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111
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1 /* LTO symbol table.
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2 Copyright (C) 2009-2017 Free Software Foundation, Inc.
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3 Contributed by CodeSourcery, Inc.
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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 it under
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8 the terms of the GNU General Public License as published by the Free
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9 Software Foundation; either version 3, or (at your option) any later
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10 version.
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11
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12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
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14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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15 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 "target.h"
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25 #include "function.h"
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26 #include "basic-block.h"
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27 #include "tree.h"
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28 #include "gimple.h"
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29 #include "cgraph.h"
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30 #include "lto-streamer.h"
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31 #include "ipa-utils.h"
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32 #include "builtins.h"
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33 #include "alias.h"
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34 #include "lto-symtab.h"
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35 #include "stringpool.h"
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36 #include "attribs.h"
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37
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38 /* Replace the cgraph node NODE with PREVAILING_NODE in the cgraph, merging
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39 all edges and removing the old node. */
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40
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41 static void
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42 lto_cgraph_replace_node (struct cgraph_node *node,
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43 struct cgraph_node *prevailing_node)
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44 {
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45 struct cgraph_edge *e, *next;
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46 bool compatible_p;
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47
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48 if (symtab->dump_file)
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49 {
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50 fprintf (symtab->dump_file, "Replacing cgraph node %s by %s"
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51 " for symbol %s\n",
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52 node->dump_name (),
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53 prevailing_node->dump_name (),
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54 IDENTIFIER_POINTER ((*targetm.asm_out.mangle_assembler_name)
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55 (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (node->decl)))));
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56 }
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57
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58 /* Merge node flags. */
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59 if (node->force_output)
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60 prevailing_node->mark_force_output ();
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61 if (node->forced_by_abi)
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62 prevailing_node->forced_by_abi = true;
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63 if (node->address_taken)
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64 {
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65 gcc_assert (!prevailing_node->global.inlined_to);
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66 prevailing_node->mark_address_taken ();
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67 }
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68 if (node->definition && prevailing_node->definition
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69 && DECL_COMDAT (node->decl) && DECL_COMDAT (prevailing_node->decl))
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70 prevailing_node->merged_comdat = true;
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71
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72 /* Redirect all incoming edges. */
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73 compatible_p
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74 = types_compatible_p (TREE_TYPE (TREE_TYPE (prevailing_node->decl)),
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75 TREE_TYPE (TREE_TYPE (node->decl)));
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76 for (e = node->callers; e; e = next)
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77 {
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78 next = e->next_caller;
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79 e->redirect_callee (prevailing_node);
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80 /* If there is a mismatch between the supposed callee return type and
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81 the real one do not attempt to inline this function.
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82 ??? We really need a way to match function signatures for ABI
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83 compatibility and perform related promotions at inlining time. */
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84 if (!compatible_p)
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85 {
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86 e->inline_failed = CIF_LTO_MISMATCHED_DECLARATIONS;
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87 e->call_stmt_cannot_inline_p = 1;
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88 }
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89 }
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90 /* Redirect incomming references. */
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91 prevailing_node->clone_referring (node);
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92
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93 /* Fix instrumentation references. */
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94 if (node->instrumented_version)
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95 {
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96 gcc_assert (node->instrumentation_clone
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97 == prevailing_node->instrumentation_clone);
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98 node->instrumented_version->instrumented_version = prevailing_node;
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99 if (!prevailing_node->instrumented_version)
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100 prevailing_node->instrumented_version = node->instrumented_version;
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101 /* Need to reset node->instrumented_version to NULL,
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102 otherwise node removal code would reset
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103 node->instrumented_version->instrumented_version. */
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104 node->instrumented_version = NULL;
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105 }
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106
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107 lto_free_function_in_decl_state_for_node (node);
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108
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109 if (node->decl != prevailing_node->decl)
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110 node->release_body ();
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111
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112 /* Finally remove the replaced node. */
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113 node->remove ();
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114 }
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115
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116 /* Replace the cgraph node NODE with PREVAILING_NODE in the cgraph, merging
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117 all edges and removing the old node. */
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118
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119 static void
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120 lto_varpool_replace_node (varpool_node *vnode,
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121 varpool_node *prevailing_node)
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122 {
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123 gcc_assert (!vnode->definition || prevailing_node->definition);
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124 gcc_assert (!vnode->analyzed || prevailing_node->analyzed);
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125
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126 prevailing_node->clone_referring (vnode);
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127 if (vnode->force_output)
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128 prevailing_node->force_output = true;
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129 if (vnode->forced_by_abi)
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130 prevailing_node->forced_by_abi = true;
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131
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132 /* Be sure we can garbage collect the initializer. */
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133 if (DECL_INITIAL (vnode->decl)
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134 && vnode->decl != prevailing_node->decl)
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135 DECL_INITIAL (vnode->decl) = error_mark_node;
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136
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137 /* Check and report ODR violations on virtual tables. */
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138 if (DECL_VIRTUAL_P (vnode->decl) || DECL_VIRTUAL_P (prevailing_node->decl))
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139 compare_virtual_tables (prevailing_node, vnode);
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140
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141 if (vnode->tls_model != prevailing_node->tls_model)
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142 {
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143 bool error = false;
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144
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145 /* Non-TLS and TLS never mix together. Also emulated model is not
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146 compatible with anything else. */
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147 if (prevailing_node->tls_model == TLS_MODEL_NONE
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148 || prevailing_node->tls_model == TLS_MODEL_EMULATED
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149 || vnode->tls_model == TLS_MODEL_NONE
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150 || vnode->tls_model == TLS_MODEL_EMULATED)
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151 error = true;
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152 /* Linked is silently supporting transitions
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153 GD -> IE, GD -> LE, LD -> LE, IE -> LE, LD -> IE.
