C++ TREE_CODE_CLASS函数代码示例

void
gimple_cond_get_ops_from_tree (tree cond, enum tree_code *code_p,
                               tree *lhs_p, tree *rhs_p)
{
  gcc_assert (TREE_CODE_CLASS (TREE_CODE (cond)) == tcc_comparison
	      || TREE_CODE (cond) == TRUTH_NOT_EXPR
	      || is_gimple_min_invariant (cond)
	      || SSA_VAR_P (cond));

  extract_ops_from_tree (cond, code_p, lhs_p, rhs_p);

  /* Canonicalize conditionals of the form 'if (!VAL)'.  */
  if (*code_p == TRUTH_NOT_EXPR)
    {
      *code_p = EQ_EXPR;
      gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
      *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
    }
  /* Canonicalize conditionals of the form 'if (VAL)'  */
  else if (TREE_CODE_CLASS (*code_p) != tcc_comparison)
    {
      *code_p = NE_EXPR;
      gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
      *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
    }
}

tree
gimple_simplify (enum tree_code code, tree type,
		 tree op0, tree op1,
		 gimple_seq *seq, tree (*valueize)(tree))
{
  if (constant_for_folding (op0) && constant_for_folding (op1))
    {
      tree res = const_binop (code, type, op0, op1);
      if (res != NULL_TREE
	  && CONSTANT_CLASS_P (res))
	return res;
    }

  /* Canonicalize operand order both for matching and fallback stmt
     generation.  */
  if ((commutative_tree_code (code)
       || TREE_CODE_CLASS (code) == tcc_comparison)
      && tree_swap_operands_p (op0, op1, false))
    {
      tree tem = op0;
      op0 = op1;
      op1 = tem;
      if (TREE_CODE_CLASS (code) == tcc_comparison)
	code = swap_tree_comparison (code);
    }

  code_helper rcode;
  tree ops[3] = {};
  if (!gimple_simplify (&rcode, ops, seq, valueize,
			code, type, op0, op1))
    return NULL_TREE;
  return maybe_push_res_to_seq (rcode, type, ops, seq);
}

bool
gimple_resimplify2 (gimple_seq *seq,
		    code_helper *res_code, tree type, tree *res_ops,
		    tree (*valueize)(tree))
{
  if (constant_for_folding (res_ops[0]) && constant_for_folding (res_ops[1]))
    {
      tree tem = NULL_TREE;
      if (res_code->is_tree_code ())
	tem = const_binop (*res_code, type, res_ops[0], res_ops[1]);
      else
	tem = fold_const_call (combined_fn (*res_code), type,
			       res_ops[0], res_ops[1]);
      if (tem != NULL_TREE
	  && CONSTANT_CLASS_P (tem))
	{
	  if (TREE_OVERFLOW_P (tem))
	    tem = drop_tree_overflow (tem);
	  res_ops[0] = tem;
	  res_ops[1] = NULL_TREE;
	  res_ops[2] = NULL_TREE;
	  *res_code = TREE_CODE (res_ops[0]);
	  return true;
	}
    }

  /* Canonicalize operand order.  */
  bool canonicalized = false;
  if (res_code->is_tree_code ()
      && (TREE_CODE_CLASS ((enum tree_code) *res_code) == tcc_comparison
	  || commutative_tree_code (*res_code))
      && tree_swap_operands_p (res_ops[0], res_ops[1]))
    {
      std::swap (res_ops[0], res_ops[1]);
      if (TREE_CODE_CLASS ((enum tree_code) *res_code) == tcc_comparison)
	*res_code = swap_tree_comparison (*res_code);
      canonicalized = true;
    }

  code_helper res_code2;
  tree res_ops2[3] = {};
  if (gimple_simplify (&res_code2, res_ops2, seq, valueize,
		       *res_code, type, res_ops[0], res_ops[1]))
    {
      *res_code = res_code2;
      res_ops[0] = res_ops2[0];
      res_ops[1] = res_ops2[1];
      res_ops[2] = res_ops2[2];
      return true;
    }

