// go-gcc.cc -- Go frontend to gcc IR. // Copyright (C) 2011-2017 Free Software Foundation, Inc. // Contributed by Ian Lance Taylor, Google. // This file is part of GCC. // GCC is free software; you can redistribute it and/or modify it under // the terms of the GNU General Public License as published by the Free // Software Foundation; either version 3, or (at your option) any later // version. // GCC is distributed in the hope that it will be useful, but WITHOUT ANY // WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License // for more details. // You should have received a copy of the GNU General Public License // along with GCC; see the file COPYING3. If not see // . #include "go-system.h" // This has to be included outside of extern "C", so we have to // include it here before tree.h includes it later. #include #include "tree.h" #include "fold-const.h" #include "stringpool.h" #include "stor-layout.h" #include "varasm.h" #include "tree-iterator.h" #include "tm.h" #include "function.h" #include "cgraph.h" #include "convert.h" #include "gimple-expr.h" #include "gimplify.h" #include "langhooks.h" #include "toplev.h" #include "output.h" #include "realmpfr.h" #include "builtins.h" #include "go-c.h" #include "go-gcc.h" #include "gogo.h" #include "backend.h" // A class wrapping a tree. class Gcc_tree { public: Gcc_tree(tree t) : t_(t) { } tree get_tree() const { return this->t_; } void set_tree(tree t) { this->t_ = t; } private: tree t_; }; // In gcc, types, expressions, and statements are all trees. class Btype : public Gcc_tree { public: Btype(tree t) : Gcc_tree(t) { } }; class Bexpression : public Gcc_tree { public: Bexpression(tree t) : Gcc_tree(t) { } }; class Bstatement : public Gcc_tree { public: Bstatement(tree t) : Gcc_tree(t) { } }; class Bfunction : public Gcc_tree { public: Bfunction(tree t) : Gcc_tree(t) { } }; class Bblock : public Gcc_tree { public: Bblock(tree t) : Gcc_tree(t) { } }; class Blabel : public Gcc_tree { public: Blabel(tree t) : Gcc_tree(t) { } }; // Bvariable is a bit more complicated, because of zero-sized types. // The GNU linker does not permit dynamic variables with zero size. // When we see such a variable, we generate a version of the type with // non-zero size. However, when referring to the global variable, we // want an expression of zero size; otherwise, if, say, the global // variable is passed to a function, we will be passing a // non-zero-sized value to a zero-sized value, which can lead to a // miscompilation. class Bvariable { public: Bvariable(tree t) : t_(t), orig_type_(NULL) { } Bvariable(tree t, tree orig_type) : t_(t), orig_type_(orig_type) { } // Get the tree for use as an expression. tree get_tree(Location) const; // Get the actual decl; tree get_decl() const { return this->t_; } private: tree t_; tree orig_type_; }; // Get the tree of a variable for use as an expression. If this is a // zero-sized global, create an expression that refers to the decl but // has zero size. tree Bvariable::get_tree(Location location) const { if (this->orig_type_ == NULL || this->t_ == error_mark_node || TREE_TYPE(this->t_) == this->orig_type_) return this->t_; // Return *(orig_type*)&decl. */ tree t = build_fold_addr_expr_loc(location.gcc_location(), this->t_); t = fold_build1_loc(location.gcc_location(), NOP_EXPR, build_pointer_type(this->orig_type_), t); return build_fold_indirect_ref_loc(location.gcc_location(), t); } // This file implements the interface between the Go frontend proper // and the gcc IR. This implements specific instantiations of // abstract classes defined by the Go frontend proper. The Go // frontend proper class methods of these classes to generate the // backend representation. class Gcc_backend : public Backend { public: Gcc_backend(); // Types. Btype* error_type() { return this->make_type(error_mark_node); } Btype* void_type() { return this->make_type(void_type_node); } Btype* bool_type() { return this->make_type(boolean_type_node); } Btype* integer_type(bool, int); Btype* float_type(int); Btype* complex_type(int); Btype* pointer_type(Btype*); Btype* function_type(const Btyped_identifier&, const std::vector&, const std::vector&, Btype*, const Location); Btype* struct_type(const std::vector&); Btype* array_type(Btype*, Bexpression*); Btype* placeholder_pointer_type(const std::string&, Location, bool); bool set_placeholder_pointer_type(Btype*, Btype*); bool set_placeholder_function_type(Btype*, Btype*); Btype* placeholder_struct_type(const std::string&, Location); bool set_placeholder_struct_type(Btype* placeholder, const std::vector&); Btype* placeholder_array_type(const std::string&, Location); bool set_placeholder_array_type(Btype*, Btype*, Bexpression*); Btype* named_type(const std::string&, Btype*, Location); Btype* circular_pointer_type(Btype*, bool); bool is_circular_pointer_type(Btype*); int64_t type_size(Btype*); int64_t type_alignment(Btype*); int64_t type_field_alignment(Btype*); int64_t type_field_offset(Btype*, size_t index); // Expressions. Bexpression* zero_expression(Btype*); Bexpression* error_expression() { return this->make_expression(error_mark_node); } Bexpression* nil_pointer_expression() { return this->make_expression(null_pointer_node); } Bexpression* var_expression(Bvariable* var, Varexpr_context, Location); Bexpression* indirect_expression(Btype*, Bexpression* expr, bool known_valid, Location); Bexpression* named_constant_expression(Btype* btype, const std::string& name, Bexpression* val, Location); Bexpression* integer_constant_expression(Btype* btype, mpz_t val); Bexpression* float_constant_expression(Btype* btype, mpfr_t val); Bexpression* complex_constant_expression(Btype* btype, mpc_t val); Bexpression* string_constant_expression(const std::string& val); Bexpression* boolean_constant_expression(bool val); Bexpression* real_part_expression(Bexpression* bcomplex, Location); Bexpression* imag_part_expression(Bexpression* bcomplex, Location); Bexpression* complex_expression(Bexpression* breal, Bexpression* bimag, Location); Bexpression* convert_expression(Btype* type, Bexpression* expr, Location); Bexpression* function_code_expression(Bfunction*, Location); Bexpression* address_expression(Bexpression*, Location); Bexpression* struct_field_expression(Bexpression*, size_t, Location); Bexpression* compound_expression(Bstatement*, Bexpression*, Location); Bexpression* conditional_expression(Bfunction*, Btype*, Bexpression*, Bexpression*, Bexpression*, Location); Bexpression* unary_expression(Operator, Bexpression*, Location); Bexpression* binary_expression(Operator, Bexpression*, Bexpression*, Location); Bexpression* constructor_expression(Btype*, const std::vector&, Location); Bexpression* array_constructor_expression(Btype*, const std::vector&, const std::vector&, Location); Bexpression* pointer_offset_expression(Bexpression* base, Bexpression* offset, Location); Bexpression* array_index_expression(Bexpression* array, Bexpression* index, Location); Bexpression* call_expression(Bexpression* fn, const std::vector& args, Bexpression* static_chain, Location); Bexpression* stack_allocation_expression(int64_t size, Location); // Statements. Bstatement* error_statement() { return this->make_statement(error_mark_node); } Bstatement* expression_statement(Bfunction*, Bexpression*); Bstatement* init_statement(Bfunction*, Bvariable* var, Bexpression* init); Bstatement* assignment_statement(Bfunction*, Bexpression* lhs, Bexpression* rhs, Location); Bstatement* return_statement(Bfunction*, const std::vector&, Location); Bstatement* if_statement(Bfunction*, Bexpression* condition, Bblock* then_block, Bblock* else_block, Location); Bstatement* switch_statement(Bfunction* function, Bexpression* value, const std::vector >& cases, const std::vector& statements, Location); Bstatement* compound_statement(Bstatement*, Bstatement*); Bstatement* statement_list(const std::vector&); Bstatement* exception_handler_statement(Bstatement* bstat, Bstatement* except_stmt, Bstatement* finally_stmt, Location); // Blocks. Bblock* block(Bfunction*, Bblock*, const std::vector&, Location, Location); void block_add_statements(Bblock*, const std::vector&); Bstatement* block_statement(Bblock*); // Variables. Bvariable* error_variable() { return new Bvariable(error_mark_node); } Bvariable* global_variable(const std::string& var_name, const std::string& asm_name, Btype* btype, bool is_external, bool is_hidden, bool in_unique_section, Location location); void global_variable_set_init(Bvariable*, Bexpression*); Bvariable* local_variable(Bfunction*, const std::string&, Btype*, bool, Location); Bvariable* parameter_variable(Bfunction*, const std::string&, Btype*, bool, Location); Bvariable* static_chain_variable(Bfunction*, const std::string&, Btype*, Location); Bvariable* temporary_variable(Bfunction*, Bblock*, Btype*, Bexpression*, bool, Location, Bstatement**); Bvariable* implicit_variable(const std::string&, const std::string&, Btype*, bool, bool, bool, int64_t); void implicit_variable_set_init(Bvariable*, const std::string&, Btype*, bool, bool, bool, Bexpression*); Bvariable* implicit_variable_reference(const std::string&, const std::string&, Btype*); Bvariable* immutable_struct(const std::string&, const std::string&, bool, bool, Btype*, Location); void immutable_struct_set_init(Bvariable*, const std::string&, bool, bool, Btype*, Location, Bexpression*); Bvariable* immutable_struct_reference(const std::string&, const std::string&, Btype*, Location); // Labels. Blabel* label(Bfunction*, const std::string& name, Location); Bstatement* label_definition_statement(Blabel*); Bstatement* goto_statement(Blabel*, Location); Bexpression* label_address(Blabel*, Location); // Functions. Bfunction* error_function() { return this->make_function(error_mark_node); } Bfunction* function(Btype* fntype, const std::string& name, const std::string& asm_name, bool is_visible, bool is_declaration, bool is_inlinable, bool disable_split_stack, bool in_unique_section, Location); Bstatement* function_defer_statement(Bfunction* function, Bexpression* undefer, Bexpression* defer, Location); bool function_set_parameters(Bfunction* function, const std::vector&); bool function_set_body(Bfunction* function, Bstatement* code_stmt); Bfunction* lookup_builtin(const std::string&); void write_global_definitions(const std::vector&, const std::vector&, const std::vector&, const std::vector&); private: // Make a Bexpression from a tree. Bexpression* make_expression(tree t) { return new Bexpression(t); } // Make a Bstatement from a