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-rw-r--r--sysdeps/ieee754/dbl-64/e_acos.c145
1 files changed, 1 insertions, 144 deletions
diff --git a/sysdeps/ieee754/dbl-64/e_acos.c b/sysdeps/ieee754/dbl-64/e_acos.c
index eb4080a8b8..8f7cd89249 100644
--- a/sysdeps/ieee754/dbl-64/e_acos.c
+++ b/sysdeps/ieee754/dbl-64/e_acos.c
@@ -1,144 +1 @@
-/* @(#)e_acos.c 5.1 93/09/24 */
-/*
- * ====================================================
- * 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.
- * ====================================================
- */
-/* Modified by Naohiko Shimizu/Tokai University, Japan 1997/08/25,
-   for performance improvement on pipelined processors.
- */
-
-#if defined(LIBM_SCCS) && !defined(lint)
-static char rcsid[] = "$NetBSD: e_acos.c,v 1.9 1995/05/12 04:57:13 jtc Exp $";
-#endif
-
-/* __ieee754_acos(x)
- * Method :
- *	acos(x)  = pi/2 - asin(x)
- *	acos(-x) = pi/2 + asin(x)
- * For |x|<=0.5
- *	acos(x) = pi/2 - (x + x*x^2*R(x^2))	(see asin.c)
- * For x>0.5
- * 	acos(x) = pi/2 - (pi/2 - 2asin(sqrt((1-x)/2)))
- *		= 2asin(sqrt((1-x)/2))
- *		= 2s + 2s*z*R(z) 	...z=(1-x)/2, s=sqrt(z)
- *		= 2f + (2c + 2s*z*R(z))
- *     where f=hi part of s, and c = (z-f*f)/(s+f) is the correction term
- *     for f so that f+c ~ sqrt(z).
- * For x<-0.5
- *	acos(x) = pi - 2asin(sqrt((1-|x|)/2))
- *		= pi - 0.5*(s+s*z*R(z)), where z=(1-|x|)/2,s=sqrt(z)
- *
- * Special cases:
- *	if x is NaN, return x itself;
- *	if |x|>1, return NaN with invalid signal.
- *
- * Function needed: __ieee754_sqrt
- */
-
-#include "math.h"
-#include "math_private.h"
-#define one qS[0]
-
-#ifdef __STDC__
-static const double
-#else
-static double
-#endif
-pi =  3.14159265358979311600e+00, /* 0x400921FB, 0x54442D18 */
-pio2_hi =  1.57079632679489655800e+00, /* 0x3FF921FB, 0x54442D18 */
-pio2_lo =  6.12323399573676603587e-17, /* 0x3C91A626, 0x33145C07 */
-pS[] =  {1.66666666666666657415e-01, /* 0x3FC55555, 0x55555555 */
- -3.25565818622400915405e-01, /* 0xBFD4D612, 0x03EB6F7D */
-  2.01212532134862925881e-01, /* 0x3FC9C155, 0x0E884455 */
- -4.00555345006794114027e-02, /* 0xBFA48228, 0xB5688F3B */
-  7.91534994289814532176e-04, /* 0x3F49EFE0, 0x7501B288 */
-  3.47933107596021167570e-05}, /* 0x3F023DE1, 0x0DFDF709 */
-qS[] ={1.0, -2.40339491173441421878e+00, /* 0xC0033A27, 0x1C8A2D4B */
-  2.02094576023350569471e+00, /* 0x40002AE5, 0x9C598AC8 */
- -6.88283971605453293030e-01, /* 0xBFE6066C, 0x1B8D0159 */
-  7.70381505559019352791e-02}; /* 0x3FB3B8C5, 0xB12E9282 */
-
-#ifdef __STDC__
-	double __ieee754_acos(double x)
-#else
-	double __ieee754_acos(x)
-	double x;
-#endif
-{
-	double z,p,q,r,w,s,c,df,p1,p2,p3,q1,q2,z2,z4,z6;
-	int32_t hx,ix;
-	GET_HIGH_WORD(hx,x);
-	ix = hx&0x7fffffff;
-	if(ix>=0x3ff00000) {	/* |x| >= 1 */
-	    u_int32_t lx;
-	    GET_LOW_WORD(lx,x);
-	    if(((ix-0x3ff00000)|lx)==0) {	/* |x|==1 */
-		if(hx>0) return 0.0;		/* acos(1) = 0  */
-		else return pi+2.0*pio2_lo;	/* acos(-1)= pi */
-	    }
-	    return (x-x)/(x-x);		/* acos(|x|>1) is NaN */
-	}
-	if(ix<0x3fe00000) {	/* |x| < 0.5 */
-	    if(ix<=0x3c600000) return pio2_hi+pio2_lo;/*if|x|<2**-57*/
-	    z = x*x;
-#ifdef DO_NOT_USE_THIS
-	    p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*pS5)))));
-	    q = one+z*(qS1+z*(qS2+z*(qS3+z*qS4)));
-#else
- 	    p1 = z*pS[0]; z2=z*z;
- 	    p2 = pS[1]+z*pS[2]; z4=z2*z2;
- 	    p3 = pS[3]+z*pS[4]; z6=z4*z2;
- 	    q1 = one+z*qS[1];
- 	    q2 = qS[2]+z*qS[3];
- 	    p = p1 + z2*p2 + z4*p3 + z6*pS[5];
- 	    q = q1 + z2*q2 + z4*qS[4];
-#endif
-	    r = p/q;
-	    return pio2_hi - (x - (pio2_lo-x*r));
-	} else  if (hx<0) {		/* x < -0.5 */
-	    z = (one+x)*0.5;
-#ifdef DO_NOT_USE_THIS
-	    p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*pS5)))));
-	    q = one+z*(qS1+z*(qS2+z*(qS3+z*qS4)));
-#else
-	    p1 = z*pS[0]; z2=z*z;
-	    p2 = pS[1]+z*pS[2]; z4=z2*z2;
-	    p3 = pS[3]+z*pS[4]; z6=z4*z2;
-	    q1 = one+z*qS[1];
-	    q2 = qS[2]+z*qS[3];
-	    p = p1 + z2*p2 + z4*p3 + z6*pS[5];
-	    q = q1 + z2*q2 + z4*qS[4];
-#endif
-	    s = __ieee754_sqrt(z);
-	    r = p/q;
-	    w = r*s-pio2_lo;
-	    return pi - 2.0*(s+w);
-	} else {			/* x > 0.5 */
-	    z = (one-x)*0.5;
-	    s = __ieee754_sqrt(z);
-	    df = s;
-	    SET_LOW_WORD(df,0);
-	    c  = (z-df*df)/(s+df);
-#ifdef DO_NOT_USE_THIS
-	    p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*pS5)))));
-	    q = one+z*(qS1+z*(qS2+z*(qS3+z*qS4)));
-#else
-	    p1 = z*pS[0]; z2=z*z;
-	    p2 = pS[1]+z*pS[2]; z4=z2*z2;
-	    p3 = pS[3]+z*pS[4]; z6=z4*z2;
-	    q1 = one+z*qS[1];
-	    q2 = qS[2]+z*qS[3];
-	    p = p1 + z2*p2 + z4*p3 + z6*pS[5];
-	    q = q1 + z2*q2 + z4*qS[4];
-#endif
-	    r = p/q;
-	    w = r*s+c;
-	    return 2.0*(df+w);
-	}
-}
+/* In e_asin.c */