/* Interprocedural semantic function equality pass Copyright (C) 2014-2024 Free Software Foundation, Inc. Contributed by Jan Hubicka and Martin Liska 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 . */ /* Gimple identical code folding (class func_checker) is an infrastructure capable of comparing two given functions. The class compares every gimple statement and uses many dictionaries to map source and target SSA_NAMEs, declarations and other components. To use the infrastructure, create an instance of func_checker and call a comparison function based on type of gimple statement. */ /* Prints string STRING to a FILE with a given number of SPACE_COUNT. */ #define FPUTS_SPACES(file, space_count, string) \ fprintf (file, "%*s" string, space_count, " "); /* fprintf function wrapper that transforms given FORMAT to follow given number for SPACE_COUNT and call fprintf for a FILE. */ #define FPRINTF_SPACES(file, space_count, format, ...) \ fprintf (file, "%*s" format, space_count, " ", ##__VA_ARGS__); /* Logs a MESSAGE to dump_file if exists and returns false. FUNC is name of function and LINE is location in the source file. */ inline bool return_false_with_message_1 (const char *message, const char *filename, const char *func, unsigned int line) { if (dump_file && (dump_flags & TDF_DETAILS)) fprintf (dump_file, " false returned: '%s' in %s at %s:%u\n", message, func, filename, line); return false; } /* Logs a MESSAGE to dump_file if exists and returns false. */ #define return_false_with_msg(message) \ return_false_with_message_1 (message, __FILE__, __func__, __LINE__) /* Return false and log that false value is returned. */ #define return_false() return_false_with_msg ("") /* Logs return value if RESULT is false. FUNC is name of function and LINE is location in the source file. */ inline bool return_with_result (bool result, const char *filename, const char *func, unsigned int line) { if (!result && dump_file && (dump_flags & TDF_DETAILS)) fprintf (dump_file, " false returned: '' in %s at %s:%u\n", func, filename, line); return result; } /* Logs return value if RESULT is false. */ #define return_with_debug(result) return_with_result \ (result, __FILE__, __func__, __LINE__) /* Verbose logging function logging statements S1 and S2 of a CODE. FUNC is name of function and LINE is location in the source file. */ inline bool return_different_stmts_1 (gimple *s1, gimple *s2, const char *code, const char *func, unsigned int line) { if (dump_file && (dump_flags & TDF_DETAILS)) { fprintf (dump_file, " different statement for code: %s (%s:%u):\n", code, func, line); print_gimple_stmt (dump_file, s1, 3, TDF_DETAILS); print_gimple_stmt (dump_file, s2, 3, TDF_DETAILS); } return false; } /* Verbose logging function logging statements S1 and S2 of a CODE. */ #define return_different_stmts(s1, s2, code) \ return_different_stmts_1 (s1, s2, code, __func__, __LINE__) namespace ipa_icf_gimple { /* Basic block struct for semantic equality pass. */ class sem_bb { public: sem_bb (basic_block bb_, unsigned nondbg_stmt_count_, unsigned edge_count_): bb (bb_), nondbg_stmt_count (nondbg_stmt_count_), edge_count (edge_count_) {} /* Basic block the structure belongs to. */ basic_block bb; /* Number of non-debug statements in the basic block. */ unsigned nondbg_stmt_count; /* Number of edges connected to the block. */ unsigned edge_count; }; /* A class aggregating all connections and semantic equivalents for a given pair of semantic function candidates. */ class func_checker : ao_compare { public: /* Default constructor. */ func_checker (): m_source_func_decl (NULL_TREE), m_target_func_decl (NULL_TREE), m_ignored_source_nodes (NULL), m_ignored_target_nodes (NULL), m_ignore_labels (false), m_tbaa (true) { m_source_ssa_names.create (0); m_target_ssa_names.create (0); } /* Initialize internal structures for a given SOURCE_FUNC_DECL and TARGET_FUNC_DECL. Strict polymorphic comparison is processed if an option COMPARE_POLYMORPHIC is true. For special cases, one can set IGNORE_LABELS to skip label comparison. Similarly, IGNORE_SOURCE_DECLS and IGNORE_TARGET_DECLS are sets of declarations that can be skipped. */ func_checker (tree source_func_decl, tree target_func_decl, bool ignore_labels = false, bool tbaa = true, hash_set *ignored_source_nodes = NULL, hash_set *ignored_target_nodes = NULL); /* Memory release routine. */ virtual ~func_checker (); /* Function visits all gimple labels and creates corresponding mapping between basic blocks and labels. */ void parse_labels (sem_bb *bb); /* Basic block equivalence comparison function that returns true if basic blocks BB1 and BB2 correspond. */ bool compare_bb (sem_bb *bb1, sem_bb *bb2); /* Verifies that trees T1 and T2 are equivalent from perspective of ICF. */ bool compare_ssa_name (const_tree