C++ DECL_STRUCT_FUNCTION函数代码示例

int getSize(char *name) {
	struct cgraph_node *node;
	basic_block bb;
	gimple statement;
	enum gimple_code code;
	gimple_stmt_iterator gsi;

	int size = 0;
	for (node = cgraph_nodes; node; node = node->next) {
		/* Nodes without a body, and clone nodes are not interesting. */
		if (!gimple_has_body_p(node->decl) || node->clone_of)
			continue;

		if (strcmp(cgraph_node_name(node), name) == 0) {
			set_cfun(DECL_STRUCT_FUNCTION(node->decl));
			//fprintf(stderr, "%s  -->  ", cgraph_node_name(node));
			FOR_ALL_BB(bb) {
				for (gsi = gsi_start_bb(bb); !gsi_end_p(gsi); gsi_next(&gsi)) {
					statement = gsi_stmt(gsi);
					code = gimple_code(statement);
					//debug_gimple_stmt(statement);
					if (code != GIMPLE_CALL) {
						size++;
					}
				}
			}

			return size;
		}
	}

static void
test_conversion_to_ssa ()
{
  /* As above, construct a trivial function, gimplify it, and build a CFG: */
  tree fndecl = build_trivial_high_gimple_function ();
  function *fun = DECL_STRUCT_FUNCTION (fndecl);
  ASSERT_TRUE (fun != NULL);
  build_cfg (fndecl);

  convert_to_ssa (fndecl);

  verify_three_block_gimple_cfg (fun);

  /* For out trivial test function we should now have something like
     this:
       test_fn ()
       {
	 <bb 2>:
	 _1 = 42;
	 return _1;
       }
  */
  basic_block bb2 = get_real_block (fun);
  gimple *stmt_a = gimple_seq_first_stmt (bb_seq (bb2));
  ASSERT_EQ (GIMPLE_ASSIGN, gimple_code (stmt_a));

  gimple *stmt_b = stmt_a->next;
  ASSERT_EQ (GIMPLE_RETURN, gimple_code (stmt_b));
  ASSERT_EQ (NULL, stmt_b->next);

  greturn *return_stmt = as_a <greturn *> (stmt_b);
  ASSERT_EQ (SSA_NAME, TREE_CODE (gimple_return_retval (return_stmt)));
}

void
record_vars_into (tree vars, tree fn)
{
  bool change_cfun = fn != current_function_decl;

  if (change_cfun)
    push_cfun (DECL_STRUCT_FUNCTION (fn));

  for (; vars; vars = DECL_CHAIN (vars))
    {
      tree var = vars;

      /* BIND_EXPRs contains also function/type/constant declarations
         we don't need to care about.  */
      if (TREE_CODE (var) != VAR_DECL)
	continue;

      /* Nothing to do in this case.  */
      if (DECL_EXTERNAL (var))
	continue;

      /* Record the variable.  */
      add_local_decl (cfun, var);
    }

  if (change_cfun)
    pop_cfun ();
}

static void
call_graph_add_fn (tree fndecl)
{
  const tree outer = current_function_decl;
  struct function *f = DECL_STRUCT_FUNCTION (fndecl);
  gcc_assert (TREE_CODE (fndecl) == FUNCTION_DECL);

  f->is_cilk_function = 1;
  f->curr_properties = cfun->curr_properties;
  gcc_assert (cfun == DECL_STRUCT_FUNCTION (outer)); 
  gcc_assert (cfun->decl == outer);

  push_cfun (f);
  cgraph_node::create (fndecl);
  pop_cfun_to (outer);
}

static void
set_callers_may_not_allocate_frame (function *fn)
{
  basic_block bb;
  gimple_stmt_iterator gsi;
  gimple *stmt;
  tree called_fn_tree;
  function *called_fn;

  if (fn->cfg == NULL)
    return;

  FOR_EACH_BB_FN (bb, fn)
    {
      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
	{
	  stmt = gsi_stmt (gsi);
	  if (is_gimple_call (stmt))
	    {
	      called_fn_tree = gimple_call_fndecl (stmt);
	      if (called_fn_tree != NULL)
	        {
	          called_fn = DECL_STRUCT_FUNCTION (called_fn_tree);
		  if (called_fn != NULL)
		    called_fn->machine->callers_may_not_allocate_frame = true;
	        }
            }
        }
    }
  return;
}

static void
pop_cfun_to (tree outer)
{
  pop_cfun ();
  current_function_decl = outer;
  gcc_assert (cfun == DECL_STRUCT_FUNCTION (current_function_decl));
  gcc_assert (cfun->decl == current_function_decl);
}

static void
build_function (tree fndecl, tree stmts, tree block)
{
    DECL_INITIAL(fndecl) = block;
    DECL_SAVED_TREE (fndecl) = stmts ;

    tree resdecl = build_decl(input_location,RESULT_DECL, NULL_TREE, integer_type_node);
    DECL_CONTEXT (resdecl) = fndecl;
    DECL_RESULT(fndecl) = resdecl;
    current_function_decl = fndecl;

    if (DECL_STRUCT_FUNCTION(fndecl) == NULL)
        push_struct_function(fndecl);
    else
		push_cfun(DECL_STRUCT_FUNCTION(fndecl));

    cfun->function_end_locus = BUILTINS_LOCATION;