tree. Bstatement* make_statement(tree t) { return new Bstatement(t); } // Make a Btype from a tree. Btype* make_type(tree t) { return new Btype(t); } Bfunction* make_function(tree t) { return new Bfunction(t); } Btype* fill_in_struct(Btype*, const std::vector&); Btype* fill_in_array(Btype*, Btype*, Bexpression*); tree non_zero_size_type(tree); private: void define_builtin(built_in_function bcode, const char* name, const char* libname, tree fntype, bool const_p, bool noreturn_p); // A mapping of the GCC built-ins exposed to GCCGo. std::map builtin_functions_; }; // A helper function to create a GCC identifier from a C++ string. static inline tree get_identifier_from_string(const std::string& str) { return get_identifier_with_length(str.data(), str.length()); } // Define the built-in functions that are exposed to GCCGo. Gcc_backend::Gcc_backend() { /* We need to define the fetch_and_add functions, since we use them for ++ and --. */ tree t = this->integer_type(true, BITS_PER_UNIT)->get_tree(); tree p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); this->define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_1, "__sync_fetch_and_add_1", NULL, build_function_type_list(t, p, t, NULL_TREE), false, false); t = this->integer_type(true, BITS_PER_UNIT * 2)->get_tree(); p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); this->define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_2, "__sync_fetch_and_add_2", NULL, build_function_type_list(t, p, t, NULL_TREE), false, false); t = this->integer_type(true, BITS_PER_UNIT * 4)->get_tree(); p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); this->define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_4, "__sync_fetch_and_add_4", NULL, build_function_type_list(t, p, t, NULL_TREE), false, false); t = this->integer_type(true, BITS_PER_UNIT * 8)->get_tree(); p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); this->define_builtin(BUILT_IN_SYNC_ADD_AND_FETCH_8, "__sync_fetch_and_add_8", NULL, build_function_type_list(t, p, t, NULL_TREE), false, false); // We use __builtin_expect for magic import functions. this->define_builtin(BUILT_IN_EXPECT, "__builtin_expect", NULL, build_function_type_list(long_integer_type_node, long_integer_type_node, long_integer_type_node, NULL_TREE), true, false); // We use __builtin_memcmp for struct comparisons. this->define_builtin(BUILT_IN_MEMCMP, "__builtin_memcmp", "memcmp", build_function_type_list(integer_type_node, const_ptr_type_node, const_ptr_type_node, size_type_node, NULL_TREE), false, false); // Used by runtime/internal/sys. this->define_builtin(BUILT_IN_CTZ, "__builtin_ctz", "ctz", build_function_type_list(integer_type_node, unsigned_type_node, NULL_TREE), true, false); this->define_builtin(BUILT_IN_CTZLL, "__builtin_ctzll", "ctzll", build_function_type_list(integer_type_node, long_long_unsigned_type_node, NULL_TREE), true, false); this->define_builtin(BUILT_IN_BSWAP32, "__builtin_bswap32", "bswap32", build_function_type_list(uint32_type_node, uint32_type_node, NULL_TREE), true, false); this->define_builtin(BUILT_IN_BSWAP64, "__builtin_bswap64", "bswap64", build_function_type_list(uint64_type_node, uint64_type_node, NULL_TREE), true, false); // We provide some functions for the math library. tree math_function_type = build_function_type_list(double_type_node, double_type_node, NULL_TREE); tree math_function_type_long = build_function_type_list(long_double_type_node, long_double_type_node, long_double_type_node, NULL_TREE); tree math_function_type_two = build_function_type_list(double_type_node, double_type_node, double_type_node, NULL_TREE); tree math_function_type_long_two = build_function_type_list(long_double_type_node, long_double_type_node, long_double_type_node, NULL_TREE); this->define_builtin(BUILT_IN_ACOS, "__builtin_acos", "acos", math_function_type, true, false); this->define_builtin(BUILT_IN_ACOSL, "__builtin_acosl", "acosl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_ASIN, "__builtin_asin", "asin", math_function_type, true, false); this->define_builtin(BUILT_IN_ASINL, "__builtin_asinl", "asinl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_ATAN, "__builtin_atan", "atan", math_function_type, true, false); this->define_builtin(BUILT_IN_ATANL, "__builtin_atanl", "atanl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_ATAN2, "__builtin_atan2", "atan2", math_function_type_two, true, false); this->define_builtin(BUILT_IN_ATAN2L, "__builtin_atan2l", "atan2l", math_function_type_long_two, true, false); this->define_builtin(BUILT_IN_CEIL, "__builtin_ceil", "ceil", math_function_type, true, false); this->define_builtin(BUILT_IN_CEILL, "__builtin_ceill", "ceill", math_function_type_long, true, false); this->define_builtin(BUILT_IN_COS, "__builtin_cos", "cos", math_function_type, true, false); this->define_builtin(BUILT_IN_COSL, "__builtin_cosl", "cosl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_EXP, "__builtin_exp", "exp", math_function_type, true, false); this->define_builtin(BUILT_IN_EXPL, "__builtin_expl", "expl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_EXPM1, "__builtin_expm1", "expm1", math_function_type, true, false); this->define_builtin(BUILT_IN_EXPM1L, "__builtin_expm1l", "expm1l", math_function_type_long, true, false); this->define_builtin(BUILT_IN_FABS, "__builtin_fabs", "fabs", math_function_type, true, false); this->define_builtin(BUILT_IN_FABSL, "__builtin_fabsl", "fabsl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_FLOOR, "__builtin_floor", "floor", math_function_type, true, false); this->define_builtin(BUILT_IN_FLOORL, "__builtin_floorl", "floorl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_FMOD, "__builtin_fmod", "fmod", math_function_type_two, true, false); this->define_builtin(BUILT_IN_FMODL, "__builtin_fmodl", "fmodl", math_function_type_long_two, true, false); this->define_builtin(BUILT_IN_LDEXP, "__builtin_ldexp", "ldexp", build_function_type_list(double_type_node, double_type_node, integer_type_node, NULL_TREE), true, false); this->define_builtin(BUILT_IN_LDEXPL, "__builtin_ldexpl", "ldexpl", build_function_type_list(long_double_type_node, long_double_type_node, integer_type_node, NULL_TREE), true, false); this->define_builtin(BUILT_IN_LOG, "__builtin_log", "log", math_function_type, true, false); this->define_builtin(BUILT_IN_LOGL, "__builtin_logl", "logl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_LOG1P, "__builtin_log1p", "log1p", math_function_type, true, false); this->define_builtin(BUILT_IN_LOG1PL, "__builtin_log1pl", "log1pl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_LOG10, "__builtin_log10", "log10", math_function_type, true, false); this->define_builtin(BUILT_IN_LOG10L, "__builtin_log10l", "log10l", math_function_type_long, true, false); this->define_builtin(BUILT_IN_LOG2, "__builtin_log2", "log2", math_function_type, true, false); this->define_builtin(BUILT_IN_LOG2L, "__builtin_log2l", "log2l", math_function_type_long, true, false); this->define_builtin(BUILT_IN_SIN, "__builtin_sin", "sin", math_function_type, true, false); this->define_builtin(BUILT_IN_SINL, "__builtin_sinl", "sinl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_SQRT, "__builtin_sqrt", "sqrt", math_function_type, true, false); this->define_builtin(BUILT_IN_SQRTL, "__builtin_sqrtl", "sqrtl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_TAN, "__builtin_tan", "tan", math_function_type, true, false); this->define_builtin(BUILT_IN_TANL, "__builtin_tanl", "tanl", math_function_type_long, true, false); this->define_builtin(BUILT_IN_TRUNC, "__builtin_trunc", "trunc", math_function_type, true, false); this->define_builtin(BUILT_IN_TRUNCL, "__builtin_truncl", "truncl", math_function_type_long, true, false); // We use __builtin_return_address in the thunk we build for // functions which call recover, and for runtime.getcallerpc. t = build_function_type_list(ptr_type_node, unsigned_type_node, NULL_TREE); this->define_builtin(BUILT_IN_RETURN_ADDRESS, "__builtin_return_address", NULL, t, false, false); // The runtime calls __builtin_frame_address for runtime.getcallersp. this->define_builtin(BUILT_IN_FRAME_ADDRESS, "__builtin_frame_address", NULL, t, false, false); // The runtime calls __builtin_extract_return_addr when recording // the address to which a function returns. this->define_builtin(BUILT_IN_EXTRACT_RETURN_ADDR, "__builtin_extract_return_addr", NULL, build_function_type_list(ptr_type_node, ptr_type_node, NULL_TREE), false, false); // The compiler uses __builtin_trap for some exception handling // cases. this->define_builtin(BUILT_IN_TRAP, "__builtin_trap", NULL, build_function_type(void_type_node, void_list_node), false, true); } // Get an unnamed integer type. Btype* Gcc_backend::integer_type(bool is_unsigned, int bits) { tree type; if (is_unsigned) { if (bits == INT_TYPE_SIZE) type = unsigned_type_node; else if (bits == CHAR_TYPE_SIZE) type = unsigned_char_type_node; else if (bits == SHORT_TYPE_SIZE) type = short_unsigned_type_node; else if (bits == LONG_TYPE_SIZE) type = long_unsigned_type_node; else if (bits == LONG_LONG_TYPE_SIZE) type = long_long_unsigned_type_node; else type = make_unsigned_type(bits); } else { if (bits == INT_TYPE_SIZE) type = integer_type_node; else if (bits == CHAR_TYPE_SIZE) type = signed_char_type_node; else if (bits == SHORT_TYPE_SIZE) type = short_integer_type_node; else if (bits == LONG_TYPE_SIZE) type = long_integer_type_node; else if (bits == LONG_LONG_TYPE_SIZE) type = long_long_integer_type_node; else type = make_signed_type(bits); } return this->make_type(type); } // Get an unnamed float type. Btype* Gcc_backend::float_type(int bits) { tree type; if (bits == FLOAT_TYPE_SIZE) type = float_type_node; else if (bits == DOUBLE_TYPE_SIZE) type = double_type_node; else if (bits == LONG_DOUBLE_TYPE_SIZE) type = long_double_type_node; else { type = make_node(REAL_TYPE); TYPE_PRECISION(type) = bits; layout_type(type); } return this->make_type(type); } // Get an unnamed complex type. Btype* Gcc_backend::complex_type(int bits) { tree type; if (bits == FLOAT_TYPE_SIZE * 2) type = complex_float_type_node; else if (bits == DOUBLE_TYPE_SIZE * 2) type = complex_double_type_node; else if (bits == LONG_DOUBLE_TYPE_SIZE * 2) type = complex_long_double_type_node; else { type = make_node(REAL_TYPE); TYPE_PRECISION(type) = bits / 2; layout_type(type); type = build_complex_type(type); } return this->make_type(type); } // Get a pointer type. Btype* Gcc_backend::pointer_type(Btype* to_type) { tree to_type_tree = to_type->get_tree(); if (to_type_tree == error_mark_node) return this->error_type(); tree type = build_pointer_type(to_type_tree); return this->make_type(type); } // Make a function type. Btype* Gcc_backend::function_type(const Btyped_identifier& receiver, const std::vector& parameters, const std::vector& results, Btype* result_struct, Location) { tree args = NULL_TREE; tree* pp = &args; if (receiver.btype != NULL) { tree t = receiver.btype->get_tree(); if (t == error_mark_node) return this->error_type(); *pp = tree_cons(NULL_TREE, t, NULL_TREE); pp = &TREE_CHAIN(*pp); } for (std::vector::const_iterator p = parameters.begin(); p != parameters.end(); ++p) { tree t = p->btype->get_tree(); if (t == error_mark_node) return this->error_type(); *pp = tree_cons(NULL_TREE, t, NULL_TREE); pp = &TREE_CHAIN(*pp); } // Varargs is handled entirely at the Go level. When converted to // GENERIC functions are not varargs. *pp = void_list_node; tree result; if (results.empty()) result = void_type_node; else if (results.size() == 1) result = results.front().btype->get_tree(); else { gcc_assert(result_struct != NULL); result = result_struct->get_tree(); } if (result == error_mark_node) return this->error_type(); // The libffi library can not represent a zero-sized object. To // avoid causing confusion on 32-bit SPARC, we treat a function that // returns a zero-sized value as returning void. That should do no // harm since there is no actual value to be returned. See // https://gcc.gnu.org/PR72814 for details. if (result != void_type_node && int_size_in_bytes(result) == 0) result = void_type_node; tree fntype = build_function_type(result, args); if (fntype == error_mark_node) return this->error_type(); return this->make_type(build_pointer_type(fntype)); } // Make a struct type. Btype* Gcc_backend::struct_type(const std::vector& fields) { return this->fill_in_struct(this->make_type(make_node(RECORD_TYPE)), fields); } // Fill in the fields of a struct type. Btype* Gcc_backend::fill_in_struct(Btype* fill, const std::vector& fields) { tree fill_tree = fill->get_tree(); tree field_trees = NULL_TREE; tree* pp = &field_trees; for (std::vector::const_iterator p = fields.begin(); p != fields.end(); ++p) { tree name_tree = get_identifier_from_string(p->name); tree type_tree = p->btype->get_tree(); if (type_tree == error_mark_node) return this->error_type(); tree field = build_decl(p->location.gcc_location(), FIELD_DECL, name_tree, type_tree); DECL_CONTEXT(field) = fill_tree; *pp = field; pp = &DECL_CHAIN(field); } TYPE_FIELDS(fill_tree) = field_trees; layout_type(fill_tree); return fill; } // Make an array type. Btype* Gcc_backend::array_type(Btype* element_btype, Bexpression* length) { return this->fill_in_array(this->make_type(make_node(ARRAY_TYPE)), element_btype, length); } // Fill in an array type. Btype* Gcc_backend::fill_in_array(Btype* fill, Btype* element_type, Bexpression* length) { tree element_type_tree = element_type->get_tree(); tree length_tree = length->get_tree(); if (element_type_tree == error_mark_node || length_tree == error_mark_node) return this->error_type(); gcc_assert(TYPE_SIZE(element_type_tree) != NULL_TREE); length_tree = fold_convert(sizetype, length_tree); // build_index_type takes the maximum index, which is one less than // the length. tree index_type_tree = build_index_type(fold_build2(MINUS_EXPR, sizetype, length_tree, size_one_node)); tree fill_tree = fill->get_tree(); TREE_TYPE(fill_tree) = element_type_tree; TYPE_DOMAIN(fill_tree) = index_type_tree; TYPE_ADDR_SPACE(fill_tree) = TYPE_ADDR_SPACE(element_type_tree); layout_type(fill_tree); if (TYPE_STRUCTURAL_EQUALITY_P(element_type_tree)) SET_TYPE_STRUCTURAL_EQUALITY(fill_tree); else if (TYPE_CANONICAL(element_type_tree) != element_type_tree || TYPE_CANONICAL(index_type_tree) != index_type_tree) TYPE_CANONICAL(fill_tree) = build_array_type(TYPE_CANONICAL(element_type_tree), TYPE_CANONICAL(index_type_tree)); return fill; } // Create a placeholder for a pointer type. Btype* Gcc_backend::placeholder_pointer_type(const std::string& name, Location location, bool) { tree ret = build_distinct_type_copy(ptr_type_node); if (!name.empty()) { tree decl = build_decl(location.gcc_location(), TYPE_DECL, get_identifier_from_string(name), ret); TYPE_NAME(ret) = decl; } return this->make_type(ret); } // Set the real target type for a placeholder pointer type. bool Gcc_backend::set_placeholder_pointer_type(Btype* placeholder, Btype* to_type) { tree pt = placeholder->get_tree(); if (pt == error_mark_node) return false; gcc_assert(TREE_CODE(pt) == POINTER_TYPE); tree tt = to_type->get_tree(); if (tt == error_mark_node) { placeholder->set_tree(error_mark_node); return false; } gcc_assert(TREE_CODE(tt) == POINTER_TYPE); TREE_TYPE(pt) = TREE_TYPE(tt); if (TYPE_NAME(pt) != NULL_TREE) { // Build the data structure gcc wants to see for a typedef. tree copy = build_variant_type_copy(pt); TYPE_NAME(copy) = NULL_TREE; DECL_ORIGINAL_TYPE(TYPE_NAME(pt)) = copy; } return true; } // Set the real values for a placeholder function type. bool Gcc_backend::set_placeholder_function_type(Btype* placeholder, Btype* ft) { return this->set_placeholder_pointer_type(placeholder, ft); } // Create a placeholder for a struct type. Btype* Gcc_backend::placeholder_struct_type(const std::string& name, Location location) { tree ret = make_node(RECORD_TYPE); if (!name.empty()) { tree decl = build_decl(location.gcc_location(), TYPE_DECL, get_identifier_from_string(name), ret); TYPE_NAME(ret) = decl; } return this->make_type(ret); } // Fill in the fields of a placeholder struct type. bool Gcc_backend::set_placeholder_struct_type( Btype* placeholder, const std::vector& fields) { tree t = placeholder->get_tree(); gcc_assert(TREE_CODE(t) == RECORD_TYPE && TYPE_FIELDS(t) == NULL_TREE); Btype* r = this->fill_in_struct(placeholder, fields); if (TYPE_NAME(t) != NULL_TREE) { // Build the data structure gcc wants to see for a typedef. tree copy = build_distinct_type_copy(t); TYPE_NAME(copy) = NULL_TREE; DECL_ORIGINAL_TYPE(TYPE_NAME(t)) = copy; } return r->get_tree() != error_mark_node; } // Create a placeholder for an array type. Btype* Gcc_backend::placeholder_array_type(const std::string& name, Location location) { tree ret = make_node(ARRAY_TYPE); tree decl = build_decl(location.gcc_location(), TYPE_DECL, get_identifier_from_string(name), ret); TYPE_NAME(ret) = decl; return this->make_type(ret); } // Fill in the fields of a placeholder array type. bool Gcc_backend::set_placeholder_array_type(Btype* placeholder, Btype* element_btype, Bexpression* length) { tree t = placeholder->get_tree(); gcc_assert(TREE_CODE(t) == ARRAY_TYPE && TREE_TYPE(t) == NULL_TREE); Btype* r = this->fill_in_array(placeholder, element_btype, length); // Build the data structure gcc wants to see for a typedef. tree copy = build_distinct_type_copy(t); TYPE_NAME(copy) = NULL_TREE; DECL_ORIGINAL_TYPE(TYPE_NAME(t)) = copy; return r->get_tree() != error_mark_node; } // Return a named version of a type. Btype* Gcc_backend::named_type(const std::string& name, Btype* btype, Location location) { tree type = btype->get_tree(); if (type == error_mark_node) return this->error_type(); // The middle-end expects a basic type to have a name. In Go every // basic type will have a name. The first time we see a basic type, // give it whatever Go name we have at this point. if (TYPE_NAME(type) == NULL_TREE && location.gcc_location() == BUILTINS_LOCATION && (TREE_CODE(type) == INTEGER_TYPE || TREE_CODE(type) == REAL_TYPE || TREE_CODE(type) == COMPLEX_TYPE || TREE_CODE(type) == BOOLEAN_TYPE)) { tree decl = build_decl(BUILTINS_LOCATION, TYPE_DECL, get_identifier_from_string(name), type); TYPE_NAME(type) = decl; return this->make_type(type); } tree copy = build_variant_type_copy(type); tree decl = build_decl(location.gcc_location(), TYPE_DECL, get_identifier_from_string(name), copy); DECL_ORIGINAL_TYPE(decl) = type; TYPE_NAME(copy) = decl; return this->make_type(copy); } // Return a pointer type used as a marker for a circular type. Btype* Gcc_backend::circular_pointer_type(Btype*, bool) { return this->make_type(ptr_type_node); } // Return whether we might be looking at a circular type. bool Gcc_backend::is_circular_pointer_type(Btype* btype) { return btype->get_tree() == ptr_type_node; } // Return the size of a type. int64_t Gcc_backend::type_size(Btype* btype) { tree t = btype->get_tree(); if (t == error_mark_node) return 1; t = TYPE_SIZE_UNIT(t); gcc_assert(tree_fits_uhwi_p (t)); unsigned HOST_WIDE_INT val_wide = TREE_INT_CST_LOW(t); int64_t ret = static_cast(val_wide); if (ret < 0 || static_cast(ret) != val_wide) return -1; return ret; } // Return the alignment of a type. int64_t Gcc_backend::type_alignment(Btype* btype) { tree t = btype->get_tree(); if (t == error_mark_node) return 1; return TYPE_ALIGN_UNIT(t); } // Return the alignment of a struct field of type BTYPE. int64_t Gcc_backend::type_field_alignment(Btype* btype) { tree t = btype->get_tree(); if (t == error_mark_node) return 1; return go_field_alignment(t); } // Return the offset of a field in a struct. int64_t Gcc_backend::type_field_offset(Btype* btype, size_t index) { tree struct_tree = btype->get_tree(); if (struct_tree == error_mark_node) return 0; gcc_assert(TREE_CODE(struct_tree) == RECORD_TYPE); tree field = TYPE_FIELDS(struct_tree); for (; index > 0; --index) { field = DECL_CHAIN(field); gcc_assert(field != NULL_TREE); } HOST_WIDE_INT offset_wide = int_byte_position(field); int64_t ret = static_cast(offset_wide); gcc_assert(ret == offset_wide); return ret; } // Return the zero value for a type. Bexpression* Gcc_backend::zero_expression(Btype* btype) { tree t = btype->get_tree(); tree ret; if (t == error_mark_node) ret = error_mark_node; else ret = build_zero_cst(t); return this->make_expression(ret); } // An expression that references a variable. Bexpression* Gcc_backend::var_expression(Bvariable* var, Varexpr_context, Location location) { tree ret = var->get_tree(location); if (ret == error_mark_node) return this->error_expression(); return this->make_expression(ret); } // An expression that indirectly references an expression. Bexpression* Gcc_backend::indirect_expression(Btype* btype, Bexpression* expr, bool known_valid, Location location) { tree expr_tree = expr->get_tree(); tree type_tree = btype->get_tree(); if (expr_tree == error_mark_node || type_tree == error_mark_node) return this->error_expression(); // If the type of EXPR is a recursive pointer type, then we // need to insert a cast before indirecting. tree target_type_tree = TREE_TYPE(TREE_TYPE(expr_tree)); if (VOID_TYPE_P(target_type_tree)) expr_tree = fold_convert_loc(location.gcc_location(), build_pointer_type(type_tree), expr_tree); tree ret = build_fold_indirect_ref_loc(location.gcc_location(), expr_tree); if (known_valid) TREE_THIS_NOTRAP(ret) = 1; return this->make_expression(ret); } // Return an expression that declares a constant named NAME with the // constant value VAL in BTYPE. Bexpression* Gcc_backend::named_constant_expression(Btype* btype, const std::string& name, Bexpression* val, Location location) { tree type_tree = btype->get_tree(); tree const_val = val->get_tree(); if (type_tree == error_mark_node || const_val == error_mark_node) return this->error_expression(); tree name_tree = get_identifier_from_string(name); tree decl = build_decl(location.gcc_location(), CONST_DECL, name_tree, type_tree); DECL_INITIAL(decl) = const_val; TREE_CONSTANT(decl) = 1; TREE_READONLY(decl) = 1; go_preserve_from_gc(decl); return this->make_expression(decl); } // Return a typed value as a constant integer. Bexpression* Gcc_backend::integer_constant_expression(Btype* btype, mpz_t val) { tree t = btype->get_tree(); if (t == error_mark_node) return this->error_expression(); tree ret = double_int_to_tree(t, mpz_get_double_int(t, val, true)); return this->make_expression(ret); } // Return a typed value as a constant floating-point number. Bexpression* Gcc_backend::float_constant_expression(Btype* btype, mpfr_t val) { tree t = btype->get_tree(); tree ret; if (t == error_mark_node) return this->error_expression(); REAL_VALUE_TYPE r1; real_from_mpfr(&r1, val, t, GMP_RNDN); REAL_VALUE_TYPE r2; real_convert(&r2, TYPE_MODE(t), &r1); ret = build_real(t, r2); return this->make_expression(ret); } // Return a typed real and imaginary value as a constant complex number. Bexpression* Gcc_backend::complex_constant_expression(Btype* btype, mpc_t val) { tree t = btype->get_tree(); tree ret; if (t == error_mark_node) return this->error_expression(); REAL_VALUE_TYPE r1; real_from_mpfr(&r1, mpc_realref(val), TREE_TYPE(t), GMP_RNDN); REAL_VALUE_TYPE r2; real_convert(&r2, TYPE_MODE(TREE_TYPE(t)), &r1); REAL_VALUE_TYPE r3; real_from_mpfr(&r3, mpc_imagref(val), TREE_TYPE(t), GMP_RNDN); REAL_VALUE_TYPE r4; real_convert(&r4, TYPE_MODE(TREE_TYPE(t)), &r3); ret = build_complex(t, build_real(TREE_TYPE(t), r2), build_real(TREE_TYPE(t), r4)); return this->make_expression(ret); } // Make a constant string expression. Bexpression* Gcc_backend::string_constant_expression(const std::string& val) { tree index_type = build_index_type(size_int(val.length())); tree const_char_type = build_qualified_type(unsigned_char_type_node, TYPE_QUAL_CONST); tree string_type = build_array_type(const_char_type, index_type); TYPE_STRING_FLAG(string_type) = 1; tree string_val = build_string(val.length(), val.data()); TREE_TYPE(string_val) = string_type; return this->make_expression(string_val); } // Make a constant boolean expression. Bexpression* Gcc_backend::boolean_constant_expression(bool val) { tree bool_cst = val ? boolean_true_node : boolean_false_node; return this->make_expression(bool_cst); } // Return the real part of a complex expression. Bexpression* Gcc_backend::real_part_expression(Bexpression* bcomplex, Location location) { tree complex_tree = bcomplex->get_tree(); if (complex_tree == error_mark_node) return this->error_expression(); gcc_assert(COMPLEX_FLOAT_TYPE_P(TREE_TYPE(complex_tree))); tree ret = fold_build1_loc(location.gcc_location(), REALPART_EXPR, TREE_TYPE(TREE_TYPE(complex_tree)), complex_tree); return this->make_expression(ret); } // Return the imaginary part of a complex expression. Bexpression* Gcc_backend::imag_part_expression(Bexpression* bcomplex, Location location) { tree complex_tree = bcomplex->get_tree(); if (complex_tree == error_mark_node) return this->error_expression(); gcc_assert(COMPLEX_FLOAT_TYPE_P(TREE_TYPE(complex_tree))); tree ret = fold_build1_loc(location.gcc_location(), IMAGPART_EXPR, TREE_TYPE(TREE_TYPE(complex_tree)), complex_tree); return this->make_expression(ret); } // Make a complex expression given its real and imaginary parts. Bexpression* Gcc_backend::complex_expression(Bexpression* breal, Bexpression* bimag, Location location) { tree real_tree = breal->get_tree(); tree imag_tree = bimag->get_tree(); if (real_tree == error_mark_node || imag_tree == error_mark_node) return this->error_expression(); gcc_assert(TYPE_MAIN_VARIANT(TREE_TYPE(real_tree)) == TYPE_MAIN_VARIANT(TREE_TYPE(imag_tree))); gcc_assert(SCALAR_FLOAT_TYPE_P(TREE_TYPE(real_tree))); tree ret = fold_build2_loc(location.gcc_location(), COMPLEX_EXPR, build_complex_type(TREE_TYPE(real_tree)), real_tree, imag_tree); return this->make_expression(ret); } // An expression that converts an expression to a different type. Bexpression* Gcc_backend::convert_expression(Btype* type, Bexpression* expr, Location location) { tree type_tree = type->get_tree(); tree expr_tree = expr->get_tree(); if (type_tree == error_mark_node || expr_tree == error_mark_node || TREE_TYPE(expr_tree) == error_mark_node) return this->error_expression(); tree ret; if (this->type_size(type) == 0) { // Do not convert zero-sized types. ret = expr_tree; } else if (TREE_CODE(type_tree) == INTEGER_TYPE) ret = fold(convert_to_integer(type_tree, expr_tree)); else if (TREE_CODE(type_tree) == REAL_TYPE) ret = fold(convert_to_real(type_tree, expr_tree)); else if (TREE_CODE(type_tree) == COMPLEX_TYPE) ret = fold(convert_to_complex(type_tree, expr_tree)); else if (TREE_CODE(type_tree) == POINTER_TYPE && TREE_CODE(TREE_TYPE(expr_tree)) == INTEGER_TYPE) ret = fold(convert_to_pointer(type_tree, expr_tree)); else if (TREE_CODE(type_tree) == RECORD_TYPE || TREE_CODE(type_tree) == ARRAY_TYPE) ret = fold_build1_loc(location.gcc_location(), VIEW_CONVERT_EXPR, type_tree, expr_tree); else ret = fold_convert_loc(location.gcc_location(), type_tree, expr_tree); return this->make_expression(ret); } // Get the address of a function. Bexpression* Gcc_backend::function_code_expression(Bfunction* bfunc, Location location) { tree func = bfunc->get_tree(); if (func == error_mark_node) return this->error_expression(); tree ret = build_fold_addr_expr_loc(location.gcc_location(), func); return this->make_expression(ret); } // Get the address of an expression. Bexpression* Gcc_backend::address_expression(Bexpression* bexpr, Location location) { tree expr = bexpr->get_tree(); if (expr == error_mark_node) return this->error_expression(); tree ret = build_fold_addr_expr_loc(location.gcc_location(), expr); return this->make_expression(ret); } // Return an expression for the field at INDEX in BSTRUCT. Bexpression* Gcc_backend::struct_field_expression(Bexpression* bstruct, size_t index, Location location) { tree struct_tree = bstruct->get_tree(); if (struct_tree == error_mark_node || TREE_TYPE(struct_tree) == error_mark_node) return this->error_expression(); gcc_assert(TREE_CODE(TREE_TYPE(struct_tree)) == RECORD_TYPE); tree field = TYPE_FIELDS(TREE_TYPE(struct_tree)); if (field == NULL_TREE) { // This can happen for a type which refers to itself indirectly // and then turns out to be erroneous. return this->error_expression(); } for (unsigned int i = index; i > 0; --i) { field = DECL_CHAIN(field); gcc_assert(field != NULL_TREE); } if (TREE_TYPE(field) == error_mark_node) return this->error_expression(); tree ret = fold_build3_loc(location.gcc_location(), COMPONENT_REF, TREE_TYPE(field), struct_tree, field, NULL_TREE); if (TREE_CONSTANT(struct_tree)) TREE_CONSTANT(ret) = 1; return this->make_expression(ret); } // Return an expression that executes BSTAT before BEXPR. Bexpression* Gcc_backend::compound_expression(Bstatement* bstat, Bexpression* bexpr, Location location) { tree stat = bstat->get_tree(); tree expr = bexpr->get_tree(); if (stat == error_mark_node || expr == error_mark_node) return this->error_expression(); tree ret = fold_build2_loc(location.gcc_location(), COMPOUND_EXPR, TREE_TYPE(expr), stat, expr); return this->make_expression(ret); } // Return an expression that executes THEN_EXPR if CONDITION is true, or // ELSE_EXPR otherwise. Bexpression* Gcc_backend::conditional_expression(Bfunction*, Btype* btype, Bexpression* condition, Bexpression* then_expr, Bexpression* else_expr, Location location) { tree type_tree = btype == NULL ? void_type_node : btype->get_tree(); tree cond_tree = condition->get_tree(); tree then_tree = then_expr->get_tree(); tree else_tree = else_expr == NULL ? NULL_TREE : else_expr->get_tree(); if (type_tree == error_mark_node || cond_tree == error_mark_node || then_tree == error_mark_node || else_tree == error_mark_node) return this->error_expression(); tree ret = build3_loc(location.gcc_location(), COND_EXPR, type_tree, cond_tree, then_tree, else_tree); return this->make_expression(ret); } // Return an expression for the unary operation OP EXPR. Bexpression* Gcc_backend::unary_expression(Operator op, Bexpression* expr, Location location) { tree expr_tree = expr->get_tree(); if (expr_tree == error_mark_node || TREE_TYPE(expr_tree) == error_mark_node) return this->error_expression(); tree type_tree = TREE_TYPE(expr_tree); enum tree_code code; switch (op) { case OPERATOR_MINUS: { tree computed_type = excess_precision_type(type_tree); if (computed_type != NULL_TREE) { expr_tree = convert(computed_type, expr_tree); type_tree = computed_type; } code = NEGATE_EXPR; break; } case OPERATOR_NOT: code = TRUTH_NOT_EXPR; break; case OPERATOR_XOR: code = BIT_NOT_EXPR; break; default: gcc_unreachable(); break; } tree ret = fold_build1_loc(location.gcc_location(), code, type_tree, expr_tree); return this->make_expression(ret); } // Convert a gofrontend operator to an equivalent tree_code. static enum tree_code operator_to_tree_code(Operator op, tree type) { enum tree_code code; switch (op) { case OPERATOR_EQEQ: code = EQ_EXPR; break; case OPERATOR_NOTEQ: code = NE_EXPR; break; case OPERATOR_LT: code = LT_EXPR; break; case OPERATOR_LE: code = LE_EXPR; break; case OPERATOR_GT: code = GT_EXPR; break; case OPERATOR_GE: code = GE_EXPR; break; case OPERATOR_OROR: code = TRUTH_ORIF_EXPR; break; case OPERATOR_ANDAND: code = TRUTH_ANDIF_EXPR; break; case OPERATOR_PLUS: code = PLUS_EXPR; break; case OPERATOR_MINUS: code = MINUS_EXPR; break; case OPERATOR_OR: code = BIT_IOR_EXPR; break; case OPERATOR_XOR: code = BIT_XOR_EXPR; break; case OPERATOR_MULT: code = MULT_EXPR; break; case OPERATOR_DIV: if (TREE_CODE(type) == REAL_TYPE || TREE_CODE(type) == COMPLEX_TYPE) code = RDIV_EXPR; else code = TRUNC_DIV_EXPR; break; case