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/**
* 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>
/* Mask and shift amount for rounding bits on x86/x86_64. */
#define FE_CW_ROUND_MASK (0x0c00)
#define FE_CW_ROUND_SHIFT (10)
long double
truncl (long double _x)
{
#if defined(_ARM_) || defined(__arm__)
return trunc(_x);
#else
long double retval = 0.0L;
unsigned short saved_cw;
unsigned short tmp_cw;
__asm__ __volatile__ ("fnstcw %0;" : "=m" (saved_cw)); /* save FPU control word */
tmp_cw = (saved_cw & ~FE_CW_ROUND_MASK)
| (FE_TOWARDZERO << FE_CW_ROUND_SHIFT);
__asm__ __volatile__ ("fldcw %0;" : : "m" (tmp_cw));
__asm__ __volatile__ ("frndint;" : "=t" (retval) : "0" (_x)); /* round towards zero */
__asm__ __volatile__ ("fldcw %0;" : : "m" (saved_cw) ); /* restore saved control word */
return retval;
#endif /* defined(_ARM_) || defined(__arm__) */
}
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