}

/* 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 (tree decl, basic_block bb)
{
  int entry_freq = ENTRY_BLOCK_PTR_FOR_FN
  		     (DECL_STRUCT_FUNCTION (decl))->frequency;
  int freq = bb->frequency;

  if (profile_status_for_fn (DECL_STRUCT_FUNCTION (decl)) == PROFILE_ABSENT)
    return CGRAPH_FREQ_BASE;

  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;
}

static void
afdo_indirect_call (gimple_stmt_iterator *gsi, const icall_target_map &map,
                    bool transform)
{
  gimple gs = gsi_stmt (*gsi);
  tree callee;

  if (map.size () == 0)
    return;
  gcall *stmt = dyn_cast <gcall *> (gs);
  if ((!stmt) || gimple_call_fndecl (stmt) != NULL_TREE)
    return;

  callee = gimple_call_fn (stmt);

  histogram_value hist = gimple_alloc_histogram_value (
      cfun, HIST_TYPE_INDIR_CALL, stmt, callee);
  hist->n_counters = 3;
  hist->hvalue.counters = XNEWVEC (gcov_type, hist->n_counters);
  gimple_add_histogram_value (cfun, stmt, hist);

  gcov_type total = 0;
  icall_target_map::const_iterator max_iter = map.end ();

  for (icall_target_map::const_iterator iter = map.begin ();
       iter != map.end (); ++iter)
    {
      total += iter->second;
      if (max_iter == map.end () || max_iter->second < iter->second)
        max_iter = iter;
    }

  hist->hvalue.counters[0]
      = (unsigned long long)afdo_string_table->get_name (max_iter->first);
  hist->hvalue.counters[1] = max_iter->second;
  hist->hvalue.counters[2] = total;

  if (!transform)
    return;

  struct cgraph_edge *indirect_edge
      = cgraph_node::get (current_function_decl)->get_edge (stmt);
  struct cgraph_node *direct_call = cgraph_node::get_for_asmname (
      get_identifier ((const char *) hist->hvalue.counters[0]));

  if (direct_call == NULL || !check_ic_target (stmt, direct_call))
    return;
  if (DECL_STRUCT_FUNCTION (direct_call->decl) == NULL)
    return;
  struct cgraph_edge *new_edge
      = indirect_edge->make_speculative (direct_call, 0, 0);
  new_edge->redirect_call_stmt_to_callee ();
  gimple_remove_histogram_value (cfun, stmt, hist);
  inline_call (new_edge, true, NULL, NULL, false);
}

static void
convert_to_ssa (tree fndecl)
{
  function *fun = DECL_STRUCT_FUNCTION (fndecl);
  ASSERT_TRUE (fun != NULL);
  ASSERT_EQ (fndecl, fun->decl);

  gimple_opt_pass *build_ssa_pass = make_pass_build_ssa (g);
  push_cfun (fun);
  build_ssa_pass->execute (fun);
  pop_cfun ();
}

symtab_node *
symtab_nonoverwritable_alias (symtab_node *node)
{
  tree new_decl;
  symtab_node *new_node = NULL;

  /* First try to look up existing alias or base object
     (if that is already non-overwritable).  */
  node = symtab_alias_ultimate_target (node, NULL);
  gcc_assert (!node->alias && !node->weakref);
  symtab_for_node_and_aliases (node, symtab_nonoverwritable_alias_1,
		               (void *)&new_node, true);
  if (new_node)
    return new_node;
#ifndef ASM_OUTPUT_DEF
  /* If aliases aren't supported by the assembler, fail.  */
  return NULL;
#endif

  /* Otherwise create a new one.  */
  new_decl = copy_node (node->decl);
  DECL_DLLIMPORT_P (new_decl) = 0;
  DECL_NAME (new_decl) = clone_function_name (node->decl, "localalias");
  if (TREE_CODE (new_decl) == FUNCTION_DECL)
    DECL_STRUCT_FUNCTION (new_decl) = NULL;
  DECL_INITIAL (new_decl) = NULL;
  SET_DECL_ASSEMBLER_NAME (new_decl, DECL_NAME (new_decl));
  SET_DECL_RTL (new_decl, NULL);

  /* Update the properties.  */
  DECL_EXTERNAL (new_decl) = 0;
  if (DECL_ONE_ONLY (node->decl))
    DECL_SECTION_NAME (new_decl) = NULL;
  DECL_COMDAT_GROUP (new_decl) = 0;
  TREE_PUBLIC (new_decl) = 0;
  DECL_COMDAT (new_decl) = 0;
  DECL_WEAK (new_decl) = 0;
  DECL_VIRTUAL_P (new_decl) = 0;
  if (TREE_CODE (new_decl) == FUNCTION_DECL)
    {
      DECL_STATIC_CONSTRUCTOR (new_decl) = 0;
      DECL_STATIC_DESTRUCTOR (new_decl) = 0;
      new_node = cgraph_create_function_alias
				 (new_decl, node->decl);
    }
  else
    new_node = varpool_create_variable_alias (new_decl,
							    node->decl);
  symtab_resolve_alias (new_node, node);  
  gcc_assert (decl_binds_to_current_def_p (new_decl));
  return new_node;
}

