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0
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1 /* __builtin_object_size (ptr, object_size_type) computation
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2 Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
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3 Contributed by Jakub Jelinek <jakub@redhat.com>
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4
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5 This file is part of GCC.
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6
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7 GCC is free software; you can redistribute it and/or modify
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8 it under the terms of the GNU General Public License as published by
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9 the Free Software Foundation; either version 3, or (at your option)
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10 any later version.
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11
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12 GCC is distributed in the hope that it will be useful,
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13 but WITHOUT ANY WARRANTY; without even the implied warranty of
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14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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15 GNU General Public License for more details.
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16
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17 You should have received a copy of the GNU General Public License
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18 along with GCC; see the file COPYING3. If not see
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19 <http://www.gnu.org/licenses/>. */
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20
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21 #include "config.h"
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22 #include "system.h"
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23 #include "coretypes.h"
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24 #include "tm.h"
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25 #include "tree.h"
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26 #include "toplev.h"
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27 #include "diagnostic.h"
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28 #include "tree-flow.h"
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29 #include "tree-pass.h"
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30 #include "tree-ssa-propagate.h"
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31
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32 struct object_size_info
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33 {
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34 int object_size_type;
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35 bitmap visited, reexamine;
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36 int pass;
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37 bool changed;
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38 unsigned int *depths;
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39 unsigned int *stack, *tos;
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40 };
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41
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42 static unsigned HOST_WIDE_INT unknown[4] = { -1, -1, 0, 0 };
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43
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44 static tree compute_object_offset (const_tree, const_tree);
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45 static unsigned HOST_WIDE_INT addr_object_size (const_tree, int);
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46 static unsigned HOST_WIDE_INT alloc_object_size (const_gimple, int);
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47 static tree pass_through_call (const_gimple);
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48 static void collect_object_sizes_for (struct object_size_info *, tree);
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49 static void expr_object_size (struct object_size_info *, tree, tree);
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50 static bool merge_object_sizes (struct object_size_info *, tree, tree,
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51 unsigned HOST_WIDE_INT);
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52 static bool plus_stmt_object_size (struct object_size_info *, tree, gimple);
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53 static bool cond_expr_object_size (struct object_size_info *, tree, tree);
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54 static unsigned int compute_object_sizes (void);
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55 static void init_offset_limit (void);
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56 static void check_for_plus_in_loops (struct object_size_info *, tree);
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57 static void check_for_plus_in_loops_1 (struct object_size_info *, tree,
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58 unsigned int);
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59
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60 /* object_sizes[0] is upper bound for number of bytes till the end of
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61 the object.
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62 object_sizes[1] is upper bound for number of bytes till the end of
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63 the subobject (innermost array or field with address taken).
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64 object_sizes[2] is lower bound for number of bytes till the end of
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65 the object and object_sizes[3] lower bound for subobject. */
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66 static unsigned HOST_WIDE_INT *object_sizes[4];
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67
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68 /* Bitmaps what object sizes have been computed already. */
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69 static bitmap computed[4];
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70
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71 /* Maximum value of offset we consider to be addition. */
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72 static unsigned HOST_WIDE_INT offset_limit;
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73
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74
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75 /* Initialize OFFSET_LIMIT variable. */
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76 static void
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77 init_offset_limit (void)
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78 {
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79 if (host_integerp (TYPE_MAX_VALUE (sizetype), 1))
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80 offset_limit = tree_low_cst (TYPE_MAX_VALUE (sizetype), 1);
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81 else
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82 offset_limit = -1;
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83 offset_limit /= 2;
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84 }
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85
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86
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87 /* Compute offset of EXPR within VAR. Return error_mark_node
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88 if unknown. */
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89
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90 static tree
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91 compute_object_offset (const_tree expr, const_tree var)
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92 {
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93 enum tree_code code = PLUS_EXPR;
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94 tree base, off, t;
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95
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96 if (expr == var)
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97 return size_zero_node;
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98
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99 switch (TREE_CODE (expr))
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100 {
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101 case COMPONENT_REF:
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102 base = compute_object_offset (TREE_OPERAND (expr, 0), var);
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103 if (base == error_mark_node)
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104 return base;
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105
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106 t = TREE_OPERAND (expr, 1);
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107 off = size_binop (PLUS_EXPR, DECL_FIELD_OFFSET (t),
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108 size_int (tree_low_cst (DECL_FIELD_BIT_OFFSET (t), 1)
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109 / BITS_PER_UNIT));
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110 break;
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111
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112 case REALPART_EXPR:
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113 CASE_CONVERT:
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114 case VIEW_CONVERT_EXPR:
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115 case NON_LVALUE_EXPR:
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116 return compute_object_offset (TREE_OPERAND (expr, 0), var);
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117
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118 case IMAGPART_EXPR:
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119 base = compute_object_offset (TREE_OPERAND (expr, 0), var);
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120 if (base == error_mark_node)
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121 return base;
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122
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123 off = TYPE_SIZE_UNIT (TREE_TYPE (expr));
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124 break;
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125
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126 case ARRAY_REF:
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127 base = compute_object_offset (TREE_OPERAND (expr, 0), var);
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128 if (base == error_mark_node)
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129 return base;
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130
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131 t = TREE_OPERAND (expr, 1);
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132 if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) < 0)
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133 {
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134 code = MINUS_EXPR;
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135 t = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t);
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136 }
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137 t = fold_convert (sizetype, t);
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138 off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t);
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139 break;
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140
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141 default:
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142 return error_mark_node;
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143 }
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144
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145 return size_binop (code, base, off);
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146 }
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147
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148
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149 /* Compute __builtin_object_size for PTR, which is a ADDR_EXPR.
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150 OBJECT_SIZE_TYPE is the second argument from __builtin_object_size.