t1, const_tree t2); /* Verification function for edges E1 and E2. */ bool compare_edge (edge e1, edge e2); /* Verifies for given GIMPLEs S1 and S2 that call statements are semantically equivalent. */ bool compare_gimple_call (gcall *s1, gcall *s2); /* Verifies for given GIMPLEs S1 and S2 that assignment statements are semantically equivalent. */ bool compare_gimple_assign (gimple *s1, gimple *s2); /* Verifies for given GIMPLEs S1 and S2 that condition statements are semantically equivalent. */ bool compare_gimple_cond (gimple *s1, gimple *s2); /* Verifies for given GIMPLE_LABEL stmts S1 and S2 that label statements are semantically equivalent. */ bool compare_gimple_label (const glabel *s1, const glabel *s2); /* Verifies for given GIMPLE_SWITCH stmts S1 and S2 that switch statements are semantically equivalent. */ bool compare_gimple_switch (const gswitch *s1, const gswitch *s2); /* Verifies for given GIMPLE_RETURN stmts S1 and S2 that return statements are semantically equivalent. */ bool compare_gimple_return (const greturn *s1, const greturn *s2); /* Verifies for given GIMPLEs S1 and S2 that goto statements are semantically equivalent. */ bool compare_gimple_goto (gimple *s1, gimple *s2); /* Verifies for given GIMPLE_RESX stmts S1 and S2 that resx statements are semantically equivalent. */ bool compare_gimple_resx (const gresx *s1, const gresx *s2); /* Verifies for given GIMPLE_ASM stmts S1 and S2 that ASM statements are equivalent. For the beginning, the pass only supports equality for '__asm__ __volatile__ ("", "", "", "memory")'. */ bool compare_gimple_asm (const gasm *s1, const gasm *s2); /* Verification function for declaration trees T1 and T2. */ bool compare_decl (const_tree t1, const_tree t2); /* Compute hash map MAP that determines loads and stores of STMT. */ enum operand_access_type {OP_MEMORY, OP_NORMAL}; typedef hash_set operand_access_type_map; /* Function responsible for comparison of various operands T1 and T2. If these components, from functions FUNC1 and FUNC2, are equal, true is returned. */ bool compare_operand (tree t1, tree t2, operand_access_type type); /* Compares GIMPLE ASM inputs (or outputs) where we iterate tree chain and compare both TREE_PURPOSEs and TREE_VALUEs. */ bool compare_asm_inputs_outputs (tree t1, tree t2, operand_access_type_map *map); /* Verifies that trees T1 and T2, representing function declarations are equivalent from perspective of ICF. */ bool compare_function_decl (tree t1, tree t2); /* Verifies that trees T1 and T2 do correspond. */ bool compare_variable_decl (const_tree t1, const_tree t2); /* Compare loop information for basic blocks BB1 and BB2. */ bool compare_loops (basic_block bb1, basic_block bb2); /* Return true if types are compatible for polymorphic call analysis. COMPARE_PTR indicates if polymorphic type comparison should be done for pointers, too. */ static bool compatible_polymorphic_types_p (tree t1, tree t2, bool compare_ptr); /* Return true if types are compatible from perspective of ICF. FIRST_ARGUMENT indicates if the comparison is called for first parameter of a function. */ static bool compatible_types_p (tree t1, tree t2); /* Compute hash map determining access types of operands. */ static void classify_operands (const gimple *stmt, operand_access_type_map *map); /* Return access type of a given operand. */ static operand_access_type get_operand_access_type (operand_access_type_map *map, tree); private: /* Vector mapping source SSA names to target ones. */ vec m_source_ssa_names; /* Vector mapping target SSA names to source ones. */ vec m_target_ssa_names; /* Source TREE function declaration. */ tree m_source_func_decl; /* Target TREE function declaration. */ tree m_target_func_decl; /* Source symbol nodes that should be skipped by declaration comparison. */ hash_set *m_ignored_source_nodes; /* Target symbol nodes that should be skipped by declaration comparison. */ hash_set *m_ignored_target_nodes; /* Source to target edge map. */ hash_map m_edge_map; /* Source to target declaration map. */ hash_map m_decl_map; /* Label to basic block index mapping. */ hash_map m_label_bb_map; /* Flag if ignore labels in comparison. */ bool m_ignore_labels; /* Flag if we should compare type based alias analysis info. */ bool m_tbaa; public: /* Return true if two operands are equal. The flags fields can be used to specify OEP flags described above. */ bool operand_equal_p (const_tree, const_tree, unsigned int flags) final override; /* Generate a hash value for an expression. This can be used iteratively by passing a previous result as the HSTATE argument. */ void hash_operand (const_tree, inchash::hash &, unsigned flags) final override; void hash_operand (const_tree, inchash::hash &, unsigned flags, operand_access_type access); }; } // ipa_icf_gimple namespace