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/*
* Written by Michael Shalayeff. Public Domain
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$OpenBSD: s_trunc.c,v 1.1 2009/07/15 20:08:43 martynas Exp $";
#endif
#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(%1)" : "=m" (ofpsr) : "r" (&ofpsr));
fpsr = (ofpsr & ~((u_int64_t)FP_RM << (9 + 32))) |
((u_int64_t)FP_RZ << (9 + 32));
__asm__ __volatile__("fldds 0(%0), %%fr0" :: "r" (&fpsr));
__asm__ __volatile__("frnd,dbl %0,%0" : "+f" (x));
__asm__ __volatile__("fldds 0(%0), %%fr0" :: "r" (&ofpsr));
return (x);
}
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