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151 If unknown, return unknown[object_size_type]. */
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152
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153 static unsigned HOST_WIDE_INT
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154 addr_object_size (const_tree ptr, int object_size_type)
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155 {
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156 tree pt_var;
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157
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158 gcc_assert (TREE_CODE (ptr) == ADDR_EXPR);
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159
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160 pt_var = TREE_OPERAND (ptr, 0);
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161 if (REFERENCE_CLASS_P (pt_var))
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162 pt_var = get_base_address (pt_var);
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163
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164 if (pt_var
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165 && (SSA_VAR_P (pt_var) || TREE_CODE (pt_var) == STRING_CST)
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166 && TYPE_SIZE_UNIT (TREE_TYPE (pt_var))
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167 && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1)
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168 && (unsigned HOST_WIDE_INT)
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169 tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)), 1) < offset_limit)
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170 {
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171 tree bytes;
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172
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173 if (pt_var != TREE_OPERAND (ptr, 0))
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174 {
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175 tree var;
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176
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177 if (object_size_type & 1)
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178 {
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179 var = TREE_OPERAND (ptr, 0);
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180
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181 while (var != pt_var
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182 && TREE_CODE (var) != BIT_FIELD_REF
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183 && TREE_CODE (var) != COMPONENT_REF
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184 && TREE_CODE (var) != ARRAY_REF
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185 && TREE_CODE (var) != ARRAY_RANGE_REF
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186 && TREE_CODE (var) != REALPART_EXPR
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187 && TREE_CODE (var) != IMAGPART_EXPR)
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188 var = TREE_OPERAND (var, 0);
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189 if (var != pt_var && TREE_CODE (var) == ARRAY_REF)
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190 var = TREE_OPERAND (var, 0);
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191 if (! TYPE_SIZE_UNIT (TREE_TYPE (var))
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192 || ! host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (var)), 1)
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193 || tree_int_cst_lt (TYPE_SIZE_UNIT (TREE_TYPE (pt_var)),
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194 TYPE_SIZE_UNIT (TREE_TYPE (var))))
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195 var = pt_var;
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196 }
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197 else
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198 var = pt_var;
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199
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200 bytes = compute_object_offset (TREE_OPERAND (ptr, 0), var);
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201 if (bytes != error_mark_node)
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202 {
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203 if (TREE_CODE (bytes) == INTEGER_CST
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204 && tree_int_cst_lt (TYPE_SIZE_UNIT (TREE_TYPE (var)), bytes))
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205 bytes = size_zero_node;
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206 else
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207 bytes = size_binop (MINUS_EXPR,
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208 TYPE_SIZE_UNIT (TREE_TYPE (var)), bytes);
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209 }
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210 }
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211 else
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212 bytes = TYPE_SIZE_UNIT (TREE_TYPE (pt_var));
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213
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214 if (host_integerp (bytes, 1))
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215 return tree_low_cst (bytes, 1);
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216 }
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217
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218 return unknown[object_size_type];
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219 }
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220
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221
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222 /* Compute __builtin_object_size for CALL, which is a GIMPLE_CALL.
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223 Handles various allocation calls. OBJECT_SIZE_TYPE is the second
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224 argument from __builtin_object_size. If unknown, return
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225 unknown[object_size_type]. */
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226
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227 static unsigned HOST_WIDE_INT
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228 alloc_object_size (const_gimple call, int object_size_type)
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229 {
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230 tree callee, bytes = NULL_TREE;
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231 tree alloc_size;
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232 int arg1 = -1, arg2 = -1;
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233
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234 gcc_assert (is_gimple_call (call));
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235
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236 callee = gimple_call_fndecl (call);
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237 if (!callee)
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238 return unknown[object_size_type];
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239
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240 alloc_size = lookup_attribute ("alloc_size", TYPE_ATTRIBUTES (TREE_TYPE(callee)));
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241 if (alloc_size && TREE_VALUE (alloc_size))
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242 {
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243 tree p = TREE_VALUE (alloc_size);
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244
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245 arg1 = TREE_INT_CST_LOW (TREE_VALUE (p))-1;
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246 if (TREE_CHAIN (p))
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247 arg2 = TREE_INT_CST_LOW (TREE_VALUE (TREE_CHAIN (p)))-1;
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248 }
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249
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250 if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL)
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251 switch (DECL_FUNCTION_CODE (callee))
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252 {
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253 case BUILT_IN_CALLOC:
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254 arg2 = 1;
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255 /* fall through */
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256 case BUILT_IN_MALLOC:
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257 case BUILT_IN_ALLOCA:
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258 arg1 = 0;
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259 default:
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260 break;
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261 }
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262
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263 if (arg1 < 0 || arg1 >= (int)gimple_call_num_args (call)
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264 || TREE_CODE (gimple_call_arg (call, arg1)) != INTEGER_CST
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265 || (arg2 >= 0
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266 && (arg2 >= (int)gimple_call_num_args (call)
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267 || TREE_CODE (gimple_call_arg (call, arg2)) != INTEGER_CST)))
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268 return unknown[object_size_type];
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269
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270 if (arg2 >= 0)
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271 bytes = size_binop (MULT_EXPR,
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272 fold_convert (sizetype, gimple_call_arg (call, arg1)),
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273 fold_convert (sizetype, gimple_call_arg (call, arg2)));
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274 else if (arg1 >= 0)
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275 bytes = fold_convert (sizetype, gimple_call_arg (call, arg1));
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276
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277 if (bytes && host_integerp (bytes, 1))
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278 return tree_low_cst (bytes, 1);
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279
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280 return unknown[object_size_type];
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281 }
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282
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283
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284 /* If object size is propagated from one of function's arguments directly
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285 to its return value, return that argument for GIMPLE_CALL statement CALL.
