1 |
38 |
julius |
/* Miscellaneous SSA utility functions.
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2 |
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Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
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3 |
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4 |
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This file is part of GCC.
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5 |
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6 |
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GCC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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11 |
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GCC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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20 |
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#include "config.h"
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21 |
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#include "system.h"
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22 |
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#include "coretypes.h"
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23 |
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#include "tm.h"
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24 |
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#include "tree.h"
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25 |
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#include "flags.h"
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26 |
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#include "rtl.h"
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27 |
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#include "tm_p.h"
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28 |
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#include "ggc.h"
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29 |
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#include "langhooks.h"
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30 |
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#include "hard-reg-set.h"
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31 |
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#include "basic-block.h"
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32 |
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#include "output.h"
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33 |
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#include "expr.h"
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34 |
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#include "function.h"
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35 |
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#include "diagnostic.h"
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36 |
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#include "bitmap.h"
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37 |
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#include "pointer-set.h"
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38 |
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#include "tree-flow.h"
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39 |
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#include "tree-gimple.h"
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40 |
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#include "tree-inline.h"
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41 |
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#include "varray.h"
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42 |
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#include "timevar.h"
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43 |
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#include "hashtab.h"
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44 |
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#include "tree-dump.h"
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45 |
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#include "tree-pass.h"
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46 |
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#include "toplev.h"
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47 |
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48 |
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/* Remove the corresponding arguments from the PHI nodes in E's
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49 |
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destination block and redirect it to DEST. Return redirected edge.
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50 |
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The list of removed arguments is stored in PENDING_STMT (e). */
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51 |
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52 |
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edge
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53 |
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ssa_redirect_edge (edge e, basic_block dest)
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54 |
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{
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55 |
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tree phi;
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56 |
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tree list = NULL, *last = &list;
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57 |
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tree src, dst, node;
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58 |
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59 |
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/* Remove the appropriate PHI arguments in E's destination block. */
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60 |
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for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
|
61 |
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{
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62 |
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if (PHI_ARG_DEF (phi, e->dest_idx) == NULL_TREE)
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63 |
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continue;
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64 |
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65 |
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src = PHI_ARG_DEF (phi, e->dest_idx);
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66 |
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dst = PHI_RESULT (phi);
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67 |
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node = build_tree_list (dst, src);
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68 |
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*last = node;
|
69 |
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last = &TREE_CHAIN (node);
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70 |
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}
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71 |
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72 |
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e = redirect_edge_succ_nodup (e, dest);
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73 |
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PENDING_STMT (e) = list;
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74 |
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75 |
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return e;
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76 |
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}
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77 |
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|
78 |
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/* Add PHI arguments queued in PENDINT_STMT list on edge E to edge
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79 |
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E->dest. */
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80 |
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81 |
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void
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82 |
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flush_pending_stmts (edge e)
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83 |
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{
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84 |
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tree phi, arg;
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85 |
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86 |
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if (!PENDING_STMT (e))
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87 |
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return;
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88 |
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89 |
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for (phi = phi_nodes (e->dest), arg = PENDING_STMT (e);
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90 |
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phi;
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91 |
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phi = PHI_CHAIN (phi), arg = TREE_CHAIN (arg))
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92 |
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{
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93 |
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tree def = TREE_VALUE (arg);
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94 |
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add_phi_arg (phi, def, e);
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95 |
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}
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96 |
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97 |
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PENDING_STMT (e) = NULL;
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98 |
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}
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99 |
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100 |
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/* Return true if SSA_NAME is malformed and mark it visited.
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101 |
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102 |
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IS_VIRTUAL is true if this SSA_NAME was found inside a virtual
|
103 |
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operand. */
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104 |
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105 |
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static bool
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106 |
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verify_ssa_name (tree ssa_name, bool is_virtual)
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107 |
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{
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108 |
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if (TREE_CODE (ssa_name) != SSA_NAME)
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109 |
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{
|
110 |
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error ("expected an SSA_NAME object");
|
111 |
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return true;
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112 |
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}
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113 |
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114 |
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if (TREE_TYPE (ssa_name) != TREE_TYPE (SSA_NAME_VAR (ssa_name)))
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115 |
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{
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116 |
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error ("type mismatch between an SSA_NAME and its symbol");
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117 |
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return true;
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118 |
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}
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119 |
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120 |
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if (SSA_NAME_IN_FREE_LIST (ssa_name))
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121 |
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{
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122 |
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error ("found an SSA_NAME that had been released into the free pool");
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123 |
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return true;
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124 |
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}
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125 |
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126 |
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if (is_virtual && is_gimple_reg (ssa_name))
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127 |
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{
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128 |
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error ("found a virtual definition for a GIMPLE register");
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129 |
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return true;
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130 |
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}
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131 |
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132 |
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if (!is_virtual && !is_gimple_reg (ssa_name))
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133 |
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{
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134 |
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error ("found a real definition for a non-register");
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135 |
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return true;
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136 |
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}
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137 |
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138 |
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if (is_virtual && var_ann (SSA_NAME_VAR (ssa_name))
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139 |
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&& get_subvars_for_var (SSA_NAME_VAR (ssa_name)) != NULL)
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140 |
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{
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141 |
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error ("found real variable when subvariables should have appeared");
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142 |
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return true;
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143 |
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}
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144 |
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|
145 |
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return false;
|
146 |
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}
|
147 |
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|
148 |
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|
149 |
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/* Return true if the definition of SSA_NAME at block BB is malformed.
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150 |
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|
151 |
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STMT is the statement where SSA_NAME is created.
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152 |
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153 |
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DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME
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154 |
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version numbers. If DEFINITION_BLOCK[SSA_NAME_VERSION] is set,
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155 |
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it means that the block in that array slot contains the
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156 |
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definition of SSA_NAME.
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157 |
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158 |
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IS_VIRTUAL is true if SSA_NAME is created by a V_MAY_DEF or a
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159 |
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V_MUST_DEF. */
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160 |
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161 |
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static bool
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162 |
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verify_def (basic_block bb, basic_block *definition_block, tree ssa_name,
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163 |
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tree stmt, bool is_virtual)
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164 |
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{
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165 |
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if (verify_ssa_name (ssa_name, is_virtual))
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166 |
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goto err;
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167 |
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168 |
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if (definition_block[SSA_NAME_VERSION (ssa_name)])
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169 |
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{
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170 |
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error ("SSA_NAME created in two different blocks %i and %i",
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171 |
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definition_block[SSA_NAME_VERSION (ssa_name)]->index, bb->index);
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172 |
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goto err;
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173 |
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}
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174 |
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175 |
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definition_block[SSA_NAME_VERSION (ssa_name)] = bb;
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176 |
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|
177 |
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if (SSA_NAME_DEF_STMT (ssa_name) != stmt)
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178 |
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{
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179 |
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error ("SSA_NAME_DEF_STMT is wrong");
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180 |
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fprintf (stderr, "Expected definition statement:\n");
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181 |
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print_generic_stmt (stderr, SSA_NAME_DEF_STMT (ssa_name), TDF_VOPS);
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182 |
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fprintf (stderr, "\nActual definition statement:\n");
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183 |
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print_generic_stmt (stderr, stmt, TDF_VOPS);
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184 |
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goto err;
|
185 |
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}
|
186 |
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187 |
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return false;
|
188 |
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|
189 |
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err:
|
190 |
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|
fprintf (stderr, "while verifying SSA_NAME ");
|
191 |
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|
print_generic_expr (stderr, ssa_name, 0);
|
192 |
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fprintf (stderr, " in statement\n");
|
193 |
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print_generic_stmt (stderr, stmt, TDF_VOPS);
|
194 |
|
|
|
195 |
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|
return true;
|
196 |
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|
}
|
197 |
|
|
|
198 |
|
|
|
199 |
|
|
/* Return true if the use of SSA_NAME at statement STMT in block BB is
|
200 |
|
|
malformed.
|
201 |
|
|
|
202 |
|
|
DEF_BB is the block where SSA_NAME was found to be created.
|
203 |
|
|
|
204 |
|
|
IDOM contains immediate dominator information for the flowgraph.
|
205 |
|
|
|
206 |
|
|
CHECK_ABNORMAL is true if the caller wants to check whether this use
|
207 |
|
|
is flowing through an abnormal edge (only used when checking PHI
|
208 |
|
|
arguments).
|
209 |
|
|
|
210 |
|
|
IS_VIRTUAL is true if SSA_NAME is created by a V_MAY_DEF or a
|
211 |
|
|
V_MUST_DEF.
