1 // gogo-tree.cc -- convert Go frontend Gogo IR to gcc trees.
3 // Copyright 2009 The Go Authors. All rights reserved.
4 // Use of this source code is governed by a BSD-style
5 // license that can be found in the LICENSE file.
11 #ifndef ENABLE_BUILD_WITH_CXX
19 #include "tree-iterator.h"
21 #include "langhooks.h"
24 #include "diagnostic.h"
26 #ifndef ENABLE_BUILD_WITH_CXX
32 #include "expressions.h"
33 #include "statements.h"
38 // Whether we have seen any errors.
43 return errorcount != 0 || sorrycount != 0;
49 get_identifier_from_string(const std::string& str)
51 return get_identifier_with_length(str.data(), str.length());
56 static std::map<std::string, tree> builtin_functions;
58 // Define a builtin function. BCODE is the builtin function code
59 // defined by builtins.def. NAME is the name of the builtin function.
60 // LIBNAME is the name of the corresponding library function, and is
61 // NULL if there isn't one. FNTYPE is the type of the function.
62 // CONST_P is true if the function has the const attribute.
65 define_builtin(built_in_function bcode, const char* name, const char* libname,
66 tree fntype, bool const_p)
68 tree decl = add_builtin_function(name, fntype, bcode, BUILT_IN_NORMAL,
71 TREE_READONLY(decl) = 1;
72 built_in_decls[bcode] = decl;
73 implicit_built_in_decls[bcode] = decl;
74 builtin_functions[name] = decl;
77 decl = add_builtin_function(libname, fntype, bcode, BUILT_IN_NORMAL,
80 TREE_READONLY(decl) = 1;
81 builtin_functions[libname] = decl;
85 // Create trees for implicit builtin functions.
88 Gogo::define_builtin_function_trees()
90 /* We need to define the fetch_and_add functions, since we use them
92 tree t = go_type_for_size(BITS_PER_UNIT, 1);
93 tree p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE));
94 define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_1, "__sync_fetch_and_add_1", NULL,
95 build_function_type_list(t, p, t, NULL_TREE), false);
97 t = go_type_for_size(BITS_PER_UNIT * 2, 1);
98 p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE));
99 define_builtin (BUILT_IN_SYNC_ADD_AND_FETCH_2, "__sync_fetch_and_add_2", NULL,
100 build_function_type_list(t, p, t, NULL_TREE), false);
102 t = go_type_for_size(BITS_PER_UNIT * 4, 1);
103 p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE));
104 define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_4, "__sync_fetch_and_add_4", NULL,
105 build_function_type_list(t, p, t, NULL_TREE), false);
107 t = go_type_for_size(BITS_PER_UNIT * 8, 1);
108 p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE));
109 define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_8, "__sync_fetch_and_add_8", NULL,
110 build_function_type_list(t, p, t, NULL_TREE), false);
112 // We use __builtin_expect for magic import functions.
113 define_builtin(BUILT_IN_EXPECT, "__builtin_expect", NULL,
114 build_function_type_list(long_integer_type_node,
115 long_integer_type_node,
116 long_integer_type_node,
120 // We use __builtin_memmove for the predeclared copy function.
121 define_builtin(BUILT_IN_MEMMOVE, "__builtin_memmove", "memmove",
122 build_function_type_list(ptr_type_node,
129 // We provide sqrt for the math library.
130 define_builtin(BUILT_IN_SQRT, "__builtin_sqrt", "sqrt",
131 build_function_type_list(double_type_node,
135 define_builtin(BUILT_IN_SQRTL, "__builtin_sqrtl", "sqrtl",
136 build_function_type_list(long_double_type_node,
137 long_double_type_node,
141 // We use __builtin_return_address in the thunk we build for
142 // functions which call recover.
143 define_builtin(BUILT_IN_RETURN_ADDRESS, "__builtin_return_address", NULL,
144 build_function_type_list(ptr_type_node,
149 // The compiler uses __builtin_trap for some exception handling
151 define_builtin(BUILT_IN_TRAP, "__builtin_trap", NULL,
152 build_function_type(void_type_node, void_list_node),
156 // Get the name to use for the import control function. If there is a
157 // global function or variable, then we know that that name must be
158 // unique in the link, and we use it as the basis for our name.
161 Gogo::get_init_fn_name()
163 if (this->init_fn_name_.empty())
165 go_assert(this->package_ != NULL);
166 if (this->is_main_package())
168 // Use a name which the runtime knows.
169 this->init_fn_name_ = "__go_init_main";
173 std::string s = this->unique_prefix();
175 s.append(this->package_name());
176 s.append("..import");
177 this->init_fn_name_ = s;
181 return this->init_fn_name_;
184 // Add statements to INIT_STMT_LIST which run the initialization
185 // functions for imported packages. This is only used for the "main"
189 Gogo::init_imports(tree* init_stmt_list)
191 go_assert(this->is_main_package());
193 if (this->imported_init_fns_.empty())
196 tree fntype = build_function_type(void_type_node, void_list_node);
198 // We must call them in increasing priority order.
199 std::vector<Import_init> v;
200 for (std::set<Import_init>::const_iterator p =
201 this->imported_init_fns_.begin();
202 p != this->imported_init_fns_.end();
205 std::sort(v.begin(), v.end());
207 for (std::vector<Import_init>::const_iterator p = v.begin();
211 std::string user_name = p->package_name() + ".init";
212 tree decl = build_decl(UNKNOWN_LOCATION, FUNCTION_DECL,
213 get_identifier_from_string(user_name),
215 const std::string& init_name(p->init_name());
216 SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(init_name));
217 TREE_PUBLIC(decl) = 1;
218 DECL_EXTERNAL(decl) = 1;
219 append_to_statement_list(build_call_expr(decl, 0), init_stmt_list);
223 // Register global variables with the garbage collector. We need to
224 // register all variables which can hold a pointer value. They become
225 // roots during the mark phase. We build a struct that is easy to
226 // hook into a list of roots.
228 // struct __go_gc_root_list
230 // struct __go_gc_root_list* __next;
231 // struct __go_gc_root
238 // The last entry in the roots array has a NULL decl field.
241 Gogo::register_gc_vars(const std::vector<Named_object*>& var_gc,
242 tree* init_stmt_list)
247 size_t count = var_gc.size();
249 tree root_type = Gogo::builtin_struct(NULL, "__go_gc_root", NULL_TREE, 2,
255 tree index_type = build_index_type(size_int(count));
256 tree array_type = build_array_type(root_type, index_type);
258 tree root_list_type = make_node(RECORD_TYPE);
259 root_list_type = Gogo::builtin_struct(NULL, "__go_gc_root_list",
262 build_pointer_type(root_list_type),
266 // Build an initialier for the __roots array.
268 VEC(constructor_elt,gc)* roots_init = VEC_alloc(constructor_elt, gc,
272 for (std::vector<Named_object*>::const_iterator p = var_gc.begin();
276 VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2);
278 constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL);
279 tree field = TYPE_FIELDS(root_type);
281 Bvariable* bvar = (*p)->get_backend_variable(this, NULL);
282 tree decl = var_to_tree(bvar);
283 go_assert(TREE_CODE(decl) == VAR_DECL);
284 elt->value = build_fold_addr_expr(decl);
286 elt = VEC_quick_push(constructor_elt, init, NULL);
287 field = DECL_CHAIN(field);
289 elt->value = DECL_SIZE_UNIT(decl);
291 elt = VEC_quick_push(constructor_elt, roots_init, NULL);
292 elt->index = size_int(i);
293 elt->value = build_constructor(root_type, init);
296 // The list ends with a NULL entry.
298 VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2);
300 constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL);
301 tree field = TYPE_FIELDS(root_type);
303 elt->value = fold_convert(TREE_TYPE(field), null_pointer_node);
305 elt = VEC_quick_push(constructor_elt, init, NULL);
306 field = DECL_CHAIN(field);
308 elt->value = size_zero_node;
310 elt = VEC_quick_push(constructor_elt, roots_init, NULL);
311 elt->index = size_int(i);
312 elt->value = build_constructor(root_type, init);
314 // Build a constructor for the struct.
316 VEC(constructor_elt,gc*) root_list_init = VEC_alloc(constructor_elt, gc, 2);
318 elt = VEC_quick_push(constructor_elt, root_list_init, NULL);
319 field = TYPE_FIELDS(root_list_type);
321 elt->value = fold_convert(TREE_TYPE(field), null_pointer_node);
323 elt = VEC_quick_push(constructor_elt, root_list_init, NULL);
324 field = DECL_CHAIN(field);
326 elt->value = build_constructor(array_type, roots_init);
328 // Build a decl to register.
