Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Octocat-spinner-32-eaf2f5

Cannot retrieve contributors at this time

file 280 lines (243 sloc) 7.843 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279
/* Callgraph construction.
Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
Free Software Foundation, Inc.
Contributed by Jan Hubicka

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "tree-flow.h"
#include "langhooks.h"
#include "pointer-set.h"
#include "cgraph.h"
#include "intl.h"
#include "gimple.h"
#include "tree-pass.h"

/* Walk tree and record all calls and references to functions/variables.
Called via walk_tree: TP is pointer to tree to be examined. */

static tree
record_reference (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
{
  tree t = *tp;
  tree decl;

  switch (TREE_CODE (t))
    {
    case VAR_DECL:
      if (TREE_STATIC (t) || DECL_EXTERNAL (t))
{
varpool_mark_needed_node (varpool_node (t));
if (lang_hooks.callgraph.analyze_expr)
return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees);
}
      break;

    case FDESC_EXPR:
    case ADDR_EXPR:
      /* Record dereferences to the functions. This makes the
functions reachable unconditionally. */
      decl = TREE_OPERAND (*tp, 0);
      if (TREE_CODE (decl) == FUNCTION_DECL)
cgraph_mark_needed_node (cgraph_node (decl));
      break;

    default:
      /* Save some cycles by not walking types and declaration as we
won't find anything useful there anyway. */
      if (IS_TYPE_OR_DECL_P (*tp))
{
*walk_subtrees = 0;
break;
}

      if ((unsigned int) TREE_CODE (t) >= LAST_AND_UNUSED_TREE_CODE)
return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees);
      break;
    }

  return NULL_TREE;
}

/* Give initial reasons why inlining would fail on all calls from
NODE. Those get either nullified or usually overwritten by more precise
reason later. */

static void
initialize_inline_failed (struct cgraph_node *node)
{
  struct cgraph_edge *e;

  for (e = node->callers; e; e = e->next_caller)
    {
      gcc_assert (!e->callee->global.inlined_to);
      gcc_assert (e->inline_failed);
      if (node->local.redefined_extern_inline)
e->inline_failed = N_("redefined extern inline functions are not "
"considered for inlining");
      else if (!node->local.inlinable)
e->inline_failed = N_("function not inlinable");
      else if (gimple_call_cannot_inline_p (e->call_stmt))
e->inline_failed = N_("mismatched arguments");
      else
e->inline_failed = N_("function not considered for inlining");
    }
}

/* Computes the frequency of the call statement so that it can be stored in
cgraph_edge. BB is the basic block of the call statement. */
int
compute_call_stmt_bb_frequency (basic_block bb)
{
  int entry_freq = ENTRY_BLOCK_PTR->frequency;
  int freq = bb->frequency;

  if (!entry_freq)
    entry_freq = 1, freq++;

  freq = freq * CGRAPH_FREQ_BASE / entry_freq;
  if (freq > CGRAPH_FREQ_MAX)
    freq = CGRAPH_FREQ_MAX;

  return freq;
}

/* Create cgraph edges for function calls.
Also look for functions and variables having addresses taken. */

static unsigned int
build_cgraph_edges (void)
{
  basic_block bb;
  struct cgraph_node *node = cgraph_node (current_function_decl);
  struct pointer_set_t *visited_nodes = pointer_set_create ();
  gimple_stmt_iterator gsi;
  tree step;

  /* Create the callgraph edges and record the nodes referenced by the function.
body. */
  FOR_EACH_BB (bb)
    for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
      {
gimple stmt = gsi_stmt (gsi);
tree decl;

