1 /* Flags on basic blocks and edges. 2 Copyright (C) 2012-2013 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 /* 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. */ 45 DEF_BASIC_BLOCK_FLAG(NEW, 0) 46 47 /* Set by find_unreachable_blocks. Do not rely on this being set in any 48 pass. */ 49 DEF_BASIC_BLOCK_FLAG(REACHABLE, 1) 50 51 /* Set for blocks in an irreducible loop by loop analysis. */ 52 DEF_BASIC_BLOCK_FLAG(IRREDUCIBLE_LOOP, 2) 53 54 /* Set on blocks that may actually not be single-entry single-exit block. */ 55 DEF_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. */ 59 DEF_BASIC_BLOCK_FLAG(DISABLE_SCHEDULE, 4) 60 61 /* Set on blocks that should be put in a hot section. */ 62 DEF_BASIC_BLOCK_FLAG(HOT_PARTITION, 5) 63 64 /* Set on blocks that should be put in a cold section. */ 65 DEF_BASIC_BLOCK_FLAG(COLD_PARTITION, 6) 66 67 /* Set on block that was duplicated. */ 68 DEF_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. */ 71 DEF_BASIC_BLOCK_FLAG(NON_LOCAL_GOTO_TARGET, 8) 72 73 /* Set on blocks that are in RTL format. */ 74 DEF_BASIC_BLOCK_FLAG(RTL, 9) 75 76 /* Set on blocks that are forwarder blocks. 77 Only used in cfgcleanup.c. */ 78 DEF_BASIC_BLOCK_FLAG(FORWARDER_BLOCK, 10) 79 80 /* Set on blocks that cannot be threaded through. 81 Only used in cfgcleanup.c. */ 82 DEF_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. */ 87 DEF_BASIC_BLOCK_FLAG(MODIFIED, 12) 88 89 /* A general visited flag for passes to use. */ 90 DEF_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(). */ 94 DEF_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. */ 111 DEF_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. */ 115 DEF_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. */ 121 DEF_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. */ 126 DEF_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. */ 131 DEF_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. */ 136 DEF_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. */ 140 DEF_EDGE_FLAG(DFS_BACK, 6) 141 142 /* Edge in a part of the CFG that is an irreducible loop. */ 143 DEF_EDGE_FLAG(IRREDUCIBLE_LOOP, 7) 144 145 /* Edge taken when controlling predicate is nonzero. 146 This is only used for the GIMPLE CFG. */ 147 DEF_EDGE_FLAG(TRUE_VALUE, 8) 148 149 /* Edge taken when controlling predicate is zero. 150 This is only used for the GIMPLE CFG. */ 151 DEF_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. */ 155 DEF_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. */ 159 DEF_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. */ 164 DEF_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. */ 168 DEF_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. */ 172 DEF_EDGE_FLAG(LOOP_EXIT, 14) 173 174 /* Uninstrumented edge out of a GIMPLE_TRANSACTION statement. */ 175 DEF_EDGE_FLAG(TM_UNINSTRUMENTED, 15) 176 177 /* Abort (over) edge out of a GIMPLE_TRANSACTION statement. */ 178 DEF_EDGE_FLAG(TM_ABORT, 16) 179 180 #endif 181 182 /* 183 Local variables: 184 mode:c 185 End: 186 */ 187