|
212 |
|
|
|
213 |
|
|
If NAMES_DEFINED_IN_BB is not NULL, it contains a bitmap of ssa names
|
214 |
|
|
that are defined before STMT in basic block BB. */
|
215 |
|
|
|
216 |
|
|
static bool
|
217 |
|
|
verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p,
|
218 |
|
|
tree stmt, bool check_abnormal, bool is_virtual,
|
219 |
|
|
bitmap names_defined_in_bb)
|
220 |
|
|
{
|
221 |
|
|
bool err = false;
|
222 |
|
|
tree ssa_name = USE_FROM_PTR (use_p);
|
223 |
|
|
|
224 |
|
|
err = verify_ssa_name (ssa_name, is_virtual);
|
225 |
|
|
|
226 |
|
|
if (!TREE_VISITED (ssa_name))
|
227 |
|
|
if (verify_imm_links (stderr, ssa_name))
|
228 |
|
|
err = true;
|
229 |
|
|
|
230 |
|
|
TREE_VISITED (ssa_name) = 1;
|
231 |
|
|
|
232 |
|
|
if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name))
|
233 |
|
|
&& default_def (SSA_NAME_VAR (ssa_name)) == ssa_name)
|
234 |
|
|
; /* Default definitions have empty statements. Nothing to do. */
|
235 |
|
|
else if (!def_bb)
|
236 |
|
|
{
|
237 |
|
|
error ("missing definition");
|
238 |
|
|
err = true;
|
239 |
|
|
}
|
240 |
|
|
else if (bb != def_bb
|
241 |
|
|
&& !dominated_by_p (CDI_DOMINATORS, bb, def_bb))
|
242 |
|
|
{
|
243 |
|
|
error ("definition in block %i does not dominate use in block %i",
|
244 |
|
|
def_bb->index, bb->index);
|
245 |
|
|
err = true;
|
246 |
|
|
}
|
247 |
|
|
else if (bb == def_bb
|
248 |
|
|
&& names_defined_in_bb != NULL
|
249 |
|
|
&& !bitmap_bit_p (names_defined_in_bb, SSA_NAME_VERSION (ssa_name)))
|
250 |
|
|
{
|
251 |
|
|
error ("definition in block %i follows the use", def_bb->index);
|
252 |
|
|
err = true;
|
253 |
|
|
}
|
254 |
|
|
|
255 |
|
|
if (check_abnormal
|
256 |
|
|
&& !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ssa_name))
|
257 |
|
|
{
|
258 |
|
|
error ("SSA_NAME_OCCURS_IN_ABNORMAL_PHI should be set");
|
259 |
|
|
err = true;
|
260 |
|
|
}
|
261 |
|
|
|
262 |
|
|
/* Make sure the use is in an appropriate list by checking the previous
|
263 |
|
|
element to make sure it's the same. */
|
264 |
|
|
if (use_p->prev == NULL)
|
265 |
|
|
{
|
266 |
|
|
error ("no immediate_use list");
|
267 |
|
|
err = true;
|
268 |
|
|
}
|
269 |
|
|
else
|
270 |
|
|
{
|
271 |
|
|
tree listvar ;
|
272 |
|
|
if (use_p->prev->use == NULL)
|
273 |
|
|
listvar = use_p->prev->stmt;
|
274 |
|
|
else
|
275 |
|
|
listvar = USE_FROM_PTR (use_p->prev);
|
276 |
|
|
if (listvar != ssa_name)
|
277 |
|
|
{
|
278 |
|
|
error ("wrong immediate use list");
|
279 |
|
|
err = true;
|
280 |
|
|
}
|
281 |
|
|
}
|
282 |
|
|
|
283 |
|
|
if (err)
|
284 |
|
|
{
|
285 |
|
|
fprintf (stderr, "for SSA_NAME: ");
|
286 |
|
|
print_generic_expr (stderr, ssa_name, TDF_VOPS);
|
287 |
|
|
fprintf (stderr, " in statement:\n");
|
288 |
|
|
print_generic_stmt (stderr, stmt, TDF_VOPS);
|
289 |
|
|
}
|
290 |
|
|
|
291 |
|
|
return err;
|
292 |
|
|
}
|
293 |
|
|
|
294 |
|
|
|
295 |
|
|
/* Return true if any of the arguments for PHI node PHI at block BB is
|
296 |
|
|
malformed.
|
297 |
|
|
|
298 |
|
|
DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME version
|
299 |
|
|
numbers. If DEFINITION_BLOCK[SSA_NAME_VERSION] is set, it means that the
|
300 |
|
|
block in that array slot contains the definition of SSA_NAME. */
|
301 |
|
|
|
302 |
|
|
static bool
|
303 |
|
|
verify_phi_args (tree phi, basic_block bb, basic_block *definition_block)
|
304 |
|
|
{
|
305 |
|
|
edge e;
|
306 |
|
|
bool err = false;
|
307 |
|
|
unsigned i, phi_num_args = PHI_NUM_ARGS (phi);
|
308 |
|
|
|
309 |
|
|
if (EDGE_COUNT (bb->preds) != phi_num_args)
|
310 |
|
|
{
|
311 |
|
|
error ("incoming edge count does not match number of PHI arguments");
|
312 |
|
|
err = true;
|
313 |
|
|
goto error;
|
314 |
|
|
}
|
315 |
|
|
|
316 |
|
|
for (i = 0; i < phi_num_args; i++)
|
317 |
|
|
{
|
318 |
|
|
use_operand_p op_p = PHI_ARG_DEF_PTR (phi, i);
|
319 |
|
|
tree op = USE_FROM_PTR (op_p);
|
320 |
|
|
|
321 |
|
|
|
322 |
|
|
e = EDGE_PRED (bb, i);
|
323 |
|
|
|
324 |
|
|
if (op == NULL_TREE)
|
325 |
|
|
{
|
326 |
|
|
error ("PHI argument is missing for edge %d->%d",
|
327 |
|
|
e->src->index,
|
328 |
|
|
e->dest->index);
|
329 |
|
|
err = true;
|
330 |
|
|
goto error;
|
331 |
|
|
}
|
332 |
|
|
|
333 |
|
|
if (TREE_CODE (op) != SSA_NAME && !is_gimple_min_invariant (op))
|
334 |
|
|
{
|
335 |
|
|
error ("PHI argument is not SSA_NAME, or invariant");
|
336 |
|
|
err = true;
|
337 |
|
|
}
|
338 |
|
|
|
339 |
|
|
if (TREE_CODE (op) == SSA_NAME)
|
340 |
|
|
err = verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], op_p,
|
341 |
|
|
phi, e->flags & EDGE_ABNORMAL,
|
342 |
|
|
!is_gimple_reg (PHI_RESULT (phi)),
|
343 |
|
|
NULL);
|
344 |
|
|
|
345 |
|
|
if (e->dest != bb)
|
346 |
|
|
{
|
347 |
|
|
error ("wrong edge %d->%d for PHI argument",
|
348 |
|
|
e->src->index, e->dest->index);
|
349 |
|
|
err = true;
|
350 |
|
|
}
|
351 |
|
|
|
352 |
|
|
if (err)
|
353 |
|
|
{
|
354 |
|
|
fprintf (stderr, "PHI argument\n");
|
355 |
|
|
print_generic_stmt (stderr, op, TDF_VOPS);
|
356 |
|
|
goto error;
|
357 |
|
|
}
|
358 |
|
|
}
|
359 |
|
|
|
360 |
|
|
error:
|
361 |
|
|
if (err)
|
362 |
|
|
{
|
363 |
|
|
fprintf (stderr, "for PHI node\n");
|
364 |
|
|
print_generic_stmt (stderr, phi, TDF_VOPS);
|
365 |
|
|
}
|
366 |
