1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
dnl A function to detect whether C++ provides exact output for doubles.
dnl Copyright (C) 2001-2010 Roberto Bagnara <bagnara@cs.unipr.it>
dnl Copyright (C) 2010-2011 BUGSENG srl (http://bugseng.com)
dnl
dnl This file is part of the Parma Polyhedra Library (PPL).
dnl
dnl The PPL is free software; you can redistribute it and/or modify it
dnl under the terms of the GNU General Public License as published by the
dnl Free Software Foundation; either version 3 of the License, or (at your
dnl option) any later version.
dnl
dnl The PPL is distributed in the hope that it will be useful, but WITHOUT
dnl ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
dnl FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
dnl for more details.
dnl
dnl You should have received a copy of the GNU General Public License
dnl along with this program; if not, write to the Free Software Foundation,
dnl Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1307, USA.
dnl
dnl For the most up-to-date information see the Parma Polyhedra Library
dnl site: http://www.cs.unipr.it/ppl/ .
AC_DEFUN([AC_CXX_DOUBLE_EXACT_OUTPUT],
[
AC_REQUIRE([AC_C_BIGENDIAN])
dnl AC_REQUIRE([AC_CXX_DOUBLE_BINARY_FORMAT])
ac_save_CPPFLAGS="$CPPFLAGS"
ac_save_LIBS="$LIBS"
AC_LANG_PUSH(C++)
AC_MSG_CHECKING([whether C++ provides exact output for doubles])
AC_RUN_IFELSE([AC_LANG_SOURCE([[
#include <limits>
#ifdef HAVE_STDINT_H
#ifndef __STDC_LIMIT_MACROS
#define __STDC_LIMIT_MACROS 1
#endif
#include <stdint.h>
#endif
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif
#include <sstream>
/* Unique (nonzero) code for the IEEE 754 Single Precision
floating point format. */
# define PPL_FLOAT_IEEE754_SINGLE 1
/* Unique (nonzero) code for the IEEE 754 Double Precision
floating point format. */
# define PPL_FLOAT_IEEE754_DOUBLE 2
/* Unique (nonzero) code for the IEEE 754 Quad Precision
floating point format. */
# define PPL_FLOAT_IEEE754_QUAD 3
/* Unique (nonzero) code for the Intel Double-Extended
floating point format. */
# define PPL_FLOAT_INTEL_DOUBLE_EXTENDED 4
bool
check(double value, const char* text) {
std::ostringstream ss;
ss.precision(10000);
ss << value;
return ss.str() == text;
}
#if SIZEOF_DOUBLE == 8
double
convert(uint32_t msp, uint32_t lsp) {
union {
double value;
struct {
#ifdef WORDS_BIGENDIAN
uint32_t msp;
uint32_t lsp;
#else
uint32_t lsp;
uint32_t msp;
#endif
} parts;
} u;
u.parts.msp = msp;
u.parts.lsp = lsp;
return u.value;
}
#if PPL_CXX_DOUBLE_BINARY_FORMAT == PPL_FLOAT_IEEE754_DOUBLE
int
main() {
if (check(convert(0xaaacccaaUL, 0xacccaaacUL),
"-4.018242396032647085467373664662028399901175154542925376476863248797653889888945947404163925979898721593782464256360719269163883854613473748830842329884157359816532025640075051481726120707111709993717456369512975427023957197464411926714771905463723621065863511603311053477227687835693359375e-103")
&& check(convert(0xcccaaaccUL, 0xcaaacccaUL),
"-85705035845709846787631445265530356117787053916987832397725696")
&& check(convert(0x00000000UL, 0x00000001UL),
"4.940656458412465441765687928682213723650598026143247644255856825006755072702087518652998363616359923797965646954457177309266567103559397963987747960107818781263007131903114045278458171678489821036887186360569987307230500063874091535649843873124733972731696151400317153853980741262385655911710266585566867681870395603106249319452715914924553293054565444011274801297099995419319894090804165633245247571478690147267801593552386115501348035264934720193790268107107491703332226844753335720832431936092382893458368060106011506169809753078342277318329247904982524730776375927247874656084778203734469699533647017972677717585125660551199131504891101451037862738167250955837389733598993664809941164205702637090279242767544565229087538682506419718265533447265625e-324")
&& check(convert(0x80000000UL, 0x00000001UL),
"-4.940656458412465441765687928682213723650598026143247644255856825006755072702087518652998363616359923797965646954457177309266567103559397963987747960107818781263007131903114045278458171678489821036887186360569987307230500063874091535649843873124733972731696151400317153853980741262385655911710266585566867681870395603106249319452715914924553293054565444011274801297099995419319894090804165633245247571478690147267801593552386115501348035264934720193790268107107491703332226844753335720832431936092382893458368060106011506169809753078342277318329247904982524730776375927247874656084778203734469699533647017972677717585125660551199131504891101451037862738167250955837389733598993664809941164205702637090279242767544565229087538682506419718265533447265625e-324"))
return 0;
else
return 1;
}
#else // PPL_CXX_DOUBLE_BINARY_FORMAT != PPL_FLOAT_IEEE754_DOUBLE
int
main() {
return 1;
}
#endif // PPL_CXX_DOUBLE_BINARY_FORMAT != PPL_FLOAT_IEEE754_DOUBLE
#else // SIZEOF_DOUBLE != 8
int
main() {
return 1;
}
#endif // SIZEOF_DOUBLE != 8
]])],
AC_MSG_RESULT(yes)
ac_cxx_double_exact_output=1,
AC_MSG_RESULT(no)
ac_cxx_double_exact_output=0,
AC_MSG_RESULT([assuming not])
ac_cxx_double_exact_output=0)
AC_DEFINE_UNQUOTED(PPL_CXX_DOUBLE_EXACT_OUTPUT, $ac_cxx_double_exact_output,
[Not zero if C++ supports exact output for doubles.])
AC_LANG_POP(C++)
CPPFLAGS="$ac_save_CPPFLAGS"
LIBS="$ac_save_LIBS"
])
|
