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1 : /* Control flow graph manipulation code header file.
2 : Copyright (C) 2014-2026 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 : /* Set if the profile is computed on every edge and basic block. */
83 : bool full_profile;
84 : };
85 :
86 :
87 : extern void init_flow (function *);
88 : extern void free_cfg (function *);
89 : extern basic_block alloc_block (void);
90 : extern void link_block (basic_block, basic_block);
91 : extern void unlink_block (basic_block);
92 : extern void compact_blocks (void);
93 : extern void expunge_block (basic_block);
94 : extern edge unchecked_make_edge (basic_block, basic_block, int);
95 : extern edge cached_make_edge (sbitmap, basic_block, basic_block, int);
96 : extern edge make_edge (basic_block, basic_block, int);
97 : extern edge make_single_succ_edge (basic_block, basic_block, int);
98 : extern void remove_edge_raw (edge);
99 : extern void redirect_edge_succ (edge, basic_block);
100 : extern void redirect_edge_pred (edge, basic_block);
101 : extern void clear_bb_flags (void);
102 : extern void dump_edge_info (FILE *, edge, dump_flags_t, int);
103 : extern void debug (edge_def &ref);
104 : extern void debug (edge_def *ptr);
105 : extern void alloc_aux_for_blocks (int);
106 : extern void clear_aux_for_blocks (void);
107 : extern void free_aux_for_blocks (void);
108 : extern void alloc_aux_for_edge (edge, int);
109 : extern void alloc_aux_for_edges (int);
110 : extern void clear_aux_for_edges (void);
111 : extern void free_aux_for_edges (void);
112 : extern void debug_bb (basic_block);
113 : extern basic_block debug_bb_n (int);
114 : extern void debug_bb (basic_block, dump_flags_t);
115 : extern basic_block debug_bb_n (int, dump_flags_t);
116 : extern void dump_bb_info (FILE *, basic_block, int, dump_flags_t, bool, bool);
117 : extern void brief_dump_cfg (FILE *, dump_flags_t);
118 : extern void set_edge_probability_and_rescale_others (edge, profile_probability);
119 : extern void update_bb_profile_for_threading (basic_block, profile_count, edge);
120 : extern void scale_bbs_frequencies_profile_count (basic_block *, int,
121 : profile_count, profile_count);
122 : extern void scale_bbs_frequencies (basic_block *, int, profile_probability);
123 : extern void initialize_original_copy_tables (void);
124 : extern void reset_original_copy_tables (void);
125 : extern void free_original_copy_tables (void);
126 : extern bool original_copy_tables_initialized_p (void);
127 : extern void set_bb_original (basic_block, basic_block);
128 : extern basic_block get_bb_original (basic_block);
129 : extern void set_bb_copy (basic_block, basic_block);
130 : extern basic_block get_bb_copy (basic_block);
131 : void set_loop_copy (class loop *, class loop *);
132 : class loop *get_loop_copy (class loop *);
133 : void scale_strictly_dominated_blocks (basic_block,
134 : profile_count, profile_count);
135 :
136 : /* Generic RAII class to allocate a bit from storage of integer type T.
137 : The allocated bit is accessible as mask with the single bit set
138 : via the conversion operator to T. */
139 :
140 : template <class T>
141 : class auto_flag
142 : {
143 : public:
144 : /* static assert T is integer type of max HOST_WIDE_INT precision. */
145 443809185 : auto_flag (T *sptr)
146 : {
147 443809185 : m_sptr = sptr;
148 443809185 : int free_bit = ffs_hwi (~*sptr);
149 : /* If there are no unset bits... */
150 443809185 : if (free_bit == 0)
151 0 : gcc_unreachable ();
152 443809185 : m_flag = HOST_WIDE_INT_1U << (free_bit - 1);
153 : /* ...or if T is signed and thus the complement is sign-extended,
154 : check if we ran out of bits. We could spare us this bit
155 : if we could use C++11 std::make_unsigned<T>::type to pass
156 : ~*sptr to ffs_hwi. */
157 : if (m_flag == 0)
158 : gcc_unreachable ();
159 443809185 : gcc_checking_assert ((*sptr & m_flag) == 0);
160 443809185 : *sptr |= m_flag;
161 443809185 : }
162 443809184 : ~auto_flag ()
163 : {
164 443809184 : gcc_checking_assert ((*m_sptr & m_flag) == m_flag);
165 443809184 : *m_sptr &= ~m_flag;
166 443809184 : }
167 5728729783 : operator T () const { return m_flag; }
168 : private:
169 : T *m_sptr;
170 : T m_flag;
171 : };
172 :
173 : /* RAII class to allocate an edge flag for temporary use. You have
174 : to clear the flag from all edges when you are finished using it. */
175 :
176 61481853 : class auto_edge_flag : public auto_flag<int>
177 : {
178 : public:
179 61481854 : auto_edge_flag (function *fun)
180 61481854 : : auto_flag<int> (&fun->cfg->edge_flags_allocated) {}
181 : };
182 :
183 : /* RAII class to allocate a bb flag for temporary use. You have
184 : to clear the flag from all edges when you are finished using it. */
185 382327331 : class auto_bb_flag : public auto_flag<int>
186 : {
187 : public:
188 382327331 : auto_bb_flag (function *fun)
189 382327331 : : auto_flag<int> (&fun->cfg->bb_flags_allocated) {}
190 : };
191 :
192 : #endif /* GCC_CFG_H */
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