|
|
|
367 |
|
|
|
368 |
|
|
return err;
|
369 |
|
|
}
|
370 |
|
|
|
371 |
|
|
|
372 |
|
|
static void
|
373 |
|
|
verify_flow_insensitive_alias_info (void)
|
374 |
|
|
{
|
375 |
|
|
tree var;
|
376 |
|
|
bitmap visited = BITMAP_ALLOC (NULL);
|
377 |
|
|
referenced_var_iterator rvi;
|
378 |
|
|
|
379 |
|
|
FOR_EACH_REFERENCED_VAR (var, rvi)
|
380 |
|
|
{
|
381 |
|
|
size_t j;
|
382 |
|
|
var_ann_t ann;
|
383 |
|
|
VEC(tree,gc) *may_aliases;
|
384 |
|
|
tree alias;
|
385 |
|
|
|
386 |
|
|
ann = var_ann (var);
|
387 |
|
|
may_aliases = ann->may_aliases;
|
388 |
|
|
|
389 |
|
|
for (j = 0; VEC_iterate (tree, may_aliases, j, alias); j++)
|
390 |
|
|
{
|
391 |
|
|
bitmap_set_bit (visited, DECL_UID (alias));
|
392 |
|
|
|
393 |
|
|
if (!may_be_aliased (alias))
|
394 |
|
|
{
|
395 |
|
|
error ("non-addressable variable inside an alias set");
|
396 |
|
|
debug_variable (alias);
|
397 |
|
|
goto err;
|
398 |
|
|
}
|
399 |
|
|
}
|
400 |
|
|
}
|
401 |
|
|
|
402 |
|
|
FOR_EACH_REFERENCED_VAR (var, rvi)
|
403 |
|
|
{
|
404 |
|
|
var_ann_t ann;
|
405 |
|
|
ann = var_ann (var);
|
406 |
|
|
|
407 |
|
|
if (!MTAG_P (var)
|
408 |
|
|
&& ann->is_aliased
|
409 |
|
|
&& !bitmap_bit_p (visited, DECL_UID (var)))
|
410 |
|
|
{
|
411 |
|
|
error ("addressable variable that is aliased but is not in any alias set");
|
412 |
|
|
goto err;
|
413 |
|
|
}
|
414 |
|
|
}
|
415 |
|
|
|
416 |
|
|
BITMAP_FREE (visited);
|
417 |
|
|
return;
|
418 |
|
|
|
419 |
|
|
err:
|
420 |
|
|
debug_variable (var);
|
421 |
|
|
internal_error ("verify_flow_insensitive_alias_info failed");
|
422 |
|
|
}
|
423 |
|
|
|
424 |
|
|
|
425 |
|
|
static void
|
426 |
|
|
verify_flow_sensitive_alias_info (void)
|
427 |
|
|
{
|
428 |
|
|
size_t i;
|
429 |
|
|
tree ptr;
|
430 |
|
|
|
431 |
|
|
for (i = 1; i < num_ssa_names; i++)
|
432 |
|
|
{
|
433 |
|
|
tree var;
|
434 |
|
|
var_ann_t ann;
|
435 |
|
|
struct ptr_info_def *pi;
|
436 |
|
|
|
437 |
|
|
|
438 |
|
|
ptr = ssa_name (i);
|
439 |
|
|
if (!ptr)
|
440 |
|
|
continue;
|
441 |
|
|
|
442 |
|
|
/* We only care for pointers that are actually referenced in the
|
443 |
|
|
program. */
|
444 |
|
|
if (!POINTER_TYPE_P (TREE_TYPE (ptr)) || !TREE_VISITED (ptr))
|
445 |
|
|
continue;
|
446 |
|
|
|
447 |
|
|
/* RESULT_DECL is special. If it's a GIMPLE register, then it
|
448 |
|
|
is only written-to only once in the return statement.
|
449 |
|
|
Otherwise, aggregate RESULT_DECLs may be written-to more than
|
450 |
|
|
once in virtual operands. */
|
451 |
|
|
var = SSA_NAME_VAR (ptr);
|
452 |
|
|
if (TREE_CODE (var) == RESULT_DECL
|
453 |
|
|
&& is_gimple_reg (ptr))
|
454 |
|
|
continue;
|
455 |
|
|
|
456 |
|
|
pi = SSA_NAME_PTR_INFO (ptr);
|
457 |
|
|
if (pi == NULL)
|
458 |
|
|
continue;
|
459 |
|
|
|
460 |
|
|
ann = var_ann (var);
|
461 |
|
|
if (pi->is_dereferenced && !pi->name_mem_tag && !ann->symbol_mem_tag)
|
462 |
|
|
{
|
463 |
|
|
error ("dereferenced pointers should have a name or a symbol tag");
|
464 |
|
|
goto err;
|
465 |
|
|
}
|
466 |
|
|
|
467 |
|
|
if (pi->name_mem_tag
|
468 |
|
|
&& (pi->pt_vars == NULL || bitmap_empty_p (pi->pt_vars)))
|
469 |
|
|
{
|
470 |
|
|
error ("pointers with a memory tag, should have points-to sets");
|
471 |
|
|
goto err;
|
472 |
|
|
}
|
473 |
|
|
|
474 |
|
|
if (pi->value_escapes_p
|
475 |
|
|
&& pi->name_mem_tag
|
476 |
|
|
&& !is_call_clobbered (pi->name_mem_tag))
|
477 |
|
|
{
|
478 |
|
|
error ("pointer escapes but its name tag is not call-clobbered");
|
479 |
|
|
goto err;
|
480 |
|
|
}
|
481 |
|
|
}
|
482 |
|
|
|
483 |
|
|
return;
|
484 |
|
|
|
485 |
|
|
err:
|
486 |
|
|
debug_variable (ptr);
|
487 |
|
|
internal_error ("verify_flow_sensitive_alias_info failed");
|
488 |
|
|
}
|
489 |
|
|
|
490 |
|
|
DEF_VEC_P (bitmap);
|
491 |
|
|
DEF_VEC_ALLOC_P (bitmap,heap);
|
492 |
|
|
|
493 |
|
|
/* Verify that all name tags have different points to sets.
|
494 |
|
|
This algorithm takes advantage of the fact that every variable with the
|
495 |
|
|
same name tag must have the same points-to set.
|
496 |
|
|
So we check a single variable for each name tag, and verify that its
|
497 |
|
|
points-to set is different from every other points-to set for other name
|
498 |
|
|
tags.
|
499 |
|
|
|
500 |
|
|
Additionally, given a pointer P_i with name tag NMT and symbol tag
|
501 |
|
|
SMT, this function verified the alias set of SMT is a superset of
|
502 |
|
|
the alias set of NMT. */
|
503 |
|
|
|
504 |
|
|
static void
|
505 |
|
|
verify_name_tags (void)
|
506 |
|
|
{
|
507 |
|
|
size_t i;
|
508 |
|
|
size_t j;
|
509 |
|
|
bitmap first, second;
|
510 |
|
|
VEC(tree,heap) *name_tag_reps = NULL;
|
511 |
|
|
VEC(bitmap,heap) *pt_vars_for_reps = NULL;
|
512 |
|
|
bitmap type_aliases = BITMAP_ALLOC (NULL);
|
513 |
|
|
|
514 |
|
|
/* First we compute the name tag representatives and their points-to sets. */
|
515 |
|
|
for (i = 0; i < num_ssa_names; i++)
|
516 |
|
|
{
|
517 |
|
|
struct ptr_info_def *pi;
|
518 |
|
|
tree smt, ptr = ssa_name (i);
|
519 |
|
|
|
520 |
|
|
if (ptr == NULL_TREE)
|
521 |
|
|
continue;
|
522 |
|
|
|
523 |
|
|
pi = SSA_NAME_PTR_INFO (ptr);
|
524 |
|
|
|
525 |
|
|
if (!TREE_VISITED (ptr)
|
526 |
|
|
|| !POINTER_TYPE_P (TREE_TYPE (ptr))
|
527 |
|
|
|| !pi
|
528 |
|
|