OPERATOR_MOD: code = TRUNC_MOD_EXPR; break; case OPERATOR_LSHIFT: code = LSHIFT_EXPR; break; case OPERATOR_RSHIFT: code = RSHIFT_EXPR; break; case OPERATOR_AND: code = BIT_AND_EXPR; break; case OPERATOR_BITCLEAR: code = BIT_AND_EXPR; break; default: gcc_unreachable(); } return code; } // Return an expression for the binary operation LEFT OP RIGHT. Bexpression* Gcc_backend::binary_expression(Operator op, Bexpression* left, Bexpression* right, Location location) { tree left_tree = left->get_tree(); tree right_tree = right->get_tree(); if (left_tree == error_mark_node || right_tree == error_mark_node) return this->error_expression(); enum tree_code code = operator_to_tree_code(op, TREE_TYPE(left_tree)); bool use_left_type = op != OPERATOR_OROR && op != OPERATOR_ANDAND; tree type_tree = use_left_type ? TREE_TYPE(left_tree) : TREE_TYPE(right_tree); tree computed_type = excess_precision_type(type_tree); if (computed_type != NULL_TREE) { left_tree = convert(computed_type, left_tree); right_tree = convert(computed_type, right_tree); type_tree = computed_type; } // For comparison operators, the resulting type should be boolean. switch (op) { case OPERATOR_EQEQ: case OPERATOR_NOTEQ: case OPERATOR_LT: case OPERATOR_LE: case OPERATOR_GT: case OPERATOR_GE: type_tree = boolean_type_node; break; default: break; } tree ret = fold_build2_loc(location.gcc_location(), code, type_tree, left_tree, right_tree); return this->make_expression(ret); } // Return an expression that constructs BTYPE with VALS. Bexpression* Gcc_backend::constructor_expression(Btype* btype, const std::vector& vals, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_expression(); vec *init; vec_alloc(init, vals.size()); tree sink = NULL_TREE; bool is_constant = true; tree field = TYPE_FIELDS(type_tree); for (std::vector::const_iterator p = vals.begin(); p != vals.end(); ++p, field = DECL_CHAIN(field)) { gcc_assert(field != NULL_TREE); tree val = (*p)->get_tree(); if (TREE_TYPE(field) == error_mark_node || val == error_mark_node || TREE_TYPE(val) == error_mark_node) return this->error_expression(); if (int_size_in_bytes(TREE_TYPE(field)) == 0) { // GIMPLE cannot represent indices of zero-sized types so // trying to construct a map with zero-sized keys might lead // to errors. Instead, we evaluate each expression that // would have been added as a map element for its // side-effects and construct an empty map. append_to_statement_list(val, &sink); continue; } constructor_elt empty = {NULL, NULL}; constructor_elt* elt = init->quick_push(empty); elt->index = field; elt->value = fold_convert_loc(location.gcc_location(), TREE_TYPE(field), val); if (!TREE_CONSTANT(elt->value)) is_constant = false; } gcc_assert(field == NULL_TREE); tree ret = build_constructor(type_tree, init); if (is_constant) TREE_CONSTANT(ret) = 1; if (sink != NULL_TREE) ret = fold_build2_loc(location.gcc_location(), COMPOUND_EXPR, type_tree, sink, ret); return this->make_expression(ret); } Bexpression* Gcc_backend::array_constructor_expression( Btype* array_btype, const std::vector& indexes, const std::vector& vals, Location location) { tree type_tree = array_btype->get_tree(); if (type_tree == error_mark_node) return this->error_expression(); gcc_assert(indexes.size() == vals.size()); tree element_type = TREE_TYPE(type_tree); HOST_WIDE_INT element_size = int_size_in_bytes(element_type); vec *init; vec_alloc(init, element_size == 0 ? 0 : vals.size()); tree sink = NULL_TREE; bool is_constant = true; for (size_t i = 0; i < vals.size(); ++i) { tree index = size_int(indexes[i]); tree val = (vals[i])->get_tree(); if (index == error_mark_node || val == error_mark_node) return this->error_expression(); if (element_size == 0) { // GIMPLE cannot represent arrays of zero-sized types so trying // to construct an array of zero-sized values might lead to errors. // Instead, we evaluate each expression that would have been added as // an array value for its side-effects and construct an empty array. append_to_statement_list(val, &sink); continue; } if (!TREE_CONSTANT(val)) is_constant = false; constructor_elt empty = {NULL, NULL}; constructor_elt* elt = init->quick_push(empty); elt->index = index; elt->value = val; } tree ret = build_constructor(type_tree, init); if (is_constant) TREE_CONSTANT(ret) = 1; if (sink != NULL_TREE) ret = fold_build2_loc(location.gcc_location(), COMPOUND_EXPR, type_tree, sink, ret); return this->make_expression(ret); } // Return an expression for the address of BASE[INDEX]. Bexpression* Gcc_backend::pointer_offset_expression(Bexpression* base, Bexpression* index, Location location) { tree base_tree = base->get_tree(); tree index_tree = index->get_tree(); tree element_type_tree = TREE_TYPE(TREE_TYPE(base_tree)); if (base_tree == error_mark_node || TREE_TYPE(base_tree) == error_mark_node || index_tree == error_mark_node || element_type_tree == error_mark_node) return this->error_expression(); tree element_size = TYPE_SIZE_UNIT(element_type_tree); index_tree = fold_convert_loc(location.gcc_location(), sizetype, index_tree); tree offset = fold_build2_loc(location.gcc_location(), MULT_EXPR, sizetype, index_tree, element_size); tree ptr = fold_build2_loc(location.gcc_location(), POINTER_PLUS_EXPR, TREE_TYPE(base_tree), base_tree, offset); return this->make_expression(ptr); } // Return an expression representing ARRAY[INDEX] Bexpression* Gcc_backend::array_index_expression(Bexpression* array, Bexpression* index, Location location) { tree array_tree = array->get_tree(); tree index_tree = index->get_tree(); if (array_tree == error_mark_node || TREE_TYPE(array_tree) == error_mark_node || index_tree == error_mark_node) return this->error_expression(); tree ret = build4_loc(location.gcc_location(), ARRAY_REF, TREE_TYPE(TREE_TYPE(array_tree)), array_tree, index_tree, NULL_TREE, NULL_TREE); return this->make_expression(ret); } // Create an expression for a call to FN_EXPR with FN_ARGS. Bexpression* Gcc_backend::call_expression(Bexpression* fn_expr, const std::vector& fn_args, Bexpression* chain_expr, Location location) { tree fn = fn_expr->get_tree(); if (fn == error_mark_node || TREE_TYPE(fn) == error_mark_node) return this->error_expression(); gcc_assert(FUNCTION_POINTER_TYPE_P(TREE_TYPE(fn))); tree rettype = TREE_TYPE(TREE_TYPE(TREE_TYPE(fn))); size_t nargs = fn_args.size(); tree* args = nargs == 0 ? NULL : new tree[nargs]; for (size_t i = 0; i < nargs; ++i) { args[i] = fn_args.at(i)->get_tree(); if (args[i] == error_mark_node) return this->error_expression(); } tree fndecl = fn; if (TREE_CODE(fndecl) == ADDR_EXPR) fndecl = TREE_OPERAND(fndecl, 0); // This is to support builtin math functions when using 80387 math. tree excess_type = NULL_TREE; if (optimize && TREE_CODE(fndecl) == FUNCTION_DECL && DECL_IS_BUILTIN(fndecl) && DECL_BUILT_IN_CLASS(fndecl) == BUILT_IN_NORMAL && nargs > 0 && ((SCALAR_FLOAT_TYPE_P(rettype) && SCALAR_FLOAT_TYPE_P(TREE_TYPE(args[0]))) || (COMPLEX_FLOAT_TYPE_P(rettype) && COMPLEX_FLOAT_TYPE_P(TREE_TYPE(args[0]))))) { excess_type = excess_precision_type(TREE_TYPE(args[0])); if (excess_type != NULL_TREE) { tree excess_fndecl = mathfn_built_in(excess_type, DECL_FUNCTION_CODE(fndecl)); if (excess_fndecl == NULL_TREE) excess_type = NULL_TREE; else { fn = build_fold_addr_expr_loc(location.gcc_location(), excess_fndecl); for (size_t i = 0; i < nargs; ++i) { if (SCALAR_FLOAT_TYPE_P(TREE_TYPE(args[i])) || COMPLEX_FLOAT_TYPE_P(TREE_TYPE(args[i]))) args[i] = ::convert(excess_type, args[i]); } } } } tree ret = build_call_array_loc(location.gcc_location(), excess_type != NULL_TREE ? excess_type : rettype, fn, nargs, args); if (chain_expr) CALL_EXPR_STATIC_CHAIN (ret) = chain_expr->get_tree(); if (excess_type != NULL_TREE) { // Calling convert here can undo our excess precision change. // That may or may not be a bug in convert_to_real. ret = build1_loc(location.gcc_location(), NOP_EXPR, rettype, ret); } delete[] args; return this->make_expression(ret); } // Return an expression that allocates SIZE bytes on the stack. Bexpression* Gcc_backend::stack_allocation_expression(int64_t size, Location location) { tree alloca = builtin_decl_explicit(BUILT_IN_ALLOCA); tree size_tree = build_int_cst(integer_type_node, size); tree ret = build_call_expr_loc(location.gcc_location(), alloca, 1, size_tree); tree memset = builtin_decl_explicit(BUILT_IN_MEMSET); ret = build_call_expr_loc(location.gcc_location(), memset, 3, ret, integer_zero_node, size_tree); return this->make_expression(ret); } // An expression as a statement. Bstatement* Gcc_backend::expression_statement(Bfunction*, Bexpression* expr) { return this->make_statement(expr->get_tree()); } // Variable initialization. Bstatement* Gcc_backend::init_statement(Bfunction*, Bvariable* var, Bexpression* init) { tree var_tree = var->get_decl(); tree init_tree = init->get_tree(); if (var_tree == error_mark_node || init_tree == error_mark_node) return this->error_statement(); gcc_assert(TREE_CODE(var_tree) == VAR_DECL); // To avoid problems with GNU ld, we don't make zero-sized // externally visible variables. That might lead us to doing an // initialization of a zero-sized expression to a non-zero sized // variable, or vice-versa. Avoid crashes by omitting the // initializer. Such initializations don't mean anything anyhow. if (int_size_in_bytes(TREE_TYPE(var_tree)) != 0 && init_tree != NULL_TREE && int_size_in_bytes(TREE_TYPE(init_tree)) != 0) { DECL_INITIAL(var_tree) = init_tree; init_tree = NULL_TREE; } tree ret = build1_loc(DECL_SOURCE_LOCATION(var_tree), DECL_EXPR, void_type_node, var_tree); if (init_tree != NULL_TREE) ret = build2_loc(DECL_SOURCE_LOCATION(var_tree), COMPOUND_EXPR, void_type_node, init_tree, ret); return this->make_statement(ret); } // Assignment. Bstatement* Gcc_backend::assignment_statement(Bfunction* bfn, Bexpression* lhs, Bexpression* rhs, Location location) { tree lhs_tree = lhs->get_tree(); tree rhs_tree = rhs->get_tree(); if (lhs_tree == error_mark_node || rhs_tree == error_mark_node) return this->error_statement(); // To avoid problems with GNU ld, we don't make zero-sized // externally visible variables. That might lead us to doing an // assignment of a zero-sized expression to a non-zero sized // expression; avoid crashes here by avoiding assignments of // zero-sized expressions. Such assignments don't really mean // anything anyhow. if (int_size_in_bytes(TREE_TYPE(lhs_tree)) == 0 || int_size_in_bytes(TREE_TYPE(rhs_tree)) == 0) return this->compound_statement(this->expression_statement(bfn, lhs), this->expression_statement(bfn, rhs)); // Sometimes