330 tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL,
331 create_tmp_var_name("gc"), root_list_type);
332 DECL_EXTERNAL(decl) = 0;
333 TREE_PUBLIC(decl) = 0;
334 TREE_STATIC(decl) = 1;
335 DECL_ARTIFICIAL(decl) = 1;
336 DECL_INITIAL(decl) = build_constructor(root_list_type, root_list_init);
337 rest_of_decl_compilation(decl, 1, 0);
339 static tree register_gc_fndecl;
340 tree call = Gogo::call_builtin(®ister_gc_fndecl, BUILTINS_LOCATION,
341 "__go_register_gc_roots",
344 build_pointer_type(root_list_type),
345 build_fold_addr_expr(decl));
346 if (call != error_mark_node)
347 append_to_statement_list(call, init_stmt_list);
350 // Build the decl for the initialization function.
353 Gogo::initialization_function_decl()
355 // The tedious details of building your own function. There doesn't
356 // seem to be a helper function for this.
357 std::string name = this->package_name() + ".init";
358 tree fndecl = build_decl(BUILTINS_LOCATION, FUNCTION_DECL,
359 get_identifier_from_string(name),
360 build_function_type(void_type_node,
362 const std::string& asm_name(this->get_init_fn_name());
363 SET_DECL_ASSEMBLER_NAME(fndecl, get_identifier_from_string(asm_name));
365 tree resdecl = build_decl(BUILTINS_LOCATION, RESULT_DECL, NULL_TREE,
367 DECL_ARTIFICIAL(resdecl) = 1;
368 DECL_CONTEXT(resdecl) = fndecl;
369 DECL_RESULT(fndecl) = resdecl;
371 TREE_STATIC(fndecl) = 1;
372 TREE_USED(fndecl) = 1;
373 DECL_ARTIFICIAL(fndecl) = 1;
374 TREE_PUBLIC(fndecl) = 1;
376 DECL_INITIAL(fndecl) = make_node(BLOCK);
377 TREE_USED(DECL_INITIAL(fndecl)) = 1;
382 // Create the magic initialization function. INIT_STMT_LIST is the
383 // code that it needs to run.
386 Gogo::write_initialization_function(tree fndecl, tree init_stmt_list)
388 // Make sure that we thought we needed an initialization function,
389 // as otherwise we will not have reported it in the export data.
390 go_assert(this->is_main_package() || this->need_init_fn_);
392 if (fndecl == NULL_TREE)
393 fndecl = this->initialization_function_decl();
395 DECL_SAVED_TREE(fndecl) = init_stmt_list;
397 current_function_decl = fndecl;
398 if (DECL_STRUCT_FUNCTION(fndecl) == NULL)
399 push_struct_function(fndecl);
401 push_cfun(DECL_STRUCT_FUNCTION(fndecl));
402 cfun->function_end_locus = BUILTINS_LOCATION;
404 gimplify_function_tree(fndecl);
406 cgraph_add_new_function(fndecl, false);
407 cgraph_mark_needed_node(cgraph_get_node(fndecl));
409 current_function_decl = NULL_TREE;
413 // Search for references to VAR in any statements or called functions.
415 class Find_var : public Traverse
418 // A hash table we use to avoid looping. The index is the name of a
419 // named object. We only look through objects defined in this
421 typedef Unordered_set(std::string) Seen_objects;
423 Find_var(Named_object* var, Seen_objects* seen_objects)
424 : Traverse(traverse_expressions),
425 var_(var), seen_objects_(seen_objects), found_(false)
428 // Whether the variable was found.
431 { return this->found_; }
434 expression(Expression**);
437 // The variable we are looking for.
439 // Names of objects we have already seen.
440 Seen_objects* seen_objects_;
441 // True if the variable was found.
445 // See if EXPR refers to VAR, looking through function calls and
446 // variable initializations.
449 Find_var::expression(Expression** pexpr)
451 Expression* e = *pexpr;
453 Var_expression* ve = e->var_expression();
456 Named_object* v = ve->named_object();
460 return TRAVERSE_EXIT;
463 if (v->is_variable() && v->package() == NULL)
465 Expression* init = v->var_value()->init();
468 std::pair<Seen_objects::iterator, bool> ins =
469 this->seen_objects_->insert(v->name());
472 // This is the first time we have seen this name.
473 if (Expression::traverse(&init, this) == TRAVERSE_EXIT)
474 return TRAVERSE_EXIT;
480 // We traverse the code of any function we see. Note that this
481 // means that we will traverse the code of a function whose address
482 // is taken even if it is not called.
483 Func_expression* fe = e->func_expression();
486 const Named_object* f = fe->named_object();
487 if (f->is_function() && f->package() == NULL)
489 std::pair<Seen_objects::iterator, bool> ins =
490 this->seen_objects_->insert(f->name());
493 // This is the first time we have seen this name.
494 if (f->func_value()->block()->traverse(this) == TRAVERSE_EXIT)
495 return TRAVERSE_EXIT;
500 return TRAVERSE_CONTINUE;
503 // Return true if EXPR refers to VAR.
506 expression_requires(Expression* expr, Block* preinit, Named_object* var)
508 Find_var::Seen_objects seen_objects;
509 Find_var find_var(var, &seen_objects);
511 Expression::traverse(&expr, &find_var);
513 preinit->traverse(&find_var);
515 return find_var.found();
518 // Sort variable initializations. If the initialization expression
519 // for variable A refers directly or indirectly to the initialization
520 // expression for variable B, then we must initialize B before A.
526 : var_(NULL), init_(NULL_TREE), waiting_(0)
529 Var_init(Named_object* var, tree init)
530 : var_(var), init_(init), waiting_(0)
533 // Return the variable.
536 { return this->var_; }
538 // Return the initialization expression.
541 { return this->init_; }
543 // Return the number of variables waiting for this one to be
547 { return this->waiting_; }
549 // Increment the number waiting.
552 { ++this->waiting_; }
555 // The variable being initialized.
557 // The initialization expression to run.
559 // The number of variables which are waiting for this one.
563 typedef std::list<Var_init> Var_inits;
565 // Sort the variable initializations. The rule we follow is that we
566 // emit them in the order they appear in the array, except that if the
567 // initialization expression for a variable V1 depends upon another
568 // variable V2 then we initialize V1 after V2.
571 sort_var_inits(Var_inits* var_inits)
574 while (!var_inits->empty())
576 Var_inits::iterator p1 = var_inits->begin();
577 Named_object* var = p1->var();
578 Expression* init = var->var_value()->init();
579 Block* preinit = var->var_value()->preinit();
581 // Start walking through the list to see which variables VAR
582 // needs to wait for. We can skip P1->WAITING variables--that
583 // is the number we've already checked.
584 Var_inits::iterator p2 = p1;
586 for (size_t i = p1->waiting(); i > 0; --i)
589 for (; p2 != var_inits->end(); ++p2)
591 if (expression_requires(init, preinit, p2->var()))
594 if (expression_requires(p2->var()->var_value()->init(),
595 p2->var()->var_value()->preinit(),
598 error_at(var->location(),
599 ("initialization expressions for %qs and "
600 "%qs depend upon each other"),
601 var->message_name().c_str(),
602 p2->var()->message_name().c_str());
603 inform(p2->var()->location(), "%qs defined here",
604 p2->var()->message_name().c_str());
605 p2 = var_inits->end();
609 // We can't emit P1 until P2 is emitted. Move P1.
610 // Note that the WAITING loop always executes at
611 // least once, which is what we want.
612 p2->increment_waiting();
613 Var_inits::iterator p3 = p2;
614 for (size_t i = p2->waiting(); i > 0; --i)
616 var_inits->splice(p3, *var_inits, p1);
622 if (p2 == var_inits->end())
624 // VAR does not depends upon any other initialization expressions.
626 // Check for a loop of VAR on itself. We only do this if
627 // INIT is not NULL; when INIT is NULL, it means that
628 // PREINIT sets VAR, which we will interpret as a loop.
629 if (init != NULL && expression_requires(init, preinit, var))
630 error_at(var->location(),
631 "initialization expression for %qs depends upon itself",
632 var->message_name().c_str());
633 ready.splice(ready.end(), *var_inits, p1);
637 // Now READY is the list in the desired initialization order.
638 var_inits->swap(ready);
641 // Write out the global definitions.
644 Gogo::write_globals()
646 this->convert_named_types();
647 this->build_interface_method_tables();
649 Bindings* bindings = this->current_bindings();
650 size_t count = bindings->size_definitions();
652 tree* vec = new tree[count];
654 tree init_fndecl = NULL_TREE;
655 tree init_stmt_list = NULL_TREE;
657 if (this->is_main_package())
658 this->init_imports(&init_stmt_list);
660 // A list of variable initializations.