|| !pi->name_mem_tag
|
529 |
|
|
|| TREE_VISITED (pi->name_mem_tag))
|
530 |
|
|
continue;
|
531 |
|
|
|
532 |
|
|
TREE_VISITED (pi->name_mem_tag) = 1;
|
533 |
|
|
|
534 |
|
|
if (pi->pt_vars == NULL)
|
535 |
|
|
continue;
|
536 |
|
|
|
537 |
|
|
VEC_safe_push (tree, heap, name_tag_reps, ptr);
|
538 |
|
|
VEC_safe_push (bitmap, heap, pt_vars_for_reps, pi->pt_vars);
|
539 |
|
|
|
540 |
|
|
/* Verify that alias set of PTR's symbol tag is a superset of the
|
541 |
|
|
alias set of PTR's name tag. */
|
542 |
|
|
smt = var_ann (SSA_NAME_VAR (ptr))->symbol_mem_tag;
|
543 |
|
|
if (smt)
|
544 |
|
|
{
|
545 |
|
|
size_t i;
|
546 |
|
|
VEC(tree,gc) *aliases = var_ann (smt)->may_aliases;
|
547 |
|
|
tree alias;
|
548 |
|
|
|
549 |
|
|
bitmap_clear (type_aliases);
|
550 |
|
|
for (i = 0; VEC_iterate (tree, aliases, i, alias); i++)
|
551 |
|
|
bitmap_set_bit (type_aliases, DECL_UID (alias));
|
552 |
|
|
|
553 |
|
|
/* When grouping, we may have added PTR's symbol tag into the
|
554 |
|
|
alias set of PTR's name tag. To prevent a false
|
555 |
|
|
positive, pretend that SMT is in its own alias set. */
|
556 |
|
|
bitmap_set_bit (type_aliases, DECL_UID (smt));
|
557 |
|
|
|
558 |
|
|
if (bitmap_equal_p (type_aliases, pi->pt_vars))
|
559 |
|
|
continue;
|
560 |
|
|
|
561 |
|
|
if (!bitmap_intersect_compl_p (type_aliases, pi->pt_vars))
|
562 |
|
|
{
|
563 |
|
|
error ("alias set of a pointer's symbol tag should be a superset of the corresponding name tag");
|
564 |
|
|
debug_variable (smt);
|
565 |
|
|
debug_variable (pi->name_mem_tag);
|
566 |
|
|
goto err;
|
567 |
|
|
}
|
568 |
|
|
}
|
569 |
|
|
}
|
570 |
|
|
|
571 |
|
|
/* Now compare all the representative bitmaps with all other representative
|
572 |
|
|
bitmaps, to verify that they are all different. */
|
573 |
|
|
for (i = 0; VEC_iterate (bitmap, pt_vars_for_reps, i, first); i++)
|
574 |
|
|
{
|
575 |
|
|
for (j = i + 1; VEC_iterate (bitmap, pt_vars_for_reps, j, second); j++)
|
576 |
|
|
{
|
577 |
|
|
if (bitmap_equal_p (first, second))
|
578 |
|
|
{
|
579 |
|
|
error ("two different pointers with identical points-to sets but different name tags");
|
580 |
|
|
debug_variable (VEC_index (tree, name_tag_reps, j));
|
581 |
|
|
goto err;
|
582 |
|
|
}
|
583 |
|
|
}
|
584 |
|
|
}
|
585 |
|
|
|
586 |
|
|
/* Lastly, clear out the visited flags. */
|
587 |
|
|
for (i = 0; i < num_ssa_names; i++)
|
588 |
|
|
{
|
589 |
|
|
if (ssa_name (i))
|
590 |
|
|
{
|
591 |
|
|
tree ptr = ssa_name (i);
|
592 |
|
|
struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);
|
593 |
|
|
if (!TREE_VISITED (ptr)
|
594 |
|
|
|| !POINTER_TYPE_P (TREE_TYPE (ptr))
|
595 |
|
|
|| !pi
|
596 |
|
|
|| !pi->name_mem_tag)
|
597 |
|
|
continue;
|
598 |
|
|
TREE_VISITED (pi->name_mem_tag) = 0;
|
599 |
|
|
}
|
600 |
|
|
}
|
601 |
|
|
|
602 |
|
|
/* We do not have to free the bitmaps or trees in the vectors, as
|
603 |
|
|
they are not owned by us. */
|
604 |
|
|
VEC_free (bitmap, heap, pt_vars_for_reps);
|
605 |
|
|
VEC_free (tree, heap, name_tag_reps);
|
606 |
|
|
BITMAP_FREE (type_aliases);
|
607 |
|
|
return;
|
608 |
|
|
|
609 |
|
|
err:
|
610 |
|
|
debug_variable (VEC_index (tree, name_tag_reps, i));
|
611 |
|
|
internal_error ("verify_name_tags failed");
|
612 |
|
|
}
|
613 |
|
|
|
614 |
|
|
|
615 |
|
|
/* Verify the consistency of call clobbering information. */
|
616 |
|
|
static void
|
617 |
|
|
verify_call_clobbering (void)
|
618 |
|
|
{
|
619 |
|
|
unsigned int i;
|
620 |
|
|
bitmap_iterator bi;
|
621 |
|
|
tree var;
|
622 |
|
|
referenced_var_iterator rvi;
|
623 |
|
|
|
624 |
|
|
/* At all times, the result of the DECL_CALL_CLOBBERED flag should
|
625 |
|
|
match the result of the call_clobbered_vars bitmap. Verify both
|
626 |
|
|
that everything in call_clobbered_vars is marked
|
627 |
|
|
DECL_CALL_CLOBBERED, and that everything marked
|
628 |
|
|
DECL_CALL_CLOBBERED is in call_clobbered_vars. */
|
629 |
|
|
EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, bi)
|
630 |
|
|
{
|
631 |
|
|
var = referenced_var (i);
|
632 |
|
|
if (!MTAG_P (var) && !DECL_CALL_CLOBBERED (var))
|
633 |
|
|
{
|
634 |
|
|
error ("variable in call_clobbered_vars but not marked DECL_CALL_CLOBBERED");
|
635 |
|
|
debug_variable (var);
|
636 |
|
|
goto err;
|
637 |
|
|
}
|
638 |
|
|
}
|
639 |
|
|
FOR_EACH_REFERENCED_VAR (var, rvi)
|
640 |
|
|
{
|
641 |
|
|
if (!MTAG_P (var) && DECL_CALL_CLOBBERED (var)
|
642 |
|
|
&& !bitmap_bit_p (call_clobbered_vars, DECL_UID (var)))
|
643 |
|
|
{
|
644 |
|
|
error ("variable marked DECL_CALL_CLOBBERED but not in call_clobbered_vars bitmap.");
|
645 |
|
|
debug_variable (var);
|
646 |
|
|
goto err;
|
647 |
|
|
}
|
648 |
|
|
}
|
649 |
|
|
return;
|
650 |
|
|
|
651 |
|
|
err:
|
652 |
|
|
internal_error ("verify_call_clobbering failed");
|
653 |
|
|
}
|
654 |
|
|
|
655 |
|
|
/* Verify the consistency of aliasing information. */
|
656 |
|
|
|
657 |
|
|
static void
|
658 |
|
|
verify_alias_info (void)
|
659 |
|
|
{
|
660 |
|
|
verify_flow_sensitive_alias_info ();
|
661 |
|
|
verify_name_tags ();
|
662 |
|
|
verify_call_clobbering ();
|
663 |
|
|
verify_flow_insensitive_alias_info ();
|
664 |
|
|
}
|
665 |
|
|
|
666 |
|
|
|
667 |
|
|
/* Verify common invariants in the SSA web.