the same unnamed Go type can be created multiple times // and thus have multiple tree representations. Make sure this does // not confuse the middle-end. if (TREE_TYPE(lhs_tree) != TREE_TYPE(rhs_tree)) { tree lhs_type_tree = TREE_TYPE(lhs_tree); gcc_assert(TREE_CODE(lhs_type_tree) == TREE_CODE(TREE_TYPE(rhs_tree))); if (POINTER_TYPE_P(lhs_type_tree) || INTEGRAL_TYPE_P(lhs_type_tree) || SCALAR_FLOAT_TYPE_P(lhs_type_tree) || COMPLEX_FLOAT_TYPE_P(lhs_type_tree)) rhs_tree = fold_convert_loc(location.gcc_location(), lhs_type_tree, rhs_tree); else if (TREE_CODE(lhs_type_tree) == RECORD_TYPE || TREE_CODE(lhs_type_tree) == ARRAY_TYPE) { gcc_assert(int_size_in_bytes(lhs_type_tree) == int_size_in_bytes(TREE_TYPE(rhs_tree))); rhs_tree = fold_build1_loc(location.gcc_location(), VIEW_CONVERT_EXPR, lhs_type_tree, rhs_tree); } } return this->make_statement(fold_build2_loc(location.gcc_location(), MODIFY_EXPR, void_type_node, lhs_tree, rhs_tree)); } // Return. Bstatement* Gcc_backend::return_statement(Bfunction* bfunction, const std::vector& vals, Location location) { tree fntree = bfunction->get_tree(); if (fntree == error_mark_node) return this->error_statement(); tree result = DECL_RESULT(fntree); if (result == error_mark_node) return this->error_statement(); // If the result size is zero bytes, we have set the function type // to have a result type of void, so don't return anything. // See the function_type method. tree res_type = TREE_TYPE(result); if (res_type == void_type_node || int_size_in_bytes(res_type) == 0) { tree stmt_list = NULL_TREE; for (std::vector::const_iterator p = vals.begin(); p != vals.end(); p++) { tree val = (*p)->get_tree(); if (val == error_mark_node) return this->error_statement(); append_to_statement_list(val, &stmt_list); } tree ret = fold_build1_loc(location.gcc_location(), RETURN_EXPR, void_type_node, NULL_TREE); append_to_statement_list(ret, &stmt_list); return this->make_statement(stmt_list); } tree ret; if (vals.empty()) ret = fold_build1_loc(location.gcc_location(), RETURN_EXPR, void_type_node, NULL_TREE); else if (vals.size() == 1) { tree val = vals.front()->get_tree(); if (val == error_mark_node) return this->error_statement(); tree set = fold_build2_loc(location.gcc_location(), MODIFY_EXPR, void_type_node, result, vals.front()->get_tree()); ret = fold_build1_loc(location.gcc_location(), RETURN_EXPR, void_type_node, set); } else { // To return multiple values, copy the values into a temporary // variable of the right structure type, and then assign the // temporary variable to the DECL_RESULT in the return // statement. tree stmt_list = NULL_TREE; tree rettype = TREE_TYPE(result); if (DECL_STRUCT_FUNCTION(fntree) == NULL) push_struct_function(fntree); else push_cfun(DECL_STRUCT_FUNCTION(fntree)); tree rettmp = create_tmp_var(rettype, "RESULT"); pop_cfun(); tree field = TYPE_FIELDS(rettype); for (std::vector::const_iterator p = vals.begin(); p != vals.end(); p++, field = DECL_CHAIN(field)) { gcc_assert(field != NULL_TREE); tree ref = fold_build3_loc(location.gcc_location(), COMPONENT_REF, TREE_TYPE(field), rettmp, field, NULL_TREE); tree val = (*p)->get_tree(); if (val == error_mark_node) return this->error_statement(); tree set = fold_build2_loc(location.gcc_location(), MODIFY_EXPR, void_type_node, ref, (*p)->get_tree()); append_to_statement_list(set, &stmt_list); } gcc_assert(field == NULL_TREE); tree set = fold_build2_loc(location.gcc_location(), MODIFY_EXPR, void_type_node, result, rettmp); tree ret_expr = fold_build1_loc(location.gcc_location(), RETURN_EXPR, void_type_node, set); append_to_statement_list(ret_expr, &stmt_list); ret = stmt_list; } return this->make_statement(ret); } // Create a statement that attempts to execute BSTAT and calls EXCEPT_STMT if an // error occurs. EXCEPT_STMT may be NULL. FINALLY_STMT may be NULL and if not // NULL, it will always be executed. This is used for handling defers in Go // functions. In C++, the resulting code is of this form: // try { BSTAT; } catch { EXCEPT_STMT; } finally { FINALLY_STMT; } Bstatement* Gcc_backend::exception_handler_statement(Bstatement* bstat, Bstatement* except_stmt, Bstatement* finally_stmt, Location location) { tree stat_tree = bstat->get_tree(); tree except_tree = except_stmt == NULL ? NULL_TREE : except_stmt->get_tree(); tree finally_tree = finally_stmt == NULL ? NULL_TREE : finally_stmt->get_tree(); if (stat_tree == error_mark_node || except_tree == error_mark_node || finally_tree == error_mark_node) return this->error_statement(); if (except_tree != NULL_TREE) stat_tree = build2_loc(location.gcc_location(), TRY_CATCH_EXPR, void_type_node, stat_tree, build2_loc(location.gcc_location(), CATCH_EXPR, void_type_node, NULL, except_tree)); if (finally_tree != NULL_TREE) stat_tree = build2_loc(location.gcc_location(), TRY_FINALLY_EXPR, void_type_node, stat_tree, finally_tree); return this->make_statement(stat_tree); } // If. Bstatement* Gcc_backend::if_statement(Bfunction*, Bexpression* condition, Bblock* then_block, Bblock* else_block, Location location) { tree cond_tree = condition->get_tree(); tree then_tree = then_block->get_tree(); tree else_tree = else_block == NULL ? NULL_TREE : else_block->get_tree(); if (cond_tree == error_mark_node || then_tree == error_mark_node || else_tree == error_mark_node) return this->error_statement(); tree ret = build3_loc(location.gcc_location(), COND_EXPR, void_type_node, cond_tree, then_tree, else_tree); return this->make_statement(ret); } // Switch. Bstatement* Gcc_backend::switch_statement( Bfunction* function, Bexpression* value, const std::vector >& cases, const std::vector& statements, Location switch_location) { gcc_assert(cases.size() == statements.size()); tree decl = function->get_tree(); if (DECL_STRUCT_FUNCTION(decl) == NULL) push_struct_function(decl); else push_cfun(DECL_STRUCT_FUNCTION(decl)); tree stmt_list = NULL_TREE; std::vector >::const_iterator pc = cases.begin(); for (std::vector::const_iterator ps = statements.begin(); ps != statements.end(); ++ps, ++pc) { if (pc->empty()) { source_location loc = (*ps != NULL ? EXPR_LOCATION((*ps)->get_tree()) : UNKNOWN_LOCATION); tree label = create_artificial_label(loc); tree c = build_case_label(NULL_TREE, NULL_TREE, label); append_to_statement_list(c, &stmt_list); } else { for (std::vector::const_iterator pcv = pc->begin(); pcv != pc->end(); ++pcv) { tree t = (*pcv)->get_tree(); if (t == error_mark_node) return this->error_statement(); source_location loc = EXPR_LOCATION(t); tree label = create_artificial_label(loc); tree c = build_case_label((*pcv)->get_tree(), NULL_TREE, label); append_to_statement_list(c, &stmt_list); } } if (*ps != NULL) { tree t = (*ps)->get_tree(); if (t == error_mark_node) return this->error_statement(); append_to_statement_list(t, &stmt_list); } } pop_cfun(); tree tv = value->get_tree(); if (tv == error_mark_node) return this->error_statement(); tree t = build3_loc(switch_location.gcc_location(), SWITCH_EXPR, NULL_TREE, tv, stmt_list, NULL_TREE); return this->make_statement(t); } // Pair of statements. Bstatement* Gcc_backend::compound_statement(Bstatement* s1, Bstatement* s2) { tree stmt_list = NULL_TREE; tree t = s1->get_tree(); if (t == error_mark_node) return this->error_statement(); append_to_statement_list(t, &stmt_list); t = s2->get_tree(); if (t == error_mark_node) return this->error_statement(); append_to_statement_list(t, &stmt_list); // If neither statement has any side effects, stmt_list can be NULL // at this point. if (stmt_list == NULL_TREE) stmt_list = integer_zero_node; return this->make_statement(stmt_list); } // List of statements. Bstatement* Gcc_backend::statement_list(const std::vector& statements) { tree stmt_list = NULL_TREE; for (std::vector::const_iterator p = statements.begin(); p != statements.end(); ++p) { tree t = (*p)->get_tree(); if (t == error_mark_node) return this->error_statement(); append_to_statement_list(t, &stmt_list); } return this->make_statement(stmt_list); } // Make a block. For some reason gcc uses a dual structure for // blocks: BLOCK tree nodes and BIND_EXPR tree nodes. Since the // BIND_EXPR node points to the BLOCK node, we store the BIND_EXPR in // the Bblock. Bblock* Gcc_backend::block(Bfunction* function, Bblock* enclosing, const std::vector& vars, Location start_location, Location) { tree block_tree = make_node(BLOCK); if (enclosing == NULL) { tree fndecl = function->get_tree(); gcc_assert(fndecl != NULL_TREE); // We may have already created a block for local variables when // we take the address of a parameter. if (DECL_INITIAL(fndecl) == NULL_TREE) { BLOCK_SUPERCONTEXT(block_tree) = fndecl; DECL_INITIAL(fndecl) = block_tree; } else { tree superblock_tree = DECL_INITIAL(fndecl); BLOCK_SUPERCONTEXT(block_tree) = superblock_tree; tree* pp; for (pp = &BLOCK_SUBBLOCKS(superblock_tree); *pp != NULL_TREE; pp = &BLOCK_CHAIN(*pp)) ; *pp = block_tree; } } else { tree superbind_tree = enclosing->get_tree(); tree superblock_tree = BIND_EXPR_BLOCK(superbind_tree); gcc_assert(TREE_CODE(superblock_tree) == BLOCK); BLOCK_SUPERCONTEXT(block_tree) = superblock_tree; tree* pp; for (pp = &BLOCK_SUBBLOCKS(superblock_tree); *pp != NULL_TREE; pp = &BLOCK_CHAIN(*pp)) ; *pp = block_tree; } tree* pp = &BLOCK_VARS(block_tree); for (std::vector::const_iterator pv = vars.begin(); pv != vars.end(); ++pv) { *pp = (*pv)->get_decl(); if (*pp != error_mark_node) pp = &DECL_CHAIN(*pp); } *pp = NULL_TREE; TREE_USED(block_tree) = 1; tree bind_tree = build3_loc(start_location.gcc_location(), BIND_EXPR, void_type_node, BLOCK_VARS(block_tree), NULL_TREE, block_tree); TREE_SIDE_EFFECTS(bind_tree) = 1; return new Bblock(bind_tree); } // Add statements to a block. void Gcc_backend::block_add_statements(Bblock* bblock, const std::vector& statements) { tree stmt_list = NULL_TREE; for (std::vector::const_iterator p = statements.begin(); p != statements.end(); ++p) { tree s = (*p)->get_tree(); if (s != error_mark_node) append_to_statement_list(s, &stmt_list); } tree bind_tree = bblock->get_tree(); gcc_assert(TREE_CODE(bind_tree) == BIND_EXPR); BIND_EXPR_BODY(bind_tree) = stmt_list; } // Return a block as a statement. Bstatement* Gcc_backend::block_statement(Bblock* bblock) { tree bind_tree = bblock->get_tree(); gcc_assert(TREE_CODE(bind_tree) == BIND_EXPR); return this->make_statement(bind_tree); } // This is not static because we declare it with GTY(()) in go-c.h. tree go_non_zero_struct; // Return a type corresponding to TYPE with non-zero size. tree Gcc_backend::non_zero_size_type(tree