663 // A list of variables which need to be registered with the garbage
665 std::vector<Named_object*> var_gc;
666 var_gc.reserve(count);
668 tree var_init_stmt_list = NULL_TREE;
670 for (Bindings::const_definitions_iterator p = bindings->begin_definitions();
671 p != bindings->end_definitions();
674 Named_object* no = *p;
676 go_assert(!no->is_type_declaration() && !no->is_function_declaration());
677 // There is nothing to do for a package.
678 if (no->is_package())
685 // There is nothing to do for an object which was imported from
686 // a different package into the global scope.
687 if (no->package() != NULL)
694 // There is nothing useful we can output for constants which
695 // have ideal or non-integeral type.
698 Type* type = no->const_value()->type();
700 type = no->const_value()->expr()->type();
701 if (type->is_abstract() || type->integer_type() == NULL)
709 if (!no->is_variable())
711 vec[i] = no->get_tree(this, NULL);
712 if (vec[i] == error_mark_node)
714 go_assert(saw_errors());
722 Bvariable* var = no->get_backend_variable(this, NULL);
723 vec[i] = var_to_tree(var);
724 if (vec[i] == error_mark_node)
726 go_assert(saw_errors());
732 // Check for a sink variable, which may be used to run an
733 // initializer purely for its side effects.
734 bool is_sink = no->name()[0] == '_' && no->name()[1] == '.';
736 tree var_init_tree = NULL_TREE;
737 if (!no->var_value()->has_pre_init())
739 tree init = no->var_value()->get_init_tree(this, NULL);
740 if (init == error_mark_node)
741 go_assert(saw_errors());
742 else if (init == NULL_TREE)
744 else if (TREE_CONSTANT(init))
745 this->backend()->global_variable_set_init(var,
748 var_init_tree = init;
750 var_init_tree = fold_build2_loc(no->location(), MODIFY_EXPR,
751 void_type_node, vec[i], init);
755 // We are going to create temporary variables which
756 // means that we need an fndecl.
757 if (init_fndecl == NULL_TREE)
758 init_fndecl = this->initialization_function_decl();
759 current_function_decl = init_fndecl;
760 if (DECL_STRUCT_FUNCTION(init_fndecl) == NULL)
761 push_struct_function(init_fndecl);
763 push_cfun(DECL_STRUCT_FUNCTION(init_fndecl));
765 tree var_decl = is_sink ? NULL_TREE : vec[i];
766 var_init_tree = no->var_value()->get_init_block(this, NULL,
769 current_function_decl = NULL_TREE;
773 if (var_init_tree != NULL_TREE && var_init_tree != error_mark_node)
775 if (no->var_value()->init() == NULL
776 && !no->var_value()->has_pre_init())
777 append_to_statement_list(var_init_tree, &var_init_stmt_list);
779 var_inits.push_back(Var_init(no, var_init_tree));
782 if (!is_sink && no->var_value()->type()->has_pointer())
783 var_gc.push_back(no);
787 // Register global variables with the garbage collector.
788 this->register_gc_vars(var_gc, &init_stmt_list);
790 // Simple variable initializations, after all variables are
792 append_to_statement_list(var_init_stmt_list, &init_stmt_list);
794 // Complex variable initializations, first sorting them into a
796 if (!var_inits.empty())
798 sort_var_inits(&var_inits);
799 for (Var_inits::const_iterator p = var_inits.begin();
800 p != var_inits.end();
802 append_to_statement_list(p->init(), &init_stmt_list);
805 // After all the variables are initialized, call the "init"
806 // functions if there are any.
807 for (std::vector<Named_object*>::const_iterator p =
808 this->init_functions_.begin();
809 p != this->init_functions_.end();
812 tree decl = (*p)->get_tree(this, NULL);
813 tree call = build_call_expr(decl, 0);
814 append_to_statement_list(call, &init_stmt_list);
817 // Set up a magic function to do all the initialization actions.
818 // This will be called if this package is imported.
819 if (init_stmt_list != NULL_TREE
820 || this->need_init_fn_
821 || this->is_main_package())
822 this->write_initialization_function(init_fndecl, init_stmt_list);
824 // Pass everything back to the middle-end.
826 wrapup_global_declarations(vec, count);
828 cgraph_finalize_compilation_unit();
830 check_global_declarations(vec, count);
831 emit_debug_global_declarations(vec, count);
836 // Get a tree for the identifier for a named object.
839 Named_object::get_id(Gogo* gogo)
841 go_assert(!this->is_variable() && !this->is_result_variable());
842 std::string decl_name;
843 if (this->is_function_declaration()
844 && !this->func_declaration_value()->asm_name().empty())
845 decl_name = this->func_declaration_value()->asm_name();
846 else if (this->is_type()
847 && this->type_value()->location() == BUILTINS_LOCATION)
849 // We don't need the package name for builtin types.
850 decl_name = Gogo::unpack_hidden_name(this->name_);
854 std::string package_name;
855 if (this->package_ == NULL)
856 package_name = gogo->package_name();
858 package_name = this->package_->name();
860 decl_name = package_name + '.' + Gogo::unpack_hidden_name(this->name_);
862 Function_type* fntype;
863 if (this->is_function())
864 fntype = this->func_value()->type();
865 else if (this->is_function_declaration())
866 fntype = this->func_declaration_value()->type();
869 if (fntype != NULL && fntype->is_method())
871 decl_name.push_back('.');
872 decl_name.append(fntype->receiver()->type()->mangled_name(gogo));
877 const Named_object* in_function = this->type_value()->in_function();
878 if (in_function != NULL)
879 decl_name += '$' + in_function->name();
881 return get_identifier_from_string(decl_name);
884 // Get a tree for a named object.
887 Named_object::get_tree(Gogo* gogo, Named_object* function)
889 if (this->tree_ != NULL_TREE)
893 if (this->classification_ == NAMED_OBJECT_TYPE)
896 name = this->get_id(gogo);
898 switch (this->classification_)
900 case NAMED_OBJECT_CONST:
902 Named_constant* named_constant = this->u_.const_value;
903 Translate_context subcontext(gogo, function, NULL, NULL);
904 tree expr_tree = named_constant->expr()->get_tree(&subcontext);
905 if (expr_tree == error_mark_node)
906 decl = error_mark_node;
909 Type* type = named_constant->type();
910 if (type != NULL && !type->is_abstract())
912 if (type->is_error())
913 expr_tree = error_mark_node;
916 Btype* btype = type->get_backend(gogo);
917 expr_tree = fold_convert(type_to_tree(btype), expr_tree);
920 if (expr_tree == error_mark_node)
921 decl = error_mark_node;
922 else if (INTEGRAL_TYPE_P(TREE_TYPE(expr_tree)))
924 decl = build_decl(named_constant->location(), CONST_DECL,
925 name, TREE_TYPE(expr_tree));
926 DECL_INITIAL(decl) = expr_tree;
927 TREE_CONSTANT(decl) = 1;
928 TREE_READONLY(decl) = 1;
932 // A CONST_DECL is only for an enum constant, so we
933 // shouldn't use for non-integral types. Instead we
934 // just return the constant itself, rather than a
942 case NAMED_OBJECT_TYPE:
944 Named_type* named_type = this->u_.type_value;
945 tree type_tree = type_to_tree(named_type->get_backend(gogo));
946 if (type_tree == error_mark_node)
947 decl = error_mark_node;
950 decl = TYPE_NAME(type_tree);
951 go_assert(decl != NULL_TREE);
953 // We need to produce a type descriptor for every named
954 // type, and for a pointer to every named type, since
955 // other files or packages might refer to them. We need
956 // to do this even for hidden types, because they might
957 // still be returned by some function. Simply calling the
958 // type_descriptor method is enough to create the type
959 // descriptor, even though we don't do anything with it.
960 if (this->package_ == NULL)
962 named_type->type_descriptor_pointer(gogo, BUILTINS_LOCATION);
963 Type* pn = Type::make_pointer_type(named_type);
964 pn->type_descriptor_pointer(gogo, BUILTINS_LOCATION);
970 case NAMED_OBJECT_TYPE_DECLARATION:
971 error("reference to undefined type %qs",
972 this->message_name().c_str());
973 return error_mark_node;
975 case NAMED_OBJECT_VAR:
976 case NAMED_OBJECT_RESULT_VAR:
977 case NAMED_OBJECT_SINK:
980 case NAMED_OBJECT_FUNC:
982 Function* func = this->u_.func_value;
983 decl = func->get_or_make_decl(gogo, this, name);
984 if (decl != error_mark_node)
986 if (func->block() != NULL)
988 if (DECL_STRUCT_FUNCTION(decl) == NULL)
989 push_struct_function(decl);
991 push_cfun(DECL_STRUCT_FUNCTION(decl));
993 cfun->function_end_locus = func->block()->end_location();
995 current_function_decl = decl;
997 func->build_tree(gogo, this);
999 gimplify_function_tree(decl);
1001 cgraph_finalize_function(decl, true);
1003 current_function_decl = NULL_TREE;
1014 if (TREE_TYPE(decl) == error_mark_node)
1015 decl = error_mark_node;
1021 if (ret != error_mark_node)
1022 go_preserve_from_gc(ret);
1027 // Get the initial value of a variable as a tree. This does not
1028 // consider whether the variable is in the heap--it returns the
1029 // initial value as though it were always stored in the stack.