|
668 |
|
|
TODO: verify the variable annotations. */
|
669 |
|
|
|
670 |
|
|
void
|
671 |
|
|
verify_ssa (bool check_modified_stmt)
|
672 |
|
|
{
|
673 |
|
|
size_t i;
|
674 |
|
|
basic_block bb;
|
675 |
|
|
basic_block *definition_block = XCNEWVEC (basic_block, num_ssa_names);
|
676 |
|
|
ssa_op_iter iter;
|
677 |
|
|
tree op;
|
678 |
|
|
enum dom_state orig_dom_state = dom_computed[CDI_DOMINATORS];
|
679 |
|
|
bitmap names_defined_in_bb = BITMAP_ALLOC (NULL);
|
680 |
|
|
|
681 |
|
|
gcc_assert (!need_ssa_update_p ());
|
682 |
|
|
|
683 |
|
|
verify_stmts ();
|
684 |
|
|
|
685 |
|
|
timevar_push (TV_TREE_SSA_VERIFY);
|
686 |
|
|
|
687 |
|
|
/* Keep track of SSA names present in the IL. */
|
688 |
|
|
for (i = 1; i < num_ssa_names; i++)
|
689 |
|
|
{
|
690 |
|
|
tree name = ssa_name (i);
|
691 |
|
|
if (name)
|
692 |
|
|
{
|
693 |
|
|
tree stmt;
|
694 |
|
|
TREE_VISITED (name) = 0;
|
695 |
|
|
|
696 |
|
|
stmt = SSA_NAME_DEF_STMT (name);
|
697 |
|
|
if (!IS_EMPTY_STMT (stmt))
|
698 |
|
|
{
|
699 |
|
|
basic_block bb = bb_for_stmt (stmt);
|
700 |
|
|
verify_def (bb, definition_block,
|
701 |
|
|
name, stmt, !is_gimple_reg (name));
|
702 |
|
|
|
703 |
|
|
}
|
704 |
|
|
}
|
705 |
|
|
}
|
706 |
|
|
|
707 |
|
|
calculate_dominance_info (CDI_DOMINATORS);
|
708 |
|
|
|
709 |
|
|
/* Now verify all the uses and make sure they agree with the definitions
|
710 |
|
|
found in the previous pass. */
|
711 |
|
|
FOR_EACH_BB (bb)
|
712 |
|
|
{
|
713 |
|
|
edge e;
|
714 |
|
|
tree phi;
|
715 |
|
|
edge_iterator ei;
|
716 |
|
|
block_stmt_iterator bsi;
|
717 |
|
|
|
718 |
|
|
/* Make sure that all edges have a clear 'aux' field. */
|
719 |
|
|
FOR_EACH_EDGE (e, ei, bb->preds)
|
720 |
|
|
{
|
721 |
|
|
if (e->aux)
|
722 |
|
|
{
|
723 |
|
|
error ("AUX pointer initialized for edge %d->%d", e->src->index,
|
724 |
|
|
e->dest->index);
|
725 |
|
|
goto err;
|
726 |
|
|
}
|
727 |
|
|
}
|
728 |
|
|
|
729 |
|
|
/* Verify the arguments for every PHI node in the block. */
|
730 |
|
|
for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
|
731 |
|
|
{
|
732 |
|
|
if (verify_phi_args (phi, bb, definition_block))
|
733 |
|
|
goto err;
|
734 |
|
|
bitmap_set_bit (names_defined_in_bb,
|
735 |
|
|
SSA_NAME_VERSION (PHI_RESULT (phi)));
|
736 |
|
|
}
|
737 |
|
|
|
738 |
|
|
/* Now verify all the uses and vuses in every statement of the block. */
|
739 |
|
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
740 |
|
|
{
|
741 |
|
|
tree stmt = bsi_stmt (bsi);
|
742 |
|
|
use_operand_p use_p;
|
743 |
|
|
|
744 |
|
|
if (check_modified_stmt && stmt_modified_p (stmt))
|
745 |
|
|
{
|
746 |
|
|
error ("stmt (%p) marked modified after optimization pass : ",
|
747 |
|
|
(void *)stmt);
|
748 |
|
|
print_generic_stmt (stderr, stmt, TDF_VOPS);
|
749 |
|
|
goto err;
|
750 |
|
|
}
|
751 |
|
|
|
752 |
|
|
if (TREE_CODE (stmt) == MODIFY_EXPR
|
753 |
|
|
&& TREE_CODE (TREE_OPERAND (stmt, 0)) != SSA_NAME)
|
754 |
|
|
{
|
755 |
|
|
tree lhs, base_address;
|
756 |
|
|
|
757 |
|
|
lhs = TREE_OPERAND (stmt, 0);
|
758 |
|
|
base_address = get_base_address (lhs);
|
759 |
|
|
|
760 |
|
|
if (base_address
|
761 |
|
|
&& SSA_VAR_P (base_address)
|
762 |
|
|
&& ZERO_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF|SSA_OP_VMUSTDEF))
|
763 |
|
|
{
|
764 |
|
|
error ("statement makes a memory store, but has no "
|
765 |
|
|
"V_MAY_DEFS nor V_MUST_DEFS");
|
766 |
|
|
print_generic_stmt (stderr, stmt, TDF_VOPS);
|
767 |
|
|
goto err;
|
768 |
|
|
}
|
769 |
|
|
}
|
770 |
|
|
|
771 |
|
|
FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
|
772 |
|
|
SSA_OP_ALL_USES | SSA_OP_ALL_KILLS)
|
773 |
|
|
{
|
774 |
|
|
op = USE_FROM_PTR (use_p);
|
775 |
|
|
if (verify_use (bb, definition_block[SSA_NAME_VERSION (op)],
|
776 |
|
|
use_p, stmt, false, !is_gimple_reg (op),
|
777 |
|
|
names_defined_in_bb))
|
778 |
|
|
goto err;
|
779 |
|
|
}
|
780 |
|
|
|
781 |
|
|
FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_DEFS)
|
782 |
|
|
bitmap_set_bit (names_defined_in_bb, SSA_NAME_VERSION (op));
|
783 |
|
|
}
|
784 |
|
|
|
785 |
|
|
bitmap_clear (names_defined_in_bb);
|
786 |
|
|
}
|
787 |
|
|
|
788 |
|
|
/* Finally, verify alias information. */
|
789 |
|
|
verify_alias_info ();
|
790 |
|
|
|
791 |
|
|
free (definition_block);
|
792 |
|
|
|
793 |
|
|
/* Restore the dominance information to its prior known state, so
|
794 |
|
|
that we do not perturb the compiler's subsequent behavior. */
|
795 |
|
|
if (orig_dom_state == DOM_NONE)
|
796 |
|
|
free_dominance_info (CDI_DOMINATORS);
|
797 |
|
|
else
|
798 |
|
|
dom_computed[CDI_DOMINATORS] = orig_dom_state;
|
799 |
|
|
|
800 |
|
|
BITMAP_FREE (names_defined_in_bb);
|
801 |
|
|
timevar_pop (TV_TREE_SSA_VERIFY);
|
802 |
|
|
return;
|
803 |
|
|
|
804 |
|
|
err:
|
805 |
|
|
internal_error ("verify_ssa failed");
|
806 |
|
|
}
|
807 |
|
|
|
808 |
|
|
/* Return true if the uid in both int tree maps are equal. */
|
809 |
|
|
|
810 |
|
|
int
|
811 |
|
|
int_tree_map_eq (const void *va, const void *vb)
|
812 |
|
|
{
|
813 |
|
|
const struct int_tree_map *a = (const struct int_tree_map *) va;
|
814 |
|
|
const struct int_tree_map *b = (const struct int_tree_map *) vb;
|
815 |
|
|
return (a->uid == b->uid);
|
816 |
|
|
}
|
817 |
|
|
|
818 |
|
|
/* Hash a UID in a int_tree_map. */
|
819 |
|
|
|
820 |
|
|
unsigned int
|
821 |
|
|
int_tree_map_hash (const void *item)
|
822 |
|
|
{
|
823 |
|
|
return ((const struct int_tree_map *)item)->uid;
|
824 |
|
|
}
|
825 |
|
|
|
826 |
|
|
|
827 |
|
|
/* Initialize global DFA and SSA structures. */
|
828 |
|
|
|
829 |
|
|
void
|
830 |
|
|
init_tree_ssa (void)
|
831 |
|
|
{
|
832 |
|
|
referenced_vars = htab_create_ggc (20, int_tree_map_hash,
|
833 |
|
|
int_tree_map_eq, NULL);
|
834 |
|
|
default_defs = htab_create_ggc (20, int_tree_map_hash, int_tree_map_eq, NULL);
|
835 |
|
|
call_clobbered_vars = BITMAP_ALLOC (NULL);
|
836 |
|
|
addressable_vars = BITMAP_ALLOC (NULL);
|
837 |
|
|
init_alias_heapvars ();
|
838 |
|
|
init_ssanames ();
|
839 |
|
|
init_phinodes ();
|
840 |
|
|
global_var = NULL_TREE;
|
841 |
|
|
aliases_computed_p = false;
|
842 |
|
|
}
|
843 |
|
|
|
844 |
|
|
|
845 |
|
|
/* Deallocate memory associated with SSA data structures for FNDECL. */
|
846 |
|
|
|
847 |
|
|
void
|
848 |
|
|
delete_tree_ssa (void)
|
849 |
|
|
{
|
850 |
|
|
size_t i;
|
851 |
|
|
basic_block bb;
|
852 |
|
|
block_stmt_iterator bsi;
|
853 |
|
|
referenced_var_iterator rvi;
|
854 |
|
|
tree var;
|
855 |
|
|
|
856 |
|
|
/* Release any ssa_names still in use. */
|
857 |
|
|
for (i = 0; i < num_ssa_names; i++)
|
858 |
|
|
{
|
859 |
|
|
tree var = ssa_name (i);
|
860 |
|
|
if (var && TREE_CODE (var) == SSA_NAME)
|
861 |
|
|
{
|
862 |
|
|
SSA_NAME_IMM_USE_NODE (var).prev = &(SSA_NAME_IMM_USE_NODE (var));
|
863 |
|
|
SSA_NAME_IMM_USE_NODE (var).next = &(SSA_NAME_IMM_USE_NODE (var));
|
864 |
|
|
}
|
865 |
|
|
release_ssa_name (var);
|
866 |
