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authorUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
committerUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
commitabfbdde177c3a7155070dda1b2cdc8292054cc26 (patch)
treee021306b596381fbf8311d2b7eb294e918ff17c8 /sysdeps/ieee754/flt-32/e_lgammaf_r.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
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Update.
Diffstat (limited to 'sysdeps/ieee754/flt-32/e_lgammaf_r.c')
-rw-r--r--sysdeps/ieee754/flt-32/e_lgammaf_r.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/sysdeps/ieee754/flt-32/e_lgammaf_r.c b/sysdeps/ieee754/flt-32/e_lgammaf_r.c
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+++ b/sysdeps/ieee754/flt-32/e_lgammaf_r.c
@@ -0,0 +1,250 @@
+/* e_lgammaf_r.c -- float version of e_lgamma_r.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_lgammaf_r.c,v 1.3 1995/05/10 20:45:47 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const float
+#else
+static float
+#endif
+two23=  8.3886080000e+06, /* 0x4b000000 */
+half=  5.0000000000e-01, /* 0x3f000000 */
+one =  1.0000000000e+00, /* 0x3f800000 */
+pi  =  3.1415927410e+00, /* 0x40490fdb */
+a0  =  7.7215664089e-02, /* 0x3d9e233f */
+a1  =  3.2246702909e-01, /* 0x3ea51a66 */
+a2  =  6.7352302372e-02, /* 0x3d89f001 */
+a3  =  2.0580807701e-02, /* 0x3ca89915 */
+a4  =  7.3855509982e-03, /* 0x3bf2027e */
+a5  =  2.8905137442e-03, /* 0x3b3d6ec6 */
+a6  =  1.1927076848e-03, /* 0x3a9c54a1 */
+a7  =  5.1006977446e-04, /* 0x3a05b634 */
+a8  =  2.2086278477e-04, /* 0x39679767 */
+a9  =  1.0801156895e-04, /* 0x38e28445 */
+a10 =  2.5214456400e-05, /* 0x37d383a2 */
+a11 =  4.4864096708e-05, /* 0x383c2c75 */
+tc  =  1.4616321325e+00, /* 0x3fbb16c3 */
+tf  = -1.2148628384e-01, /* 0xbdf8cdcd */
+/* tt = -(tail of tf) */
+tt  =  6.6971006518e-09, /* 0x31e61c52 */
+t0  =  4.8383611441e-01, /* 0x3ef7b95e */
+t1  = -1.4758771658e-01, /* 0xbe17213c */
+t2  =  6.4624942839e-02, /* 0x3d845a15 */
+t3  = -3.2788541168e-02, /* 0xbd064d47 */
+t4  =  1.7970675603e-02, /* 0x3c93373d */
+t5  = -1.0314224288e-02, /* 0xbc28fcfe */
+t6  =  6.1005386524e-03, /* 0x3bc7e707 */
+t7  = -3.6845202558e-03, /* 0xbb7177fe */
+t8  =  2.2596477065e-03, /* 0x3b141699 */
+t9  = -1.4034647029e-03, /* 0xbab7f476 */
+t10 =  8.8108185446e-04, /* 0x3a66f867 */
+t11 = -5.3859531181e-04, /* 0xba0d3085 */
+t12 =  3.1563205994e-04, /* 0x39a57b6b */
+t13 = -3.1275415677e-04, /* 0xb9a3f927 */
+t14 =  3.3552918467e-04, /* 0x39afe9f7 */
+u0  = -7.7215664089e-02, /* 0xbd9e233f */
+u1  =  6.3282704353e-01, /* 0x3f2200f4 */
+u2  =  1.4549225569e+00, /* 0x3fba3ae7 */
+u3  =  9.7771751881e-01, /* 0x3f7a4bb2 */
+u4  =  2.2896373272e-01, /* 0x3e6a7578 */