1032 Variable::get_init_tree(Gogo* gogo, Named_object* function)
1034 go_assert(this->preinit_ == NULL);
1035 if (this->init_ == NULL)
1037 go_assert(!this->is_parameter_);
1038 if (this->is_global_ || this->is_in_heap())
1040 Btype* btype = this->type_->get_backend(gogo);
1041 return expr_to_tree(gogo->backend()->zero_expression(btype));
1045 Translate_context context(gogo, function, NULL, NULL);
1046 tree rhs_tree = this->init_->get_tree(&context);
1047 return Expression::convert_for_assignment(&context, this->type(),
1048 this->init_->type(),
1049 rhs_tree, this->location());
1053 // Get the initial value of a variable when a block is required.
1054 // VAR_DECL is the decl to set; it may be NULL for a sink variable.
1057 Variable::get_init_block(Gogo* gogo, Named_object* function, tree var_decl)
1059 go_assert(this->preinit_ != NULL);
1061 // We want to add the variable assignment to the end of the preinit
1062 // block. The preinit block may have a TRY_FINALLY_EXPR and a
1063 // TRY_CATCH_EXPR; if it does, we want to add to the end of the
1064 // regular statements.
1066 Translate_context context(gogo, function, NULL, NULL);
1067 Bblock* bblock = this->preinit_->get_backend(&context);
1068 tree block_tree = block_to_tree(bblock);
1069 if (block_tree == error_mark_node)
1070 return error_mark_node;
1071 go_assert(TREE_CODE(block_tree) == BIND_EXPR);
1072 tree statements = BIND_EXPR_BODY(block_tree);
1073 while (statements != NULL_TREE
1074 && (TREE_CODE(statements) == TRY_FINALLY_EXPR
1075 || TREE_CODE(statements) == TRY_CATCH_EXPR))
1076 statements = TREE_OPERAND(statements, 0);
1078 // It's possible to have pre-init statements without an initializer
1079 // if the pre-init statements set the variable.
1080 if (this->init_ != NULL)
1082 tree rhs_tree = this->init_->get_tree(&context);
1083 if (rhs_tree == error_mark_node)
1084 return error_mark_node;
1085 if (var_decl == NULL_TREE)
1086 append_to_statement_list(rhs_tree, &statements);
1089 tree val = Expression::convert_for_assignment(&context, this->type(),
1090 this->init_->type(),
1093 if (val == error_mark_node)
1094 return error_mark_node;
1095 tree set = fold_build2_loc(this->location(), MODIFY_EXPR,
1096 void_type_node, var_decl, val);
1097 append_to_statement_list(set, &statements);
1104 // Get a tree for a function decl.
1107 Function::get_or_make_decl(Gogo* gogo, Named_object* no, tree id)
1109 if (this->fndecl_ == NULL_TREE)
1111 tree functype = type_to_tree(this->type_->get_backend(gogo));
1112 if (functype == error_mark_node)
1113 this->fndecl_ = error_mark_node;
1116 // The type of a function comes back as a pointer, but we
1117 // want the real function type for a function declaration.
1118 go_assert(POINTER_TYPE_P(functype));
1119 functype = TREE_TYPE(functype);
1120 tree decl = build_decl(this->location(), FUNCTION_DECL, id, functype);
1122 this->fndecl_ = decl;
1124 if (no->package() != NULL)
1126 else if (this->enclosing_ != NULL || Gogo::is_thunk(no))
1128 else if (Gogo::unpack_hidden_name(no->name()) == "init"
1129 && !this->type_->is_method())
1131 else if (Gogo::unpack_hidden_name(no->name()) == "main"
1132 && gogo->is_main_package())
1133 TREE_PUBLIC(decl) = 1;
1134 // Methods have to be public even if they are hidden because
1135 // they can be pulled into type descriptors when using
1136 // anonymous fields.
1137 else if (!Gogo::is_hidden_name(no->name())
1138 || this->type_->is_method())
1140 TREE_PUBLIC(decl) = 1;
1141 std::string asm_name = gogo->unique_prefix();
1142 asm_name.append(1, '.');
1143 asm_name.append(IDENTIFIER_POINTER(id), IDENTIFIER_LENGTH(id));
1144 SET_DECL_ASSEMBLER_NAME(decl,
1145 get_identifier_from_string(asm_name));
1148 // Why do we have to do this in the frontend?
1149 tree restype = TREE_TYPE(functype);
1150 tree resdecl = build_decl(this->location(), RESULT_DECL, NULL_TREE,
1152 DECL_ARTIFICIAL(resdecl) = 1;
1153 DECL_IGNORED_P(resdecl) = 1;
1154 DECL_CONTEXT(resdecl) = decl;
1155 DECL_RESULT(decl) = resdecl;
1157 if (this->enclosing_ != NULL)
1158 DECL_STATIC_CHAIN(decl) = 1;
1160 // If a function calls the predeclared recover function, we
1161 // can't inline it, because recover behaves differently in a
1162 // function passed directly to defer.
1163 if (this->calls_recover_ && !this->is_recover_thunk_)
1164 DECL_UNINLINABLE(decl) = 1;
1166 // If this is a thunk created to call a function which calls
1167 // the predeclared recover function, we need to disable
1168 // stack splitting for the thunk.
1169 if (this->is_recover_thunk_)
1171 tree attr = get_identifier("__no_split_stack__");
1172 DECL_ATTRIBUTES(decl) = tree_cons(attr, NULL_TREE, NULL_TREE);
1175 go_preserve_from_gc(decl);
1177 if (this->closure_var_ != NULL)
1179 push_struct_function(decl);
1181 Bvariable* bvar = this->closure_var_->get_backend_variable(gogo,
1183 tree closure_decl = var_to_tree(bvar);
1184 if (closure_decl == error_mark_node)
1185 this->fndecl_ = error_mark_node;
1188 DECL_ARTIFICIAL(closure_decl) = 1;
1189 DECL_IGNORED_P(closure_decl) = 1;
1190 TREE_USED(closure_decl) = 1;
1191 DECL_ARG_TYPE(closure_decl) = TREE_TYPE(closure_decl);
1192 TREE_READONLY(closure_decl) = 1;
1194 DECL_STRUCT_FUNCTION(decl)->static_chain_decl = closure_decl;
1201 return this->fndecl_;
1204 // Get a tree for a function declaration.
1207 Function_declaration::get_or_make_decl(Gogo* gogo, Named_object* no, tree id)
1209 if (this->fndecl_ == NULL_TREE)
1211 // Let Go code use an asm declaration to pick up a builtin
1213 if (!this->asm_name_.empty())
1215 std::map<std::string, tree>::const_iterator p =
1216 builtin_functions.find(this->asm_name_);
1217 if (p != builtin_functions.end())
1219 this->fndecl_ = p->second;
1220 return this->fndecl_;
1224 tree functype = type_to_tree(this->fntype_->get_backend(gogo));
1226 if (functype == error_mark_node)
1227 decl = error_mark_node;
1230 // The type of a function comes back as a pointer, but we
1231 // want the real function type for a function declaration.
1232 go_assert(POINTER_TYPE_P(functype));
1233 functype = TREE_TYPE(functype);
1234 decl = build_decl(this->location(), FUNCTION_DECL, id, functype);
1235 TREE_PUBLIC(decl) = 1;
1236 DECL_EXTERNAL(decl) = 1;
1238 if (this->asm_name_.empty())
1240 std::string asm_name = (no->package() == NULL
1241 ? gogo->unique_prefix()
1242 : no->package()->unique_prefix());
1243 asm_name.append(1, '.');
1244 asm_name.append(IDENTIFIER_POINTER(id), IDENTIFIER_LENGTH(id));
1245 SET_DECL_ASSEMBLER_NAME(decl,
1246 get_identifier_from_string(asm_name));
1249 this->fndecl_ = decl;
1250 go_preserve_from_gc(decl);
1252 return this->fndecl_;
1255 // We always pass the receiver to a method as a pointer. If the
1256 // receiver is actually declared as a non-pointer type, then we copy
1257 // the value into a local variable, so that it has the right type. In
1258 // this function we create the real PARM_DECL to use, and set
1259 // DEC_INITIAL of the var_decl to be the value passed in.