|
|
}
|
867 |
|
|
|
868 |
|
|
/* Remove annotations from every tree in the function. */
|
869 |
|
|
FOR_EACH_BB (bb)
|
870 |
|
|
{
|
871 |
|
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
872 |
|
|
{
|
873 |
|
|
tree stmt = bsi_stmt (bsi);
|
874 |
|
|
stmt_ann_t ann = get_stmt_ann (stmt);
|
875 |
|
|
|
876 |
|
|
free_ssa_operands (&ann->operands);
|
877 |
|
|
ann->addresses_taken = 0;
|
878 |
|
|
mark_stmt_modified (stmt);
|
879 |
|
|
}
|
880 |
|
|
set_phi_nodes (bb, NULL);
|
881 |
|
|
}
|
882 |
|
|
|
883 |
|
|
/* Remove annotations from every referenced variable. */
|
884 |
|
|
FOR_EACH_REFERENCED_VAR (var, rvi)
|
885 |
|
|
{
|
886 |
|
|
ggc_free (var->common.ann);
|
887 |
|
|
var->common.ann = NULL;
|
888 |
|
|
}
|
889 |
|
|
htab_delete (referenced_vars);
|
890 |
|
|
referenced_vars = NULL;
|
891 |
|
|
|
892 |
|
|
fini_ssanames ();
|
893 |
|
|
fini_phinodes ();
|
894 |
|
|
|
895 |
|
|
global_var = NULL_TREE;
|
896 |
|
|
|
897 |
|
|
htab_delete (default_defs);
|
898 |
|
|
BITMAP_FREE (call_clobbered_vars);
|
899 |
|
|
call_clobbered_vars = NULL;
|
900 |
|
|
BITMAP_FREE (addressable_vars);
|
901 |
|
|
addressable_vars = NULL;
|
902 |
|
|
modified_noreturn_calls = NULL;
|
903 |
|
|
aliases_computed_p = false;
|
904 |
|
|
delete_alias_heapvars ();
|
905 |
|
|
gcc_assert (!need_ssa_update_p ());
|
906 |
|
|
}
|
907 |
|
|
|
908 |
|
|
|
909 |
|
|
/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a
|
910 |
|
|
useless type conversion, otherwise return false. */
|
911 |
|
|
|
912 |
|
|
bool
|
913 |
|
|
tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type)
|
914 |
|
|
{
|
915 |
|
|
if (inner_type == outer_type)
|
916 |
|
|
return true;
|
917 |
|
|
|
918 |
|
|
/* Changes in machine mode are never useless conversions. */
|
919 |
|
|
if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type))
|
920 |
|
|
return false;
|
921 |
|
|
|
922 |
|
|
/* If the inner and outer types are effectively the same, then
|
923 |
|
|
strip the type conversion and enter the equivalence into
|
924 |
|
|
the table. */
|
925 |
|
|
if (lang_hooks.types_compatible_p (inner_type, outer_type))
|
926 |
|
|
return true;
|
927 |
|
|
|
928 |
|
|
/* If both types are pointers and the outer type is a (void *), then
|
929 |
|
|
the conversion is not necessary. The opposite is not true since
|
930 |
|
|
that conversion would result in a loss of information if the
|
931 |
|
|
equivalence was used. Consider an indirect function call where
|
932 |
|
|
we need to know the exact type of the function to correctly
|
933 |
|
|
implement the ABI. */
|
934 |
|
|
else if (POINTER_TYPE_P (inner_type)
|
935 |
|
|
&& POINTER_TYPE_P (outer_type)
|
936 |
|
|
&& TYPE_REF_CAN_ALIAS_ALL (inner_type)
|
937 |
|
|
== TYPE_REF_CAN_ALIAS_ALL (outer_type)
|
938 |
|
|
&& TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE)
|
939 |
|
|
return true;
|
940 |
|
|
|
941 |
|
|
/* Don't lose casts between pointers to volatile and non-volatile
|
942 |
|
|
qualified types. Doing so would result in changing the semantics
|
943 |
|
|
of later accesses. */
|
944 |
|
|
else if (POINTER_TYPE_P (inner_type)
|
945 |
|
|
&& POINTER_TYPE_P (outer_type)
|
946 |
|
|
&& TYPE_VOLATILE (TREE_TYPE (outer_type))
|
947 |
|
|
!= TYPE_VOLATILE (TREE_TYPE (inner_type)))
|
948 |
|
|
return false;
|
949 |
|
|
|
950 |
|
|
/* Pointers/references are equivalent if their pointed to types
|
951 |
|
|
are effectively the same. This allows to strip conversions between
|
952 |
|
|
pointer types with different type qualifiers. */
|
953 |
|
|
else if (POINTER_TYPE_P (inner_type)
|
954 |
|
|
&& POINTER_TYPE_P (outer_type)
|
955 |
|
|
&& TYPE_REF_CAN_ALIAS_ALL (inner_type)
|
956 |
|
|
== TYPE_REF_CAN_ALIAS_ALL (outer_type)
|
957 |
|
|
&& lang_hooks.types_compatible_p (TREE_TYPE (inner_type),
|
958 |
|
|
TREE_TYPE (outer_type)))
|
959 |
|
|
return true;
|
960 |
|
|
|
961 |
|
|
/* If both the inner and outer types are integral types, then the
|
962 |
|
|
conversion is not necessary if they have the same mode and
|
963 |
|
|
signedness and precision, and both or neither are boolean. Some
|
964 |
|
|
code assumes an invariant that boolean types stay boolean and do
|
965 |
|
|
not become 1-bit bit-field types. Note that types with precision
|
966 |
|
|
not using all bits of the mode (such as bit-field types in C)
|
967 |
|
|
mean that testing of precision is necessary. */
|
968 |
|
|
else if (INTEGRAL_TYPE_P (inner_type)
|
969 |
|
|
&& INTEGRAL_TYPE_P (outer_type)
|
970 |
|
|
&& TYPE_UNSIGNED (inner_type) == TYPE_UNSIGNED (outer_type)
|
971 |
|
|
&& TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type)
|
972 |
|
|
&& simple_cst_equal (TYPE_MAX_VALUE (inner_type), TYPE_MAX_VALUE (outer_type))
|
973 |
|
|
&& simple_cst_equal (TYPE_MIN_VALUE (inner_type), TYPE_MIN_VALUE (outer_type)))
|
974 |
|
|
{
|
975 |
|
|
bool first_boolean = (TREE_CODE (inner_type) == BOOLEAN_TYPE);
|
976 |
|
|
bool second_boolean = (TREE_CODE (outer_type) == BOOLEAN_TYPE);
|
977 |
|
|
if (first_boolean == second_boolean)
|
978 |
|
|
return true;
|
979 |
|
|
}
|
980 |
|
|
|
981 |
|
|
/* Recurse for complex types. */
|
982 |
|
|
else if (TREE_CODE (inner_type) == COMPLEX_TYPE
|
983 |
|
|
&& TREE_CODE (outer_type) == COMPLEX_TYPE
|
984 |
|
|
&& tree_ssa_useless_type_conversion_1 (TREE_TYPE (outer_type),
|
985 |
|
|
TREE_TYPE (inner_type)))
|
986 |
|
|
return true;
|
987 |
|
|
|
988 |
|
|
return false;
|
989 |
|
|
}
|
990 |
|
|
|
991 |
|
|
/* Return true if EXPR is a useless type conversion, otherwise return
|
992 |
|
|
false. */
|
993 |
|
|
|
994 |
|
|
bool
|
995 |
|
|
tree_ssa_useless_type_conversion (tree expr)
|
996 |
|
|
{
|
997 |
|
|
/* If we have an assignment that merely uses a NOP_EXPR to change
|
998 |
|
|
the top of the RHS to the type of the LHS and the type conversion
|
999 |
|
|
is "safe", then strip away the type conversion so that we can
|
1000 |
|
|
enter LHS = RHS into the const_and_copies table. */
|
1001 |
|
|
if (TREE_CODE (expr) == NOP_EXPR || TREE_CODE (expr) == CONVERT_EXPR
|
1002 |
|
|
|| TREE_CODE (expr) == VIEW_CONVERT_EXPR
|
1003 |
|
|
|| TREE_CODE (expr) == NON_LVALUE_EXPR)
|
1004 |
|
|
return tree_ssa_useless_type_conversion_1 (TREE_TYPE (expr),
|
1005 |
|
|
TREE_TYPE (TREE_OPERAND (expr,
|
1006 |
|
|
0)));
|
1007 |
|
|
|
1008 |
|
|
|
1009 |
|
|
return false;
|
1010 |
|
|
}
|
1011 |
|
|
|
1012 |
|
|
/* Returns true if statement STMT may read memory. */
|
1013 |
|
|
|
1014 |
|
|
bool
|
1015 |
|
|
stmt_references_memory_p (tree stmt)
|
1016 |
|
|
{
|
1017 |
|
|
stmt_ann_t ann = stmt_ann (stmt);
|
1018 |
|
|
|
1019 |
|
|
if (ann->has_volatile_ops)
|
1020 |
|
|
return true;
|
1021 |
|
|
|
1022 |
|
|
return (!ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS));
|
1023 |
|
|
}
|
1024 |
|
|
|
1025 |
|
|
/* Internal helper for walk_use_def_chains. VAR, FN and DATA are as
|
1026 |
|
|
described in walk_use_def_chains.