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154 Do the same transitions and error out on others. */
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155 else if ((prevailing_node->tls_model == TLS_MODEL_REAL
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156 || prevailing_node->tls_model == TLS_MODEL_LOCAL_DYNAMIC)
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157 && (vnode->tls_model == TLS_MODEL_INITIAL_EXEC
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158 || vnode->tls_model == TLS_MODEL_LOCAL_EXEC))
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159 prevailing_node->tls_model = vnode->tls_model;
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160 else if ((vnode->tls_model == TLS_MODEL_REAL
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161 || vnode->tls_model == TLS_MODEL_LOCAL_DYNAMIC)
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162 && (prevailing_node->tls_model == TLS_MODEL_INITIAL_EXEC
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163 || prevailing_node->tls_model == TLS_MODEL_LOCAL_EXEC))
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164 ;
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165 else if (prevailing_node->tls_model == TLS_MODEL_INITIAL_EXEC
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166 && vnode->tls_model == TLS_MODEL_LOCAL_EXEC)
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167 prevailing_node->tls_model = vnode->tls_model;
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168 else if (vnode->tls_model == TLS_MODEL_INITIAL_EXEC
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169 && prevailing_node->tls_model == TLS_MODEL_LOCAL_EXEC)
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170 ;
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171 else
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172 error = true;
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173 if (error)
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174 {
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175 error_at (DECL_SOURCE_LOCATION (vnode->decl),
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176 "%qD is defined with tls model %s", vnode->decl, tls_model_names [vnode->tls_model]);
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177 inform (DECL_SOURCE_LOCATION (prevailing_node->decl),
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178 "previously defined here as %s",
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179 tls_model_names [prevailing_node->tls_model]);
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180 }
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181 }
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182 /* Finally remove the replaced node. */
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183 vnode->remove ();
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184 }
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185
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186 /* Return non-zero if we want to output waring about T1 and T2.
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187 Return value is a bitmask of reasons of violation:
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188 Bit 0 indicates that types are not compatible.
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189 Bit 1 indicates that types are not compatible because of C++ ODR rule.
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190 If COMMON_OR_EXTERN is true, do not warn on size mismatches of arrays.
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191 Bit 2 indicates that types are not ODR compatible
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192
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193 The interoperability rules are language specific. At present we do only
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194 full checking for C++ ODR rule and for other languages we do basic check
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195 that data structures are of same size and TBAA compatible. Our TBAA
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196 implementation should be coarse enough so all valid type transitions
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197 across different languages are allowed.
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198
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199 In partiucular we thus allow almost arbitrary type changes with
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200 -fno-strict-aliasing which may be tough of as a feature rather than bug
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201 as it allows to implement dodgy tricks in the language runtimes.
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202
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203 Naturally this code can be strenghtened significantly if we could track
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204 down the language of origin. */
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205
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206 static int
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207 warn_type_compatibility_p (tree prevailing_type, tree type,
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208 bool common_or_extern)
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209 {
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210 int lev = 0;
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211 bool odr_p = odr_or_derived_type_p (prevailing_type)
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212 && odr_or_derived_type_p (type);
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213
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214 if (prevailing_type == type)
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215 return 0;
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216
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217 /* C++ provide a robust way to check for type compatibility via the ODR
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218 rule. */
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219 if (odr_p && !odr_types_equivalent_p (prevailing_type, type))
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220 lev |= 2;
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221
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222 /* Function types needs special care, because types_compatible_p never
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223 thinks prototype is compatible to non-prototype. */
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224 if (TREE_CODE (type) == FUNCTION_TYPE || TREE_CODE (type) == METHOD_TYPE)
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225 {
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226 if (TREE_CODE (type) != TREE_CODE (prevailing_type))
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227 lev |= 1;
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228 lev |= warn_type_compatibility_p (TREE_TYPE (prevailing_type),
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229 TREE_TYPE (type), false);
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230 if (TREE_CODE (type) == METHOD_TYPE
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231 && TREE_CODE (prevailing_type) == METHOD_TYPE)
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232 lev |= warn_type_compatibility_p (TYPE_METHOD_BASETYPE (prevailing_type),
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233 TYPE_METHOD_BASETYPE (type), false);
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234 if (prototype_p (prevailing_type) && prototype_p (type)
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235 && TYPE_ARG_TYPES (prevailing_type) != TYPE_ARG_TYPES (type))
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236 {
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237 tree parm1, parm2;
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238 for (parm1 = TYPE_ARG_TYPES (prevailing_type),
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239 parm2 = TYPE_ARG_TYPES (type);
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240 parm1 && parm2;
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241 parm1 = TREE_CHAIN (parm1),
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242 parm2 = TREE_CHAIN (parm2))
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243 lev |= warn_type_compatibility_p (TREE_VALUE (parm1),
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244 TREE_VALUE (parm2), false);
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245 if (parm1 || parm2)
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246 lev |= odr_p ? 3 : 1;
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247 }
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248 if (comp_type_attributes (prevailing_type, type) == 0)
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249 lev |= 1;
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250 return lev;
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251 }
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252
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253 /* Get complete type. */
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254 prevailing_type = TYPE_MAIN_VARIANT (prevailing_type);
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255 type = TYPE_MAIN_VARIANT (type);
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256
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257 /* We can not use types_compatible_p because we permit some changes
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258 across types. For example unsigned size_t and "signed size_t" may be
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259 compatible when merging C and Fortran types. */
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260 if (COMPLETE_TYPE_P (prevailing_type)
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261 && COMPLETE_TYPE_P (type)
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262 /* While global declarations are never variadic, we can recurse here
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263 for function parameter types. */
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264 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
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265 && TREE_CODE (TYPE_SIZE (prevailing_type)) == INTEGER_CST
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266 && !tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (prevailing_type)))
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267 {
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268 /* As a special case do not warn about merging
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269 int a[];
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270 and
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271 int a[]={1,2,3};
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272 here the first declaration is COMMON or EXTERN
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273 and sizeof(a) == sizeof (int). */
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274 if (!common_or_extern
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275 || TREE_CODE (type) != ARRAY_TYPE
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276 || TYPE_SIZE (type) != TYPE_SIZE (TREE_TYPE (type)))
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277 lev |= 1;
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278 }
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279
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280 /* Verify TBAA compatibility. Take care of alias set 0 and the fact that
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281 we make ptr_type_node to TBAA compatible with every other type. */
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282 if (type_with_alias_set_p (type) && type_with_alias_set_p (prevailing_type))
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283 {
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284 alias_set_type set1 = get_alias_set (type);
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285 alias_set_type set2 = get_alias_set (prevailing_type);
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286
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287 if (set1 && set2 && set1 != set2
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288 && (!POINTER_TYPE_P (type) || !POINTER_TYPE_P (prevailing_type)
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289 || (set1 != TYPE_ALIAS_SET (ptr_type_node)
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290 && set2 != TYPE_ALIAS_SET (ptr_type_node))))
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291 lev |= 5;
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292 }
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293
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294 return lev;
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295 }
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296
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297 /* Merge two variable or function symbol table entries PREVAILING and ENTRY.
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298 Return false if the symbols are not fully compatible and a diagnostic
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299 should be emitted. */
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300
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301 static bool
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302 lto_symtab_merge (symtab_node *prevailing, symtab_node *entry)
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303 {
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304 tree prevailing_decl = prevailing->decl;
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305 tree decl = entry->decl;
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306
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307 if (prevailing_decl == decl)
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308 return true;
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309
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310 if (TREE_CODE (decl) != TREE_CODE (prevailing_decl))
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311 return false;
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312
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313 /* Merge decl state in both directions, we may still end up using
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314 the new decl. */
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315 TREE_ADDRESSABLE (prevailing_decl) |= TREE_ADDRESSABLE (decl);
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316 TREE_ADDRESSABLE (decl) |= TREE_ADDRESSABLE (prevailing_decl);
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317
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318 /* The linker may ask us to combine two incompatible symbols.