1262 Function::make_receiver_parm_decl(Gogo* gogo, Named_object* no, tree var_decl)
1264 if (var_decl == error_mark_node)
1265 return error_mark_node;
1266 go_assert(TREE_CODE(var_decl) == VAR_DECL);
1267 tree val_type = TREE_TYPE(var_decl);
1268 bool is_in_heap = no->var_value()->is_in_heap();
1271 go_assert(POINTER_TYPE_P(val_type));
1272 val_type = TREE_TYPE(val_type);
1275 source_location loc = DECL_SOURCE_LOCATION(var_decl);
1276 std::string name = IDENTIFIER_POINTER(DECL_NAME(var_decl));
1278 tree id = get_identifier_from_string(name);
1279 tree parm_decl = build_decl(loc, PARM_DECL, id, build_pointer_type(val_type));
1280 DECL_CONTEXT(parm_decl) = current_function_decl;
1281 DECL_ARG_TYPE(parm_decl) = TREE_TYPE(parm_decl);
1283 go_assert(DECL_INITIAL(var_decl) == NULL_TREE);
1284 // The receiver might be passed as a null pointer.
1285 tree check = fold_build2_loc(loc, NE_EXPR, boolean_type_node, parm_decl,
1286 fold_convert_loc(loc, TREE_TYPE(parm_decl),
1287 null_pointer_node));
1288 tree ind = build_fold_indirect_ref_loc(loc, parm_decl);
1289 TREE_THIS_NOTRAP(ind) = 1;
1290 Btype* btype = no->var_value()->type()->get_backend(gogo);
1291 tree zero_init = expr_to_tree(gogo->backend()->zero_expression(btype));
1292 tree init = fold_build3_loc(loc, COND_EXPR, TREE_TYPE(ind),
1293 check, ind, zero_init);
1297 tree size = TYPE_SIZE_UNIT(val_type);
1298 tree space = gogo->allocate_memory(no->var_value()->type(), size,
1300 space = save_expr(space);
1301 space = fold_convert(build_pointer_type(val_type), space);
1302 tree spaceref = build_fold_indirect_ref_loc(no->location(), space);
1303 TREE_THIS_NOTRAP(spaceref) = 1;
1304 tree check = fold_build2_loc(loc, NE_EXPR, boolean_type_node,
1306 fold_convert_loc(loc, TREE_TYPE(parm_decl),
1307 null_pointer_node));
1308 tree parmref = build_fold_indirect_ref_loc(no->location(), parm_decl);
1309 TREE_THIS_NOTRAP(parmref) = 1;
1310 tree set = fold_build2_loc(loc, MODIFY_EXPR, void_type_node,
1312 init = fold_build2_loc(loc, COMPOUND_EXPR, TREE_TYPE(space),
1313 build3(COND_EXPR, void_type_node,
1314 check, set, NULL_TREE),
1318 DECL_INITIAL(var_decl) = init;
1323 // If we take the address of a parameter, then we need to copy it into
1324 // the heap. We will access it as a local variable via an
1328 Function::copy_parm_to_heap(Gogo* gogo, Named_object* no, tree var_decl)
1330 if (var_decl == error_mark_node)
1331 return error_mark_node;
1332 go_assert(TREE_CODE(var_decl) == VAR_DECL);
1333 source_location loc = DECL_SOURCE_LOCATION(var_decl);
1335 std::string name = IDENTIFIER_POINTER(DECL_NAME(var_decl));
1337 tree id = get_identifier_from_string(name);
1339 tree type = TREE_TYPE(var_decl);
1340 go_assert(POINTER_TYPE_P(type));
1341 type = TREE_TYPE(type);
1343 tree parm_decl = build_decl(loc, PARM_DECL, id, type);
1344 DECL_CONTEXT(parm_decl) = current_function_decl;
1345 DECL_ARG_TYPE(parm_decl) = type;
1347 tree size = TYPE_SIZE_UNIT(type);
1348 tree space = gogo->allocate_memory(no->var_value()->type(), size, loc);
1349 space = save_expr(space);
1350 space = fold_convert(TREE_TYPE(var_decl), space);
1351 tree spaceref = build_fold_indirect_ref_loc(loc, space);
1352 TREE_THIS_NOTRAP(spaceref) = 1;
1353 tree init = build2(COMPOUND_EXPR, TREE_TYPE(space),
1354 build2(MODIFY_EXPR, void_type_node, spaceref, parm_decl),
1356 DECL_INITIAL(var_decl) = init;
1361 // Get a tree for function code.
1364 Function::build_tree(Gogo* gogo, Named_object* named_function)
1366 tree fndecl = this->fndecl_;
1367 go_assert(fndecl != NULL_TREE);
1369 tree params = NULL_TREE;
1372 tree declare_vars = NULL_TREE;
1373 for (Bindings::const_definitions_iterator p =
1374 this->block_->bindings()->begin_definitions();
1375 p != this->block_->bindings()->end_definitions();
1378 if ((*p)->is_variable() && (*p)->var_value()->is_parameter())
1380 Bvariable* bvar = (*p)->get_backend_variable(gogo, named_function);
1381 *pp = var_to_tree(bvar);
1383 // We always pass the receiver to a method as a pointer. If
1384 // the receiver is declared as a non-pointer type, then we
1385 // copy the value into a local variable.
1386 if ((*p)->var_value()->is_receiver()
1387 && (*p)->var_value()->type()->points_to() == NULL)
1389 tree parm_decl = this->make_receiver_parm_decl(gogo, *p, *pp);
1391 if (var != error_mark_node)
1393 go_assert(TREE_CODE(var) == VAR_DECL);
1394 DECL_CHAIN(var) = declare_vars;
1399 else if ((*p)->var_value()->is_in_heap())
1401 // If we take the address of a parameter, then we need
1402 // to copy it into the heap.
1403 tree parm_decl = this->copy_parm_to_heap(gogo, *p, *pp);
1405 if (var != error_mark_node)
1407 go_assert(TREE_CODE(var) == VAR_DECL);
1408 DECL_CHAIN(var) = declare_vars;
1414 if (*pp != error_mark_node)
1416 go_assert(TREE_CODE(*pp) == PARM_DECL);
1417 pp = &DECL_CHAIN(*pp);
1420 else if ((*p)->is_result_variable())
1422 Bvariable* bvar = (*p)->get_backend_variable(gogo, named_function);
1423 tree var_decl = var_to_tree(bvar);
1425 Type* type = (*p)->result_var_value()->type();
1427 if (!(*p)->result_var_value()->is_in_heap())
1429 Btype* btype = type->get_backend(gogo);
1430 init = expr_to_tree(gogo->backend()->zero_expression(btype));
1434 source_location loc = (*p)->location();
1435 tree type_tree = type_to_tree(type->get_backend(gogo));
1436 tree space = gogo->allocate_memory(type,
1437 TYPE_SIZE_UNIT(type_tree),
1439 tree ptr_type_tree = build_pointer_type(type_tree);
1440 init = fold_convert_loc(loc, ptr_type_tree, space);
1443 if (var_decl != error_mark_node)
1445 go_assert(TREE_CODE(var_decl) == VAR_DECL);
1446 DECL_INITIAL(var_decl) = init;
1447 DECL_CHAIN(var_decl) = declare_vars;
1448 declare_vars = var_decl;
1454 DECL_ARGUMENTS(fndecl) = params;
1456 if (this->block_ != NULL)
1458 go_assert(DECL_INITIAL(fndecl) == NULL_TREE);
1460 // Declare variables if necessary.
1461 tree bind = NULL_TREE;
1462 tree defer_init = NULL_TREE;
1463 if (declare_vars != NULL_TREE || this->defer_stack_ != NULL)
1465 tree block = make_node(BLOCK);
1466 BLOCK_SUPERCONTEXT(block) = fndecl;
1467 DECL_INITIAL(fndecl) = block;
1468 BLOCK_VARS(block) = declare_vars;
1469 TREE_USED(block) = 1;
1471 bind = build3(BIND_EXPR, void_type_node, BLOCK_VARS(block),
1473 TREE_SIDE_EFFECTS(bind) = 1;
1475 if (this->defer_stack_ != NULL)
1477 Translate_context dcontext(gogo, named_function, this->block_,
1478 tree_to_block(bind));
1479 Bstatement* bdi = this->defer_stack_->get_backend(&dcontext);
1480 defer_init = stat_to_tree(bdi);
1484 // Build the trees for all the statements in the function.