  return canonicalized;
}

/* Check whether G is a potential conditional compare candidate.  */
static bool
ccmp_candidate_p (gimple *g)
{
  tree rhs = gimple_assign_rhs_to_tree (g);
  tree lhs, op0, op1;
  gimple *gs0, *gs1;
  enum tree_code tcode, tcode0, tcode1;
  tcode = TREE_CODE (rhs);

  if (tcode != BIT_AND_EXPR && tcode != BIT_IOR_EXPR)
    return false;

  lhs = gimple_assign_lhs (g);
  op0 = TREE_OPERAND (rhs, 0);
  op1 = TREE_OPERAND (rhs, 1);

  if ((TREE_CODE (op0) != SSA_NAME) || (TREE_CODE (op1) != SSA_NAME)
      || !has_single_use (lhs))
    return false;

  gs0 = get_gimple_for_ssa_name (op0);
  gs1 = get_gimple_for_ssa_name (op1);
  if (!gs0 || !gs1 || !is_gimple_assign (gs0) || !is_gimple_assign (gs1)
      /* g, gs0 and gs1 must be in the same basic block, since current stage
	 is out-of-ssa.  We can not guarantee the correctness when forwording
	 the gs0 and gs1 into g whithout DATAFLOW analysis.  */
      || gimple_bb (gs0) != gimple_bb (gs1)
      || gimple_bb (gs0) != gimple_bb (g))
    return false;

  if (!(INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (gs0)))
       || POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (gs0))))
      || !(INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (gs1)))
	   || POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (gs1)))))
    return false;

  tcode0 = gimple_assign_rhs_code (gs0);
  tcode1 = gimple_assign_rhs_code (gs1);
  if (TREE_CODE_CLASS (tcode0) == tcc_comparison
      && TREE_CODE_CLASS (tcode1) == tcc_comparison)
    return true;
  if (TREE_CODE_CLASS (tcode0) == tcc_comparison
      && ccmp_candidate_p (gs1))
    return true;
  else if (TREE_CODE_CLASS (tcode1) == tcc_comparison
	   && ccmp_candidate_p (gs0))
    return true;
  /* We skip ccmp_candidate_p (gs1) && ccmp_candidate_p (gs0) since
     there is no way to set the CC flag.  */
  return false;
}

static struct loop *
outermost_invariant_loop_expr (tree expr, struct loop *loop)
{
  enum tree_code_class codeclass = TREE_CODE_CLASS (TREE_CODE (expr));
  unsigned i, nops;
  struct loop *max_loop = superloop_at_depth (loop, 1), *aloop;

  if (TREE_CODE (expr) == SSA_NAME
      || TREE_CODE (expr) == INTEGER_CST
      || is_gimple_min_invariant (expr))
    return outermost_invariant_loop (expr, loop);

  if (codeclass != tcc_unary
      && codeclass != tcc_binary
      && codeclass != tcc_expression
      && codeclass != tcc_vl_exp
      && codeclass != tcc_comparison)
    return NULL;

  nops = TREE_OPERAND_LENGTH (expr);
  for (i = 0; i < nops; i++)
    {
      aloop = outermost_invariant_loop_expr (TREE_OPERAND (expr, i), loop);
      if (!aloop)
	return NULL;

      if (flow_loop_nested_p (max_loop, aloop))
	max_loop = aloop;
    }

  return max_loop;
}

static tree get_string_cst(tree var)
{
	if (var == NULL_TREE)
		return NULL_TREE;

	if (TREE_CODE(var) == STRING_CST)
		return var;

	switch (TREE_CODE_CLASS(TREE_CODE(var))) {
	case tcc_expression:
	case tcc_reference: {
		int i;

		for (i = 0; i < TREE_OPERAND_LENGTH(var); i++) {
			tree ret = get_string_cst(TREE_OPERAND(var, i));
			if (ret != NULL_TREE)
				return ret;
		}
		break;
	}