|
1027 |
|
|
|
1028 |
|
|
VISITED is a pointer set used to mark visited SSA_NAMEs to avoid
|
1029 |
|
|
infinite loops. We used to have a bitmap for this to just mark
|
1030 |
|
|
SSA versions we had visited. But non-sparse bitmaps are way too
|
1031 |
|
|
expensive, while sparse bitmaps may cause quadratic behavior.
|
1032 |
|
|
|
1033 |
|
|
IS_DFS is true if the caller wants to perform a depth-first search
|
1034 |
|
|
when visiting PHI nodes. A DFS will visit each PHI argument and
|
1035 |
|
|
call FN after each one. Otherwise, all the arguments are
|
1036 |
|
|
visited first and then FN is called with each of the visited
|
1037 |
|
|
arguments in a separate pass. */
|
1038 |
|
|
|
1039 |
|
|
static bool
|
1040 |
|
|
walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data,
|
1041 |
|
|
struct pointer_set_t *visited, bool is_dfs)
|
1042 |
|
|
{
|
1043 |
|
|
tree def_stmt;
|
1044 |
|
|
|
1045 |
|
|
if (pointer_set_insert (visited, var))
|
1046 |
|
|
return false;
|
1047 |
|
|
|
1048 |
|
|
def_stmt = SSA_NAME_DEF_STMT (var);
|
1049 |
|
|
|
1050 |
|
|
if (TREE_CODE (def_stmt) != PHI_NODE)
|
1051 |
|
|
{
|
1052 |
|
|
/* If we reached the end of the use-def chain, call FN. */
|
1053 |
|
|
return fn (var, def_stmt, data);
|
1054 |
|
|
}
|
1055 |
|
|
else
|
1056 |
|
|
{
|
1057 |
|
|
int i;
|
1058 |
|
|
|
1059 |
|
|
/* When doing a breadth-first search, call FN before following the
|
1060 |
|
|
use-def links for each argument. */
|
1061 |
|
|
if (!is_dfs)
|
1062 |
|
|
for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
|
1063 |
|
|
if (fn (PHI_ARG_DEF (def_stmt, i), def_stmt, data))
|
1064 |
|
|
return true;
|
1065 |
|
|
|
1066 |
|
|
/* Follow use-def links out of each PHI argument. */
|
1067 |
|
|
for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
|
1068 |
|
|
{
|
1069 |
|
|
tree arg = PHI_ARG_DEF (def_stmt, i);
|
1070 |
|
|
if (TREE_CODE (arg) == SSA_NAME
|
1071 |
|
|
&& walk_use_def_chains_1 (arg, fn, data, visited, is_dfs))
|
1072 |
|
|
return true;
|
1073 |
|
|
}
|
1074 |
|
|
|
1075 |
|
|
/* When doing a depth-first search, call FN after following the
|
1076 |
|
|
use-def links for each argument. */
|
1077 |
|
|
if (is_dfs)
|
1078 |
|
|
for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
|
1079 |
|
|
if (fn (PHI_ARG_DEF (def_stmt, i), def_stmt, data))
|
1080 |
|
|
return true;
|
1081 |
|
|
}
|
1082 |
|
|
|
1083 |
|
|
return false;
|
1084 |
|
|
}
|
1085 |
|
|
|
1086 |
|
|
|
1087 |
|
|
|
1088 |
|
|
/* Walk use-def chains starting at the SSA variable VAR. Call
|
1089 |
|
|
function FN at each reaching definition found. FN takes three
|
1090 |
|
|
arguments: VAR, its defining statement (DEF_STMT) and a generic
|
1091 |
|
|
pointer to whatever state information that FN may want to maintain
|
1092 |
|
|
(DATA). FN is able to stop the walk by returning true, otherwise
|
1093 |
|
|
in order to continue the walk, FN should return false.
|
1094 |
|
|
|
1095 |
|
|
Note, that if DEF_STMT is a PHI node, the semantics are slightly
|
1096 |
|
|
different. The first argument to FN is no longer the original
|
1097 |
|
|
variable VAR, but the PHI argument currently being examined. If FN
|
1098 |
|
|
wants to get at VAR, it should call PHI_RESULT (PHI).
|
1099 |
|
|
|
1100 |
|
|
If IS_DFS is true, this function will:
|
1101 |
|
|
|
1102 |
|
|
1- walk the use-def chains for all the PHI arguments, and,
|
1103 |
|
|
2- call (*FN) (ARG, PHI, DATA) on all the PHI arguments.
|
1104 |
|
|
|
1105 |
|
|
If IS_DFS is false, the two steps above are done in reverse order
|
1106 |
|
|
(i.e., a breadth-first search). */
|
1107 |
|
|
|
1108 |
|
|
|
1109 |
|
|
void
|
1110 |
|
|
walk_use_def_chains (tree var, walk_use_def_chains_fn fn, void *data,
|
1111 |
|
|
bool is_dfs)
|
1112 |
|
|
{
|
1113 |
|
|
tree def_stmt;
|
1114 |
|
|
|
1115 |
|
|
gcc_assert (TREE_CODE (var) == SSA_NAME);
|
1116 |
|
|
|
1117 |
|
|
def_stmt = SSA_NAME_DEF_STMT (var);
|
1118 |
|
|
|
1119 |
|
|
/* We only need to recurse if the reaching definition comes from a PHI
|
1120 |
|
|
node. */
|
1121 |
|
|
if (TREE_CODE (def_stmt) != PHI_NODE)
|
1122 |
|
|
(*fn) (var, def_stmt, data);
|
1123 |
|
|
else
|
1124 |
|
|
{
|
1125 |
|
|
struct pointer_set_t *visited = pointer_set_create ();
|
1126 |
|
|
walk_use_def_chains_1 (var, fn, data, visited, is_dfs);
|
1127 |
|
|
pointer_set_destroy (visited);
|
1128 |
|
|
}
|
1129 |
|
|
}
|
1130 |
|
|
|
1131 |
|
|
|
1132 |
|
|
/* Emit warnings for uninitialized variables. This is done in two passes.
|
1133 |
|
|
|
1134 |
|
|
The first pass notices real uses of SSA names with default definitions.
|
1135 |
|
|
Such uses are unconditionally uninitialized, and we can be certain that
|
1136 |
|
|
such a use is a mistake. This pass is run before most optimizations,
|
1137 |
|
|
so that we catch as many as we can.
