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Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/log1pf.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/log1pf.c77
1 files changed, 0 insertions, 77 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/log1pf.c b/lib/mlibc/options/ansi/musl-generic-math/log1pf.c
deleted file mode 100644
index 23985c3..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/log1pf.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/s_log1pf.c */
-/*
- * ====================================================
- * 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.
- * ====================================================
- */
-
-#include "libm.h"
-
-static const float
-ln2_hi = 6.9313812256e-01, /* 0x3f317180 */
-ln2_lo = 9.0580006145e-06, /* 0x3717f7d1 */
-/* |(log(1+s)-log(1-s))/s - Lg(s)| < 2**-34.24 (~[-4.95e-11, 4.97e-11]). */
-Lg1 = 0xaaaaaa.0p-24, /* 0.66666662693 */
-Lg2 = 0xccce13.0p-25, /* 0.40000972152 */
-Lg3 = 0x91e9ee.0p-25, /* 0.28498786688 */
-Lg4 = 0xf89e26.0p-26; /* 0.24279078841 */
-
-float log1pf(float x)
-{
- union {float f; uint32_t i;} u = {x};
- float_t hfsq,f,c,s,z,R,w,t1,t2,dk;
- uint32_t ix,iu;
- int k;
-
- ix = u.i;
- k = 1;
- if (ix < 0x3ed413d0 || ix>>31) { /* 1+x < sqrt(2)+ */
- if (ix >= 0xbf800000) { /* x <= -1.0 */
- if (x == -1)
- return x/0.0f; /* log1p(-1)=+inf */
- return (x-x)/0.0f; /* log1p(x<-1)=NaN */
- }
- if (ix<<1 < 0x33800000<<1) { /* |x| < 2**-24 */
- /* underflow if subnormal */
- if ((ix&0x7f800000) == 0)
- FORCE_EVAL(x*x);
- return x;
- }
- if (ix <= 0xbe95f619) { /* sqrt(2)/2- <= 1+x < sqrt(2)+ */
- k = 0;
- c = 0;
- f = x;
- }
- } else if (ix >= 0x7f800000)
- return x;
- if (k) {
- u.f = 1 + x;
- iu = u.i;
- iu += 0x3f800000 - 0x3f3504f3;
- k = (int)(iu>>23) - 0x7f;
- /* correction term ~ log(1+x)-log(u), avoid underflow in c/u */
- if (k < 25) {
- c = k >= 2 ? 1-(u.f-x) : x-(u.f-1);
- c /= u.f;
- } else
- c = 0;
- /* reduce u into [sqrt(2)/2, sqrt(2)] */
- iu = (iu&0x007fffff) + 0x3f3504f3;
- u.i = iu;
- f = u.f - 1;
- }
- s = f/(2.0f + f);
- z = s*s;
- w = z*z;
- t1= w*(Lg2+w*Lg4);
- t2= z*(Lg1+w*Lg3);
- R = t2 + t1;
- hfsq = 0.5f*f*f;
- dk = k;
- return s*(hfsq+R) + (dk*ln2_lo+c) - hfsq + f + dk*ln2_hi;
-}