1/* Data type conversion
2   Copyright (C) 1987-2020 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20
21/* This file contains the functions for converting expressions to
22   different data types for the translation of the gfortran internal
23   representation to GIMPLE.  The only entry point is `convert'.  */
24
25#include "config.h"
26#include "system.h"
27#include "coretypes.h"
28#include "tree.h"
29#include "fold-const.h"
30#include "convert.h"
31
32#include "gfortran.h"
33#include "trans.h"
34#include "trans-types.h"
35
36/* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
37   or validate its data type for a GIMPLE `if' or `while' statement.
38
39   The resulting type should always be `logical_type_node'.  */
40
41static tree
42truthvalue_conversion (tree expr)
43{
44  switch (TREE_CODE (TREE_TYPE (expr)))
45    {
46    case BOOLEAN_TYPE:
47      if (TREE_TYPE (expr) == logical_type_node)
48	return expr;
49      else if (COMPARISON_CLASS_P (expr))
50	{
51	  TREE_TYPE (expr) = logical_type_node;
52	  return expr;
53	}
54      else if (TREE_CODE (expr) == NOP_EXPR)
55        return fold_build1_loc (input_location, NOP_EXPR,
56				logical_type_node,
57				TREE_OPERAND (expr, 0));
58      else
59        return fold_build1_loc (input_location, NOP_EXPR,
60				logical_type_node,
61				expr);
62
63    case INTEGER_TYPE:
64      if (TREE_CODE (expr) == INTEGER_CST)
65	return integer_zerop (expr) ? logical_false_node
66	  : logical_true_node;
67      else
68        return fold_build2_loc (input_location, NE_EXPR,
69				logical_type_node,
70				expr, build_int_cst (TREE_TYPE (expr), 0));
71
72    default:
73      gcc_unreachable ();
74    }
75}
76
77/* Create an expression whose value is that of EXPR,
78   converted to type TYPE.  The TREE_TYPE of the value
79   is always TYPE.  This function implements all reasonable
80   conversions; callers should filter out those that are
81   not permitted by the language being compiled.  */
82
83tree
84convert (tree type, tree expr)
85{
86  tree e = expr;
87  enum tree_code code;
88
89  if (type == TREE_TYPE (expr))
90    return expr;
91
92  if (TREE_CODE (type) == ERROR_MARK
93      || TREE_CODE (expr) == ERROR_MARK
94      || TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
95    return expr;
96
97  gcc_checking_assert (TREE_CODE (TREE_TYPE (expr)) != VOID_TYPE);
98
99  if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr)))
100    return fold_build1_loc (input_location, NOP_EXPR, type, expr);
101
102  code = TREE_CODE (type);
103  if (code == VOID_TYPE)
104    return fold_build1_loc (input_location, CONVERT_EXPR, type, e);
105  if (code == BOOLEAN_TYPE)
106    return fold_build1_loc (input_location, NOP_EXPR, type,
107			    truthvalue_conversion (e));
108  if (code == INTEGER_TYPE)
109    return fold (convert_to_integer (type, e));
110  if (code == POINTER_TYPE || code == REFERENCE_TYPE)
111    return fold (convert_to_pointer (type, e));
112  if (code == REAL_TYPE)
113    return fold (convert_to_real (type, e));
114  if (code == COMPLEX_TYPE)
115    return fold (convert_to_complex (type, e));
116  if (code == VECTOR_TYPE)
117    return fold (convert_to_vector (type, e));
118
119  gcc_unreachable ();
120}
121
122