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319 Detect this case and notify the caller of required diagnostics. */
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320
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321 if (TREE_CODE (decl) == FUNCTION_DECL)
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322 {
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323 /* Merge decl state in both directions, we may still end up using
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324 the new decl. */
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325 DECL_POSSIBLY_INLINED (prevailing_decl) |= DECL_POSSIBLY_INLINED (decl);
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326 DECL_POSSIBLY_INLINED (decl) |= DECL_POSSIBLY_INLINED (prevailing_decl);
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327
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328 if (warn_type_compatibility_p (TREE_TYPE (prevailing_decl),
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329 TREE_TYPE (decl),
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330 DECL_COMMON (decl)
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331 || DECL_EXTERNAL (decl)))
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332 return false;
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333
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334 return true;
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335 }
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336
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337 if (warn_type_compatibility_p (TREE_TYPE (prevailing_decl),
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338 TREE_TYPE (decl),
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339 DECL_COMMON (decl) || DECL_EXTERNAL (decl)))
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340 return false;
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341
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342 /* There is no point in comparing too many details of the decls here.
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343 The type compatibility checks or the completing of types has properly
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344 dealt with most issues. */
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345
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346 /* The following should all not invoke fatal errors as in non-LTO
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347 mode the linker wouldn't complain either. Just emit warnings. */
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348
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349 /* Report a warning if user-specified alignments do not match. */
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350 if ((DECL_USER_ALIGN (prevailing_decl) && DECL_USER_ALIGN (decl))
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351 && DECL_ALIGN (prevailing_decl) < DECL_ALIGN (decl))
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352 return false;
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353
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354 if (DECL_SIZE (decl) && DECL_SIZE (prevailing_decl)
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355 && !tree_int_cst_equal (DECL_SIZE (decl), DECL_SIZE (prevailing_decl))
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356 /* As a special case do not warn about merging
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357 int a[];
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358 and
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359 int a[]={1,2,3};
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360 here the first declaration is COMMON
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361 and sizeof(a) == sizeof (int). */
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362 && ((!DECL_COMMON (decl) && !DECL_EXTERNAL (decl))
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363 || TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE
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364 || TYPE_SIZE (TREE_TYPE (decl))
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365 != TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl)))))
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366 return false;
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367
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368 return true;
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369 }
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370
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371 /* Return true if the symtab entry E can be replaced by another symtab
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372 entry. */
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373
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374 static bool
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375 lto_symtab_resolve_replaceable_p (symtab_node *e)
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376 {
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377 if (DECL_EXTERNAL (e->decl)
|
|
|
378 || DECL_COMDAT (e->decl)
|
|
