Mercurial > gnulib
annotate m4/exponentl.m4 @ 40196:e63f5d3edab5
relocatable-prog: Update documentation.
* doc/relocatable-maint.texi (Supporting Relocation): Update to match
the recent changes.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sun, 24 Feb 2019 01:49:15 +0100 |
parents | b06060465f09 |
children |
rev | line source |
---|---|
18993
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
1 # exponentl.m4 serial 4 |
40057
b06060465f09
maint: Run 'make update-copyright'
Paul Eggert <eggert@cs.ucla.edu>
parents:
19484
diff
changeset
|
2 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc. |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
3 dnl This file is free software; the Free Software Foundation |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
4 dnl gives unlimited permission to copy and/or distribute it, |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
5 dnl with or without modifications, as long as this notice is preserved. |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
6 AC_DEFUN([gl_LONG_DOUBLE_EXPONENT_LOCATION], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
7 [ |
11053
90ea94356c75
Don't use AC_REQUIRE([AC_C_BIGENDIAN]).
Bruno Haible <bruno@clisp.org>
parents:
10286
diff
changeset
|
8 AC_REQUIRE([gl_BIGENDIAN]) |
18993
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
9 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
10 AC_CACHE_CHECK([where to find the exponent in a 'long double'], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
11 [gl_cv_cc_long_double_expbit0], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
12 [ |
13579
da9779900713
Modernize AC_TRY_RUN invocations.
Bruno Haible <bruno@clisp.org>
parents:
12559
diff
changeset
|
13 AC_RUN_IFELSE( |
da9779900713
Modernize AC_TRY_RUN invocations.
Bruno Haible <bruno@clisp.org>
parents:
12559
diff
changeset
|
14 [AC_LANG_SOURCE([[ |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
15 #include <float.h> |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
16 #include <stddef.h> |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
17 #include <stdio.h> |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
18 #include <string.h> |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
19 #define NWORDS \ |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
20 ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
21 typedef union { long double value; unsigned int word[NWORDS]; } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
22 memory_long_double; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
23 static unsigned int ored_words[NWORDS]; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
24 static unsigned int anded_words[NWORDS]; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
25 static void add_to_ored_words (long double x) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
26 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
27 memory_long_double m; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
28 size_t i; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
29 /* Clear it first, in case |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
30 sizeof (long double) < sizeof (memory_long_double). */ |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
31 memset (&m, 0, sizeof (memory_long_double)); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
32 m.value = x; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
33 for (i = 0; i < NWORDS; i++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
34 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
35 ored_words[i] |= m.word[i]; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
36 anded_words[i] &= m.word[i]; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
37 } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
38 } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
39 int main () |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
40 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
41 size_t j; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
42 FILE *fp = fopen ("conftest.out", "w"); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
43 if (fp == NULL) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
44 return 1; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
45 for (j = 0; j < NWORDS; j++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
46 anded_words[j] = ~ (unsigned int) 0; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
47 add_to_ored_words (0.25L); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
48 add_to_ored_words (0.5L); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
49 add_to_ored_words (1.0L); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
50 add_to_ored_words (2.0L); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
51 add_to_ored_words (4.0L); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
52 /* Remove bits that are common (e.g. if representation of the first mantissa |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
53 bit is explicit). */ |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
54 for (j = 0; j < NWORDS; j++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
55 ored_words[j] &= ~anded_words[j]; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
56 /* Now find the nonzero word. */ |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
57 for (j = 0; j < NWORDS; j++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
58 if (ored_words[j] != 0) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
59 break; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
60 if (j < NWORDS) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
61 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
62 size_t i; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
63 for (i = j + 1; i < NWORDS; i++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
64 if (ored_words[i] != 0) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
65 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
66 fprintf (fp, "unknown"); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
67 return (fclose (fp) != 0); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
68 } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
69 for (i = 0; ; i++) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
70 if ((ored_words[j] >> i) & 1) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
71 { |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
72 fprintf (fp, "word %d bit %d", (int) j, (int) i); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
73 return (fclose (fp) != 0); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
74 } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
75 } |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
76 fprintf (fp, "unknown"); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
77 return (fclose (fp) != 0); |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
78 } |
13579
da9779900713
Modernize AC_TRY_RUN invocations.
Bruno Haible <bruno@clisp.org>
parents:
12559
diff
changeset
|
79 ]])], |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
80 [gl_cv_cc_long_double_expbit0=`cat conftest.out`], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
81 [gl_cv_cc_long_double_expbit0="unknown"], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
82 [ |
18993
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
83 dnl When cross-compiling, in general we don't know. It depends on the |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
84 dnl ABI and compiler version. There are too many cases. |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
85 gl_cv_cc_long_double_expbit0="unknown" |
18993
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
86 case "$host_os" in |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
87 mingw*) # On native Windows (little-endian), we know the result |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
88 # in two cases: mingw, MSVC. |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
89 AC_EGREP_CPP([Known], [ |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
90 #ifdef __MINGW32__ |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
91 Known |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
92 #endif |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
93 ], [gl_cv_cc_long_double_expbit0="word 2 bit 0"]) |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
94 AC_EGREP_CPP([Known], [ |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
95 #ifdef _MSC_VER |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
96 Known |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
97 #endif |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
98 ], [gl_cv_cc_long_double_expbit0="word 1 bit 20"]) |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
99 ;; |
a75cfc731331
Improve cross-compilation guesses for native Windows.
Bruno Haible <bruno@clisp.org>
parents:
18626
diff
changeset
|
100 esac |
10286
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
101 ]) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
102 rm -f conftest.out |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
103 ]) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
104 case "$gl_cv_cc_long_double_expbit0" in |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
105 word*bit*) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
106 word=`echo "$gl_cv_cc_long_double_expbit0" | sed -e 's/word //' -e 's/ bit.*//'` |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
107 bit=`echo "$gl_cv_cc_long_double_expbit0" | sed -e 's/word.*bit //'` |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
108 AC_DEFINE_UNQUOTED([LDBL_EXPBIT0_WORD], [$word], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
109 [Define as the word index where to find the exponent of 'long double'.]) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
110 AC_DEFINE_UNQUOTED([LDBL_EXPBIT0_BIT], [$bit], |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
111 [Define as the bit index in the word where to find bit 0 of the exponent of 'long double'.]) |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
112 ;; |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
113 esac |
12944217dba7
Move macros for finding floating-point exponents into separate M4 files.
Ben Pfaff <blp@cs.stanford.edu>
parents:
diff
changeset
|
114 ]) |