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# Copyright (C) 2002-2004, 2006-2018 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
double_exponent_test = '''
#include <float.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#define NWORDS \
((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { double value; unsigned int word[NWORDS]; } memory_double;
static unsigned int ored_words[NWORDS];
static unsigned int anded_words[NWORDS];
static void add_to_ored_words (double x)
{
memory_double m;
size_t i;
/* Clear it first, in case sizeof (double) < sizeof (memory_double). */
memset (&m, 0, sizeof (memory_double));
m.value = x;
for (i = 0; i < NWORDS; i++)
{
ored_words[i] |= m.word[i];
anded_words[i] &= m.word[i];
}
}
int main ()
{
size_t j;
FILE *fp = stdout;
if (fp == NULL)
return 1;
for (j = 0; j < NWORDS; j++)
anded_words[j] = ~ (unsigned int) 0;
add_to_ored_words (0.25);
add_to_ored_words (0.5);
add_to_ored_words (1.0);
add_to_ored_words (2.0);
add_to_ored_words (4.0);
/* Remove bits that are common (e.g. if representation of the first mantissa
bit is explicit). */
for (j = 0; j < NWORDS; j++)
ored_words[j] &= ~anded_words[j];
/* Now find the nonzero word. */
for (j = 0; j < NWORDS; j++)
if (ored_words[j] != 0)
break;
if (j < NWORDS)
{
size_t i;
for (i = j + 1; i < NWORDS; i++)
if (ored_words[i] != 0)
{
fprintf (fp, "-1/-1");
return (fclose (fp) != 0);
}
for (i = 0; ; i++)
if ((ored_words[j] >> i) & 1)
{
fprintf (fp, "%d/%d", (int) j, (int) i);
return (fclose (fp) != 0);
}
}
fprintf (fp, "-1/-1");
return (fclose (fp) != 0);
}
'''
gl_cv_cc_double_expbit0_word = -1
gl_cv_cc_double_expbit0_bit = -1
if meson.can_run_host_binaries()
run_result = cc.run(double_exponent_test,
name : 'where to find the exponent in a \'double\'')
if run_result.compiled() and run_result.returncode() == 0
out = run_result.stdout ().split ('/')
if out.length () == 2
gl_cv_cc_double_expbit0_word = out[0].to_int ()
gl_cv_cc_double_expbit0_bit = out[1].to_int ()
endif
endif
else
# On ARM, there are two 'double' floating-point formats, used by
# different sets of instructions: The older FPA instructions assume
# that they are stored in big-endian word order, while the words
# (like integer types) are stored in little-endian byte order.
# The newer VFP instructions assume little-endian order
# consistently.
if (cc.get_define ('arm') == '' and
cc.get_define ('__arm') == '' and
cc.get_define ('__arm__') == '')
gl_cv_cc_double_expbit0_bit = 20
if host_machine.endian () == 'big'
gl_cv_cc_double_expbit0_word = 0
else
gl_cv_cc_double_expbit0_word = 1
endif
endif
endif
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