1/* Flags on basic blocks and edges.
2 Copyright (C) 2012-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20/* This file defines flags that may appear on basic blocks or on
21 edges. Source files define DEF_BASIC_BLOCK_FLAG or DEF_EDGE_FLAG
22 appropriately before including this file. */
23
24#if !defined(DEF_BASIC_BLOCK_FLAG) && !defined(DEF_EDGE_FLAG)
25#error "You must define DEF_BASIC_BLOCK_FLAG or DEF_EDGE_FLAG"
26#endif
27
28#ifdef DEF_BASIC_BLOCK_FLAG
29
30/* Masks for basic_block.flags.
31
32 The format of this file is: DEF_BASIC_BLOCK_FLAG(NAME, IDX).
33 NAME is the name of the basic block flag. A flag BB_#NAME will be
34 created and the name is used in dump_edge_info.
35 IDX is a sequence number that is used to determine the value
36 of the flag, which is 1 << IDX).
37
38 BB_HOT_PARTITION and BB_COLD_PARTITION should be preserved throughout
39 the compilation, so they are never cleared.
40
41 All other flags may be cleared by clear_bb_flags(). It is generally
42 a bad idea to rely on any flags being up-to-date. */
43
44/* Only set on blocks that have just been created by create_bb. */
45DEF_BASIC_BLOCK_FLAG(NEW, 0)
46
47/* Set by find_unreachable_blocks. Do not rely on this being set in any
48 pass. */
49DEF_BASIC_BLOCK_FLAG(REACHABLE, 1)
50
51/* Set for blocks in an irreducible loop by loop analysis. */
52DEF_BASIC_BLOCK_FLAG(IRREDUCIBLE_LOOP, 2)
53
54/* Set on blocks that may actually not be single-entry single-exit block. */
55DEF_BASIC_BLOCK_FLAG(SUPERBLOCK, 3)
56
57/* Set on basic blocks that the scheduler should not touch. This is used
58 by SMS to prevent other schedulers from messing with the loop schedule. */
59DEF_BASIC_BLOCK_FLAG(DISABLE_SCHEDULE, 4)
60
61/* Set on blocks that should be put in a hot section. */
62DEF_BASIC_BLOCK_FLAG(HOT_PARTITION, 5)
63
64/* Set on blocks that should be put in a cold section. */
65DEF_BASIC_BLOCK_FLAG(COLD_PARTITION, 6)
66
67/* Set on block that was duplicated. */
68DEF_BASIC_BLOCK_FLAG(DUPLICATED, 7)
69
70/* Set if the label at the top of this block is the target of a non-local goto. */
71DEF_BASIC_BLOCK_FLAG(NON_LOCAL_GOTO_TARGET, 8)
72
73/* Set on blocks that are in RTL format. */
74DEF_BASIC_BLOCK_FLAG(RTL, 9)
75
76/* Set on blocks that are forwarder blocks.
77 Only used in cfgcleanup.c. */
78DEF_BASIC_BLOCK_FLAG(FORWARDER_BLOCK, 10)
79
80/* Set on blocks that cannot be threaded through.
81 Only used for jump threading. */
82DEF_BASIC_BLOCK_FLAG(NONTHREADABLE_BLOCK, 11)
83
84/* Set on blocks that were modified in some way. This bit is set in
85 df_set_bb_dirty, but not cleared by df_analyze, so it can be used
86 to test whether a block has been modified prior to a df_analyze call. */
87DEF_BASIC_BLOCK_FLAG(MODIFIED, 12)
88
89/* A general visited flag for passes to use. */
90DEF_BASIC_BLOCK_FLAG(VISITED, 13)
91
92/* Set on blocks that are in a transaction. This is calculated on
93 demand, and is available after calling compute_transaction_bits(). */
94DEF_BASIC_BLOCK_FLAG(IN_TRANSACTION, 14)
95
96#endif
97
98#ifdef DEF_EDGE_FLAG
99
100/* Masks for edge.flags.
101
102 The format of this file is: DEF_EDGE_FLAG(NAME, IDX, STRING).
103 NAME is the name of the edge flag. A flag EDGE_#NAME will be
104 created and the name is used in dump_edge_info.