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286 Otherwise return NULL. */
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287
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288 static tree
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289 pass_through_call (const_gimple call)
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290 {
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291 tree callee = gimple_call_fndecl (call);
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292
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293 if (callee
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294 && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL)
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295 switch (DECL_FUNCTION_CODE (callee))
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296 {
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297 case BUILT_IN_MEMCPY:
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298 case BUILT_IN_MEMMOVE:
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299 case BUILT_IN_MEMSET:
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300 case BUILT_IN_STRCPY:
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301 case BUILT_IN_STRNCPY:
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302 case BUILT_IN_STRCAT:
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303 case BUILT_IN_STRNCAT:
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304 case BUILT_IN_MEMCPY_CHK:
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305 case BUILT_IN_MEMMOVE_CHK:
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306 case BUILT_IN_MEMSET_CHK:
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307 case BUILT_IN_STRCPY_CHK:
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308 case BUILT_IN_STRNCPY_CHK:
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309 case BUILT_IN_STRCAT_CHK:
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310 case BUILT_IN_STRNCAT_CHK:
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311 if (gimple_call_num_args (call) >= 1)
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312 return gimple_call_arg (call, 0);
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313 break;
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314 default:
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315 break;
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316 }
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317
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318 return NULL_TREE;
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319 }
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320
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321
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322 /* Compute __builtin_object_size value for PTR. OBJECT_SIZE_TYPE is the
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323 second argument from __builtin_object_size. */
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324
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325 unsigned HOST_WIDE_INT
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326 compute_builtin_object_size (tree ptr, int object_size_type)
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327 {
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328 gcc_assert (object_size_type >= 0 && object_size_type <= 3);
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329
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330 if (! offset_limit)
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331 init_offset_limit ();
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332
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333 if (TREE_CODE (ptr) == ADDR_EXPR)
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334 return addr_object_size (ptr, object_size_type);
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335
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336 if (TREE_CODE (ptr) == SSA_NAME
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337 && POINTER_TYPE_P (TREE_TYPE (ptr))
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338 && object_sizes[object_size_type] != NULL)
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339 {
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340 if (!bitmap_bit_p (computed[object_size_type], SSA_NAME_VERSION (ptr)))
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341 {
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342 struct object_size_info osi;
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343 bitmap_iterator bi;
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344 unsigned int i;
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345
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346 if (dump_file)
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347 {
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348 fprintf (dump_file, "Computing %s %sobject size for ",
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349 (object_size_type & 2) ? "minimum" : "maximum",
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350 (object_size_type & 1) ? "sub" : "");
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351 print_generic_expr (dump_file, ptr, dump_flags);
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352 fprintf (dump_file, ":\n");
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353 }
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354
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355 osi.visited = BITMAP_ALLOC (NULL);
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356 osi.reexamine = BITMAP_ALLOC (NULL);
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357 osi.object_size_type = object_size_type;
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358 osi.depths = NULL;
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359 osi.stack = NULL;
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360 osi.tos = NULL;
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361
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362 /* First pass: walk UD chains, compute object sizes that
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363 can be computed. osi.reexamine bitmap at the end will
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364 contain what variables were found in dependency cycles
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365 and therefore need to be reexamined. */
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366 osi.pass = 0;
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367 osi.changed = false;
