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/* $OpenBSD: e_sqrt.c,v 1.7 2016/09/12 19:47:02 guenther Exp $ */
/*
* Written by Martynas Venckus. Public domain
*/
#include <sys/types.h>
#include <math.h>
#define FPSCR_PR (1 << 19)
#define FPSCR_SZ (1 << 20)
double
sqrt(double d)
{
register_t fpscr, nfpscr;
__asm__ volatile ("sts fpscr, %0" : "=r" (fpscr));
/* Set floating-point mode to double-precision. */
nfpscr = fpscr | FPSCR_PR;
/* Do not set SZ and PR to 1 simultaneously. */
nfpscr &= ~FPSCR_SZ;
__asm__ volatile ("lds %0, fpscr" : : "r" (nfpscr));
__asm__ volatile ("fsqrt %0" : "+f" (d));
/* Restore fp status/control register. */
__asm__ volatile ("lds %0, fpscr" : : "r" (fpscr));
return (d);
}
DEF_STD(sqrt);
LDBL_CLONE(sqrt);
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