+u5  =  1.3381091878e-02, /* 0x3c5b3c5e */
+v1  =  2.4559779167e+00, /* 0x401d2ebe */
+v2  =  2.1284897327e+00, /* 0x4008392d */
+v3  =  7.6928514242e-01, /* 0x3f44efdf */
+v4  =  1.0422264785e-01, /* 0x3dd572af */
+v5  =  3.2170924824e-03, /* 0x3b52d5db */
+s0  = -7.7215664089e-02, /* 0xbd9e233f */
+s1  =  2.1498242021e-01, /* 0x3e5c245a */
+s2  =  3.2577878237e-01, /* 0x3ea6cc7a */
+s3  =  1.4635047317e-01, /* 0x3e15dce6 */
+s4  =  2.6642270386e-02, /* 0x3cda40e4 */
+s5  =  1.8402845599e-03, /* 0x3af135b4 */
+s6  =  3.1947532989e-05, /* 0x3805ff67 */
+r1  =  1.3920053244e+00, /* 0x3fb22d3b */
+r2  =  7.2193557024e-01, /* 0x3f38d0c5 */
+r3  =  1.7193385959e-01, /* 0x3e300f6e */
+r4  =  1.8645919859e-02, /* 0x3c98bf54 */
+r5  =  7.7794247773e-04, /* 0x3a4beed6 */
+r6  =  7.3266842264e-06, /* 0x36f5d7bd */
+w0  =  4.1893854737e-01, /* 0x3ed67f1d */
+w1  =  8.3333335817e-02, /* 0x3daaaaab */
+w2  = -2.7777778450e-03, /* 0xbb360b61 */
+w3  =  7.9365057172e-04, /* 0x3a500cfd */
+w4  = -5.9518753551e-04, /* 0xba1c065c */
+w5  =  8.3633989561e-04, /* 0x3a5b3dd2 */
+w6  = -1.6309292987e-03; /* 0xbad5c4e8 */
+
+#ifdef __STDC__
+static const float zero=  0.0000000000e+00;
+#else
+static float zero=  0.0000000000e+00;
+#endif
+
+#ifdef __STDC__
+	static float sin_pif(float x)
+#else
+	static float sin_pif(x)
+	float x;
+#endif
+{
+	float y,z;
+	int n,ix;
+
+	GET_FLOAT_WORD(ix,x);
+	ix &= 0x7fffffff;
+
+	if(ix<0x3e800000) return __kernel_sinf(pi*x,zero,0);
+	y = -x;		/* x is assume negative */
+
+    /*
+     * argument reduction, make sure inexact flag not raised if input
+     * is an integer
+     */
+	z = __floorf(y);
+	if(z!=y) {				/* inexact anyway */
+	    y  *= (float)0.5;
+	    y   = (float)2.0*(y - __floorf(y));	/* y = |x| mod 2.0 */
+	    n   = (int) (y*(float)4.0);
+	} else {
+            if(ix>=0x4b800000) {
+                y = zero; n = 0;                 /* y must be even */
+            } else {
+                if(ix<0x4b000000) z = y+two23;	/* exact */
+		GET_FLOAT_WORD(n,z);
+		n &= 1;
+                y  = n;
+                n<<= 2;
+            }
+        }
+	switch (n) {
+	    case 0:   y =  __kernel_sinf(pi*y,zero,0); break;
+	    case 1:
+	    case 2:   y =  __kernel_cosf(pi*((float)0.5-y),zero); break;
+	    case 3:
+	    case 4:   y =  __kernel_sinf(pi*(one-y),zero,0); break;
+	    case 5:
+	    case 6:   y = -__kernel_cosf(pi*(y-(float)1.5),zero); break;
+	    default:  y =  __kernel_sinf(pi*(y-(float)2.0),zero,0); break;
+	    }
+	return -y;
+}
+
+
+#ifdef __STDC__
+	float __ieee754_lgammaf_r(float x, int *signgamp)
+#else
+	float __ieee754_lgammaf_r(x,signgamp)
+	float x; int *signgamp;
+#endif
+{
+	float t,y,z,nadj,p,p1,p2,p3,q,r,w;
+	int i,hx,ix;
+
