Optimize libm

libm is now somewhat integrated with gcc's -ffinite-math-only option
and lots of the wrapper functions have been optimized.

1 files changed, 60 insertions, 62 deletions

diff --git a/math/w_powf.c b/math/w_powf.c
index 761e4d1328..c0406f4c12 100644
--- a/math/w_powf.c
+++ b/math/w_powf.c
@@ -1,77 +1,75 @@
-/* w_powf.c -- float version of w_pow.c.
- * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
- */
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
 
-/*
- * ====================================================
- * 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.
- * ====================================================
- */
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
 
-#if defined(LIBM_SCCS) && !defined(lint)
-static char rcsid[] = "$NetBSD: w_powf.c,v 1.3 1995/05/10 20:49:41 jtc Exp $";
-#endif
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
 
-/*
- * wrapper powf(x,y) return x**y
- */
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
 
 #include <math.h>
 #include <math_private.h>
 
 
-#ifdef __STDC__
-	float __powf(float x, float y)	/* wrapper powf */
-#else
-	float __powf(x,y)			/* wrapper powf */
-	float x,y;
-#endif
+/* wrapper powf */
+float
+__powf (float x, float y)
 {
-#ifdef _IEEE_LIBM
-	return  __ieee754_powf(x,y);
-#else
-	float z;
-	z=__ieee754_powf(x,y);
-	if(_LIB_VERSION == _IEEE_|| __isnanf(y)) return z;
-	if(__isnanf(x)) {
-	    if(y==(float)0.0)
-	        /* powf(NaN,0.0) */
-	        return (float)__kernel_standard((double)x,(double)y,142);
-	    else
-		return z;
-	}
-	if(x==(float)0.0) {
-	    if(y==(float)0.0)
-	        /* powf(0.0,0.0) */
-	        return (float)__kernel_standard((double)x,(double)y,120);
-	    if(__finitef(y)&&y<(float)0.0) {
-	      if (signbit (x) && signbit (z))
-	        /* powf(0.0,negative) */
-	        return (float)__kernel_standard((double)x,(double)y,123);
+  float z = __ieee754_powf (x, y);
+  if (__builtin_expect (!__finitef (z), 0))
+    {
+      if (_LIB_VERSION != _IEEE_)
+	{
+	  if (__isnanf (x))
+	    {
+	      if (y == 0.0f)
+		/* pow(NaN,0.0) */
+		return __kernel_standard_f (x, y, 142);
+	    }
+	  else if (__finitef (x) && __finitef (y))
+	    {
+	      if (__isnanf (z))
+		/* pow neg**non-int */
+		return __kernel_standard_f (x, y, 124);
+	      else if (x == 0.0f && y < 0.0f)
+		{
+		  if (signbit (x) && signbit (z))
+		    /* pow(-0.0,negative) */
+		    return __kernel_standard_f (x, y, 123);
+		  else
+		    /* pow(+0.0,negative) */
+		    return __kernel_standard_f (x, y, 143);
+		}
 	      else
-	        return (float)__kernel_standard((double)x,(double)y,143);
+		/* pow overflow */
+		return __kernel_standard_f (x, y, 121);
 	    }
-	    return z;
 	}
-	if(!__finitef(z)) {
-	    if(__finitef(x)&&__finitef(y)) {
-	        if(__isnanf(z))
-		    /* powf neg**non-int */
-	            return (float)__kernel_standard((double)x,(double)y,124);
-	        else
-		    /* powf overflow */
-	            return (float)__kernel_standard((double)x,(double)y,121);
-	    }
+    }
+  else if (__builtin_expect (z == 0.0f, 0) && __finitef (x) && __finitef (y)
+	   && _LIB_VERSION != _IEEE_)
+    {
+      if (x == 0.0f)
+	{
+	  if (y == 0.0f)
+	    /* pow(0.0,0.0) */
+	    return __kernel_standard_f (x, y, 120);
 	}
-	if(z==(float)0.0&&__finitef(x)&&__finitef(y))
-	    /* powf underflow */
-	    return (float)__kernel_standard((double)x,(double)y,122);
-	return z;
-#endif
+      else
+	/* pow underflow */
+	return __kernel_standard_f (x, y, 122);
+    }
+
+  return z;
 }
 weak_alias (__powf, powf)