X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=blobdiff_plain;f=src%2Fmath%2Fcoshf.c;h=b09f2ee5751f4341cfb6cc759055279deda1d7cb;hp=97318f1098203109986f61483ff3ac211d1590c8;hb=6a4cfbdbe718a115a22629ad0cb2ae21391a0454;hpb=0cbb65479147ecdaa664e88cc2a5a925f3de502f

diff --git a/src/math/coshf.c b/src/math/coshf.c
index 97318f10..b09f2ee5 100644
--- a/src/math/coshf.c
+++ b/src/math/coshf.c
@@ -1,57 +1,33 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/e_coshf.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.
- * ====================================================
- */
-
 #include "libm.h"
 
-static const float huge = 1.0e30;
-
 float coshf(float x)
 {
-	float t, w;
-	int32_t ix;
-
-	GET_FLOAT_WORD(ix, x);
-	ix &= 0x7fffffff;
-
-	/* x is INF or NaN */
-	if (ix >= 0x7f800000)
-		return x*x;
-
-	/* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */
-	if (ix < 0x3eb17218) {
-		t = expm1f(fabsf(x));
-		w = 1.0f+t;
-		if (ix<0x39800000)
-			return 1.0f;  /* cosh(tiny) = 1 */
-		return 1.0f + (t*t)/(w+w);
+	union {float f; uint32_t i;} u = {.f = x};
+	uint32_t w;
+	float t;
+
+	/* |x| */
+	u.i &= 0x7fffffff;
+	x = u.f;
+	w = u.i;
+
+	/* |x| < log(2) */
+	if (w < 0x3f317217) {
+		if (w < 0x3f800000 - (12<<23)) {
+			FORCE_EVAL(x + 0x1p120f);
+			return 1;
+		}
+		t = expm1f(x);
+		return 1 + t*t/(2*(1+t));
 	}
 
-	/* |x| in [0.5*ln2,9], return (exp(|x|)+1/exp(|x|))/2; */
-	if (ix < 0x41100000) {
-		t = expf(fabsf(x));
-		return 0.5f*t + 0.5f/t;
+	/* |x| < log(FLT_MAX) */
+	if (w < 0x42b17217) {
+		t = expf(x);
+		return 0.5f*(t + 1/t);
 	}
 
-	/* |x| in [9, log(maxfloat)] return 0.5f*exp(|x|) */
-	if (ix < 0x42b17217)
-		return 0.5f*expf(fabsf(x));
-
-	/* |x| in [log(maxfloat), overflowthresold] */
-	if (ix <= 0x42b2d4fc)
-		return __expo2f(fabsf(x));
-
-	/* |x| > overflowthresold, cosh(x) overflow */
-	return huge*huge;
+	/* |x| > log(FLT_MAX) or nan */
+	t = __expo2f(x);
+	return t;
 }