105 IDX is a sequence number that is used to determine the value
106 of the flag, which is 1 << IDX). */
107
108/* 'Straight line' flow. In GIMPLE and in cfglayout mode, all normal
109 edges are fallthru edges. In cfgrtl mode, this flag really means
110 that control flow falls through to the next basic block in the line. */
111DEF_EDGE_FLAG(FALLTHRU, 0)
112
113/* Strange flow, like a computed jump or exception handling. Usually
114 this means that the edge cannot be split. */
115DEF_EDGE_FLAG(ABNORMAL, 1)
116
117/* Edge out of a basic block that ends with a CALL_INSN with abnormal
118 exit, like an exception or a non-local goto.
119 ABNORMAL_CALL edges also have ABNORMAL set.
120 This flag is only used for the RTL CFG. */
121DEF_EDGE_FLAG(ABNORMAL_CALL, 2)
122
123/* Exception edge. Exception handling edges represent possible control
124 transfers from a trapping instruction to an exception handler.
125 EH edges also have ABNORMAL set for the RTL CFG. */
126DEF_EDGE_FLAG(EH, 3)
127
128/* Never merge blocks via this edge. This is used for exception handling,
129 to prevent merging away edges to the post-landing-pad basic block.
130 This flag is only used for the RTL CFG. */
131DEF_EDGE_FLAG(PRESERVE, 4)
132
133/* Not a real edge. This is used to connect parts of the CFG that do
134 not halt, such as infinite loops and noreturn functions, to the
135 EXIT_BLOCK, so that traversing of the reverse CFG is possible. */
136DEF_EDGE_FLAG(FAKE, 5)
137
138/* A back edge, marked in a depth-first search of the CFG. Back edges
139 are hints that this edge may be part of a loop in the CFG. */
140DEF_EDGE_FLAG(DFS_BACK, 6)
141
142/* Edge in a part of the CFG that is an irreducible loop. */
143DEF_EDGE_FLAG(IRREDUCIBLE_LOOP, 7)
144
145/* Edge taken when controlling predicate is nonzero.
146 This is only used for the GIMPLE CFG. */
147DEF_EDGE_FLAG(TRUE_VALUE, 8)
148
149/* Edge taken when controlling predicate is zero.
150 This is only used for the GIMPLE CFG. */
151DEF_EDGE_FLAG(FALSE_VALUE, 9)
152
153/* Edge is executable. This is only used in GIMPLE SSA-CCP and VRP.
154 This is only used for the GIMPLE CFG. */
155DEF_EDGE_FLAG(EXECUTABLE, 10)
156
157/* Edge crosses between hot and cold sections, when we do partitioning.
158 This flag is only used for the RTL CFG. */
159DEF_EDGE_FLAG(CROSSING, 11)
160
161/* Edge from a sibcall CALL_INSN to exit.
162 SIBCALL edges also have ABNORMAL set.
163 This flag is only used for the RTL CFG. */
164DEF_EDGE_FLAG(SIBCALL, 12)
165
166/* Candidate for straight line flow. Only used in bb-reorder.c.
167 This flag is only used for the RTL CFG. */
168DEF_EDGE_FLAG(CAN_FALLTHRU, 13)
169
170/* Exit of a loop. This is only used in ifcvt.c.
171 This flag is only used for the RTL CFG. */
172DEF_EDGE_FLAG(LOOP_EXIT, 14)
173
174/* Uninstrumented edge out of a GIMPLE_TRANSACTION statement. */
175DEF_EDGE_FLAG(TM_UNINSTRUMENTED, 15)
176
177/* Abort (over) edge out of a GIMPLE_TRANSACTION statement. */
178DEF_EDGE_FLAG(TM_ABORT, 16)
179
180/* An edge we should ignore. It should be entirely local to
181 passes. ie, it is never set on any edge upon the completion
182 of any pass. */
183DEF_EDGE_FLAG(IGNORE, 17)
184
185#endif
186
187/*
188Local variables:
189mode:c
190End:
191*/
192