is correct.
int
Verify_types::type(Type* t)
{
if (!t->verify())
return TRAVERSE_SKIP_COMPONENTS;
return TRAVERSE_CONTINUE;
}
// Verify that all types are correct.
void
Gogo::verify_types()
{
Verify_types traverse;
this->traverse(&traverse);
for (std::vector<Type*>::iterator p = this->verify_types_.begin();
p != this->verify_types_.end();
++p)
(*p)->verify();
this->verify_types_.clear();
}
// Traversal class used to lower parse tree.
class Lower_parse_tree : public Traverse
{
public:
Lower_parse_tree(G