type) { if (int_size_in_bytes(type) != 0) return type; switch (TREE_CODE(type)) { case RECORD_TYPE: if (TYPE_FIELDS(type) != NULL_TREE) { tree ns = make_node(RECORD_TYPE); tree field_trees = NULL_TREE; tree *pp = &field_trees; for (tree field = TYPE_FIELDS(type); field != NULL_TREE; field = DECL_CHAIN(field)) { tree ft = TREE_TYPE(field); if (field == TYPE_FIELDS(type)) ft = non_zero_size_type(ft); tree f = build_decl(DECL_SOURCE_LOCATION(field), FIELD_DECL, DECL_NAME(field), ft); DECL_CONTEXT(f) = ns; *pp = f; pp = &DECL_CHAIN(f); } TYPE_FIELDS(ns) = field_trees; layout_type(ns); return ns; } if (go_non_zero_struct == NULL_TREE) { type = make_node(RECORD_TYPE); tree field = build_decl(UNKNOWN_LOCATION, FIELD_DECL, get_identifier("dummy"), boolean_type_node); DECL_CONTEXT(field) = type; TYPE_FIELDS(type) = field; layout_type(type); go_non_zero_struct = type; } return go_non_zero_struct; case ARRAY_TYPE: { tree element_type = non_zero_size_type(TREE_TYPE(type)); return build_array_type_nelts(element_type, 1); } default: gcc_unreachable(); } gcc_unreachable(); } // Make a global variable. Bvariable* Gcc_backend::global_variable(const std::string& var_name, const std::string& asm_name, Btype* btype, bool is_external, bool is_hidden, bool in_unique_section, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); // The GNU linker does not like dynamic variables with zero size. tree orig_type_tree = type_tree; if ((is_external || !is_hidden) && int_size_in_bytes(type_tree) == 0) type_tree = this->non_zero_size_type(type_tree); tree decl = build_decl(location.gcc_location(), VAR_DECL, get_identifier_from_string(var_name), type_tree); if (is_external) DECL_EXTERNAL(decl) = 1; else TREE_STATIC(decl) = 1; if (!is_hidden) { TREE_PUBLIC(decl) = 1; SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); } else { SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); } TREE_USED(decl) = 1; if (in_unique_section) resolve_unique_section (decl, 0, 1); go_preserve_from_gc(decl); return new Bvariable(decl, orig_type_tree); } // Set the initial value of a global variable. void Gcc_backend::global_variable_set_init(Bvariable* var, Bexpression* expr) { tree expr_tree = expr->get_tree(); if (expr_tree == error_mark_node) return; gcc_assert(TREE_CONSTANT(expr_tree)); tree var_decl = var->get_decl(); if (var_decl == error_mark_node) return; DECL_INITIAL(var_decl) = expr_tree; // If this variable goes in a unique section, it may need to go into // a different one now that DECL_INITIAL is set. if (symtab_node::get(var_decl) && symtab_node::get(var_decl)->implicit_section) { set_decl_section_name (var_decl, NULL); resolve_unique_section (var_decl, compute_reloc_for_constant (expr_tree), 1); } } // Make a local variable. Bvariable* Gcc_backend::local_variable(Bfunction* function, const std::string& name, Btype* btype, bool is_address_taken, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); tree decl = build_decl(location.gcc_location(), VAR_DECL, get_identifier_from_string(name), type_tree); DECL_CONTEXT(decl) = function->get_tree(); TREE_USED(decl) = 1; if (is_address_taken) TREE_ADDRESSABLE(decl) = 1; go_preserve_from_gc(decl); return new Bvariable(decl); } // Make a function parameter variable. Bvariable* Gcc_backend::parameter_variable(Bfunction* function, const std::string& name, Btype* btype, bool is_address_taken, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); tree decl = build_decl(location.gcc_location(), PARM_DECL, get_identifier_from_string(name), type_tree); DECL_CONTEXT(decl) = function->get_tree(); DECL_ARG_TYPE(decl) = type_tree; TREE_USED(decl) = 1; if (is_address_taken) TREE_ADDRESSABLE(decl) = 1; go_preserve_from_gc(decl); return new Bvariable(decl); } // Make a static chain variable. Bvariable* Gcc_backend::static_chain_variable(Bfunction* function, const std::string& name, Btype* btype, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); tree decl = build_decl(location.gcc_location(), PARM_DECL, get_identifier_from_string(name), type_tree); tree fndecl = function->get_tree(); DECL_CONTEXT(decl) = fndecl; DECL_ARG_TYPE(decl) = type_tree; TREE_USED(decl) = 1; DECL_ARTIFICIAL(decl) = 1; DECL_IGNORED_P(decl) = 1; TREE_READONLY(decl) = 1; struct function *f = DECL_STRUCT_FUNCTION(fndecl); if (f == NULL) { push_struct_function(fndecl); pop_cfun(); f = DECL_STRUCT_FUNCTION(fndecl); } gcc_assert(f->static_chain_decl == NULL); f->static_chain_decl = decl; DECL_STATIC_CHAIN(fndecl) = 1; go_preserve_from_gc(decl); return new Bvariable(decl); } // Make a temporary variable. Bvariable* Gcc_backend::temporary_variable(Bfunction* function, Bblock* bblock, Btype* btype, Bexpression* binit, bool is_address_taken, Location location, Bstatement** pstatement) { gcc_assert(function != NULL); tree decl = function->get_tree(); tree type_tree = btype->get_tree(); tree init_tree = binit == NULL ? NULL_TREE : binit->get_tree(); if (type_tree == error_mark_node || init_tree == error_mark_node || decl == error_mark_node) { *pstatement = this->error_statement(); return this->error_variable(); } tree var; // We can only use create_tmp_var if the type is not addressable. if (!TREE_ADDRESSABLE(type_tree)) { if (DECL_STRUCT_FUNCTION(decl) == NULL) push_struct_function(decl); else push_cfun(DECL_STRUCT_FUNCTION(decl)); var = create_tmp_var(type_tree, "GOTMP"); pop_cfun(); } else { gcc_assert(bblock != NULL); var = build_decl(location.gcc_location(), VAR_DECL, create_tmp_var_name("GOTMP"), type_tree); DECL_ARTIFICIAL(var) = 1; DECL_IGNORED_P(var) = 1; TREE_USED(var) = 1; DECL_CONTEXT(var) = decl; // We have to add this variable to the BLOCK and the BIND_EXPR. tree bind_tree = bblock->get_tree(); gcc_assert(TREE_CODE(bind_tree) == BIND_EXPR); tree block_tree = BIND_EXPR_BLOCK(bind_tree); gcc_assert(TREE_CODE(block_tree) == BLOCK); DECL_CHAIN(var) = BLOCK_VARS(block_tree); BLOCK_VARS(block_tree) = var; BIND_EXPR_VARS(bind_tree) = BLOCK_VARS(block_tree); } if (this->type_size(btype) != 0 && init_tree != NULL_TREE) DECL_INITIAL(var) = fold_convert_loc(location.gcc_location(), type_tree, init_tree); if (is_address_taken) TREE_ADDRESSABLE(var) = 1; *pstatement = this->make_statement(build1_loc(location.gcc_location(), DECL_EXPR, void_type_node, var)); // Don't initialize VAR with BINIT, but still evaluate BINIT for // its side effects. if (this->type_size(btype) == 0 && init_tree != NULL_TREE) *pstatement = this->compound_statement(this->expression_statement(function, binit), *pstatement); return new Bvariable(var); } // Create an implicit variable that is compiler-defined. This is used when // generating GC root variables and storing the values of a slice initializer. Bvariable* Gcc_backend::implicit_variable(const std::string& name, const std::string& asm_name, Btype* type, bool is_hidden, bool is_constant, bool is_common, int64_t alignment) { tree type_tree = type->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, get_identifier_from_string(name), type_tree); DECL_EXTERNAL(decl) = 0; TREE_PUBLIC(decl) = !is_hidden; TREE_STATIC(decl) = 1; TREE_USED(decl) = 1; DECL_ARTIFICIAL(decl) = 1; if (is_common) { DECL_COMMON(decl) = 1; // When the initializer for one implicit_variable refers to another, // it needs to know the visibility of the referenced struct so that // compute_reloc_for_constant will return the right value. On many // systems calling make_decl_one_only will mark the decl as weak, // which will change the return value of compute_reloc_for_constant. // We can't reliably call make_decl_one_only yet, because we don't // yet know the initializer. This issue doesn't arise in C because // Go initializers, unlike C initializers, can be indirectly // recursive. To ensure that compute_reloc_for_constant computes // the right value if some other initializer refers to this one, we // mark this symbol as weak here. We undo that below in // immutable_struct_set_init before calling mark_decl_one_only. DECL_WEAK(decl) = 1; } if (is_constant) { TREE_READONLY(decl) = 1; TREE_CONSTANT(decl) = 1; } if (alignment != 0) { SET_DECL_ALIGN(decl, alignment * BITS_PER_UNIT); DECL_USER_ALIGN(decl) = 1; } if (! asm_name.empty()) SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); go_preserve_from_gc(decl); return new Bvariable(decl); } // Set the initalizer for a variable created by implicit_variable. // This is where we finish compiling the variable. void Gcc_backend::implicit_variable_set_init(Bvariable* var, const std::string&, Btype*, bool, bool, bool is_common, Bexpression* init) { tree decl = var->get_decl(); tree init_tree; if (init == NULL) init_tree = NULL_TREE; else init_tree = init->get_tree(); if (decl == error_mark_node || init_tree == error_mark_node) return; DECL_INITIAL(decl) = init_tree; // Now that DECL_INITIAL is set, we can't call make_decl_one_only. // See the comment where DECL_WEAK is set in implicit_variable. if (is_common) { DECL_WEAK(decl) = 0; make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl)); } resolve_unique_section(decl, 2, 1); rest_of_decl_compilation(decl, 1, 0); } // Return a reference to an implicit variable defined in another package. Bvariable* Gcc_backend::implicit_variable_reference(const std::string& name, const std::string& asm_name, Btype* btype) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, get_identifier_from_string(name), type_tree); DECL_EXTERNAL(decl) = 1; TREE_PUBLIC(decl) = 1; TREE_STATIC(decl) = 0; DECL_ARTIFICIAL(decl) = 1; if (! asm_name.empty()) SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); go_preserve_from_gc(decl); return new Bvariable(decl); } // Create a named immutable initialized data structure. Bvariable* Gcc_backend::immutable_struct(const std::string& name, const std::string& asm_name, bool is_hidden, bool is_common, Btype* btype, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); tree decl = build_decl(location.gcc_location(), VAR_DECL, get_identifier_from_string(name), build_qualified_type(type_tree, TYPE_QUAL_CONST)); TREE_STATIC(decl) = 1; TREE_USED(decl) = 1; TREE_READONLY(decl) = 1; TREE_CONSTANT(decl) = 1; DECL_ARTIFICIAL(decl) = 1; if (!is_hidden) TREE_PUBLIC(decl) = 1; if (! asm_name.empty()) SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); // When the initializer for one immutable_struct refers to another, // it needs to know the visibility of the referenced struct so that // compute_reloc_for_constant will return the right value. On many // systems calling make_decl_one_only will mark the decl as weak, // which will change the return value of