+	GET_FLOAT_WORD(hx,x);
+
+    /* purge off +-inf, NaN, +-0, and negative arguments */
+	*signgamp = 1;
+	if ((unsigned int)hx==0xff800000)
+	  return x-x;
+	ix = hx&0x7fffffff;
+	if(ix>=0x7f800000) return x*x;
+	if(ix==0) return one/fabsf(x);
+	if(ix<0x1c800000) {	/* |x|<2**-70, return -log(|x|) */
+	    if(hx<0) {
+	        *signgamp = -1;
+	        return -__ieee754_logf(-x);
+	    } else return -__ieee754_logf(x);
+	}
+	if(hx<0) {
+	    if(ix>=0x4b000000) 	/* |x|>=2**23, must be -integer */
+		return x/zero;
+	    t = sin_pif(x);
+	    if(t==zero) return one/fabsf(t); /* -integer */
+	    nadj = __ieee754_logf(pi/fabsf(t*x));
+	    if(t<zero) *signgamp = -1;
+	    x = -x;
+	}
+
+    /* purge off 1 and 2 */
+	if (ix==0x3f800000||ix==0x40000000) r = 0;
+    /* for x < 2.0 */
+	else if(ix<0x40000000) {
+	    if(ix<=0x3f666666) { 	/* lgamma(x) = lgamma(x+1)-log(x) */
+		r = -__ieee754_logf(x);
+		if(ix>=0x3f3b4a20) {y = one-x; i= 0;}
+		else if(ix>=0x3e6d3308) {y= x-(tc-one); i=1;}
+	  	else {y = x; i=2;}
+	    } else {
+	  	r = zero;
+	        if(ix>=0x3fdda618) {y=(float)2.0-x;i=0;} /* [1.7316,2] */
+	        else if(ix>=0x3F9da620) {y=x-tc;i=1;} /* [1.23,1.73] */
+		else {y=x-one;i=2;}
+	    }
+	    switch(i) {
+	      case 0:
+		z = y*y;
+		p1 = a0+z*(a2+z*(a4+z*(a6+z*(a8+z*a10))));
+		p2 = z*(a1+z*(a3+z*(a5+z*(a7+z*(a9+z*a11)))));
+		p  = y*p1+p2;
+		r  += (p-(float)0.5*y); break;
+	      case 1:
+		z = y*y;
+		w = z*y;
+		p1 = t0+w*(t3+w*(t6+w*(t9 +w*t12)));	/* parallel comp */
+		p2 = t1+w*(t4+w*(t7+w*(t10+w*t13)));
+		p3 = t2+w*(t5+w*(t8+w*(t11+w*t14)));
+		p  = z*p1-(tt-w*(p2+y*p3));
+		r += (tf + p); break;
+	      case 2:
+		p1 = y*(u0+y*(u1+y*(u2+y*(u3+y*(u4+y*u5)))));
+		p2 = one+y*(v1+y*(v2+y*(v3+y*(v4+y*v5))));
+		r += (-(float)0.5*y + p1/p2);
+	    }
+	}
+	else if(ix<0x41000000) { 			/* x < 8.0 */
+	    i = (int)x;
+	    t = zero;
+	    y = x-(float)i;
+	    p = y*(s0+y*(s1+y*(s2+y*(s3+y*(s4+y*(s5+y*s6))))));
+	    q = one+y*(r1+y*(r2+y*(r3+y*(r4+y*(r5+y*r6)))));
+	    r = half*y+p/q;
+	    z = one;	/* lgamma(1+s) = log(s) + lgamma(s) */
+	    switch(i) {
+	    case 7: z *= (y+(float)6.0);	/* FALLTHRU */
+	    case 6: z *= (y+(float)5.0);	/* FALLTHRU */
+	    case 5: z *= (y+(float)4.0);	/* FALLTHRU */
+	    case 4: z *= (y+(float)3.0);	/* FALLTHRU */
+	    case 3: z *= (y+(float)2.0);	/* FALLTHRU */
+		    r += __ieee754_logf(z); break;
+	    }
+    /* 8.0 <= x < 2**58 */
+	} else if (ix < 0x5c800000) {
+	    t = __ieee754_logf(x);
+	    z = one/x;
+	    y = z*z;
+	    w = w0+z*(w1+y*(w2+y*(w3+y*(w4+y*(w5+y*w6)))));
+	    r = (x-half)*(t-one)+w;
+	} else
+    /* 2**58 <= x <= inf */
+	    r =  x*(__ieee754_logf(x)-one);
+	if(hx<0) r = nadj - r;
+	return r;
+}