|
1138 |
|
|
|
1139 |
|
|
The second pass follows PHI nodes to find uses that are potentially
|
1140 |
|
|
uninitialized. In this case we can't necessarily prove that the use
|
1141 |
|
|
is really uninitialized. This pass is run after most optimizations,
|
1142 |
|
|
so that we thread as many jumps and possible, and delete as much dead
|
1143 |
|
|
code as possible, in order to reduce false positives. We also look
|
1144 |
|
|
again for plain uninitialized variables, since optimization may have
|
1145 |
|
|
changed conditionally uninitialized to unconditionally uninitialized. */
|
1146 |
|
|
|
1147 |
|
|
/* Emit a warning for T, an SSA_NAME, being uninitialized. The exact
|
1148 |
|
|
warning text is in MSGID and LOCUS may contain a location or be null. */
|
1149 |
|
|
|
1150 |
|
|
static void
|
1151 |
|
|
warn_uninit (tree t, const char *gmsgid, void *data)
|
1152 |
|
|
{
|
1153 |
|
|
tree var = SSA_NAME_VAR (t);
|
1154 |
|
|
tree def = SSA_NAME_DEF_STMT (t);
|
1155 |
|
|
tree context = (tree) data;
|
1156 |
|
|
location_t *locus, *fun_locus;
|
1157 |
|
|
|
1158 |
|
|
/* Default uses (indicated by an empty definition statement),
|
1159 |
|
|
are uninitialized. */
|
1160 |
|
|
if (!IS_EMPTY_STMT (def))
|
1161 |
|
|
return;
|
1162 |
|
|
|
1163 |
|
|
/* Except for PARMs of course, which are always initialized. */
|
1164 |
|
|
if (TREE_CODE (var) == PARM_DECL)
|
1165 |
|
|
return;
|
1166 |
|
|
|
1167 |
|
|
/* Hard register variables get their initial value from the ether. */
|
1168 |
|
|
if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var))
|
1169 |
|
|
return;
|
1170 |
|
|
|
1171 |
|
|
/* TREE_NO_WARNING either means we already warned, or the front end
|
1172 |
|
|
wishes to suppress the warning. */
|
1173 |
|
|
if (TREE_NO_WARNING (var))
|
1174 |
|
|
return;
|
1175 |
|
|
|
1176 |
|
|
locus = (context != NULL && EXPR_HAS_LOCATION (context)
|
1177 |
|
|
? EXPR_LOCUS (context)
|
1178 |
|
|
: &DECL_SOURCE_LOCATION (var));
|
1179 |
|
|
warning (0, gmsgid, locus, var);
|
1180 |
|
|
fun_locus = &DECL_SOURCE_LOCATION (cfun->decl);
|
1181 |
|
|
if (locus->file != fun_locus->file
|
1182 |
|
|
|| locus->line < fun_locus->line
|
1183 |
|
|
|| locus->line > cfun->function_end_locus.line)
|
1184 |
|
|
inform ("%J%qD was declared here", var, var);
|
1185 |
|
|
|
1186 |
|
|
TREE_NO_WARNING (var) = 1;
|
1187 |
|
|
}
|
1188 |
|
|
|
1189 |
|
|
/* Called via walk_tree, look for SSA_NAMEs that have empty definitions
|
1190 |
|
|
and warn about them. */
|
1191 |
|
|
|
1192 |
|
|
static tree
|
1193 |
|
|
warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data)
|
1194 |
|
|
{
|
1195 |
|
|
tree t = *tp;
|
1196 |
|
|
|
1197 |
|
|
switch (TREE_CODE (t))
|
1198 |
|
|
{
|
1199 |
|
|
case SSA_NAME:
|
1200 |
|
|
/* We only do data flow with SSA_NAMEs, so that's all we
|
1201 |
|
|
can warn about. */
|
1202 |
|
|
warn_uninit (t, "%H%qD is used uninitialized in this function", data);
|
1203 |
|
|
*walk_subtrees = 0;
|
1204 |
|
|
break;
|
1205 |
|
|
|
1206 |
|
|
case REALPART_EXPR:
|
1207 |
|
|
case IMAGPART_EXPR:
|
1208 |
|
|
/* The total store transformation performed during gimplification
|
1209 |
|
|
creates uninitialized variable uses. If all is well, these will
|
1210 |
|
|
be optimized away, so don't warn now. */
|
1211 |
|
|
if (TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME)
|
1212 |
|
|
*walk_subtrees = 0;
|
1213 |
|
|
break;
|
1214 |
|
|
|
1215 |
|
|
default:
|
1216 |
|
|
if (IS_TYPE_OR_DECL_P (t))
|
1217 |
|
|
*walk_subtrees = 0;
|
1218 |
|
|
break;
|
1219 |
|
|
}
|
1220 |
|
|
|
1221 |
|
|
return NULL_TREE;
|
1222 |
|
|
}
|
1223 |
|
|
|
1224 |
|
|
/* Look for inputs to PHI that are SSA_NAMEs that have empty definitions
|
1225 |
|
|
and warn about them. */
|
1226 |
|
|
|
1227 |
|
|
static void
|
1228 |
|
|
warn_uninitialized_phi (tree phi)
|
1229 |
|
|
{
|
1230 |
|
|
int i, n = PHI_NUM_ARGS (phi);
|
1231 |
|
|
|
1232 |
|
|
/* Don't look at memory tags. */
|
1233 |
|
|
if (!is_gimple_reg (PHI_RESULT (phi)))
|
1234 |
|
|
return;
|
1235 |
|
|
|
1236 |
|
|
for (i = 0; i < n; ++i)
|
1237 |
|
|
{
|
1238 |
|
|
tree op = PHI_ARG_DEF (phi, i);
|
1239 |
|
|
if (TREE_CODE (op) == SSA_NAME)
|
1240 |
|
|
warn_uninit (op, "%H%qD may be used uninitialized in this function",
|
1241 |
|
|
NULL);
|
1242 |
|
|
}
|
1243 |
|
|
}
|
1244 |
|
|
|
1245 |
|
|
static unsigned int
|
1246 |
|
|
execute_early_warn_uninitialized (void)
|
1247 |
|
|
{
|
1248 |
|
|
block_stmt_iterator bsi;
|
1249 |
|
|
basic_block bb;
|
1250 |
|
|
|
1251 |
|
|
FOR_EACH_BB (bb)
|
1252 |
|
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
1253 |
|
|
{
|
1254 |
|
|
tree context = bsi_stmt (bsi);
|
1255 |
|
|
walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var,
|
1256 |
|
|
context, NULL);
|
1257 |
|
|
}
|
1258 |
|
|
return 0;
|
1259 |
|
|
}
|
1260 |
|
|
|
1261 |
|
|
static unsigned int
|
1262 |
|
|
execute_late_warn_uninitialized (void)
|
1263 |
|
|
{
|
1264 |
|
|
basic_block bb;
|
1265 |
|
|
tree phi;
|
1266 |
|
|
|
1267 |
|
|
/* Re-do the plain uninitialized variable check, as optimization may have
|
1268 |
|
|
straightened control flow. Do this first so that we don't accidentally
|
1269 |
|
|
get a "may be" warning when we'd have seen an "is" warning later. */
|
1270 |
|
|
execute_early_warn_uninitialized ();
|
1271 |
|
|
|
1272 |
|
|
FOR_EACH_BB (bb)
|
1273 |
|
|
for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
|
1274 |
|
|
warn_uninitialized_phi (phi);
|
1275 |
|
|
return 0;
|
1276 |
|
|
}
|
1277 |
|
|
|
1278 |
|
|
static bool
|
1279 |
|
|
gate_warn_uninitialized (void)
|
1280 |
|
|
{
|
1281 |
|
|
return warn_uninitialized != 0;
|
1282 |
|
|
}
|
1283 |
|
|
|
1284 |
|
|
struct tree_opt_pass pass_early_warn_uninitialized =
|
1285 |
|
|
{
|
1286 |
|
|
NULL, /* name */
|
1287 |
|
|
gate_warn_uninitialized, /* gate */
|
1288 |
|
|
execute_early_warn_uninitialized, /* execute */
|
1289 |
|
|
NULL, /* sub */
|
1290 |
|
|
NULL, /* next */
|
1291 |
|
|
0, /* static_pass_number */
|
1292 |
|
|
0, /* tv_id */
|
1293 |
|
|
PROP_ssa, /* properties_required */
|
1294 |
|
|
0, /* properties_provided */
|
1295 |
|
|
0, /* properties_destroyed */
|
1296 |
|
|
0, /* todo_flags_start */
|
1297 |
|
|
0, /* todo_flags_finish */
|
1298 |
|
|
|
1299 |
|
|
};
|
1300 |
|
|
|
1301 |
|
|
struct tree_opt_pass pass_late_warn_uninitialized =
|
1302 |
|
|
{
|
1303 |
|
|
NULL, /* name */
|
1304 |
|
|
gate_warn_uninitialized, /* gate */
|
1305 |
|
|
execute_late_warn_uninitialized, /* execute */
|
1306 |
|
|
NULL, /* sub */
|
1307 |
|
|
NULL, /* next */
|
1308 |
|
|
0, /* static_pass_number */
|
1309 |
|
|
0, /* tv_id */
|
1310 |
|
|
PROP_ssa, /* properties_required */
|
1311 |
|
|
0, /* properties_provided */
|
1312 |
|
|
0, /* properties_destroyed */
|
1313 |
|
|
0, /* todo_flags_start */
|
1314 |
|
|
0, /* todo_flags_finish */
|
1315 |
|
|
|
1316 |
|
|
};
|
1317 |
|
|
|