	default:
		break;
	}

	return NULL_TREE;
}

/* Langhook for tree_size: determine size of our 'x' and 'c' nodes.  */
size_t
cp_tree_size (enum tree_code code)
{
  gcc_checking_assert (code >= NUM_TREE_CODES);
  switch (code)
    {
    case PTRMEM_CST:		return sizeof (ptrmem_cst);
    case BASELINK:		return sizeof (tree_baselink);
    case TEMPLATE_PARM_INDEX:	return sizeof (template_parm_index);
    case DEFAULT_ARG:		return sizeof (tree_default_arg);
    case DEFERRED_NOEXCEPT:	return sizeof (tree_deferred_noexcept);
    case OVERLOAD:		return sizeof (tree_overload);
    case STATIC_ASSERT:         return sizeof (tree_static_assert);
    case TYPE_ARGUMENT_PACK:
    case TYPE_PACK_EXPANSION:	return sizeof (tree_type_non_common);
    case NONTYPE_ARGUMENT_PACK:
    case EXPR_PACK_EXPANSION:	return sizeof (tree_exp);
    case ARGUMENT_PACK_SELECT:	return sizeof (tree_argument_pack_select);
    case TRAIT_EXPR:		return sizeof (tree_trait_expr);
    case LAMBDA_EXPR:           return sizeof (tree_lambda_expr);
    case TEMPLATE_INFO:         return sizeof (tree_template_info);
    case CONSTRAINT_INFO:       return sizeof (tree_constraint_info);
    case USERDEF_LITERAL:	return sizeof (tree_userdef_literal);
    case TEMPLATE_DECL:		return sizeof (tree_template_decl);
    default:
      switch (TREE_CODE_CLASS (code))
	{
	case tcc_declaration:	return sizeof (tree_decl_non_common);
	case tcc_type:		return sizeof (tree_type_non_common);
	default: gcc_unreachable ();
	}
    }
  /* NOTREACHED */
}

static tree
get_expr_type (enum tree_code code, tree op)
{
  return (TREE_CODE_CLASS (code) == tcc_comparison)
	 ? boolean_type_node
	 : TREE_TYPE (op);
}

static void set_based_decl_codes(const_tree type, struct decl_hash *decl_hash_data)
{
	gcc_assert(type != NULL_TREE);
	gcc_assert(TREE_CODE_CLASS(TREE_CODE(type)) == tcc_type);

	while (type && decl_hash_data->tree_codes_len < CODES_LIMIT) {
		decl_hash_data->tree_codes[decl_hash_data->tree_codes_len] = get_tree_code(type);
		decl_hash_data->tree_codes_len++;
		type = TREE_TYPE(type);
	}
}

static bool
can_propagate_from (gimple def_stmt)
{
  use_operand_p use_p;
  ssa_op_iter iter;

  gcc_assert (is_gimple_assign (def_stmt));

  /* If the rhs has side-effects we cannot propagate from it.  */
  if (gimple_has_volatile_ops (def_stmt))
    return false;

  /* If the rhs is a load we cannot propagate from it.  */
  if (TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_reference
      || TREE_CODE_CLASS (gimple_assign_rhs_code (def_stmt)) == tcc_declaration)
    return false;

  /* Constants can be always propagated.  */
  if (gimple_assign_single_p (def_stmt)
      && is_gimple_min_invariant (gimple_assign_rhs1 (def_stmt)))
    return true;

  /* We cannot propagate ssa names that occur in abnormal phi nodes.  */
  FOR_EACH_SSA_USE_OPERAND (use_p, def_stmt, iter, SSA_OP_USE)
    if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p)))
      return false;

  /* If the definition is a conversion of a pointer to a function type,
     then we can not apply optimizations as some targets require
     function pointers to be canonicalized and in this case this
     optimization could eliminate a necessary canonicalization.  */
  if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt)))
    {
      tree rhs = gimple_assign_rhs1 (def_stmt);
      if (POINTER_TYPE_P (TREE_TYPE (rhs))
          && TREE_CODE (TREE_TYPE (TREE_TYPE (rhs))) == FUNCTION_TYPE)
        return false;
    }

  return true;
}

void
recalculate_side_effects (tree t)
{
  enum tree_code code = TREE_CODE (t);
  int len = TREE_CODE_LENGTH (code);
  int i;