/* Check the consistency of profile information.  We can't do that
   in verify_flow_info, as the counts may get invalid for incompletely
   solved graphs, later eliminating of conditionals or roundoff errors.
   It is still practical to have them reported for debugging of simple
   testcases.  */
static void
check_bb_profile (basic_block bb, FILE * file, int indent, int flags)
{
  edge e;
  int sum = 0;
  gcov_type lsum;
  edge_iterator ei;
  struct function *fun = DECL_STRUCT_FUNCTION (current_function_decl);
  char *s_indent = (char *) alloca ((size_t) indent + 1);
  memset ((void *) s_indent, ' ', (size_t) indent);
  s_indent[indent] = '\0';

  if (profile_status_for_function (fun) == PROFILE_ABSENT)
    return;

  if (bb != EXIT_BLOCK_PTR_FOR_FUNCTION (fun))
    {
      FOR_EACH_EDGE (e, ei, bb->succs)
	sum += e->probability;
      if (EDGE_COUNT (bb->succs) && abs (sum - REG_BR_PROB_BASE) > 100)
	fprintf (file, "%s%sInvalid sum of outgoing probabilities %.1f%%\n",
		 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
		 sum * 100.0 / REG_BR_PROB_BASE);
      lsum = 0;
      FOR_EACH_EDGE (e, ei, bb->succs)
	lsum += e->count;
      if (EDGE_COUNT (bb->succs)
	  && (lsum - bb->count > 100 || lsum - bb->count < -100))
	fprintf (file, "%s%sInvalid sum of outgoing counts %i, should be %i\n",
		 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
		 (int) lsum, (int) bb->count);
    }
    if (bb != ENTRY_BLOCK_PTR_FOR_FUNCTION (fun))
    {
      sum = 0;
      FOR_EACH_EDGE (e, ei, bb->preds)
	sum += EDGE_FREQUENCY (e);
      if (abs (sum - bb->frequency) > 100)
	fprintf (file,
		 "%s%sInvalid sum of incoming frequencies %i, should be %i\n",
		 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
		 sum, bb->frequency);
      lsum = 0;
      FOR_EACH_EDGE (e, ei, bb->preds)
	lsum += e->count;
      if (lsum - bb->count > 100 || lsum - bb->count < -100)
	fprintf (file, "%s%sInvalid sum of incoming counts %i, should be %i\n",
		 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
		 (int) lsum, (int) bb->count);
    }
}

void xml_local_decls(int indent, FILE *out)
{
    tree var;
    fprintf(out, "%s<locals>\n", spc(indent));
    indent += INDENT;

    for (var = DECL_STRUCT_FUNCTION(current_function_decl)->local_decls;
            var;
            var = TREE_CHAIN(var))
        xml_local_decl(TREE_VALUE(var), indent, out);

    indent -= INDENT;
    fprintf(out, "%s</locals>\n", spc(indent));
}

void
gimple_set_body (tree fndecl, gimple_seq seq)
{
  struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
  if (fn == NULL)
    {
      /* If FNDECL still does not have a function structure associated
	 with it, then it does not make sense for it to receive a
	 GIMPLE body.  */
      gcc_assert (seq == NULL);
    }
  else
    fn->gimple_body = seq;
}

static funct_state
analyze_function (struct cgraph_node *fn, bool ipa)
{
  tree decl = fn->decl;
  funct_state l;
  basic_block this_block;

  l = XCNEW (struct funct_state_d);
  l->pure_const_state = IPA_CONST;
  l->state_previously_known = IPA_NEITHER;
  l->looping_previously_known = true;
  l->looping = false;
  l->can_throw = false;
  state_from_flags (&l->state_previously_known, &l->looping_previously_known,
		    flags_from_decl_or_type (fn->decl),
		    fn->cannot_return_p ());

  if (fn->thunk.thunk_p || fn->alias)
    {
      /* Thunk gets propagated through, so nothing interesting happens.  */
      gcc_assert (ipa);
      return l;
    }

  if (dump_file)
    {
      fprintf (dump_file, "\n\n local analysis of %s\n ",
	       fn->name ());
    }

  push_cfun (DECL_STRUCT_FUNCTION (decl));

  FOR_EACH_BB_FN (this_block, cfun)
    {
      gimple_stmt_iterator gsi;
      struct walk_stmt_info wi;

      memset (&wi, 0, sizeof (wi));
      for (gsi = gsi_start_bb (this_block);
	   !gsi_end_p (gsi);
	   gsi_next (&gsi))
	{
	  check_stmt (&gsi, l, ipa);
	  if (l->pure_const_state == IPA_NEITHER && l->looping && l->can_throw)
	    goto end;
	}
    }