zig/lib/libc/mingw/math/signbit.c

36 lines
937 B
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.
*/
#define __FP_SIGNBIT 0x0200
int __signbit (double x);
typedef union __mingw_dbl_type_t {
double x;
unsigned long long val;
__extension__ struct {
unsigned int low, high;
} lh;
} __mingw_dbl_type_t;
int __signbit (double x)
{
#if defined(__x86_64__) || defined(_AMD64_) || defined(__arm__) || defined(_ARM_) || defined(__aarch64__) || defined(_ARM64_)
__mingw_dbl_type_t hlp;
hlp.x = x;
return ((hlp.lh.high & 0x80000000) != 0);
#elif defined(__i386__) || defined(_X86_)
unsigned short sw;
__asm__ __volatile__ ("fxam; fstsw %%ax;"
: "=a" (sw)
: "t" (x) );
return (sw & __FP_SIGNBIT) != 0;
#endif
}
#undef signbit
int __attribute__ ((alias ("__signbit"))) signbit (double);