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368 collect_object_sizes_for (&osi, ptr);
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369
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370 /* Second pass: keep recomputing object sizes of variables
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371 that need reexamination, until no object sizes are
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372 increased or all object sizes are computed. */
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373 if (! bitmap_empty_p (osi.reexamine))
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374 {
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375 bitmap reexamine = BITMAP_ALLOC (NULL);
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376
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377 /* If looking for minimum instead of maximum object size,
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378 detect cases where a pointer is increased in a loop.
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379 Although even without this detection pass 2 would eventually
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380 terminate, it could take a long time. If a pointer is
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381 increasing this way, we need to assume 0 object size.
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382 E.g. p = &buf[0]; while (cond) p = p + 4; */
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383 if (object_size_type & 2)
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384 {
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385 osi.depths = XCNEWVEC (unsigned int, num_ssa_names);
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386 osi.stack = XNEWVEC (unsigned int, num_ssa_names);
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387 osi.tos = osi.stack;
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388 osi.pass = 1;
|
|
|
389 /* collect_object_sizes_for is changing
|
|
|
390 osi.reexamine bitmap, so iterate over a copy. */
|
|
|
391 bitmap_copy (reexamine, osi.reexamine);
|
|
|
392 EXECUTE_IF_SET_IN_BITMAP (reexamine, 0, i, bi)
|
|
|
393 if (bitmap_bit_p (osi.reexamine, i))
|
|
|
394 check_for_plus_in_loops (&osi, ssa_name (i));
|
|
|
395
|
|
|
396 free (osi.depths);
|
|
|
397 osi.depths = NULL;
|
|
|
398 free (osi.stack);
|
|
|
399 osi.stack = NULL;
|
|
|
400 osi.tos = NULL;
|
|
|
401 }
|
|
|
402
|
|
|
403 do
|
|
|
404 {
|
|
|
405 osi.pass = 2;
|
|
|
406 osi.changed = false;
|
|
|
407 /* collect_object_sizes_for is changing
|
|
|
408 osi.reexamine bitmap, so iterate over a copy. */
|
|
|
409 bitmap_copy (reexamine, osi.reexamine);
|
|
|
410 EXECUTE_IF_SET_IN_BITMAP (reexamine, 0, i, bi)
|
|
|
411 if (bitmap_bit_p (osi.reexamine, i))
|
|
|
412 {
|
|
|
413 collect_object_sizes_for (&osi, ssa_name (i));
|
|
|
414 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
415 {
|
|
|
416 fprintf (dump_file, "Reexamining ");
|
|
|
417 print_generic_expr (dump_file, ssa_name (i),
|
|
|
418 dump_flags);
|
|
|
419 fprintf (dump_file, "\n");
|
|
|
420 }
|
|
|
421 }
|
|
|
422 }
|
|
|
423 while (osi.changed);
|
|
|
424
|
|
|
425 BITMAP_FREE (reexamine);
|
|
|
426 }
|
|
|
427 EXECUTE_IF_SET_IN_BITMAP (osi.reexamine, 0, i, bi)
|
|
|
428 bitmap_set_bit (computed[object_size_type], i);
|
|
|
429
|
|
|
430 /* Debugging dumps. */
|
|
|
431 if (dump_file)
|
|
|
432 {
|
|
|
433 EXECUTE_IF_SET_IN_BITMAP (osi.visited, 0, i, bi)
|
|
|
434 if (object_sizes[object_size_type][i]
|
|
|
435 != unknown[object_size_type])
|
|
|
436 {
|
|
|
437 print_generic_expr (dump_file, ssa_name (i),
|
|
|
438 dump_flags);
|
|
|
439 fprintf (dump_file,
|
|
|
440 ": %s %sobject size "
|
|
|
441 HOST_WIDE_INT_PRINT_UNSIGNED "\n",
|
|
|
442 (object_size_type & 2) ? "minimum" : "maximum",
|
|
|
443 (object_size_type & 1) ? "sub" : "",
|
|
|
444 object_sizes[object_size_type][i]);
|
|
|
445 }
|
|
|
446 }
|
|
|
447
|
|
|
448 BITMAP_FREE (osi.reexamine);
|
|
|
449 BITMAP_FREE (osi.visited);
|
|
|
450 }
|
|
|
451
|
|
|
452 return object_sizes[object_size_type][SSA_NAME_VERSION (ptr)];
|
|
|
453 }
|
|
|
454
|
|
|
455 return unknown[object_size_type];
|
|
|
456 }
|
|
|
457
|
|
|
458 /* Compute object_sizes for PTR, defined to VALUE, which is not an SSA_NAME. */
|
|
|
459
|
|
|
460 static void
|
|
|
461 expr_object_size (struct object_size_info *osi, tree ptr, tree value)
|
|
|
462 {
|
|
|
463 int object_size_type = osi->object_size_type;
|
|
|
464 unsigned int varno = SSA_NAME_VERSION (ptr);
|
|
|
465 unsigned HOST_WIDE_INT bytes;
|
|
|
466
|
|
|
467 gcc_assert (object_sizes[object_size_type][varno]
|
|
|
468 != unknown[object_size_type]);
|
|
|
469 gcc_assert (osi->pass == 0);
|
|
|
470
|
|
|
471 if (TREE_CODE (value) == WITH_SIZE_EXPR)
|
|
|
472 value = TREE_OPERAND (value, 0);
|
|
|
473
|
|
|
474 /* Pointer variables should have been handled by merge_object_sizes. */
|
|
|
475 gcc_assert (TREE_CODE (value) != SSA_NAME
|
|
|
476 || !POINTER_TYPE_P (TREE_TYPE (value)));
|
|
|
477
|
|
|
478 if (TREE_CODE (value) == ADDR_EXPR)
|
|
|
479 bytes = addr_object_size (value, object_size_type);
|
|
|
480 else
|
|
|
481 bytes = unknown[object_size_type];
|
|
|
482
|
|
|
483 if ((object_size_type & 2) == 0)
|
|
|
484 {
|
|
|
485 if (object_sizes[object_size_type][varno] < bytes)
|
|
|
486 object_sizes[object_size_type][varno] = bytes;
|
|
|
487 }
|
|
|
488 else
|
|
|
489 {
|
|
|
490 if (object_sizes[object_size_type][varno] > bytes)
|
|
|
491 object_sizes[object_size_type][varno] = bytes;
|
|
|
492 }
|
|
|
493 }
|
|
|
494
|
|
|
495
|
|
|
496 /* Compute object_sizes for PTR, defined to the result of a call. */
|
|
|
497
|
|
|
498 static void
|
|
|
499 call_object_size (struct object_size_info *osi, tree ptr, gimple call)
|
|
|
500 {
|
|
|
501 int object_size_type = osi->object_size_type;
|
|
|
502 unsigned int varno = SSA_NAME_VERSION (ptr);
|
|
|
503 unsigned HOST_WIDE_INT bytes;
|
|
|
504
|
|
|
505 gcc_assert (is_gimple_call (call));
|
|
|
506
|
|
|
507 gcc_assert (object_sizes[object_size_type][varno]
|
|
|
508 != unknown[object_size_type]);
|
|
|
509 gcc_assert (osi->pass == 0);
|
|
|
510
|
|
|
511 bytes = alloc_object_size (call, object_size_type);
|
|
|
512
|
|
|
513 if ((object_size_type & 2) == 0)
|
|
|
514 {
|
|
|
515 if (object_sizes[object_size_type][varno] < bytes)
|
|
|
516 object_sizes[object_size_type][varno] = bytes;
|
|
|
517 }
|
|
|
518 else
|
|
|
519 {
|
|
|
520 if (object_sizes[object_size_type][varno] > bytes)
|
|
|
521 object_sizes[object_size_type][varno] = bytes;
|
|
|
522 }
|
|
|
523 }
|
|
|
524
|
|
|
525
|
|
|