|
379 || DECL_ONE_ONLY (e->decl)
|
|
|
380 || DECL_WEAK (e->decl))
|
|
|
381 return true;
|
|
|
382
|
|
|
383 if (TREE_CODE (e->decl) == VAR_DECL)
|
|
|
384 return (DECL_COMMON (e->decl)
|
|
|
385 || (!flag_no_common && !DECL_INITIAL (e->decl)));
|
|
|
386
|
|
|
387 return false;
|
|
|
388 }
|
|
|
389
|
|
|
390 /* Return true, if the symbol E should be resolved by lto-symtab.
|
|
|
391 Those are all external symbols and all real symbols that are not static (we
|
|
|
392 handle renaming of static later in partitioning). */
|
|
|
393
|
|
|
394 static bool
|
|
|
395 lto_symtab_symbol_p (symtab_node *e)
|
|
|
396 {
|
|
|
397 if (!TREE_PUBLIC (e->decl) && !DECL_EXTERNAL (e->decl))
|
|
|
398 return false;
|
|
|
399 return e->real_symbol_p ();
|
|
|
400 }
|
|
|
401
|
|
|
402 /* Return true if the symtab entry E can be the prevailing one. */
|
|
|
403
|
|
|
404 static bool
|
|
|
405 lto_symtab_resolve_can_prevail_p (symtab_node *e)
|
|
|
406 {
|
|
|
407 if (!lto_symtab_symbol_p (e))
|
|
|
408 return false;
|
|
|
409
|
|
|
410 /* The C++ frontend ends up neither setting TREE_STATIC nor
|
|
|
411 DECL_EXTERNAL on virtual methods but only TREE_PUBLIC.
|
|
|
412 So do not reject !TREE_STATIC here but only DECL_EXTERNAL. */
|
|
|
413 if (DECL_EXTERNAL (e->decl))
|
|
|
414 return false;
|
|
|
415
|
|
|
416 return e->definition;
|
|
|
417 }
|
|
|
418
|
|
|
419 /* Resolve the symbol with the candidates in the chain *SLOT and store
|
|
|
420 their resolutions. */
|
|
|
421
|
|
|
422 static symtab_node *
|
|
|
423 lto_symtab_resolve_symbols (symtab_node *first)
|
|
|
424 {
|
|
|
425 symtab_node *e;
|
|
|
426 symtab_node *prevailing = NULL;
|
|
|
427
|
|
|
428 /* Always set e->node so that edges are updated to reflect decl merging. */
|
|
|
429 for (e = first; e; e = e->next_sharing_asm_name)
|
|
|
430 if (lto_symtab_symbol_p (e)
|
|
|
431 && (e->resolution == LDPR_PREVAILING_DEF_IRONLY
|
|
|
432 || e->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
|
|
|
433 || e->resolution == LDPR_PREVAILING_DEF))
|
|
|
434 {
|
|
|
435 prevailing = e;
|
|
|
436 break;
|
|
|
437 }
|
|
|
438
|
|
|
439 /* If the chain is already resolved there is nothing else to do. */
|
|
|
440 if (prevailing)
|
|
|
441 {
|
|
|
442 /* Assert it's the only one. */
|
|
|
443 for (e = prevailing->next_sharing_asm_name; e; e = e->next_sharing_asm_name)
|
|
|
444 if (lto_symtab_symbol_p (e)
|
|
|
445 && (e->resolution == LDPR_PREVAILING_DEF_IRONLY
|
|
|
446 || e->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
|
|
|
447 || e->resolution == LDPR_PREVAILING_DEF))
|
|
|
448 fatal_error (input_location, "multiple prevailing defs for %qE",
|
|
|
449 DECL_NAME (prevailing->decl));
|
|
|
450 return prevailing;
|
|
|
451 }
|
|
|
452
|
|
|
453 /* Find the single non-replaceable prevailing symbol and
|
|
|
454 diagnose ODR violations. */
|
|
|
455 for (e = first; e; e = e->next_sharing_asm_name)
|
|
|
456 {
|
|
|
457 if (!lto_symtab_resolve_can_prevail_p (e))
|
|
|
458 continue;
|
|
|
459
|
|
|
460 /* If we have a non-replaceable definition it prevails. */
|
|
|
461 if (!lto_symtab_resolve_replaceable_p (e))
|
|
|
462 {
|
|
|
463 if (prevailing)
|
|
|
464 {
|
|
|
465 error_at (DECL_SOURCE_LOCATION (e->decl),
|
|
|
466 "%qD has already been defined", e->decl);
|
|
|
467 inform (DECL_SOURCE_LOCATION (prevailing->decl),
|
|
|
468 "previously defined here");
|
|
|
469 }
|
|
|
470 prevailing = e;
|
|
|
471 }
|
|
|
472 }
|
|
|
473 if (prevailing)
|
|
|
474 return prevailing;
|
|
|
475
|
|
|
476 /* Do a second round choosing one from the replaceable prevailing decls. */
|
|
|
477 for (e = first; e; e = e->next_sharing_asm_name)
|
|
|
478 {
|
|
|
479 if (!lto_symtab_resolve_can_prevail_p (e))
|
|
|
480 continue;
|
|
|
481
|
|
|
482 /* Choose the first function that can prevail as prevailing. */
|
|
|
483 if (TREE_CODE (e->decl) == FUNCTION_DECL)
|
|
|
484 {
|
|
|
485 prevailing = e;
|
|
|
486 break;
|
|
|
487 }
|
|
|
488
|
|
|
489 /* From variables that can prevail choose the largest one. */
|
|
|
490 if (!prevailing
|
|
|
491 || tree_int_cst_lt (DECL_SIZE (prevailing->decl),
|
|
|
492 DECL_SIZE (e->decl))
|
|
|
493 /* When variables are equivalent try to chose one that has useful
|
|
|
494 DECL_INITIAL. This makes sense for keyed vtables that are
|
|
|
495 DECL_EXTERNAL but initialized. In units that do not need them
|
|
|
496 we replace the initializer by error_mark_node to conserve
|
|
|
497 memory.
|
|
|
498
|
|
|
499 We know that the vtable is keyed outside the LTO unit - otherwise
|
|
|
500 the keyed instance would prevail. We still can preserve useful
|
|
|
501 info in the initializer. */
|
|
|
502 || (DECL_SIZE (prevailing->decl) == DECL_SIZE (e->decl)
|
|
|
503 && (DECL_INITIAL (e->decl)
|
|
|
504 && DECL_INITIAL (e->decl) != error_mark_node)
|
|
|
505 && (!DECL_INITIAL (prevailing->decl)
|
|
|
506 || DECL_INITIAL (prevailing->decl) == error_mark_node)))
|
|
|
507 prevailing = e;
|
|
|
508 }
|
|
|
509
|
|
|
510 return prevailing;
|
|
|
511 }
|
|
|
512
|
|
|
513 /* Decide if it is OK to merge DECL into PREVAILING.
|
|
|
514 Because we wrap most of uses of declarations in MEM_REF, we can tolerate
|
|
|
515 some differences but other code may inspect directly the DECL. */