1485 Translate_context context(gogo, named_function, NULL, NULL);
1486 Bblock* bblock = this->block_->get_backend(&context);
1487 tree code = block_to_tree(bblock);
1489 tree init = NULL_TREE;
1490 tree except = NULL_TREE;
1491 tree fini = NULL_TREE;
1493 // Initialize variables if necessary.
1494 for (tree v = declare_vars; v != NULL_TREE; v = DECL_CHAIN(v))
1496 tree dv = build1(DECL_EXPR, void_type_node, v);
1497 SET_EXPR_LOCATION(dv, DECL_SOURCE_LOCATION(v));
1498 append_to_statement_list(dv, &init);
1501 // If we have a defer stack, initialize it at the start of a
1503 if (defer_init != NULL_TREE && defer_init != error_mark_node)
1505 SET_EXPR_LOCATION(defer_init, this->block_->start_location());
1506 append_to_statement_list(defer_init, &init);
1508 // Clean up the defer stack when we leave the function.
1509 this->build_defer_wrapper(gogo, named_function, &except, &fini);
1512 if (code != NULL_TREE && code != error_mark_node)
1514 if (init != NULL_TREE)
1515 code = build2(COMPOUND_EXPR, void_type_node, init, code);
1516 if (except != NULL_TREE)
1517 code = build2(TRY_CATCH_EXPR, void_type_node, code,
1518 build2(CATCH_EXPR, void_type_node, NULL, except));
1519 if (fini != NULL_TREE)
1520 code = build2(TRY_FINALLY_EXPR, void_type_node, code, fini);
1523 // Stick the code into the block we built for the receiver, if
1525 if (bind != NULL_TREE && code != NULL_TREE && code != error_mark_node)
1527 BIND_EXPR_BODY(bind) = code;
1531 DECL_SAVED_TREE(fndecl) = code;
1535 // Build the wrappers around function code needed if the function has
1536 // any defer statements. This sets *EXCEPT to an exception handler
1537 // and *FINI to a finally handler.
1540 Function::build_defer_wrapper(Gogo* gogo, Named_object* named_function,
1541 tree *except, tree *fini)
1543 source_location end_loc = this->block_->end_location();
1545 // Add an exception handler. This is used if a panic occurs. Its
1546 // purpose is to stop the stack unwinding if a deferred function
1547 // calls recover. There are more details in
1548 // libgo/runtime/go-unwind.c.
1550 tree stmt_list = NULL_TREE;
1552 Expression* call = Runtime::make_call(Runtime::CHECK_DEFER, end_loc, 1,
1553 this->defer_stack(end_loc));
1554 Translate_context context(gogo, named_function, NULL, NULL);
1555 tree call_tree = call->get_tree(&context);
1556 if (call_tree != error_mark_node)
1557 append_to_statement_list(call_tree, &stmt_list);
1559 tree retval = this->return_value(gogo, named_function, end_loc, &stmt_list);
1561 if (retval == NULL_TREE)
1564 set = fold_build2_loc(end_loc, MODIFY_EXPR, void_type_node,
1565 DECL_RESULT(this->fndecl_), retval);
1566 tree ret_stmt = fold_build1_loc(end_loc, RETURN_EXPR, void_type_node, set);
1567 append_to_statement_list(ret_stmt, &stmt_list);
1569 go_assert(*except == NULL_TREE);
1570 *except = stmt_list;
1572 // Add some finally code to run the defer functions. This is used
1573 // both in the normal case, when no panic occurs, and also if a
1574 // panic occurs to run any further defer functions. Of course, it
1575 // is possible for a defer function to call panic which should be
1576 // caught by another defer function. To handle that we use a loop.
1578 // try { __go_undefer(); } catch { __go_check_defer(); goto finish; }
1579 // if (return values are named) return named_vals;
1583 tree label = create_artificial_label(end_loc);
1584 tree define_label = fold_build1_loc(end_loc, LABEL_EXPR, void_type_node,
1586 append_to_statement_list(define_label, &stmt_list);
1588 call = Runtime::make_call(Runtime::UNDEFER, end_loc, 1,
1589 this->defer_stack(end_loc));
1590 tree undefer = call->get_tree(&context);
1592 call = Runtime::make_call(Runtime::CHECK_DEFER, end_loc, 1,
1593 this->defer_stack(end_loc));
1594 tree defer = call->get_tree(&context);
1596 if (undefer == error_mark_node || defer == error_mark_node)
1599 tree jump = fold_build1_loc(end_loc, GOTO_EXPR, void_type_node, label);
1600 tree catch_body = build2(COMPOUND_EXPR, void_type_node, defer, jump);
1601 catch_body = build2(CATCH_EXPR, void_type_node, NULL, catch_body);
1602 tree try_catch = build2(TRY_CATCH_EXPR, void_type_node, undefer, catch_body);
1604 append_to_statement_list(try_catch, &stmt_list);
1606 if (this->type_->results() != NULL
1607 && !this->type_->results()->empty()
1608 && !this->type_->results()->front().name().empty())
1610 // If the result variables are named, we need to return them
1611 // again, because they might have been changed by a defer
1613 retval = this->return_value(gogo, named_function, end_loc,
1615 set = fold_build2_loc(end_loc, MODIFY_EXPR, void_type_node,
1616 DECL_RESULT(this->fndecl_), retval);
1617 ret_stmt = fold_build1_loc(end_loc, RETURN_EXPR, void_type_node, set);
1618 append_to_statement_list(ret_stmt, &stmt_list);
1621 go_assert(*fini == NULL_TREE);
1625 // Return the value to assign to DECL_RESULT(this->fndecl_). This may
1626 // also add statements to STMT_LIST, which need to be executed before
1627 // the assignment. This is used for a return statement with no
1631 Function::return_value(Gogo* gogo, Named_object* named_function,
1632 source_location location, tree* stmt_list) const
1634 const Typed_identifier_list* results = this->type_->results();
1635 if (results == NULL || results->empty())
1638 go_assert(this->results_ != NULL);
1639 if (this->results_->size() != results->size())
1641 go_assert(saw_errors());
1642 return error_mark_node;
1646 if (results->size() == 1)
1649 this->results_->front()->get_backend_variable(gogo,
1651 tree ret = var_to_tree(bvar);
1652 if (this->results_->front()->result_var_value()->is_in_heap())
1653 ret = build_fold_indirect_ref_loc(location, ret);
1658 tree rettype = TREE_TYPE(DECL_RESULT(this->fndecl_));
1659 retval = create_tmp_var(rettype, "RESULT");
1660 tree field = TYPE_FIELDS(rettype);
1662 for (Typed_identifier_list::const_iterator pr = results->begin();
1663 pr != results->end();
1664 ++pr, ++index, field = DECL_CHAIN(field))
1666 go_assert(field != NULL);
1667 Named_object* no = (*this->results_)[index];
1668 Bvariable* bvar = no->get_backend_variable(gogo, named_function);
1669 tree val = var_to_tree(bvar);
1670 if (no->result_var_value()->is_in_heap())
1671 val = build_fold_indirect_ref_loc(location, val);
1672 tree set = fold_build2_loc(location, MODIFY_EXPR, void_type_node,
1673 build3(COMPONENT_REF, TREE_TYPE(field),
1674 retval, field, NULL_TREE),
1676 append_to_statement_list(set, stmt_list);
1682 // Return the integer type to use for a size.
1686 go_type_for_size(unsigned int bits, int unsignedp)
1692 name = unsignedp ? "uint8" : "int8";
1695 name = unsignedp ? "uint16" : "int16";
1698 name = unsignedp ? "uint32" : "int32";
1701 name = unsignedp ? "uint64" : "int64";
1704 if (bits == POINTER_SIZE && unsignedp)
1709 Type* type = Type::lookup_integer_type(name);
1710 return type_to_tree(type->get_backend(go_get_gogo()));
1713 // Return the type to use for a mode.
1717 go_type_for_mode(enum machine_mode mode, int unsignedp)
1719 // FIXME: This static_cast should be in machmode.h.
1720 enum mode_class mc = static_cast<enum mode_class>(GET_MODE_CLASS(mode));
1722 return go_type_for_size(GET_MODE_BITSIZE(mode), unsignedp);
1723 else if (mc == MODE_FLOAT)
1726 switch (GET_MODE_BITSIZE (mode))
1729 type = Type::lookup_float_type("float32");
1732 type = Type::lookup_float_type("float64");
1735 // We have to check for long double in order to support
1736 // i386 excess precision.