526 /* Compute object_sizes for PTR, defined to an unknown value. */
|
|
|
527
|
|
|
528 static void
|
|
|
529 unknown_object_size (struct object_size_info *osi, tree ptr)
|
|
|
530 {
|
|
|
531 int object_size_type = osi->object_size_type;
|
|
|
532 unsigned int varno = SSA_NAME_VERSION (ptr);
|
|
|
533 unsigned HOST_WIDE_INT bytes;
|
|
|
534
|
|
|
535 gcc_assert (object_sizes[object_size_type][varno]
|
|
|
536 != unknown[object_size_type]);
|
|
|
537 gcc_assert (osi->pass == 0);
|
|
|
538
|
|
|
539 bytes = unknown[object_size_type];
|
|
|
540
|
|
|
541 if ((object_size_type & 2) == 0)
|
|
|
542 {
|
|
|
543 if (object_sizes[object_size_type][varno] < bytes)
|
|
|
544 object_sizes[object_size_type][varno] = bytes;
|
|
|
545 }
|
|
|
546 else
|
|
|
547 {
|
|
|
548 if (object_sizes[object_size_type][varno] > bytes)
|
|
|
549 object_sizes[object_size_type][varno] = bytes;
|
|
|
550 }
|
|
|
551 }
|
|
|
552
|
|
|
553
|
|
|
554 /* Merge object sizes of ORIG + OFFSET into DEST. Return true if
|
|
|
555 the object size might need reexamination later. */
|
|
|
556
|
|
|
557 static bool
|
|
|
558 merge_object_sizes (struct object_size_info *osi, tree dest, tree orig,
|
|
|
559 unsigned HOST_WIDE_INT offset)
|
|
|
560 {
|
|
|
561 int object_size_type = osi->object_size_type;
|
|
|
562 unsigned int varno = SSA_NAME_VERSION (dest);
|
|
|
563 unsigned HOST_WIDE_INT orig_bytes;
|
|
|
564
|
|
|
565 if (object_sizes[object_size_type][varno] == unknown[object_size_type])
|
|
|
566 return false;
|
|
|
567 if (offset >= offset_limit)
|
|
|
568 {
|
|
|
569 object_sizes[object_size_type][varno] = unknown[object_size_type];
|
|
|
570 return false;
|
|
|
571 }
|
|
|
572
|
|
|
573 if (osi->pass == 0)
|
|
|
574 collect_object_sizes_for (osi, orig);
|
|
|
575
|
|
|
576 orig_bytes = object_sizes[object_size_type][SSA_NAME_VERSION (orig)];
|
|
|
577 if (orig_bytes != unknown[object_size_type])
|
|
|
578 orig_bytes = (offset > orig_bytes)
|
|
|
579 ? (unsigned HOST_WIDE_INT) 0 : orig_bytes - offset;
|
|
|
580
|
|
|
581 if ((object_size_type & 2) == 0)
|
|
|
582 {
|
|
|
583 if (object_sizes[object_size_type][varno] < orig_bytes)
|
|
|
584 {
|
|
|
585 object_sizes[object_size_type][varno] = orig_bytes;
|
|
|
586 osi->changed = true;
|
|
|
587 }
|
|
|
588 }
|
|
|
589 else
|
|
|
590 {
|
|
|
591 if (object_sizes[object_size_type][varno] > orig_bytes)
|
|
|
592 {
|
|
|
593 object_sizes[object_size_type][varno] = orig_bytes;
|
|
|
594 osi->changed = true;
|
|
|
595 }
|
|
|
596 }
|
|
|
597 return bitmap_bit_p (osi->reexamine, SSA_NAME_VERSION (orig));
|
|
|
598 }
|
|
|
599
|
|
|
600
|
|
|
601 /* Compute object_sizes for VAR, defined to the result of an assignment
|
|
|
602 with operator POINTER_PLUS_EXPR. Return true if the object size might
|
|
|
603 need reexamination later. */
|
|
|
604
|
|
|
605 static bool
|
|
|
606 plus_stmt_object_size (struct object_size_info *osi, tree var, gimple stmt)
|
|
|
607 {
|
|
|
608 int object_size_type = osi->object_size_type;
|
|
|
609 unsigned int varno = SSA_NAME_VERSION (var);
|
|
|
610 unsigned HOST_WIDE_INT bytes;
|
|
|
611 tree op0, op1;
|
|
|
612
|
|
|
613 gcc_assert (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR);
|
|
|
614
|
|
|
615 op0 = gimple_assign_rhs1 (stmt);
|
|
|
616 op1 = gimple_assign_rhs2 (stmt);
|
|
|
617
|
|
|
618 if (object_sizes[object_size_type][varno] == unknown[object_size_type])
|
|
|
619 return false;
|
|
|
620
|
|
|
621 /* Handle PTR + OFFSET here. */
|
|
|
622 if (TREE_CODE (op1) == INTEGER_CST
|
|
|
623 && (TREE_CODE (op0) == SSA_NAME
|
|
|
624 || TREE_CODE (op0) == ADDR_EXPR))
|
|
|
625 {
|
|
|
626 if (! host_integerp (op1, 1))
|
|
|
627 bytes = unknown[object_size_type];
|
|
|
628 else if (TREE_CODE (op0) == SSA_NAME)
|
|
|
629 return merge_object_sizes (osi, var, op0, tree_low_cst (op1, 1));
|
|
|
630 else
|
|
|
631 {
|
|
|
632 unsigned HOST_WIDE_INT off = tree_low_cst (op1, 1);
|
|
|
633
|
|
|
634 /* op0 will be ADDR_EXPR here. */
|
|
|
635 bytes = compute_builtin_object_size (op0, object_size_type);
|
|
|
636 if (bytes == unknown[object_size_type])
|
|
|
637 ;
|
|
|
638 else if (off > offset_limit)
|
|
|
639 bytes = unknown[object_size_type];
|
|
|
640 else if (off > bytes)
|
|
|
641 bytes = 0;
|
|
|
642 else
|
|
|
643 bytes -= off;
|
|
|
644 }
|
|
|
645 }
|
|
|
646 else
|
|
|
647 bytes = unknown[object_size_type];
|
|
|
648
|
|
|
649 if ((object_size_type & 2) == 0)
|
|
|
650 {
|
|
|
651 if (object_sizes[object_size_type][varno] < bytes)
|
|
|
652 object_sizes[object_size_type][varno] = bytes;
|
|
|
653 }
|
|
|
654 else
|
|
|
655 {
|
|
|
656 if (object_sizes[object_size_type][varno] > bytes)
|
|
|
657 object_sizes[object_size_type][varno] = bytes;
|
|
|
658 }
|
|
|
659 return false;
|
|
|
660 }
|
|
|
661
|
|
|
662
|
|
|
663 /* Compute object_sizes for VAR, defined to VALUE, which is
|
|
|
664 a COND_EXPR. Return true if the object size might need reexamination
|
|
|
665 later. */
|
|
|
666
|
|
|
667 static bool
|
|
|
668 cond_expr_object_size (struct object_size_info *osi, tree var, tree value)
|
|
|
669 {
|
|
|
670 tree then_, else_;
|
|
|
671 int object_size_type = osi->object_size_type;
|
|
|
672 unsigned int varno = SSA_NAME_VERSION (var);
|
|
|
673 bool reexamine = false;
|
|
|
674
|
|
|
675 gcc_assert (TREE_CODE (value) == COND_EXPR);
|
|
|
676
|
|
|
677 if (object_sizes[object_size_type][varno] == unknown[object_size_type])
|
|
|
678 return false;
|
|
|
679
|
|
|
680 then_ = COND_EXPR_THEN (value);
|
|
|
681 else_ = COND_EXPR_ELSE (value);
|
|
|
682
|
|
|
683 if (TREE_CODE (then_) == SSA_NAME)
|
|
|
684 reexamine |= merge_object_sizes (osi, var, then_, 0);
|
|
|
685 else
|
|
|
686 expr_object_size (osi, var, then_);
|
|
|
687
|
|
|
688 if (TREE_CODE (else_) == SSA_NAME)
|
|
|
689 reexamine |= merge_object_sizes (osi, var, else_, 0);
|
|
|
690 else
|
|
|
691 expr_object_size (osi, var, else_);
|
|
|
692
|
|
|
693 return reexamine;
|
|
|
694 }
|
|
|
695
|
|
|
696 /* Compute object sizes for VAR.
|
|
|
697 For ADDR_EXPR an object size is the number of remaining bytes
|
|
|
698 to the end of the object (where what is considered an object depends on
|
|
|
699 OSI->object_size_type).
|
|
|
700 For allocation GIMPLE_CALL like malloc or calloc object size is the size
|
|
|
701 of the allocation.
|
|
|
702 For POINTER_PLUS_EXPR where second operand is a constant integer,
|
|
|
703 object size is object size of the first operand minus the constant.
|
|
|
704 If the constant is bigger than the number of remaining bytes until the
|
|
|
705 end of the object, object size is 0, but if it is instead a pointer
|
|
|
706 subtraction, object size is unknown[object_size_type].