|
|
|
516
|
|
|
517 static bool
|
|
|
518 lto_symtab_merge_p (tree prevailing, tree decl)
|
|
|
519 {
|
|
|
520 if (TREE_CODE (prevailing) != TREE_CODE (decl))
|
|
|
521 {
|
|
|
522 if (symtab->dump_file)
|
|
|
523 fprintf (symtab->dump_file, "Not merging decls; "
|
|
|
524 "TREE_CODE mismatch\n");
|
|
|
525 return false;
|
|
|
526 }
|
|
|
527 gcc_checking_assert (TREE_CHAIN (prevailing) == TREE_CHAIN (decl));
|
|
|
528
|
|
|
529 if (TREE_CODE (prevailing) == FUNCTION_DECL)
|
|
|
530 {
|
|
|
531 if (DECL_BUILT_IN (prevailing) != DECL_BUILT_IN (decl))
|
|
|
532 {
|
|
|
533 if (symtab->dump_file)
|
|
|
534 fprintf (symtab->dump_file, "Not merging decls; "
|
|
|
535 "DECL_BUILT_IN mismatch\n");
|
|
|
536 return false;
|
|
|
537 }
|
|
|
538 if (DECL_BUILT_IN (prevailing)
|
|
|
539 && (DECL_BUILT_IN_CLASS (prevailing) != DECL_BUILT_IN_CLASS (decl)
|
|
|
540 || DECL_FUNCTION_CODE (prevailing) != DECL_FUNCTION_CODE (decl)))
|
|
|
541 {
|
|
|
542 if (symtab->dump_file)
|
|
|
543 fprintf (symtab->dump_file, "Not merging decls; "
|
|
|
544 "DECL_BUILT_IN_CLASS or CODE mismatch\n");
|
|
|
545 return false;
|
|
|
546 }
|
|
|
547 }
|
|
|
548 if (DECL_ATTRIBUTES (prevailing) != DECL_ATTRIBUTES (decl))
|
|
|
549 {
|
|
|
550 tree prev_attr = lookup_attribute ("error", DECL_ATTRIBUTES (prevailing));
|
|
|
551 tree attr = lookup_attribute ("error", DECL_ATTRIBUTES (decl));
|
|
|
552 if ((prev_attr == NULL) != (attr == NULL)
|
|
|
553 || (prev_attr
|
|
|
554 && TREE_VALUE (TREE_VALUE (prev_attr))
|
|
|
555 != TREE_VALUE (TREE_VALUE (attr))))
|
|
|
556 {
|
|
|
557 if (symtab->dump_file)
|
|
|
558 fprintf (symtab->dump_file, "Not merging decls; "
|
|
|
559 "error attribute mismatch\n");
|
|
|
560 return false;
|
|
|
561 }
|
|
|
562
|
|
|
563 prev_attr = lookup_attribute ("warning", DECL_ATTRIBUTES (prevailing));
|
|
|
564 attr = lookup_attribute ("warning", DECL_ATTRIBUTES (decl));
|
|
|
565 if ((prev_attr == NULL) != (attr == NULL)
|
|
|
566 || (prev_attr
|
|
|
567 && TREE_VALUE (TREE_VALUE (prev_attr))
|
|
|
568 != TREE_VALUE (TREE_VALUE (attr))))
|
|
|
569 {
|
|
|
570 if (symtab->dump_file)
|
|
|
571 fprintf (symtab->dump_file, "Not merging decls; "
|
|
|
572 "warning attribute mismatch\n");
|
|
|
573 return false;
|
|
|
574 }
|
|
|
575 }
|
|
|
576 return true;
|
|
|
577 }
|
|
|
578
|
|
|
579 /* Merge all decls in the symbol table chain to the prevailing decl and
|
|
|
580 issue diagnostics about type mismatches. If DIAGNOSED_P is true
|
|
|
581 do not issue further diagnostics.*/
|
|
|
582
|
|
|
583 static void
|
|
|
584 lto_symtab_merge_decls_2 (symtab_node *first, bool diagnosed_p)
|
|
|
585 {
|
|
|
586 symtab_node *prevailing;
|
|
|
587 symtab_node *e;
|
|
|
588 vec<tree> mismatches = vNULL;
|
|
|
589 unsigned i;
|
|
|
590 tree decl;
|
|
|
591 bool tbaa_p = false;
|
|
|
592
|
|
|
593 /* Nothing to do for a single entry. */
|
|
|
594 prevailing = first;
|
|
|
595 if (!prevailing->next_sharing_asm_name)
|
|
|
596 return;
|
|
|
597
|
|
|
598 /* Try to merge each entry with the prevailing one. */
|
|
|
599 symtab_node *last_prevailing = prevailing, *next;
|
|
|
600 for (e = prevailing->next_sharing_asm_name; e; e = next)
|
|
|
601 {
|
|
|
602 next = e->next_sharing_asm_name;
|
|
|
603
|
|
|
604 /* Skip non-LTO symbols and symbols whose declaration we already
|
|
|
605 visited. */
|
|
|
606 if (lto_symtab_prevailing_decl (e->decl) != e->decl
|
|
|
607 || !lto_symtab_symbol_p (e)
|
|
|
608 || e->decl == prevailing->decl)
|
|
|
609 continue;
|
|
|
610
|
|
|
611 if (!lto_symtab_merge (prevailing, e)
|
|
|
612 && !diagnosed_p
|
|
|
613 && !DECL_ARTIFICIAL (e->decl))
|
|
|
614 mismatches.safe_push (e->decl);
|
|
|
615
|
|
|
616 symtab_node *this_prevailing;
|
|
|
617 for (this_prevailing = prevailing; ;
|
|
|
618 this_prevailing = this_prevailing->next_sharing_asm_name)
|
|
|
619 {
|
|
|
620 if (this_prevailing->decl != e->decl
|
|
|
621 && lto_symtab_merge_p (this_prevailing->decl, e->decl))
|
|
|
622 break;
|
|
|
623 if (this_prevailing == last_prevailing)
|
|
|
624 {
|
|
|
625 this_prevailing = NULL;
|
|
|
626 break;
|
|
|
627 }
|
|
|
628 }
|
|
|
629
|
|
|
630 if (this_prevailing)
|
|
|
631 lto_symtab_prevail_decl (this_prevailing->decl, e->decl);
|
|
|
632 /* Maintain LRU list: relink the new prevaililng symbol
|
|
|
633 just after previaling node in the chain and update last_prevailing.
|
|
|
634 Since the number of possible declarations of a given symbol is
|
|
|
635 small, this should be faster than building a hash. */
|
|
|
636 else if (e == prevailing->next_sharing_asm_name)
|
|
|
637 last_prevailing = e;
|
|
|
638 else
|
|
|
639 {
|
|
|
640 if (e->next_sharing_asm_name)
|
|
|
641 e->next_sharing_asm_name->previous_sharing_asm_name
|
|
|
642 = e->previous_sharing_asm_name;
|
|
|
643 e->previous_sharing_asm_name->next_sharing_asm_name
|
|
|
644 = e->next_sharing_asm_name;
|
|
|
645 e->previous_sharing_asm_name = prevailing;
|
|
|
646 e->next_sharing_asm_name = prevailing->next_sharing_asm_name;
|
|
|
647 prevailing->next_sharing_asm_name->previous_sharing_asm_name = e;
|
|
|
648 prevailing->next_sharing_asm_name = e;
|
|
|
649 if (last_prevailing == prevailing)
|
|
|
650 last_prevailing = e;
|
|
|
651 }
|
|
|
