* arm.c (FL_WBUF): Define.
[official-gcc.git] / gcc / fortran / convert.c
bloba0298f22784725024551f46277613393bac1fe89
1 /* Language-level data type conversion for GNU C.
2 Copyright (C) 1987, 1988, 1991, 1998, 2002 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 2, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to the Free
18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
19 02111-1307, USA. */
22 /* This file contains the functions for converting C expressions
23 to different data types. The only entry point is `convert'.
24 Every language front end must have a `convert' function
25 but what kind of conversions it does will depend on the language. */
27 /* copied from the f77 frontend I think */
29 /* copied from c-convert.c without significant modification*/
30 /* Change of width--truncation and extension of integers or reals--
31 is represented with NOP_EXPR. Proper functioning of many things
32 assumes that no other conversions can be NOP_EXPRs.
35 /* I've added support for WITH_RECORD_EXPR. */
37 #include "config.h"
38 #include "system.h"
39 #include "coretypes.h"
40 #include "tree.h"
41 #include "flags.h"
42 #include "convert.h"
43 #include "toplev.h"
44 #include "gfortran.h"
45 #include "trans.h"
48 Conversion between integer and pointer is represented with CONVERT_EXPR.
49 Converting integer to real uses FLOAT_EXPR
50 and real to integer uses FIX_TRUNC_EXPR.
52 Here is a list of all the functions that assume that widening and
53 narrowing is always done with a NOP_EXPR:
54 In convert.c, convert_to_integer.
55 In c-typeck.c, build_binary_op (boolean ops), and
56 c_common_truthvalue_conversion.
57 In expr.c: expand_expr, for operands of a MULT_EXPR.
58 In fold-const.c: fold.
59 In tree.c: get_narrower and get_unwidened. */
61 /* Subroutines of `convert'. */
65 /* Create an expression whose value is that of EXPR,
66 converted to type TYPE. The TREE_TYPE of the value
67 is always TYPE. This function implements all reasonable
68 conversions; callers should filter out those that are
69 not permitted by the language being compiled. */
70 /* We are assuming that given a SIMPLE val, the result will be a SIMPLE rhs.
71 If this is not the case, we will abort with an internal error. */
72 tree
73 convert (tree type, tree expr)
75 tree e = expr;
76 enum tree_code code = TREE_CODE (type);
78 if (type == TREE_TYPE (expr)
79 || TREE_CODE (expr) == ERROR_MARK
80 || code == ERROR_MARK || TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
81 return expr;
83 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr)))
84 return fold_build1 (NOP_EXPR, type, expr);
85 if (TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
86 return error_mark_node;
87 if (TREE_CODE (TREE_TYPE (expr)) == VOID_TYPE)
89 error ("void value not ignored as it ought to be");
90 return error_mark_node;
92 if (code == VOID_TYPE)
93 return build1 (CONVERT_EXPR, type, e);
94 #if 0
95 /* This is incorrect. A truncation can't be stripped this way.
96 Extensions will be stripped by the use of get_unwidened. */
97 if (TREE_CODE (expr) == NOP_EXPR)
98 return convert (type, TREE_OPERAND (expr, 0));
99 #endif
100 if (code == INTEGER_TYPE || code == ENUMERAL_TYPE)
101 return fold (convert_to_integer (type, e));
102 if (code == BOOLEAN_TYPE)
104 e = gfc_truthvalue_conversion (e);
106 /* If we have a NOP_EXPR, we must fold it here to avoid
107 infinite recursion between fold () and convert (). */
108 if (TREE_CODE (e) == NOP_EXPR)
109 return fold_build1 (NOP_EXPR, type, TREE_OPERAND (e, 0));
110 else
111 return fold_build1 (NOP_EXPR, type, e);
113 if (code == POINTER_TYPE || code == REFERENCE_TYPE)
114 return fold (convert_to_pointer (type, e));
115 if (code == REAL_TYPE)
116 return fold (convert_to_real (type, e));
117 if (code == COMPLEX_TYPE)
118 return fold (convert_to_complex (type, e));
119 if (code == VECTOR_TYPE)
120 return fold (convert_to_vector (type, e));
122 error ("conversion to non-scalar type requested");
123 return error_mark_node;