コード例 #1
0
static void
get_asm_expr_operands (gimple stmt)
{
  size_t i, noutputs;
  const char **oconstraints;
  const char *constraint;
  bool allows_mem, allows_reg, is_inout;

  noutputs = gimple_asm_noutputs (stmt);
  oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *));

  /* Gather all output operands.  */
  for (i = 0; i < gimple_asm_noutputs (stmt); i++)
    {
      tree link = gimple_asm_output_op (stmt, i);
      constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
      oconstraints[i] = constraint;
      parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
	                       &allows_reg, &is_inout);

      /* This should have been split in gimplify_asm_expr.  */
      gcc_assert (!allows_reg || !is_inout);

      /* Memory operands are addressable.  Note that STMT needs the
	 address of this operand.  */
      if (!allows_reg && allows_mem)
	mark_address_taken (TREE_VALUE (link));

      get_expr_operands (stmt, &TREE_VALUE (link), opf_def | opf_not_non_addressable);
    }

  /* Gather all input operands.  */
  for (i = 0; i < gimple_asm_ninputs (stmt); i++)
    {
      tree link = gimple_asm_input_op (stmt, i);
      constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
      parse_input_constraint (&constraint, 0, 0, noutputs, 0, oconstraints,
	                      &allows_mem, &allows_reg);

      /* Memory operands are addressable.  Note that STMT needs the
	 address of this operand.  */
      if (!allows_reg && allows_mem)
	mark_address_taken (TREE_VALUE (link));

      get_expr_operands (stmt, &TREE_VALUE (link), opf_not_non_addressable);
    }

  /* Clobber all memory and addressable symbols for asm ("" : : : "memory");  */
  if (gimple_asm_clobbers_memory_p (stmt))
    add_virtual_operand (stmt, opf_def);
}
コード例 #2
0
/* Look into pointer pointed to by GSIP and figure out what interesting side
   effects it has.  */
static void
check_stmt (gimple_stmt_iterator *gsip, funct_state local, bool ipa)
{
  gimple stmt = gsi_stmt (*gsip);

  if (is_gimple_debug (stmt))
    return;

  if (dump_file)
    {
      fprintf (dump_file, "  scanning: ");
      print_gimple_stmt (dump_file, stmt, 0, 0);
    }

  if (gimple_has_volatile_ops (stmt)
      && !gimple_clobber_p (stmt))
    {
      local->pure_const_state = IPA_NEITHER;
      if (dump_file)
	fprintf (dump_file, "    Volatile stmt is not const/pure\n");
    }

  /* Look for loads and stores.  */
  walk_stmt_load_store_ops (stmt, local,
			    ipa ? check_ipa_load : check_load,
			    ipa ? check_ipa_store :  check_store);

  if (gimple_code (stmt) != GIMPLE_CALL
      && stmt_could_throw_p (stmt))
    {
      if (cfun->can_throw_non_call_exceptions)
	{
	  if (dump_file)
	    fprintf (dump_file, "    can throw; looping\n");
	  local->looping = true;
	}
      if (stmt_can_throw_external (stmt))
	{
	  if (dump_file)
	    fprintf (dump_file, "    can throw externally\n");
	  local->can_throw = true;
	}
      else
	if (dump_file)
	  fprintf (dump_file, "    can throw\n");
    }
  switch (gimple_code (stmt))
    {
    case GIMPLE_CALL:
      check_call (local, stmt, ipa);
      break;
    case GIMPLE_LABEL:
      if (DECL_NONLOCAL (gimple_label_label (stmt)))
	/* Target of long jump. */
	{
          if (dump_file)
            fprintf (dump_file, "    nonlocal label is not const/pure\n");
	  local->pure_const_state = IPA_NEITHER;
	}
      break;
    case GIMPLE_ASM:
      if (gimple_asm_clobbers_memory_p (stmt))
	{
	  if (dump_file)
	    fprintf (dump_file, "    memory asm clobber is not const/pure\n");
	  /* Abandon all hope, ye who enter here. */
	  local->pure_const_state = IPA_NEITHER;
	}
      if (gimple_asm_volatile_p (stmt))
	{
	  if (dump_file)
	    fprintf (dump_file, "    volatile is not const/pure\n");
	  /* Abandon all hope, ye who enter here. */
	  local->pure_const_state = IPA_NEITHER;
          local->looping = true;
	}
      return;
    default:
      break;
    }
}