652 }
|
|
|
653 if (mismatches.is_empty ())
|
|
|
654 return;
|
|
|
655
|
|
|
656 /* Diagnose all mismatched re-declarations. */
|
|
|
657 FOR_EACH_VEC_ELT (mismatches, i, decl)
|
|
|
658 {
|
|
|
659 /* Do not diagnose two built-in declarations, there is no useful
|
|
|
660 location in that case. It also happens for AVR if two built-ins
|
|
|
661 use the same asm name because their libgcc assembler code is the
|
|
|
662 same, see PR78562. */
|
|
|
663 if (DECL_IS_BUILTIN (prevailing->decl)
|
|
|
664 && DECL_IS_BUILTIN (decl))
|
|
|
665 continue;
|
|
|
666
|
|
|
667 int level = warn_type_compatibility_p (TREE_TYPE (prevailing->decl),
|
|
|
668 TREE_TYPE (decl),
|
|
|
669 DECL_COMDAT (decl));
|
|
|
670 if (level)
|
|
|
671 {
|
|
|
672 bool diag = false;
|
|
|
673 if (level & 2)
|
|
|
674 diag = warning_at (DECL_SOURCE_LOCATION (decl),
|
|
|
675 OPT_Wodr,
|
|
|
676 "%qD violates the C++ One Definition Rule ",
|
|
|
677 decl);
|
|
|
678 if (!diag && (level & 1))
|
|
|
679 diag = warning_at (DECL_SOURCE_LOCATION (decl),
|
|
|
680 OPT_Wlto_type_mismatch,
|
|
|
681 "type of %qD does not match original "
|
|
|
682 "declaration", decl);
|
|
|
683 if (diag)
|
|
|
684 {
|
|
|
685 warn_types_mismatch (TREE_TYPE (prevailing->decl),
|
|
|
686 TREE_TYPE (decl),
|
|
|
687 DECL_SOURCE_LOCATION (prevailing->decl),
|
|
|
688 DECL_SOURCE_LOCATION (decl));
|
|
|
689 if ((level & 4)
|
|
|
690 && !TREE_READONLY (prevailing->decl))
|
|
|
691 tbaa_p = true;
|
|
|
692 }
|
|
|
693 diagnosed_p |= diag;
|
|
|
694 }
|
|
|
695 else if ((DECL_USER_ALIGN (prevailing->decl)
|
|
|
696 && DECL_USER_ALIGN (decl))
|
|
|
697 && DECL_ALIGN (prevailing->decl) < DECL_ALIGN (decl))
|
|
|
698 {
|
|
|
699 diagnosed_p |= warning_at (DECL_SOURCE_LOCATION (decl),
|
|
|
700 OPT_Wlto_type_mismatch,
|
|
|
701 "alignment of %qD is bigger than "
|
|
|
702 "original declaration", decl);
|
|
|
703 }
|
|
|
704 else
|
|
|
705 diagnosed_p |= warning_at (DECL_SOURCE_LOCATION (decl),
|
|
|
706 OPT_Wlto_type_mismatch,
|
|
|
707 "size of %qD differ from the size of "
|
|
|
708 "original declaration", decl);
|
|
|
709 }
|
|
|
710 if (diagnosed_p)
|
|
|
711 inform (DECL_SOURCE_LOCATION (prevailing->decl),
|
|
|
712 "%qD was previously declared here", prevailing->decl);
|
|
|
713 if (tbaa_p)
|
|
|
714 inform (DECL_SOURCE_LOCATION (prevailing->decl),
|
|
|
715 "code may be misoptimized unless "
|
|
|
716 "-fno-strict-aliasing is used");
|
|
|
717
|
|
|
718 mismatches.release ();
|
|
|
719 }
|
|
|
720
|
|
|
721 /* Helper to process the decl chain for the symbol table entry *SLOT. */
|
|
|
722
|
|
|
723 static void
|
|
|
724 lto_symtab_merge_decls_1 (symtab_node *first)
|
|
|
725 {
|
|
|
726 symtab_node *e;
|
|
|
727 symtab_node *prevailing;
|
|
|
728 bool diagnosed_p = false;
|
|
|
729
|
|
|
730 if (symtab->dump_file)
|
|
|
731 {
|
|
|
732 fprintf (symtab->dump_file, "Merging nodes for %s. Candidates:\n",
|
|
|
733 first->asm_name ());
|
|
|
734 for (e = first; e; e = e->next_sharing_asm_name)
|
|
|
735 if (TREE_PUBLIC (e->decl))
|
|
|
736 e->dump (symtab->dump_file);
|
|
|
737 }
|
|
|
738
|
|
|
739 /* Compute the symbol resolutions. This is a no-op when using the
|
|
|
740 linker plugin and resolution was decided by the linker. */
|
|
|
741 prevailing = lto_symtab_resolve_symbols (first);
|
|
|
742
|
|
|
743 /* If there's not a prevailing symbol yet it's an external reference.
|
|
|
744 Happens a lot during ltrans. Choose the first symbol with a
|
|
|
745 cgraph or a varpool node. */
|
|
|
746 if (!prevailing)
|
|
|
747 {
|
|
|
748 for (prevailing = first;
|
|
|
749 prevailing; prevailing = prevailing->next_sharing_asm_name)
|
|
|
750 if (lto_symtab_symbol_p (prevailing))
|
|
|
751 break;
|
|
|
752 if (!prevailing)
|
|
|
753 return;
|
|
|
754 /* For variables chose with a priority variant with vnode
|
|
|
755 attached (i.e. from unit where external declaration of
|
|
|
756 variable is actually used).
|
|
|
757 When there are multiple variants, chose one with size.
|
|
|
758 This is needed for C++ typeinfos, for example in
|
|
|
759 lto/20081204-1 there are typeifos in both units, just
|
|
|
760 one of them do have size. */
|
|
|
761 if (TREE_CODE (prevailing->decl) == VAR_DECL)
|
|
|
762 {
|
|
|
763 for (e = prevailing->next_sharing_asm_name;
|
|
|
764 e; e = e->next_sharing_asm_name)
|
|
|
765 if (!COMPLETE_TYPE_P (TREE_TYPE (prevailing->decl))
|
|
|
766 && COMPLETE_TYPE_P (TREE_TYPE (e->decl))
|
|
|
767 && lto_symtab_symbol_p (e))
|
|
|
768 prevailing = e;
|
|
|
769 }
|
|
|
770 /* For functions prefer the non-builtin if one is available. */
|
|
|
771 else if (TREE_CODE (prevailing->decl) == FUNCTION_DECL)
|
|
|
772 {
|
|
|
773 for (e = first; e; e = e->next_sharing_asm_name)
|
|
|
774 if (TREE_CODE (e->decl) == FUNCTION_DECL
|
|
|
775 && !DECL_BUILT_IN (e->decl)
|
|
|
776 && lto_symtab_symbol_p (e))
|
|
|
777 {
|
|
|
778 prevailing = e;
|
|
|
779 break;
|
|
|
780 }
|
|
|
781 }
|
|
|
782 }
|
|
|
783
|
|
|
784 symtab->symtab_prevail_in_asm_name_hash (prevailing);
|
|
|
785
|
|
|
786 /* Diagnose mismatched objects. */
|
|
|
787 for (e = prevailing->next_sharing_asm_name;
|
|
|
788 e; e = e->next_sharing_asm_name)
|
|
|
789 {
|
|
|
790 if (TREE_CODE (prevailing->decl)
|
|
|