|
|
|
707 To differentiate addition from subtraction, ADDR_EXPR returns
|
|
|
708 unknown[object_size_type] for all objects bigger than half of the address
|
|
|
709 space, and constants less than half of the address space are considered
|
|
|
710 addition, while bigger constants subtraction.
|
|
|
711 For a memcpy like GIMPLE_CALL that always returns one of its arguments, the
|
|
|
712 object size is object size of that argument.
|
|
|
713 Otherwise, object size is the maximum of object sizes of variables
|
|
|
714 that it might be set to. */
|
|
|
715
|
|
|
716 static void
|
|
|
717 collect_object_sizes_for (struct object_size_info *osi, tree var)
|
|
|
718 {
|
|
|
719 int object_size_type = osi->object_size_type;
|
|
|
720 unsigned int varno = SSA_NAME_VERSION (var);
|
|
|
721 gimple stmt;
|
|
|
722 bool reexamine;
|
|
|
723
|
|
|
724 if (bitmap_bit_p (computed[object_size_type], varno))
|
|
|
725 return;
|
|
|
726
|
|
|
727 if (osi->pass == 0)
|
|
|
728 {
|
|
|
729 if (! bitmap_bit_p (osi->visited, varno))
|
|
|
730 {
|
|
|
731 bitmap_set_bit (osi->visited, varno);
|
|
|
732 object_sizes[object_size_type][varno]
|
|
|
733 = (object_size_type & 2) ? -1 : 0;
|
|
|
734 }
|
|
|
735 else
|
|
|
736 {
|
|
|
737 /* Found a dependency loop. Mark the variable for later
|
|
|
738 re-examination. */
|
|
|
739 bitmap_set_bit (osi->reexamine, varno);
|
|
|
740 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
741 {
|
|
|
742 fprintf (dump_file, "Found a dependency loop at ");
|
|
|
743 print_generic_expr (dump_file, var, dump_flags);
|
|
|
744 fprintf (dump_file, "\n");
|
|
|
745 }
|
|
|
746 return;
|
|
|
747 }
|
|
|
748 }
|
|
|
749
|
|
|
750 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
751 {
|
|
|
752 fprintf (dump_file, "Visiting use-def links for ");
|
|
|
753 print_generic_expr (dump_file, var, dump_flags);
|
|
|
754 fprintf (dump_file, "\n");
|
|
|
755 }
|
|
|
756
|
|
|
757 stmt = SSA_NAME_DEF_STMT (var);
|
|
|
758 reexamine = false;
|
|
|
759
|
|
|
760 switch (gimple_code (stmt))
|
|
|
761 {
|
|
|
762 case GIMPLE_ASSIGN:
|
|
|
763 {
|
|
|
764 if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
|
|
|
765 reexamine = plus_stmt_object_size (osi, var, stmt);
|
|
|
766 else if (gimple_assign_single_p (stmt)
|
|
|
767 || gimple_assign_unary_nop_p (stmt))
|
|
|
768 {
|
|
|
769 tree rhs = gimple_assign_rhs1 (stmt);
|
|
|
770
|
|
|
771 if (TREE_CODE (rhs) == SSA_NAME
|
|
|
772 && POINTER_TYPE_P (TREE_TYPE (rhs)))
|
|
|
773 reexamine = merge_object_sizes (osi, var, rhs, 0);
|
|
|
774 else if (TREE_CODE (rhs) == COND_EXPR)
|
|
|
775 reexamine = cond_expr_object_size (osi, var, rhs);
|
|
|
776 else
|
|
|
777 expr_object_size (osi, var, rhs);
|
|
|
778 }
|
|
|
779 else
|
|
|
780 unknown_object_size (osi, var);
|
|
|
781 break;
|
|
|
782 }
|
|
|
783
|
|
|
784 case GIMPLE_CALL:
|
|
|
785 {
|
|
|
786 tree arg = pass_through_call (stmt);
|
|
|
787 if (arg)
|
|
|
788 {
|
|
|
789 if (TREE_CODE (arg) == SSA_NAME
|
|
|
790 && POINTER_TYPE_P (TREE_TYPE (arg)))
|
|
|
791 reexamine = merge_object_sizes (osi, var, arg, 0);
|
|
|
792 else if (TREE_CODE (arg) == COND_EXPR)
|
|
|
793 reexamine = cond_expr_object_size (osi, var, arg);
|
|
|
794 else
|
|
|
795 expr_object_size (osi, var, arg);
|
|
|
796 }
|
|
|
797 else
|
|
|
798 call_object_size (osi, var, stmt);
|
|
|
799 break;
|
|
|
800 }
|
|
|
801
|
|
|
802 case GIMPLE_ASM:
|
|
|
803 /* Pointers defined by __asm__ statements can point anywhere. */
|
|
|
804 object_sizes[object_size_type][varno] = unknown[object_size_type];
|
|
|
805 break;
|
|
|
806
|
|
|
807 case GIMPLE_NOP:
|
|
|
808 {
|
|
|
809 tree decl = SSA_NAME_VAR (var);
|
|
|
810
|
|
|
811 if (TREE_CODE (decl) != PARM_DECL && DECL_INITIAL (decl))
|
|
|
812 expr_object_size (osi, var, DECL_INITIAL (decl));
|
|
|
813 else
|
|
|
814 expr_object_size (osi, var, decl);
|
|
|
815 }
|
|
|
816 break;
|
|
|
817
|
|
|
818 case GIMPLE_PHI:
|
|
|
819 {
|
|
|
820 unsigned i;
|
|
|
821
|
|
|
822 for (i = 0; i < gimple_phi_num_args (stmt); i++)
|
|
|
823 {
|
|
|
824 tree rhs = gimple_phi_arg (stmt, i)->def;
|
|
|
825
|
|
|
826 if (object_sizes[object_size_type][varno]
|
|
|
827 == unknown[object_size_type])
|
|
|
828 break;
|
|
|
829
|
|
|
830 if (TREE_CODE (rhs) == SSA_NAME)
|
|
|
831 reexamine |= merge_object_sizes (osi, var, rhs, 0);
|
|
|
832 else if (osi->pass == 0)
|
|
|
833 expr_object_size (osi, var, rhs);
|
|
|
834 }