compute_reloc_for_constant. // We can't reliably call make_decl_one_only yet, because we don't // yet know the initializer. This issue doesn't arise in C because // Go initializers, unlike C initializers, can be indirectly // recursive. To ensure that compute_reloc_for_constant computes // the right value if some other initializer refers to this one, we // mark this symbol as weak here. We undo that below in // immutable_struct_set_init before calling mark_decl_one_only. if (is_common) DECL_WEAK(decl) = 1; // We don't call rest_of_decl_compilation until we have the // initializer. go_preserve_from_gc(decl); return new Bvariable(decl); } // Set the initializer for a variable created by immutable_struct. // This is where we finish compiling the variable. void Gcc_backend::immutable_struct_set_init(Bvariable* var, const std::string&, bool, bool is_common, Btype*, Location, Bexpression* initializer) { tree decl = var->get_decl(); tree init_tree = initializer->get_tree(); if (decl == error_mark_node || init_tree == error_mark_node) return; DECL_INITIAL(decl) = init_tree; // Now that DECL_INITIAL is set, we can't call make_decl_one_only. // See the comment where DECL_WEAK is set in immutable_struct. if (is_common) { DECL_WEAK(decl) = 0; make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl)); } // These variables are often unneeded in the final program, so put // them in their own section so that linker GC can discard them. resolve_unique_section(decl, compute_reloc_for_constant (init_tree), 1); rest_of_decl_compilation(decl, 1, 0); } // Return a reference to an immutable initialized data structure // defined in another package. Bvariable* Gcc_backend::immutable_struct_reference(const std::string& name, const std::string& asm_name, Btype* btype, Location location) { tree type_tree = btype->get_tree(); if (type_tree == error_mark_node) return this->error_variable(); gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); tree decl = build_decl(location.gcc_location(), VAR_DECL, get_identifier_from_string(name), build_qualified_type(type_tree, TYPE_QUAL_CONST)); TREE_READONLY(decl) = 1; TREE_CONSTANT(decl) = 1; DECL_ARTIFICIAL(decl) = 1; TREE_PUBLIC(decl) = 1; DECL_EXTERNAL(decl) = 1; if (! asm_name.empty()) SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); go_preserve_from_gc(decl); return new Bvariable(decl); } // Make a label. Blabel* Gcc_backend::label(Bfunction* function, const std::string& name, Location location) { tree decl; if (name.empty()) { tree func_tree = function->get_tree(); if (DECL_STRUCT_FUNCTION(func_tree) == NULL) push_struct_function(func_tree); else push_cfun(DECL_STRUCT_FUNCTION(func_tree)); decl = create_artificial_label(location.gcc_location()); pop_cfun(); } else { tree id = get_identifier_from_string(name); decl = build_decl(location.gcc_location(), LABEL_DECL, id, void_type_node); DECL_CONTEXT(decl) = function->get_tree(); } return new Blabel(decl); } // Make a statement which defines a label. Bstatement* Gcc_backend::label_definition_statement(Blabel* label) { tree lab = label->get_tree(); tree ret = fold_build1_loc(DECL_SOURCE_LOCATION(lab), LABEL_EXPR, void_type_node, lab); return this->make_statement(ret); } // Make a goto statement. Bstatement* Gcc_backend::goto_statement(Blabel* label, Location location) { tree lab = label->get_tree(); tree ret = fold_build1_loc(location.gcc_location(), GOTO_EXPR, void_type_node, lab); return this->make_statement(ret); } // Get the address of a label. Bexpression* Gcc_backend::label_address(Blabel* label, Location location) { tree lab = label->get_tree(); TREE_USED(lab) = 1; TREE_ADDRESSABLE(lab) = 1; tree ret = fold_convert_loc(location.gcc_location(), ptr_type_node, build_fold_addr_expr_loc(location.gcc_location(), lab)); return this->make_expression(ret); } // Declare or define a new function. Bfunction* Gcc_backend::function(Btype* fntype, const std::string& name, const std::string& asm_name, bool is_visible, bool is_declaration, bool is_inlinable, bool disable_split_stack, bool in_unique_section, Location location) { tree functype = fntype->get_tree(); if (functype != error_mark_node) { gcc_assert(FUNCTION_POINTER_TYPE_P(functype)); functype = TREE_TYPE(functype); } tree id = get_identifier_from_string(name); if (functype == error_mark_node || id == error_mark_node) return this->error_function(); tree decl = build_decl(location.gcc_location(), FUNCTION_DECL, id, functype); if (! asm_name.empty()) SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name)); if (is_visible) TREE_PUBLIC(decl) = 1; if (is_declaration) DECL_EXTERNAL(decl) = 1; else { tree restype = TREE_TYPE(functype); tree resdecl = build_decl(location.gcc_location(), RESULT_DECL, NULL_TREE, restype); DECL_ARTIFICIAL(resdecl) = 1; DECL_IGNORED_P(resdecl) = 1; DECL_CONTEXT(resdecl) = decl; DECL_RESULT(decl) = resdecl; } if (!is_inlinable) DECL_UNINLINABLE(decl) = 1; if (disable_split_stack) { tree attr = get_identifier("__no_split_stack__"); DECL_ATTRIBUTES(decl) = tree_cons(attr, NULL_TREE, NULL_TREE); } if (in_unique_section) resolve_unique_section(decl, 0, 1); go_preserve_from_gc(decl); return new Bfunction(decl); } // Create a statement that runs all deferred calls for FUNCTION. This should // be a statement that looks like this in C++: // finish: // try { UNDEFER; } catch { CHECK_DEFER; goto finish; } Bstatement* Gcc_backend::function_defer_statement(Bfunction* function, Bexpression* undefer, Bexpression* defer, Location location) { tree undefer_tree = undefer->get_tree(); tree defer_tree = defer->get_tree(); tree fntree = function->get_tree(); if (undefer_tree == error_mark_node || defer_tree == error_mark_node || fntree == error_mark_node) return this->error_statement(); if (DECL_STRUCT_FUNCTION(fntree) == NULL) push_struct_function(fntree); else push_cfun(DECL_STRUCT_FUNCTION(fntree)); tree stmt_list = NULL; Blabel* blabel = this->label(function, "", location); Bstatement* label_def = this->label_definition_statement(blabel); append_to_statement_list(label_def->get_tree(), &stmt_list); Bstatement* jump_stmt = this->goto_statement(blabel, location); tree jump = jump_stmt->get_tree(); tree catch_body = build2(COMPOUND_EXPR, void_type_node, defer_tree, jump); catch_body = build2(CATCH_EXPR, void_type_node, NULL, catch_body); tree try_catch = build2(TRY_CATCH_EXPR, void_type_node, undefer_tree, catch_body); append_to_statement_list(try_catch, &stmt_list); pop_cfun(); return this->make_statement(stmt_list); } // Record PARAM_VARS as the variables to use for the parameters of FUNCTION. // This will only be called for a function definition. bool Gcc_backend::function_set_parameters(Bfunction* function, const std::vector& param_vars) { tree func_tree = function->get_tree(); if (func_tree == error_mark_node) return false; tree params = NULL_TREE; tree *pp = ¶ms; for (std::vector::const_iterator pv = param_vars.begin(); pv != param_vars.end(); ++pv) { *pp = (*pv)->get_decl(); gcc_assert(*pp != error_mark_node); pp = &DECL_CHAIN(*pp); } *pp = NULL_TREE; DECL_ARGUMENTS(func_tree) = params; return true; } // Set the function body for FUNCTION using the code in CODE_BLOCK. bool Gcc_backend::function_set_body(Bfunction* function, Bstatement* code_stmt) { tree func_tree = function->get_tree(); tree code = code_stmt->get_tree(); if (func_tree == error_mark_node || code == error_mark_node) return false; DECL_SAVED_TREE(func_tree) = code; return true; } // Look up a named built-in function in the current backend implementation. // Returns NULL if no built-in function by that name exists. Bfunction* Gcc_backend::lookup_builtin(const std::string& name) { if (this->builtin_functions_.count(name) != 0) return this->builtin_functions_[name]; return NULL; } // Write the definitions for all TYPE_DECLS, CONSTANT_DECLS, // FUNCTION_DECLS, and VARIABLE_DECLS declared globally, as well as // emit early debugging information. void Gcc_backend::write_global_definitions( const std::vector& type_decls, const std::vector& constant_decls, const std::vector& function_decls, const std::vector& variable_decls) { size_t count_definitions = type_decls.size() + constant_decls.size() + function_decls.size() + variable_decls.size(); tree* defs = new tree[count_definitions]; // Convert all non-erroneous declarations into Gimple form. size_t i = 0; for (std::vector::const_iterator p = variable_decls.begin(); p != variable_decls.end(); ++p) { tree v = (*p)->get_decl(); if (v != error_mark_node) { defs[i] = v; go_preserve_from_gc(defs[i]); ++i; } } for (std::vector::const_iterator p = type_decls.begin(); p != type_decls.end(); ++p) { tree type_tree = (*p)->get_tree(); if (type_tree != error_mark_node && IS_TYPE_OR_DECL_P(type_tree)) { defs[i] = TYPE_NAME(type_tree); gcc_assert(defs[i] != NULL); go_preserve_from_gc(defs[i]); ++i; } } for (std::vector::const_iterator p = constant_decls.begin(); p != constant_decls.end(); ++p) { if ((*p)->get_tree() != error_mark_node) { defs[i] = (*p)->get_tree(); go_preserve_from_gc(defs[i]); ++i; } } for (std::vector::const_iterator p = function_decls.begin(); p != function_decls.end(); ++p) { tree decl = (*p)->get_tree(); if (decl != error_mark_node) { go_preserve_from_gc(decl); gimplify_function_tree(decl); cgraph_node::finalize_function(decl, true); defs[i] = decl; ++i; } } // Pass everything back to the middle-end. wrapup_global_declarations(defs, i); delete[] defs; } // Define a builtin function. BCODE is the builtin function code // defined by builtins.def. NAME is the name of the builtin function. // LIBNAME is the name of the corresponding library function, and is // NULL if there isn't one. FNTYPE is the type of the function. // CONST_P is true if the function has the const attribute. // NORETURN_P is true if the function has the noreturn attribute. void Gcc_backend::define_builtin(built_in_function bcode, const char* name, const char* libname, tree fntype, bool const_p, bool noreturn_p) { tree decl = add_builtin_function(name, fntype, bcode, BUILT_IN_NORMAL, libname, NULL_TREE); if (const_p) TREE_READONLY(decl) = 1; if (noreturn_p) TREE_THIS_VOLATILE(decl) = 1; set_builtin_decl(bcode, decl, true); this->builtin_functions_[name] = this->make_function(decl); if (libname != NULL) { decl = add_builtin_function(libname, fntype, bcode, BUILT_IN_NORMAL, NULL, NULL_TREE); if (const_p) TREE_READONLY(decl) = 1; if (noreturn_p) TREE_THIS_VOLATILE(decl) = 1; this->builtin_functions_[libname] = this->make_function(decl); } } // Return the backend generator. Backend* go_get_backend() { return new Gcc_backend(); }