791 == TREE_CODE (e->decl))
|
|
|
792 continue;
|
|
|
793 if (!lto_symtab_symbol_p (e))
|
|
|
794 continue;
|
|
|
795
|
|
|
796 switch (TREE_CODE (prevailing->decl))
|
|
|
797 {
|
|
|
798 case VAR_DECL:
|
|
|
799 gcc_assert (TREE_CODE (e->decl) == FUNCTION_DECL);
|
|
|
800 error_at (DECL_SOURCE_LOCATION (e->decl),
|
|
|
801 "variable %qD redeclared as function",
|
|
|
802 prevailing->decl);
|
|
|
803 break;
|
|
|
804
|
|
|
805 case FUNCTION_DECL:
|
|
|
806 gcc_assert (TREE_CODE (e->decl) == VAR_DECL);
|
|
|
807 error_at (DECL_SOURCE_LOCATION (e->decl),
|
|
|
808 "function %qD redeclared as variable",
|
|
|
809 prevailing->decl);
|
|
|
810 break;
|
|
|
811
|
|
|
812 default:
|
|
|
813 gcc_unreachable ();
|
|
|
814 }
|
|
|
815
|
|
|
816 diagnosed_p = true;
|
|
|
817 }
|
|
|
818 if (diagnosed_p)
|
|
|
819 inform (DECL_SOURCE_LOCATION (prevailing->decl),
|
|
|
820 "previously declared here");
|
|
|
821
|
|
|
822 /* Merge the chain to the single prevailing decl and diagnose
|
|
|
823 mismatches. */
|
|
|
824 lto_symtab_merge_decls_2 (prevailing, diagnosed_p);
|
|
|
825
|
|
|
826 if (symtab->dump_file)
|
|
|
827 {
|
|
|
828 fprintf (symtab->dump_file, "After resolution:\n");
|
|
|
829 for (e = prevailing; e; e = e->next_sharing_asm_name)
|
|
|
830 e->dump (symtab->dump_file);
|
|
|
831 }
|
|
|
832 }
|
|
|
833
|
|
|
834 /* Resolve and merge all symbol table chains to a prevailing decl. */
|
|
|
835
|
|
|
836 void
|
|
|
837 lto_symtab_merge_decls (void)
|
|
|
838 {
|
|
|
839 symtab_node *node;
|
|
|
840
|
|
|
841 /* Populate assembler name hash. */
|
|
|
842 symtab->symtab_initialize_asm_name_hash ();
|
|
|
843
|
|
|
844 FOR_EACH_SYMBOL (node)
|
|
|
845 if (!node->previous_sharing_asm_name
|
|
|
846 && node->next_sharing_asm_name)
|
|
|
847 lto_symtab_merge_decls_1 (node);
|
|
|
848 }
|
|
|
849
|
|
|
850 /* Helper to process the decl chain for the symbol table entry *SLOT. */
|
|
|
851
|
|
|
852 static void
|
|
|
853 lto_symtab_merge_symbols_1 (symtab_node *prevailing)
|
|
|
854 {
|
|
|
855 symtab_node *e;
|
|
|
856 symtab_node *next;
|
|
|
857
|
|
|
858 prevailing->decl->decl_with_vis.symtab_node = prevailing;
|
|
|
859
|
|
|
860 /* Replace the cgraph node of each entry with the prevailing one. */
|
|
|
861 for (e = prevailing->next_sharing_asm_name; e;
|
|
|
862 e = next)
|
|
|
863 {
|
|
|
864 next = e->next_sharing_asm_name;
|
|
|
865
|
|
|
866 if (!lto_symtab_symbol_p (e))
|
|
|
867 continue;
|
|
|
868 cgraph_node *ce = dyn_cast <cgraph_node *> (e);
|
|
|
869 symtab_node *to = symtab_node::get (lto_symtab_prevailing_decl (e->decl));
|
|
|
870
|
|
|
871 /* No matter how we are going to deal with resolution, we will ultimately
|
|
|
872 use prevailing definition. */
|
|
|
873 if (ce)
|
|
|
874 ipa_merge_profiles (dyn_cast<cgraph_node *> (prevailing),
|
|
|
875 dyn_cast<cgraph_node *> (e));
|
|
|
876
|
|
|
877 /* If we decided to replace the node by TO, do it. */
|
|
|
878 if (e != to)
|
|
|
879 {
|
|
|
880 if (ce)
|
|
|
881 lto_cgraph_replace_node (ce, dyn_cast<cgraph_node *> (to));
|
|
|
882 else if (varpool_node *ve = dyn_cast <varpool_node *> (e))
|
|
|
883 lto_varpool_replace_node (ve, dyn_cast<varpool_node *> (to));
|
|
|
884 }
|
|
|
885 /* Watch out for duplicated symbols for a given declaration. */
|
|
|
886 else if (!e->transparent_alias
|
|
|
887 || !e->definition || e->get_alias_target () != to)
|
|
|
888 {
|
|
|
889 /* We got a new declaration we do not want to merge. In this case
|
|
|
890 get rid of the existing definition and create a transparent
|
|
|
891 alias. */
|
|
|
892 if (ce)
|
|
|
893 {
|
|
|
894 lto_free_function_in_decl_state_for_node (ce);
|
|
|
895 if (!ce->weakref)
|
|
|
896 ce->release_body ();
|
|
|
897 ce->reset ();
|
|
|
898 symtab->call_cgraph_removal_hooks (ce);
|
|
|
899 }
|
|
|
900 else
|
|
|
901 {
|
|
|
902 DECL_INITIAL (e->decl) = error_mark_node;
|
|
|
903 if (e->lto_file_data)
|
|
|
904 {
|
|
|
905 lto_free_function_in_decl_state_for_node (e);
|
|
|
906 e->lto_file_data = NULL;
|
|
|
907 }
|
|
|
908 symtab->call_varpool_removal_hooks (dyn_cast<varpool_node *> (e));
|
|
|
909 }
|
|
|
910 e->remove_all_references ();
|
|
|
911 e->analyzed = e->body_removed = false;
|
|
|
912 e->resolve_alias (prevailing, true);
|
|
|
913 gcc_assert (e != prevailing);
|
|
|
914 }
|
|
|
915 }
|
|
|
916
|
|
|
917 return;
|
|
|
918 }
|
|
|
919
|
|
|
920 /* Merge cgraph nodes according to the symbol merging done by
|
|
|
921 lto_symtab_merge_decls. */
|
|
|
922
|
|
|
923 void
|
|
|
924 lto_symtab_merge_symbols (void)
|
|
|
925 {
|
|
|
926 symtab_node *node;
|
|
|
927
|
|
|
928 if (!flag_ltrans)
|
|
|
929 {
|
|
|
930 symtab->symtab_initialize_asm_name_hash ();
|
|
|
931
|
|
|
932 /* Do the actual merging.
|
|
|
933 At this point we invalidate hash translating decls into symtab nodes
|
|
|
934 because after removing one of duplicate decls the hash is not correcly
|
|
|
935 updated to the ohter dupliate. */
|
|
|
936 FOR_EACH_SYMBOL (node)
|
|
|
937 if (lto_symtab_symbol_p (node)
|
|
|
938 && node->next_sharing_asm_name
|
|
|
939 && !node->previous_sharing_asm_name)
|
|
|
940 lto_symtab_merge_symbols_1 (node);
|
|
|
941
|
|
|
942 /* Resolve weakref aliases whose target are now in the compilation unit.
