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/* $OpenBSD: s_trunc.c,v 1.8 2016/09/12 19:47:02 guenther Exp $ */
/*
* Written by Michael Shalayeff. Public Domain
*/
#include <sys/types.h>
#include <machine/ieeefp.h>
#include "math.h"
double
trunc(double x)
{
u_int64_t ofpsr, fpsr;
__asm__ volatile("fstds %%fr0,0(%0)" :: "r" (&ofpsr) : "memory");
fpsr = (ofpsr & ~((u_int64_t)FP_RM << (9 + 32))) |
((u_int64_t)FP_RZ << (9 + 32));
__asm__ volatile("fldds 0(%0), %%fr0" :: "r" (&fpsr) : "memory");
__asm__ volatile("frnd,dbl %0,%0" : "+f" (x));
__asm__ volatile("fldds 0(%0), %%fr0" :: "r" (&ofpsr) : "memory");
return (x);
}
DEF_STD(trunc);
LDBL_UNUSED_CLONE(trunc);
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