|
|
|
835 break;
|
|
|
836 }
|
|
|
837
|
|
|
838 default:
|
|
|
839 gcc_unreachable ();
|
|
|
840 }
|
|
|
841
|
|
|
842 if (! reexamine
|
|
|
843 || object_sizes[object_size_type][varno] == unknown[object_size_type])
|
|
|
844 {
|
|
|
845 bitmap_set_bit (computed[object_size_type], varno);
|
|
|
846 bitmap_clear_bit (osi->reexamine, varno);
|
|
|
847 }
|
|
|
848 else
|
|
|
849 {
|
|
|
850 bitmap_set_bit (osi->reexamine, varno);
|
|
|
851 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
852 {
|
|
|
853 fprintf (dump_file, "Need to reexamine ");
|
|
|
854 print_generic_expr (dump_file, var, dump_flags);
|
|
|
855 fprintf (dump_file, "\n");
|
|
|
856 }
|
|
|
857 }
|
|
|
858 }
|
|
|
859
|
|
|
860
|
|
|
861 /* Helper function for check_for_plus_in_loops. Called recursively
|
|
|
862 to detect loops. */
|
|
|
863
|
|
|
864 static void
|
|
|
865 check_for_plus_in_loops_1 (struct object_size_info *osi, tree var,
|
|
|
866 unsigned int depth)
|
|
|
867 {
|
|
|
868 gimple stmt = SSA_NAME_DEF_STMT (var);
|
|
|
869 unsigned int varno = SSA_NAME_VERSION (var);
|
|
|
870
|
|
|
871 if (osi->depths[varno])
|
|
|
872 {
|
|
|
873 if (osi->depths[varno] != depth)
|
|
|
874 {
|
|
|
875 unsigned int *sp;
|
|
|
876
|
|
|
877 /* Found a loop involving pointer addition. */
|
|
|
878 for (sp = osi->tos; sp > osi->stack; )
|
|
|
879 {
|
|
|
880 --sp;
|
|
|
881 bitmap_clear_bit (osi->reexamine, *sp);
|
|
|
882 bitmap_set_bit (computed[osi->object_size_type], *sp);
|
|
|
883 object_sizes[osi->object_size_type][*sp] = 0;
|
|
|
884 if (*sp == varno)
|
|
|
885 break;
|
|
|
886 }
|
|
|
887 }
|
|
|
888 return;
|
|
|
889 }
|
|
|
890 else if (! bitmap_bit_p (osi->reexamine, varno))
|
|
|
891 return;
|
|
|
892
|
|
|
893 osi->depths[varno] = depth;
|
|
|
894 *osi->tos++ = varno;
|
|
|
895
|
|
|
896 switch (gimple_code (stmt))
|
|
|
897 {
|
|
|
898
|
|
|
899 case GIMPLE_ASSIGN:
|
|
|
900 {
|
|
|
901 if ((gimple_assign_single_p (stmt)
|
|
|
902 || gimple_assign_unary_nop_p (stmt))
|
|
|
903 && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME)
|
|
|
904 {
|
|
|
905 tree rhs = gimple_assign_rhs1 (stmt);
|
|
|
906
|
|
|
907 check_for_plus_in_loops_1 (osi, rhs, depth);
|
|
|
908 }
|
|
|
909 else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
|
|
|
910 {
|
|
|
911 tree basevar = gimple_assign_rhs1 (stmt);
|
|
|
912 tree cst = gimple_assign_rhs2 (stmt);
|
|
|
913
|
|
|
914 gcc_assert (TREE_CODE (cst) == INTEGER_CST);
|
|
|
915
|
|
|
916 check_for_plus_in_loops_1 (osi, basevar,
|
|
|
917 depth + !integer_zerop (cst));
|
|
|
918 }
|
|
|
919 else
|
|
|
920 gcc_unreachable ();
|
|
|
921 break;
|
|
|
922 }
|
|
|
923
|
|
|
924 case GIMPLE_CALL:
|
|
|
925 {
|
|
|
926 tree arg = pass_through_call (stmt);
|
|
|
927 if (arg)
|
|
|
928 {
|
|
|
929 if (TREE_CODE (arg) == SSA_NAME)
|
|
|
930 check_for_plus_in_loops_1 (osi, arg, depth);
|
|
|
931 else
|
|
|
932 gcc_unreachable ();
|
|
|
933 }
|
|
|
934 break;
|
|
|
935 }
|
|
|
936
|
|
|
937 case GIMPLE_PHI:
|
|
|
938 {
|
|
|
939 unsigned i;
|
|
|
940
|
|
|
941 for (i = 0; i < gimple_phi_num_args (stmt); i++)
|
|
|
942 {
|
|
|
943 tree rhs = gimple_phi_arg (stmt, i)->def;
|
|
|
944
|
|
|
945 if (TREE_CODE (rhs) == SSA_NAME)
|
|
|
946 check_for_plus_in_loops_1 (osi, rhs, depth);
|
|
|
947 }
|
|
|
948 break;
|
|
|
949 }
|
|
|
950
|
|
|
951 default:
|
|
|
952 gcc_unreachable ();
|
|
|
953 }
|
|
|
954
|
|
|
955 osi->depths[varno] = 0;
|
|
|
956 osi->tos--;
|
|
|
957 }
|
|
|
958
|
|
|
959
|
|
|
960 /* Check if some pointer we are computing object size of is being increased
|
|
|
961 within a loop. If yes, assume all the SSA variables participating in
|
|
|
962 that loop have minimum object sizes 0. */
|
|
|
963
|
|
|
964 static void
|
|
|
965 check_for_plus_in_loops (struct object_size_info *osi, tree var)
|
|
|
966 {
|
|
|
967 gimple stmt = SSA_NAME_DEF_STMT (var);
|
|
|
968
|
|
|
969 /* NOTE: In the pre-tuples code, we handled a CALL_EXPR here,
|
|
|
970 and looked for a POINTER_PLUS_EXPR in the pass-through
|
|
|
971 argument, if any. In GIMPLE, however, such an expression
|
|
|
972 is not a valid call operand. */
|
|
|
973
|
|
|
974 if (is_gimple_assign (stmt)
|
|
|
975 && gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
|
|
|
976 {
|
|
|
977 tree basevar = gimple_assign_rhs1 (stmt);
|
|
|
978 tree cst = gimple_assign_rhs2 (stmt);
|
|
|
979
|
|
|
980 gcc_assert (TREE_CODE (cst) == INTEGER_CST);