1737 if (mode == TYPE_MODE(long_double_type_node))
1738 return long_double_type_node;
1741 return type_to_tree(type->get_backend(go_get_gogo()));
1743 else if (mc == MODE_COMPLEX_FLOAT)
1746 switch (GET_MODE_BITSIZE (mode))
1749 type = Type::lookup_complex_type("complex64");
1752 type = Type::lookup_complex_type("complex128");
1755 // We have to check for long double in order to support
1756 // i386 excess precision.
1757 if (mode == TYPE_MODE(complex_long_double_type_node))
1758 return complex_long_double_type_node;
1761 return type_to_tree(type->get_backend(go_get_gogo()));
1767 // Return a tree which allocates SIZE bytes which will holds value of
1771 Gogo::allocate_memory(Type* type, tree size, source_location location)
1773 // If the package imports unsafe, then it may play games with
1774 // pointers that look like integers.
1775 if (this->imported_unsafe_ || type->has_pointer())
1777 static tree new_fndecl;
1778 return Gogo::call_builtin(&new_fndecl,
1788 static tree new_nopointers_fndecl;
1789 return Gogo::call_builtin(&new_nopointers_fndecl,
1791 "__go_new_nopointers",
1799 // Build a builtin struct with a list of fields. The name is
1800 // STRUCT_NAME. STRUCT_TYPE is NULL_TREE or an empty RECORD_TYPE
1801 // node; this exists so that the struct can have fields which point to
1802 // itself. If PTYPE is not NULL, store the result in *PTYPE. There
1803 // are NFIELDS fields. Each field is a name (a const char*) followed
1804 // by a type (a tree).
1807 Gogo::builtin_struct(tree* ptype, const char* struct_name, tree struct_type,
1810 if (ptype != NULL && *ptype != NULL_TREE)
1814 va_start(ap, nfields);
1816 tree fields = NULL_TREE;
1817 for (int i = 0; i < nfields; ++i)
1819 const char* field_name = va_arg(ap, const char*);
1820 tree type = va_arg(ap, tree);
1821 if (type == error_mark_node)
1824 *ptype = error_mark_node;
1825 return error_mark_node;
1827 tree field = build_decl(BUILTINS_LOCATION, FIELD_DECL,
1828 get_identifier(field_name), type);
1829 DECL_CHAIN(field) = fields;
1835 if (struct_type == NULL_TREE)
1836 struct_type = make_node(RECORD_TYPE);
1837 finish_builtin_struct(struct_type, struct_name, fields, NULL_TREE);
1841 go_preserve_from_gc(struct_type);
1842 *ptype = struct_type;
1848 // Return a type to use for pointer to const char for a string.
1851 Gogo::const_char_pointer_type_tree()
1854 if (type == NULL_TREE)
1856 tree const_char_type = build_qualified_type(unsigned_char_type_node,
1858 type = build_pointer_type(const_char_type);
1859 go_preserve_from_gc(type);
1864 // Return a tree for a string constant.
1867 Gogo::string_constant_tree(const std::string& val)
1869 tree index_type = build_index_type(size_int(val.length()));
1870 tree const_char_type = build_qualified_type(unsigned_char_type_node,
1872 tree string_type = build_array_type(const_char_type, index_type);
1873 string_type = build_variant_type_copy(string_type);
1874 TYPE_STRING_FLAG(string_type) = 1;
1875 tree string_val = build_string(val.length(), val.data());
1876 TREE_TYPE(string_val) = string_type;
1880 // Return a tree for a Go string constant.
1883 Gogo::go_string_constant_tree(const std::string& val)
1885 tree string_type = type_to_tree(Type::make_string_type()->get_backend(this));
1887 VEC(constructor_elt, gc)* init = VEC_alloc(constructor_elt, gc, 2);
1889 constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL);
1890 tree field = TYPE_FIELDS(string_type);
1891 go_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__data") == 0);
1893 tree str = Gogo::string_constant_tree(val);
1894 elt->value = fold_convert(TREE_TYPE(field),
1895 build_fold_addr_expr(str));
1897 elt = VEC_quick_push(constructor_elt, init, NULL);
1898 field = DECL_CHAIN(field);
1899 go_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__length") == 0);
1901 elt->value = build_int_cst_type(TREE_TYPE(field), val.length());
1903 tree constructor = build_constructor(string_type, init);
1904 TREE_READONLY(constructor) = 1;
1905 TREE_CONSTANT(constructor) = 1;
1910 // Return a tree for a pointer to a Go string constant. This is only
1911 // used for type descriptors, so we return a pointer to a constant
1915 Gogo::ptr_go_string_constant_tree(const std::string& val)
1917 tree pval = this->go_string_constant_tree(val);
1919 tree decl = build_decl(UNKNOWN_LOCATION, VAR_DECL,
1920 create_tmp_var_name("SP"), TREE_TYPE(pval));
1921 DECL_EXTERNAL(decl) = 0;
1922 TREE_PUBLIC(decl) = 0;
1923 TREE_USED(decl) = 1;
1924 TREE_READONLY(decl) = 1;
1925 TREE_CONSTANT(decl) = 1;
1926 TREE_STATIC(decl) = 1;
1927 DECL_ARTIFICIAL(decl) = 1;
1928 DECL_INITIAL(decl) = pval;
1929 rest_of_decl_compilation(decl, 1, 0);
1931 return build_fold_addr_expr(decl);
1934 // Build a constructor for a slice. SLICE_TYPE_TREE is the type of
1935 // the slice. VALUES is the value pointer and COUNT is the number of
1936 // entries. If CAPACITY is not NULL, it is the capacity; otherwise
1937 // the capacity and the count are the same.
1940 Gogo::slice_constructor(tree slice_type_tree, tree values, tree count,
1943 go_assert(TREE_CODE(slice_type_tree) == RECORD_TYPE);
1945 VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3);
1947 tree field = TYPE_FIELDS(slice_type_tree);
1948 go_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__values") == 0);
1949 constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL);
1951 go_assert(TYPE_MAIN_VARIANT(TREE_TYPE(field))
1952 == TYPE_MAIN_VARIANT(TREE_TYPE(values)));
1953 elt->value = values;
1955 count = fold_convert(sizetype, count);
1956 if (capacity == NULL_TREE)
1958 count = save_expr(count);
1962 field = DECL_CHAIN(field);
1963 go_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__count") == 0);
1964 elt = VEC_quick_push(constructor_elt, init, NULL);
1966 elt->value = fold_convert(TREE_TYPE(field), count);
1968 field = DECL_CHAIN(field);
1969 go_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__capacity") == 0);
1970 elt = VEC_quick_push(constructor_elt, init, NULL);
1972 elt->value = fold_convert(TREE_TYPE(field), capacity);
1974 return build_constructor(slice_type_tree, init);
1977 // Build an interface method table for a type: a list of function
1978 // pointers, one for each interface method. This is used for
1982 Gogo::interface_method_table_for_type(const Interface_type* interface,
1986 const Typed_identifier_list* interface_methods = interface->methods();
1987 go_assert(!interface_methods->empty());
1989 std::string mangled_name = ((is_pointer ? "__go_pimt__" : "__go_imt_")
1990 + interface->mangled_name(this)
1992 + type->mangled_name(this));
1994 tree id = get_identifier_from_string(mangled_name);
1996 // See whether this interface has any hidden methods.
1997 bool has_hidden_methods = false;
1998 for (Typed_identifier_list::const_iterator p = interface_methods->begin();
1999 p != interface_methods->end();
2002 if (Gogo::is_hidden_name(p->name()))
2004 has_hidden_methods = true;
2009 // We already know that the named type is convertible to the
2010 // interface. If the interface has hidden methods, and the named
2011 // type is defined in a different package, then the interface
2012 // conversion table will be defined by that other package.
2013 if (has_hidden_methods && type->named_object()->package() != NULL)
2015 tree array_type = build_array_type(const_ptr_type_node, NULL);
2016 tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, id, array_type);
2017 TREE_READONLY(decl) = 1;
2018 TREE_CONSTANT(decl) = 1;
2019 TREE_PUBLIC(decl) = 1;
2020 DECL_EXTERNAL(decl) = 1;
2021 go_preserve_from_gc(decl);
2025 size_t count = interface_methods->size();
2026 VEC(constructor_elt, gc)* pointers = VEC_alloc(constructor_elt, gc,
2029 // The first element is the type descriptor.
