newlib-cygwin/winsup/cygwin/math/modfl.c

42 lines
1.1 KiB
C

/**
* This file has no copyright assigned and is placed in the Public Domain.
* This file is part of the mingw-w64 runtime package.
* No warranty is given; refer to the file DISCLAIMER.PD within this package.
*/
#include <fenv.h>
#include <math.h>
#include <errno.h>
long double
modfl (long double value, long double* iptr)
{
long double int_part = 0.0L;
/* truncate */
#if defined(_AMD64_) || defined(__x86_64__)
asm ("subq $8, %%rsp\n"
"fnstcw 4(%%rsp)\n"
"movzwl 4(%%rsp), %%eax\n"
"orb $12, %%ah\n"
"movw %%ax, (%%rsp)\n"
"fldcw (%%rsp)\n"
"frndint\n"
"fldcw 4(%%rsp)\n"
"addq $8, %%rsp\n" : "=t" (int_part) : "0" (value)); /* round */
#elif defined(_X86_) || defined(__i386__)
asm ("push %%eax\n\tsubl $8, %%esp\n"
"fnstcw 4(%%esp)\n"
"movzwl 4(%%esp), %%eax\n"
"orb $12, %%ah\n"
"movw %%ax, (%%esp)\n"
"fldcw (%%esp)\n"
"frndint\n"
"fldcw 4(%%esp)\n"
"addl $8, %%esp\n\tpop %%eax\n" : "=t" (int_part) : "0" (value)); /* round */
#else
int_part = truncl(value);
#endif
if (iptr)
*iptr = int_part;
return (isinf (value) ? 0.0L : value - int_part);
}