1 /* Flags on basic blocks and edges.
2 Copyright (C
) 2012 Free Software Foundation
, Inc.
4 This file is part of GCC.
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
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
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
/>.
*/
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.
*/
24 #if
!defined(DEF_BASIC_BLOCK_FLAG
) && !defined(DEF_EDGE_FLAG
)
25 #error
"You must define DEF_BASIC_BLOCK_FLAG or DEF_EDGE_FLAG"
28 #ifdef DEF_BASIC_BLOCK_FLAG
30 /* Masks for basic_block.flags.
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
).
38 BB_HOT_PARTITION and BB_COLD_PARTITION should be preserved throughout
39 the compilation
, so they are never cleared.
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.
*/
44 /* Only set on blocks that have just been created by create_bb.
*/
45 DEF_BASIC_BLOCK_FLAG(NEW, 0)
47 /* Set by find_unreachable_blocks. Do not rely on this being set in any
49 DEF_BASIC_BLOCK_FLAG(REACHABLE
, 1)
51 /* Set for blocks in an irreducible loop by loop analysis.
*/
52 DEF_BASIC_BLOCK_FLAG(IRREDUCIBLE_LOOP
, 2)
54 /* Set on blocks that may actually not be single
-entry single
-exit block.
*/
55 DEF_BASIC_BLOCK_FLAG(SUPERBLOCK
, 3)
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.
*/
59 DEF_BASIC_BLOCK_FLAG(DISABLE_SCHEDULE
, 4)
61 /* Set on blocks that should be put in a hot section.
*/
62 DEF_BASIC_BLOCK_FLAG(HOT_PARTITION
, 5)
64 /* Set on blocks that should be put in a cold section.
*/
65 DEF_BASIC_BLOCK_FLAG(COLD_PARTITION
, 6)
67 /* Set on block that was duplicated.
*/
68 DEF_BASIC_BLOCK_FLAG(DUPLICATED
, 7)
70 /* Set if the label at the top of this block is the target of a non
-local goto.
*/
71 DEF_BASIC_BLOCK_FLAG(NON_LOCAL_GOTO_TARGET
, 8)
73 /* Set on blocks that are in RTL format.
*/
74 DEF_BASIC_BLOCK_FLAG(RTL
, 9)
76 /* Set on blocks that are forwarder blocks.
77 Only used in cfgcleanup.c.
*/
78 DEF_BASIC_BLOCK_FLAG(FORWARDER_BLOCK
, 10)
80 /* Set on blocks that cannot be threaded through.
81 Only used in cfgcleanup.c.
*/
82 DEF_BASIC_BLOCK_FLAG(NONTHREADABLE_BLOCK
, 11)
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.
*/
87 DEF_BASIC_BLOCK_FLAG(MODIFIED
, 12)
89 /* A general visited flag for passes to use.
*/
90 DEF_BASIC_BLOCK_FLAG(VISITED
, 13)
92 /* Set on blocks that are in a transaction. This is calculated on
93 demand
, and is available after calling
compute_transaction_bits().
*/
94 DEF_BASIC_BLOCK_FLAG(IN_TRANSACTION
, 14)
100 /* Masks for edge.flags.
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
).
*/
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.
*/
111 DEF_EDGE_FLAG(FALLTHRU
, 0)
113 /* Strange flow
, like a computed jump or exception handling. Usually
114 this means that the edge cannot be split.
*/
115 DEF_EDGE_FLAG(ABNORMAL
, 1)
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.
*/
121 DEF_EDGE_FLAG(ABNORMAL_CALL
, 2)
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.
*/
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.
*/
131 DEF_EDGE_FLAG(PRESERVE
, 4)
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.
*/
136 DEF_EDGE_FLAG(FAKE
, 5)
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.
*/
140 DEF_EDGE_FLAG(DFS_BACK
, 6)
142 /* Edge in a part of the CFG that is an irreducible loop.
*/
143 DEF_EDGE_FLAG(IRREDUCIBLE_LOOP
, 7)
145 /* Edge taken when controlling predicate is nonzero.
146 This is only used for the GIMPLE CFG.
*/
147 DEF_EDGE_FLAG(TRUE_VALUE
, 8)
149 /* Edge taken when controlling predicate is zero.
150 This is only used for the GIMPLE CFG.
*/
151 DEF_EDGE_FLAG(FALSE_VALUE
, 9)
153 /* Edge is executable. This is only used in GIMPLE SSA
-CCP and VRP.
154 This is only used for the GIMPLE CFG.
*/
155 DEF_EDGE_FLAG(EXECUTABLE
, 10)
157 /* Edge crosses between hot and cold sections
, when we do partitioning.
158 This flag is only used for the RTL CFG.
*/
159 DEF_EDGE_FLAG(CROSSING
, 11)
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.
*/
164 DEF_EDGE_FLAG(SIBCALL
, 12)
166 /* Candidate for straight line flow. Only used in bb
-reorder.c.
167 This flag is only used for the RTL CFG.
*/
168 DEF_EDGE_FLAG(CAN_FALLTHRU
, 13)
170 /* Exit of a loop. This is only used in ifcvt.c.
171 This flag is only used for the RTL CFG.
*/
172 DEF_EDGE_FLAG(LOOP_EXIT
, 14)
174 /* Uninstrumented edge out of a GIMPLE_TRANSACTION statement.
*/
175 DEF_EDGE_FLAG(TM_UNINSTRUMENTED
, 15)
177 /* Abort (over
) edge out of a GIMPLE_TRANSACTION statement.
*/
178 DEF_EDGE_FLAG(TM_ABORT
, 16)