if (is_gimple_call (stmt) && (decl = gimple_call_fndecl (stmt)))
{
size_t i;
size_t n = gimple_call_num_args (stmt);
cgraph_create_edge (node, cgraph_node (decl), stmt,
bb->count, compute_call_stmt_bb_frequency (bb),
bb->loop_depth);
for (i = 0; i < n; i++)
walk_tree (gimple_call_arg_ptr (stmt, i), record_reference,
node, visited_nodes);
if (gimple_call_lhs (stmt))
walk_tree (gimple_call_lhs_ptr (stmt), record_reference, node,
visited_nodes);
}
else
{
struct walk_stmt_info wi;
memset (&wi, 0, sizeof (wi));
wi.info = node;
wi.pset = visited_nodes;
walk_gimple_op (stmt, record_reference, &wi);
if (gimple_code (stmt) == GIMPLE_OMP_PARALLEL
&& gimple_omp_parallel_child_fn (stmt))
{
tree fn = gimple_omp_parallel_child_fn (stmt);
cgraph_mark_needed_node (cgraph_node (fn));
}
if (gimple_code (stmt) == GIMPLE_OMP_TASK)
{
tree fn = gimple_omp_task_child_fn (stmt);
if (fn)
cgraph_mark_needed_node (cgraph_node (fn));
fn = gimple_omp_task_copy_fn (stmt);
if (fn)
cgraph_mark_needed_node (cgraph_node (fn));
}
}
      }

  /* Look for initializers of constant variables and private statics. */
  for (step = cfun->local_decls;
       step;
       step = TREE_CHAIN (step))
    {
      tree decl = TREE_VALUE (step);
      if (TREE_CODE (decl) == VAR_DECL
&& (TREE_STATIC (decl) && !DECL_EXTERNAL (decl)))
varpool_finalize_decl (decl);
      else if (TREE_CODE (decl) == VAR_DECL && DECL_INITIAL (decl))
walk_tree (&DECL_INITIAL (decl), record_reference, node, visited_nodes);
    }

  pointer_set_destroy (visited_nodes);
  initialize_inline_failed (node);
  return 0;
}

struct gimple_opt_pass pass_build_cgraph_edges =
{
 {
  GIMPLE_PASS,
  NULL, /* name */
  NULL, /* gate */
  build_cgraph_edges, /* execute */
  NULL, /* sub */
  NULL, /* next */
  0, /* static_pass_number */
  0, /* tv_id */
  PROP_cfg, /* properties_required */
  0, /* properties_provided */
  0, /* properties_destroyed */
  0, /* todo_flags_start */
  0 /* todo_flags_finish */
 }
};

/* Record references to functions and other variables present in the
initial value of DECL, a variable. */

void
record_references_in_initializer (tree decl)
{
  struct pointer_set_t *visited_nodes = pointer_set_create ();
  walk_tree (&DECL_INITIAL (decl), record_reference, NULL, visited_nodes);
  pointer_set_destroy (visited_nodes);
}

/* Rebuild cgraph edges for current function node. This needs to be run after
passes that don't update the cgraph. */

unsigned int
rebuild_cgraph_edges (void)
{
  basic_block bb;
  struct cgraph_node *node = cgraph_node (current_function_decl);
  gimple_stmt_iterator gsi;

  cgraph_node_remove_callees (node);

  node->count = ENTRY_BLOCK_PTR->count;

  FOR_EACH_BB (bb)
    for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
      {
gimple stmt = gsi_stmt (gsi);
tree decl;

if (is_gimple_call (stmt) && (decl = gimple_call_fndecl (stmt)))
cgraph_create_edge (node, cgraph_node (decl), stmt,
bb->count, compute_call_stmt_bb_frequency (bb),
bb->loop_depth);

      }
  initialize_inline_failed (node);
  gcc_assert (!node->global.inlined_to);
  return 0;
}

struct gimple_opt_pass pass_rebuild_cgraph_edges =
{
 {
  GIMPLE_PASS,
  NULL, /* name */
  NULL, /* gate */
  rebuild_cgraph_edges, /* execute */
  NULL, /* sub */
  NULL, /* next */
  0, /* static_pass_number */
  0, /* tv_id */
  PROP_cfg, /* properties_required */
  0, /* properties_provided */
  0, /* properties_destroyed */
  0, /* todo_flags_start */
  0, /* todo_flags_finish */
 }
};
Something went wrong with that request. Please try again.