1 /* Control flow graph manipulation code header file. 2 Copyright (C) 2014-2022 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_CFG_H 21 #define GCC_CFG_H 22 23 #include "dominance.h" 24 25 /* What sort of profiling information we have. */ 26 enum profile_status_d 27 { 28 PROFILE_ABSENT, 29 PROFILE_GUESSED, 30 PROFILE_READ, 31 PROFILE_LAST /* Last value, used by profile streaming. */ 32 }; 33 34 /* A structure to group all the per-function control flow graph data. 35 The x_* prefixing is necessary because otherwise references to the 36 fields of this struct are interpreted as the defines for backward 37 source compatibility following the definition of this struct. */ 38 struct GTY(()) control_flow_graph { 39 /* Block pointers for the exit and entry of a function. 40 These are always the head and tail of the basic block list. */ 41 basic_block x_entry_block_ptr; 42 basic_block x_exit_block_ptr; 43 44 /* Index by basic block number, get basic block struct info. */ 45 vec<basic_block, va_gc> *x_basic_block_info; 46 47 /* Number of basic blocks in this flow graph. */ 48 int x_n_basic_blocks; 49 50 /* Number of edges in this flow graph. */ 51 int x_n_edges; 52 53 /* The first free basic block number. */ 54 int x_last_basic_block; 55 56 /* UIDs for LABEL_DECLs. */ 57 int last_label_uid; 58 59 /* Mapping of labels to their associated blocks. At present 60 only used for the gimple CFG. */ 61 vec<basic_block, va_gc> *x_label_to_block_map; 62 63 enum profile_status_d x_profile_status; 64 65 /* Whether the dominators and the postdominators are available. */ 66 enum dom_state x_dom_computed[2]; 67 68 /* Number of basic blocks in the dominance tree. */ 69 unsigned x_n_bbs_in_dom_tree[2]; 70 71 /* Maximal number of entities in the single jumptable. Used to estimate 72 final flowgraph size. */ 73 int max_jumptable_ents; 74 75 /* Maximal count of BB in function. */ 76 profile_count count_max; 77 78 /* Dynamically allocated edge/bb flags. */ 79 int edge_flags_allocated; 80 int bb_flags_allocated; 81 }; 82 83 84 extern void init_flow (function *); 85 extern void free_cfg (function *); 86 extern basic_block alloc_block (void); 87 extern void link_block (basic_block, basic_block); 88 extern void unlink_block (basic_block); 89 extern void compact_blocks (void); 90 extern void expunge_block (basic_block); 91 extern edge unchecked_make_edge (basic_block, basic_block, int); 92 extern edge cached_make_edge (sbitmap, basic_block, basic_block, int); 93 extern edge make_edge (basic_block, basic_block, int); 94 extern edge make_single_succ_edge (basic_block, basic_block, int); 95 extern void remove_edge_raw (edge); 96 extern void redirect_edge_succ (edge, basic_block); 97 extern void redirect_edge_pred (edge, basic_block); 98 extern void clear_bb_flags (void); 99 extern void dump_edge_info (FILE *, edge, dump_flags_t, int); 100 extern void debug (edge_def &ref); 101 extern void debug (edge_def *ptr); 102 extern void alloc_aux_for_blocks (int); 103 extern void clear_aux_for_blocks (void); 104 extern void free_aux_for_blocks (void); 105 extern void alloc_aux_for_edge (edge, int); 106 extern void alloc_aux_for_edges (int); 107 extern void clear_aux_for_edges (void); 108 extern void free_aux_for_edges (void); 109 extern void debug_bb (basic_block); 110 extern basic_block debug_bb_n (int); 111 extern void debug_bb (basic_block, dump_flags_t); 112 extern basic_block debug_bb_n (int, dump_flags_t); 113 extern void dump_bb_info (FILE *, basic_block, int, dump_flags_t, bool, bool); 114 extern void brief_dump_cfg (FILE *, dump_flags_t); 115 extern void update_bb_profile_for_threading (basic_block, profile_count, edge); 116 extern void scale_bbs_frequencies_profile_count (basic_block *, int, 117 profile_count, profile_count); 118 extern void scale_bbs_frequencies (basic_block *, int, profile_probability); 119 extern void initialize_original_copy_tables (void); 120 extern void reset_original_copy_tables (void); 121 extern void free_original_copy_tables (void); 122 extern bool original_copy_tables_initialized_p (void); 123 extern void set_bb_original (basic_block, basic_block); 124 extern basic_block get_bb_original (basic_block); 125 extern void set_bb_copy (basic_block, basic_block); 126 extern basic_block get_bb_copy (basic_block); 127 void set_loop_copy (class loop *, class loop *); 128 class loop *get_loop_copy (class loop *); 129 130 /* Generic RAII class to allocate a bit from storage of integer type T. 131 The allocated bit is accessible as mask with the single bit set 132 via the conversion operator to T. */ 133 134 template <class T> 135 class auto_flag 136 { 137 public: 138 /* static assert T is integer type of max HOST_WIDE_INT precision. */ auto_flag(T * sptr)139 auto_flag (T *sptr) 140 { 141 m_sptr = sptr; 142 int free_bit = ffs_hwi (~*sptr); 143 /* If there are no unset bits... */ 144 if (free_bit == 0) 145 gcc_unreachable (); 146 m_flag = HOST_WIDE_INT_1U << (free_bit - 1); 147 /* ...or if T is signed and thus the complement is sign-extended, 148 check if we ran out of bits. We could spare us this bit 149 if we could use C++11 std::make_unsigned<T>::type to pass 150 ~*sptr to ffs_hwi. */ 151 if (m_flag == 0) 152 gcc_unreachable (); 153 gcc_checking_assert ((*sptr & m_flag) == 0); 154 *sptr |= m_flag; 155 } ~auto_flag()156 ~auto_flag () 157 { 158 gcc_checking_assert ((*m_sptr & m_flag) == m_flag); 159 *m_sptr &= ~m_flag; 160 } T()161 operator T () const { return m_flag; } 162 private: 163 T *m_sptr; 164 T m_flag; 165 }; 166 167 /* RAII class to allocate an edge flag for temporary use. You have 168 to clear the flag from all edges when you are finished using it. */ 169 170 class auto_edge_flag : public auto_flag<int> 171 { 172 public: auto_edge_flag(function * fun)173 auto_edge_flag (function *fun) 174 : auto_flag<int> (&fun->cfg->edge_flags_allocated) {} 175 }; 176 177 /* RAII class to allocate a bb flag for temporary use. You have 178 to clear the flag from all edges when you are finished using it. */ 179 class auto_bb_flag : public auto_flag<int> 180 { 181 public: auto_bb_flag(function * fun)182 auto_bb_flag (function *fun) 183 : auto_flag<int> (&fun->cfg->bb_flags_allocated) {} 184 }; 185 186 #endif /* GCC_CFG_H */ 187