2030 constructor_elt* elt = VEC_quick_push(constructor_elt, pointers, NULL);
2031 elt->index = size_zero_node;
2036 td_type = Type::make_pointer_type(type);
2037 tree tdp = td_type->type_descriptor_pointer(this, BUILTINS_LOCATION);
2038 elt->value = fold_convert(const_ptr_type_node, tdp);
2041 for (Typed_identifier_list::const_iterator p = interface_methods->begin();
2042 p != interface_methods->end();
2046 Method* m = type->method_function(p->name(), &is_ambiguous);
2047 go_assert(m != NULL);
2049 Named_object* no = m->named_object();
2051 tree fnid = no->get_id(this);
2054 if (no->is_function())
2055 fndecl = no->func_value()->get_or_make_decl(this, no, fnid);
2056 else if (no->is_function_declaration())
2057 fndecl = no->func_declaration_value()->get_or_make_decl(this, no,
2061 fndecl = build_fold_addr_expr(fndecl);
2063 elt = VEC_quick_push(constructor_elt, pointers, NULL);
2064 elt->index = size_int(i);
2065 elt->value = fold_convert(const_ptr_type_node, fndecl);
2067 go_assert(i == count + 1);
2069 tree array_type = build_array_type(const_ptr_type_node,
2070 build_index_type(size_int(count)));
2071 tree constructor = build_constructor(array_type, pointers);
2073 tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, id, array_type);
2074 TREE_STATIC(decl) = 1;
2075 TREE_USED(decl) = 1;
2076 TREE_READONLY(decl) = 1;
2077 TREE_CONSTANT(decl) = 1;
2078 DECL_INITIAL(decl) = constructor;
2080 // If the interface type has hidden methods, then this is the only
2081 // definition of the table. Otherwise it is a comdat table which
2082 // may be defined in multiple packages.
2083 if (has_hidden_methods)
2084 TREE_PUBLIC(decl) = 1;
2087 make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl));
2088 resolve_unique_section(decl, 1, 0);
2091 rest_of_decl_compilation(decl, 1, 0);
2093 go_preserve_from_gc(decl);
2098 // Mark a function as a builtin library function.
2101 Gogo::mark_fndecl_as_builtin_library(tree fndecl)
2103 DECL_EXTERNAL(fndecl) = 1;
2104 TREE_PUBLIC(fndecl) = 1;
2105 DECL_ARTIFICIAL(fndecl) = 1;
2106 TREE_NOTHROW(fndecl) = 1;
2107 DECL_VISIBILITY(fndecl) = VISIBILITY_DEFAULT;
2108 DECL_VISIBILITY_SPECIFIED(fndecl) = 1;
2111 // Build a call to a builtin function.
2114 Gogo::call_builtin(tree* pdecl, source_location location, const char* name,
2115 int nargs, tree rettype, ...)
2117 if (rettype == error_mark_node)
2118 return error_mark_node;
2120 tree* types = new tree[nargs];
2121 tree* args = new tree[nargs];
2124 va_start(ap, rettype);
2125 for (int i = 0; i < nargs; ++i)
2127 types[i] = va_arg(ap, tree);
2128 args[i] = va_arg(ap, tree);
2129 if (types[i] == error_mark_node || args[i] == error_mark_node)
2133 return error_mark_node;
2138 if (*pdecl == NULL_TREE)
2140 tree fnid = get_identifier(name);
2142 tree argtypes = NULL_TREE;
2143 tree* pp = &argtypes;
2144 for (int i = 0; i < nargs; ++i)
2146 *pp = tree_cons(NULL_TREE, types[i], NULL_TREE);
2147 pp = &TREE_CHAIN(*pp);
2149 *pp = void_list_node;
2151 tree fntype = build_function_type(rettype, argtypes);
2153 *pdecl = build_decl(BUILTINS_LOCATION, FUNCTION_DECL, fnid, fntype);
2154 Gogo::mark_fndecl_as_builtin_library(*pdecl);
2155 go_preserve_from_gc(*pdecl);
2158 tree fnptr = build_fold_addr_expr(*pdecl);
2159 if (CAN_HAVE_LOCATION_P(fnptr))
2160 SET_EXPR_LOCATION(fnptr, location);
2162 tree ret = build_call_array(rettype, fnptr, nargs, args);
2163 SET_EXPR_LOCATION(ret, location);
2171 // Build a call to the runtime error function.
2174 Gogo::runtime_error(int code, source_location location)
2176 static tree runtime_error_fndecl;
2177 tree ret = Gogo::call_builtin(&runtime_error_fndecl,
2179 "__go_runtime_error",
2183 build_int_cst(integer_type_node, code));
2184 if (ret == error_mark_node)
2185 return error_mark_node;
2186 // The runtime error function panics and does not return.
2187 TREE_NOTHROW(runtime_error_fndecl) = 0;
2188 TREE_THIS_VOLATILE(runtime_error_fndecl) = 1;
2192 // Return a tree for receiving a value of type TYPE_TREE on CHANNEL.
2193 // This does a blocking receive and returns the value read from the
2194 // channel. If FOR_SELECT is true, this is being done because it was
2195 // chosen in a select statement.
2198 Gogo::receive_from_channel(tree type_tree, tree channel, bool for_select,
2199 source_location location)
2201 if (type_tree == error_mark_node || channel == error_mark_node)
2202 return error_mark_node;
2204 if (int_size_in_bytes(type_tree) <= 8
2205 && !AGGREGATE_TYPE_P(type_tree)
2206 && !FLOAT_TYPE_P(type_tree))
2208 static tree receive_small_fndecl;
2209 tree call = Gogo::call_builtin(&receive_small_fndecl,
2211 "__go_receive_small",
2219 : boolean_false_node));
2220 if (call == error_mark_node)
2221 return error_mark_node;
2222 // This can panic if there are too many operations on a closed
2224 TREE_NOTHROW(receive_small_fndecl) = 0;
2225 int bitsize = GET_MODE_BITSIZE(TYPE_MODE(type_tree));
2226 tree int_type_tree = go_type_for_size(bitsize, 1);
2227 return fold_convert_loc(location, type_tree,
2228 fold_convert_loc(location, int_type_tree,
2233 tree tmp = create_tmp_var(type_tree, get_name(type_tree));
2234 DECL_IGNORED_P(tmp) = 0;
2235 TREE_ADDRESSABLE(tmp) = 1;
2236 tree make_tmp = build1(DECL_EXPR, void_type_node, tmp);
2237 SET_EXPR_LOCATION(make_tmp, location);
2238 tree tmpaddr = build_fold_addr_expr(tmp);
2239 tmpaddr = fold_convert(ptr_type_node, tmpaddr);
2240 static tree receive_big_fndecl;
2241 tree call = Gogo::call_builtin(&receive_big_fndecl,
2253 : boolean_false_node));
2254 if (call == error_mark_node)
2255 return error_mark_node;
2256 // This can panic if there are too many operations on a closed
2258 TREE_NOTHROW(receive_big_fndecl) = 0;
2259 return build2(COMPOUND_EXPR, type_tree, make_tmp,
2260 build2(COMPOUND_EXPR, type_tree, call, tmp));
2264 // Return the type of a function trampoline. This is like
2265 // get_trampoline_type in tree-nested.c.
2268 Gogo::trampoline_type_tree()
2270 static tree type_tree;
2271 if (type_tree == NULL_TREE)
2275 go_trampoline_info(&size, &align);
2276 tree t = build_index_type(build_int_cst(integer_type_node, size - 1));
2277 t = build_array_type(char_type_node, t);
2279 type_tree = Gogo::builtin_struct(NULL, "__go_trampoline", NULL_TREE, 1,
2281 t = TYPE_FIELDS(type_tree);
2282 DECL_ALIGN(t) = align;
2283 DECL_USER_ALIGN(t) = 1;
2285 go_preserve_from_gc(type_tree);
2290 // Make a trampoline which calls FNADDR passing CLOSURE.
2293 Gogo::make_trampoline(tree fnaddr, tree closure, source_location location)
2295 tree trampoline_type = Gogo::trampoline_type_tree();
2296 tree trampoline_size = TYPE_SIZE_UNIT(trampoline_type);
2298 closure = save_expr(closure);
2300 // We allocate the trampoline using a special function which will
2301 // mark it as executable.
2302 static tree trampoline_fndecl;
2303 tree x = Gogo::call_builtin(&trampoline_fndecl,
2305 "__go_allocate_trampoline",
2311 fold_convert_loc(location, ptr_type_node,
2313 if (x == error_mark_node)
2314 return error_mark_node;
2318 // Initialize the trampoline.
2319 tree ini = build_call_expr(implicit_built_in_decls[BUILT_IN_INIT_TRAMPOLINE],
2320 3, x, fnaddr, closure);
2322 // On some targets the trampoline address needs to be adjusted. For
2323 // example, when compiling in Thumb mode on the ARM, the address
2324 // needs to have the low bit set.
2325 x = build_call_expr(implicit_built_in_decls[BUILT_IN_ADJUST_TRAMPOLINE],
2327 x = fold_convert(TREE_TYPE(fnaddr), x);
2329 return build2(COMPOUND_EXPR, TREE_TYPE(x), ini, x);