|
|
|
981
|
|
|
982 if (integer_zerop (cst))
|
|
|
983 return;
|
|
|
984
|
|
|
985 osi->depths[SSA_NAME_VERSION (basevar)] = 1;
|
|
|
986 *osi->tos++ = SSA_NAME_VERSION (basevar);
|
|
|
987 check_for_plus_in_loops_1 (osi, var, 2);
|
|
|
988 osi->depths[SSA_NAME_VERSION (basevar)] = 0;
|
|
|
989 osi->tos--;
|
|
|
990 }
|
|
|
991 }
|
|
|
992
|
|
|
993
|
|
|
994 /* Initialize data structures for the object size computation. */
|
|
|
995
|
|
|
996 void
|
|
|
997 init_object_sizes (void)
|
|
|
998 {
|
|
|
999 int object_size_type;
|
|
|
1000
|
|
|
1001 if (object_sizes[0])
|
|
|
1002 return;
|
|
|
1003
|
|
|
1004 for (object_size_type = 0; object_size_type <= 3; object_size_type++)
|
|
|
1005 {
|
|
|
1006 object_sizes[object_size_type] = XNEWVEC (unsigned HOST_WIDE_INT, num_ssa_names);
|
|
|
1007 computed[object_size_type] = BITMAP_ALLOC (NULL);
|
|
|
1008 }
|
|
|
1009
|
|
|
1010 init_offset_limit ();
|
|
|
1011 }
|
|
|
1012
|
|
|
1013
|
|
|
1014 /* Destroy data structures after the object size computation. */
|
|
|
1015
|
|
|
1016 void
|
|
|
1017 fini_object_sizes (void)
|
|
|
1018 {
|
|
|
1019 int object_size_type;
|
|
|
1020
|
|
|
1021 for (object_size_type = 0; object_size_type <= 3; object_size_type++)
|
|
|
1022 {
|
|
|
1023 free (object_sizes[object_size_type]);
|
|
|
1024 BITMAP_FREE (computed[object_size_type]);
|
|
|
1025 object_sizes[object_size_type] = NULL;
|
|
|
1026 }
|
|
|
1027 }
|
|
|
1028
|
|
|
1029
|
|
|
1030 /* Simple pass to optimize all __builtin_object_size () builtins. */
|
|
|
1031
|
|
|
1032 static unsigned int
|
|
|
1033 compute_object_sizes (void)
|
|
|
1034 {
|
|
|
1035 basic_block bb;
|
|
|
1036 FOR_EACH_BB (bb)
|
|
|
1037 {
|
|
|
1038 gimple_stmt_iterator i;
|
|
|
1039 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
|
|
|
1040 {
|
|
|
1041 tree callee, result;
|
|
|
1042 gimple call = gsi_stmt (i);
|
|
|
1043
|
|
|
1044 if (gimple_code (call) != GIMPLE_CALL)
|
|
|
1045 continue;
|
|
|
1046
|
|
|
1047 callee = gimple_call_fndecl (call);
|
|
|
1048 if (!callee
|
|
|
1049 || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
|
|
|
1050 || DECL_FUNCTION_CODE (callee) != BUILT_IN_OBJECT_SIZE)
|
|
|
1051 continue;
|
|
|
1052
|
|
|
1053 init_object_sizes ();
|
|
|
1054 result = fold_call_stmt (call, false);
|
|
|
1055 if (!result)
|
|
|
1056 {
|
|
|
1057 if (gimple_call_num_args (call) == 2
|
|
|
1058 && POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0))))
|
|
|
1059 {
|
|
|
1060 tree ost = gimple_call_arg (call, 1);
|
|
|
1061
|
|
|
1062 if (host_integerp (ost, 1))
|
|
|
1063 {
|
|
|
1064 unsigned HOST_WIDE_INT object_size_type
|
|
|
1065 = tree_low_cst (ost, 1);
|
|
|
1066
|
|
|
1067 if (object_size_type < 2)
|
|
|
1068 result = fold_convert (size_type_node,
|
|
|
1069 integer_minus_one_node);
|
|
|
1070 else if (object_size_type < 4)
|
|
|
1071 result = size_zero_node;
|
|
|
1072 }
|
|
|
1073 }
|
|
|
1074
|
|
|
1075 if (!result)
|
|
|
1076 continue;
|
|
|
1077 }
|
|
|
1078
|
|
|
1079 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
1080 {
|
|
|
1081 fprintf (dump_file, "Simplified\n ");
|
|
|
1082 print_gimple_stmt (dump_file, call, 0, dump_flags);
|
|
|
1083 }
|
|
|
1084
|
|
|
1085 if (!update_call_from_tree (&i, result))
|
|
|
1086 gcc_unreachable ();
|
|
|
1087
|
|
|
1088 /* NOTE: In the pre-tuples code, we called update_stmt here. This is
|
|
|
1089 now handled by gsi_replace, called from update_call_from_tree. */
|
|
|
1090
|
|
|
1091 if (dump_file && (dump_flags & TDF_DETAILS))
|
|
|
1092 {
|
|
|
1093 fprintf (dump_file, "to\n ");
|
|
|
1094 print_gimple_stmt (dump_file, call, 0, dump_flags);
|
|
|
1095 fprintf (dump_file, "\n");
|
|
|
1096 }
|
|
|
1097 }
|
|
|
1098 }
|
|
|
1099
|
|
|
1100 fini_object_sizes ();
|
|
|
1101 return 0;
|
|
|
1102 }
|
|
|
1103
|
|
|
1104 struct gimple_opt_pass pass_object_sizes =
|
|
|
1105 {
|
|
|
1106 {
|
|
|
1107 GIMPLE_PASS,
|
|
|
1108 "objsz", /* name */
|
|
|
1109 NULL, /* gate */
|
|
|
1110 compute_object_sizes, /* execute */
|
|
|
1111 NULL, /* sub */
|
|
|
1112 NULL, /* next */
|
|
|
1113 0, /* static_pass_number */
|
|
|
1114 0, /* tv_id */
|
|
|
1115 PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
|
|
|
1116 0, /* properties_provided */
|
|
|
1117 0, /* properties_destroyed */
|
|
|
1118 0, /* todo_flags_start */
|
|
|
1119 TODO_dump_func | TODO_verify_ssa /* todo_flags_finish */
|
|
|
1120 }
|
|
|
1121 };
|