  switch (TREE_CODE_CLASS (code))
    {
    case tcc_expression:
      switch (code)
	{
	case INIT_EXPR:
	case MODIFY_EXPR:
	case VA_ARG_EXPR:
	case PREDECREMENT_EXPR:
	case PREINCREMENT_EXPR:
	case POSTDECREMENT_EXPR:
	case POSTINCREMENT_EXPR:
	  /* All of these have side-effects, no matter what their
	     operands are.  */
	  return;

	default:
	  break;
	}
      /* Fall through.  */

    case tcc_comparison:  /* a comparison expression */
    case tcc_unary:       /* a unary arithmetic expression */
    case tcc_binary:      /* a binary arithmetic expression */
    case tcc_reference:   /* a reference */
      TREE_SIDE_EFFECTS (t) = TREE_THIS_VOLATILE (t);
      for (i = 0; i < len; ++i)
	{
	  tree op = TREE_OPERAND (t, i);
	  if (op && TREE_SIDE_EFFECTS (op))
	    TREE_SIDE_EFFECTS (t) = 1;
	}
      break;

    default:
      /* Can never be used with non-expressions.  */
      gcc_unreachable ();
   }
}

static void
build_and_record_new_cond (enum tree_code code,
                           tree op0, tree op1,
                           vec<cond_equivalence> *p,
			   bool val = true)
{
  cond_equivalence c;
  struct hashable_expr *cond = &c.cond;

  gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison);

  cond->type = boolean_type_node;
  cond->kind = EXPR_BINARY;
  cond->ops.binary.op = code;
  cond->ops.binary.opnd0 = op0;
  cond->ops.binary.opnd1 = op1;

  c.value = val ? boolean_true_node : boolean_false_node;
  p->safe_push (c);
}

static bool
cilk_ignorable_spawn_rhs_op (tree exp)
{
  enum tree_code code = TREE_CODE (exp);
  switch (TREE_CODE_CLASS (code))
    {
    case tcc_expression:
      return code == ADDR_EXPR;
    case tcc_comparison:
      /* We need the spawn as operand 0 for now.   That's where it
	 appears in the only case we really care about, conversion
	 to bool.  */
      return (TREE_CODE (TREE_OPERAND (exp, 1)) == INTEGER_CST);
    case tcc_unary:
    case tcc_reference:
      return true;
    default:
      return false;
    }
}

bool
is_gimple_formal_tmp_rhs (tree t)
{
  enum tree_code code = TREE_CODE (t);

  switch (TREE_CODE_CLASS (code))
    {
    case tcc_unary:
    case tcc_binary:
    case tcc_comparison:
      return true;

    default:
      break;
    }

  switch (code)
    {
    case TRUTH_NOT_EXPR:
    case TRUTH_AND_EXPR:
    case TRUTH_OR_EXPR:
    case TRUTH_XOR_EXPR:
    case ADDR_EXPR:
    case CALL_EXPR:
    case CONSTRUCTOR:
    case COMPLEX_EXPR:
    case INTEGER_CST:
    case REAL_CST:
    case STRING_CST:
    case COMPLEX_CST:
    case VECTOR_CST:
    case OBJ_TYPE_REF:
    case ASSERT_EXPR:
      return true;

    default:
      break;
    }

  return is_gimple_lvalue (t) || is_gimple_val (t);
}

tree
build_stmt (location_t loc, enum tree_code code, ...)
{
  tree ret;
  int length, i;
  va_list p;
  bool side_effects;

  /* This function cannot be used to construct variably-sized nodes.  */
  gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);

  va_start (p, code);

  ret = make_node (code);
  TREE_TYPE (ret) = void_type_node;
  length = TREE_CODE_LENGTH (code);
  SET_EXPR_LOCATION (ret, loc);

  /* TREE_SIDE_EFFECTS will already be set for statements with
     implicit side effects.  Here we make sure it is set for other
     expressions by checking whether the parameters have side
     effects.  */

  side_effects = false;
  for (i = 0; i < length; i++)
    {
      tree t = va_arg (p, tree);
      if (t && !TYPE_P (t))
	side_effects |= TREE_SIDE_EFFECTS (t);
      TREE_OPERAND (ret, i) = t;
    }

  TREE_SIDE_EFFECTS (ret) |= side_effects;

  va_end (p);
  return ret;
}