|
|
|
943 also re-populate the hash translating decls into symtab nodes*/
|
|
|
944 FOR_EACH_SYMBOL (node)
|
|
|
945 {
|
|
|
946 cgraph_node *cnode, *cnode2;
|
|
|
947 varpool_node *vnode;
|
|
|
948 symtab_node *node2;
|
|
|
949
|
|
|
950 if (!node->analyzed && node->alias_target)
|
|
|
951 {
|
|
|
952 symtab_node *tgt = symtab_node::get_for_asmname (node->alias_target);
|
|
|
953 gcc_assert (node->weakref);
|
|
|
954 if (tgt)
|
|
|
955 node->resolve_alias (tgt, true);
|
|
|
956 }
|
|
|
957 /* If the symbol was preempted outside IR, see if we want to get rid
|
|
|
958 of the definition. */
|
|
|
959 if (node->analyzed
|
|
|
960 && !DECL_EXTERNAL (node->decl)
|
|
|
961 && (node->resolution == LDPR_PREEMPTED_REG
|
|
|
962 || node->resolution == LDPR_RESOLVED_IR
|
|
|
963 || node->resolution == LDPR_RESOLVED_EXEC
|
|
|
964 || node->resolution == LDPR_RESOLVED_DYN))
|
|
|
965 {
|
|
|
966 DECL_EXTERNAL (node->decl) = 1;
|
|
|
967 /* If alias to local symbol was preempted by external definition,
|
|
|
968 we know it is not pointing to the local symbol. Remove it. */
|
|
|
969 if (node->alias
|
|
|
970 && !node->weakref
|
|
|
971 && !node->transparent_alias
|
|
|
972 && node->get_alias_target ()->binds_to_current_def_p ())
|
|
|
973 {
|
|
|
974 node->alias = false;
|
|
|
975 node->remove_all_references ();
|
|
|
976 node->definition = false;
|
|
|
977 node->analyzed = false;
|
|
|
978 node->cpp_implicit_alias = false;
|
|
|
979 }
|
|
|
980 else if (!node->alias
|
|
|
981 && node->definition
|
|
|
982 && node->get_availability () <= AVAIL_INTERPOSABLE)
|
|
|
983 {
|
|
|
984 if ((cnode = dyn_cast <cgraph_node *> (node)) != NULL)
|
|
|
985 cnode->reset ();
|
|
|
986 else
|
|
|
987 {
|
|
|
988 node->analyzed = node->definition = false;
|
|
|
989 node->remove_all_references ();
|
|
|
990 }
|
|
|
991 }
|
|
|
992 }
|
|
|
993
|
|
|
994 if (!(cnode = dyn_cast <cgraph_node *> (node))
|
|
|
995 || !cnode->clone_of
|
|
|
996 || cnode->clone_of->decl != cnode->decl)
|
|
|
997 {
|
|
|
998 /* Builtins are not merged via decl merging. It is however
|
|
|
999 possible that tree merging unified the declaration. We
|
|
|
1000 do not want duplicate entries in symbol table. */
|
|
|
1001 if (cnode && DECL_BUILT_IN (node->decl)
|
|
|
1002 && (cnode2 = cgraph_node::get (node->decl))
|
|
|
1003 && cnode2 != cnode)
|
|
|
1004 lto_cgraph_replace_node (cnode2, cnode);
|
|
|
1005
|
|
|
1006 /* The user defined assembler variables are also not unified by their
|
|
|
1007 symbol name (since it is irrelevant), but we need to unify symbol
|
|
|
1008 nodes if tree merging occurred. */
|
|
|
1009 if ((vnode = dyn_cast <varpool_node *> (node))
|
|
|
1010 && DECL_HARD_REGISTER (vnode->decl)
|
|
|
1011 && (node2 = symtab_node::get (vnode->decl))
|
|
|
1012 && node2 != node)
|
|
|
1013 lto_varpool_replace_node (dyn_cast <varpool_node *> (node2),
|
|
|
1014 vnode);
|
|
|
1015
|
|
|
1016
|
|
|
1017 /* Abstract functions may have duplicated cgraph nodes attached;
|
|
|
1018 remove them. */
|
|
|
1019 else if (cnode && DECL_ABSTRACT_P (cnode->decl)
|
|
|
1020 && (cnode2 = cgraph_node::get (node->decl))
|
|
|
1021 && cnode2 != cnode)
|
|
|
1022 cnode2->remove ();
|
|
|
1023
|
|
|
1024 node->decl->decl_with_vis.symtab_node = node;
|
|
|
1025 }
|
|
|
1026 }
|
|
|
1027 }
|
|
|
1028 }
|
|
|
1029
|
|
|
1030 /* Virtual tables may matter for code generation even if they are not
|
|
|
1031 directly refernced by the code because they may be used for devirtualizaiton.
|
|
|
1032 For this reason it is important to merge even virtual tables that have no
|
|
|
1033 associated symbol table entries. Without doing so we lose optimization
|
|
|
1034 oppurtunities by losing track of the vtable constructor.
|
|
|
1035 FIXME: we probably ought to introduce explicit symbol table entries for
|
|
|
1036 those before streaming. */
|
|
|
1037
|
|
|
1038 tree
|
|
|
1039 lto_symtab_prevailing_virtual_decl (tree decl)
|
|
|
1040 {
|
|
|
1041 if (DECL_ABSTRACT_P (decl))
|
|
|
1042 return decl;
|
|
|
1043 gcc_checking_assert (!type_in_anonymous_namespace_p (DECL_CONTEXT (decl))
|
|
|
1044 && DECL_ASSEMBLER_NAME_SET_P (decl));
|
|
|
1045
|
|
|
1046 symtab_node *n = symtab_node::get_for_asmname
|
|
|
1047 (DECL_ASSEMBLER_NAME (decl));
|
|
|
1048 while (n && ((!DECL_EXTERNAL (n->decl) && !TREE_PUBLIC (n->decl))
|
|
|
1049 || !DECL_VIRTUAL_P (n->decl)))
|
|
|
1050 n = n->next_sharing_asm_name;
|
|
|
1051 if (n)
|
|
|
1052 {
|
|
|
1053 /* Merge decl state in both directions, we may still end up using
|
|
|
1054 the other decl. */
|
|
|
1055 TREE_ADDRESSABLE (n->decl) |= TREE_ADDRESSABLE (decl);
|
|
|
1056 TREE_ADDRESSABLE (decl) |= TREE_ADDRESSABLE (n->decl);
|
|
|
1057
|
|
|
1058 if (TREE_CODE (decl) == FUNCTION_DECL)
|
|
|
1059 {
|
|
|
1060 /* Merge decl state in both directions, we may still end up using
|
|
|
1061 the other decl. */
|
|
|
1062 DECL_POSSIBLY_INLINED (n->decl) |= DECL_POSSIBLY_INLINED (decl);
|
|
|
1063 DECL_POSSIBLY_INLINED (decl) |= DECL_POSSIBLY_INLINED (n->decl);
|
|
|
1064 }
|
|
|
1065 lto_symtab_prevail_decl (n->decl, decl);
|
|
|
1066 decl = n->decl;
|
|
|
1067 }
|
|
|
1068 else
|
|
|
1069 symtab_node::get_create (decl);
|
|
|
1070
|
|
|
1071 return decl;
|
|
|
1072 }
|
