gcc/libgcc-math/flt-32/e_sqrtf.c
Richard Guenther 6ff68ac318 re PR bootstrap/26055 (libgcc-math declaration of __isinf conflicts with system header, fails bootstrap)
2006-02-28  Richard Guenther  <rguenther@suse.de>

	PR bootstrap/26055
	Revert
	* configure.ac: Disable libgcc-math if we cannot mix
	declaration of __isinf and math.h inclusion.
	* configure: Re-generate.

	* i386/Makefile.am: Use -std=c99, do not use -ffinite-math-only,
	do not define __NO_MATH_INLINES.
	* i386/Makefile.in: Re-generate.
	* include/math_private.h (__atanf): Declare.
	(__scalbnf): Likewise.
	(__floorf): Likewise.
	(__isinff): Likewise.
	(__scalbn): Likewise.
	(__floor): Likewise.
	(fabs): Likewise.
	(fabsf): Likewise.
	* flt-32/e_acosf.c: Do not include math.h
	* flt-32/s_isinff.c: Likewise.
	* flt-32/k_tanf.c: Likewise.
	* flt-32/e_sqrtf.c: Likewise.
	* flt-32/e_asinf.c: Likewise.
	* flt-32/k_cosf.c: Likewise.
	* flt-32/k_sinf.c: Likewise.
	* flt-32/s_floorf.c: Likewise.
	* flt-32/s_tanf.c: Likewise.
	* flt-32/s_atanf.c: Likewise.
	* flt-32/s_cosf.c: Likewise.
	* flt-32/e_atan2f.c: Likewise.
	* flt-32/e_powf.c: Likewise.
	* flt-32/s_sinf.c: Likewise.
	* flt-32/e_rem_pio2f.c: Likewise.
	* flt-32/s_scalbnf.c: Likewise.
	* flt-32/e_logf.c: Likewise.
	* flt-32/e_log10f.c: Likewise.
	* flt-32/k_rem_pio2f.c: Likewise.
	* flt-32/e_expf.c: Likewise.  Use __builtin_isless and
	__builtin_isgreater.
	* dbl-64/s_floor.c: Do not include math.h.
	* dbl-64/e_log10.c: Likewise.
	* dbl-64/k_rem_pio2.c: Likewise.
	* dbl-64/s_atan.c: Likewise.
	* dbl-64/s_scalbn.c: Likewise.
	* dbl-64/s_isinf.c: Likewise.
	* dbl-64/s_tan.c: Likewise.
	* dbl-64/e_rem_pio2.c: Likewise.  Avoid uninitialized variable
	warning.
	* dbl-64/mpa.c: Likewise.

From-SVN: r111563
2006-02-28 11:29:41 +00:00

97 lines
2.1 KiB
C

/* e_sqrtf.c -- float version of e_sqrt.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: e_sqrtf.c,v 1.4 1995/05/10 20:46:19 jtc Exp $";
#endif
#include "math_private.h"
#ifdef __STDC__
static const float one = 1.0, tiny=1.0e-30;
#else
static float one = 1.0, tiny=1.0e-30;
#endif
#ifdef __STDC__
float __ieee754_sqrtf(float x)
#else
float __ieee754_sqrtf(x)
float x;
#endif
{
float z;
int32_t sign = (int)0x80000000;
int32_t ix,s,q,m,t,i;
uint32_t r;
GET_FLOAT_WORD(ix,x);
/* take care of Inf and NaN */
if((ix&0x7f800000)==0x7f800000) {
return x*x+x; /* sqrt(NaN)=NaN, sqrt(+inf)=+inf
sqrt(-inf)=sNaN */
}
/* take care of zero */
if(ix<=0) {
if((ix&(~sign))==0) return x;/* sqrt(+-0) = +-0 */
else if(ix<0)
return (x-x)/(x-x); /* sqrt(-ve) = sNaN */
}
/* normalize x */
m = (ix>>23);
if(m==0) { /* subnormal x */
for(i=0;(ix&0x00800000)==0;i++) ix<<=1;
m -= i-1;
}
m -= 127; /* unbias exponent */
ix = (ix&0x007fffff)|0x00800000;
if(m&1) /* odd m, double x to make it even */
ix += ix;
m >>= 1; /* m = [m/2] */
/* generate sqrt(x) bit by bit */
ix += ix;
q = s = 0; /* q = sqrt(x) */
r = 0x01000000; /* r = moving bit from right to left */
while(r!=0) {
t = s+r;
if(t<=ix) {
s = t+r;
ix -= t;
q += r;
}
ix += ix;
r>>=1;
}
/* use floating add to find out rounding direction */
if(ix!=0) {
z = one-tiny; /* trigger inexact flag */
if (z>=one) {
z = one+tiny;
if (z>one)
q += 2;
else
q += (q&1);
}
}
ix = (q>>1)+0x3f000000;
ix += (m <<23);
SET_FLOAT_WORD(z,ix);
return z;
}