diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libm/src/e_pow.c | 9 | ||||
-rw-r--r-- | lib/libm/src/e_powf.c | 5 | ||||
-rw-r--r-- | lib/libm/src/ld80/e_powl.c | 10 |
3 files changed, 15 insertions, 9 deletions
diff --git a/lib/libm/src/e_pow.c b/lib/libm/src/e_pow.c index 5fce17c8c7b..2af0e921b3e 100644 --- a/lib/libm/src/e_pow.c +++ b/lib/libm/src/e_pow.c @@ -24,13 +24,13 @@ * Special cases: * 1. (anything) ** 0 is 1 * 2. (anything) ** 1 is itself - * 3. (anything) ** NAN is NAN + * 3. (anything except 1) ** NAN is NAN * 4. NAN ** (anything except 0) is NAN * 5. +-(|x| > 1) ** +INF is +INF * 6. +-(|x| > 1) ** -INF is +0 * 7. +-(|x| < 1) ** +INF is +0 * 8. +-(|x| < 1) ** -INF is +INF - * 9. +-1 ** +-INF is NAN + * 9. +-1 ** +-INF is 1 * 10. +0 ** (+anything except 0, NAN) is +0 * 11. -0 ** (+anything except 0, NAN, odd integer) is +0 * 12. +0 ** (-anything except 0, NAN) is +INF @@ -109,6 +109,9 @@ pow(double x, double y) /* y==zero: x**0 = 1 */ if((iy|ly)==0) return one; + /* x==1: 1**y = 1, even if y is NaN */ + if (hx==0x3ff00000 && lx == 0) return one; + /* +-NaN return x+y */ if(ix > 0x7ff00000 || ((ix==0x7ff00000)&&(lx!=0)) || iy > 0x7ff00000 || ((iy==0x7ff00000)&&(ly!=0))) @@ -138,7 +141,7 @@ pow(double x, double y) if(ly==0) { if (iy==0x7ff00000) { /* y is +-inf */ if(((ix-0x3ff00000)|lx)==0) - return y - y; /* inf**+-1 is NaN */ + return one; /* (-1)**+-inf is 1 */ else if (ix >= 0x3ff00000)/* (|x|>1)**+-inf = inf,0 */ return (hy>=0)? y: zero; else /* (|x|<1)**-,+inf = inf,0 */ diff --git a/lib/libm/src/e_powf.c b/lib/libm/src/e_powf.c index d6e52d8b99b..3c4269d7146 100644 --- a/lib/libm/src/e_powf.c +++ b/lib/libm/src/e_powf.c @@ -64,6 +64,9 @@ powf(float x, float y) /* y==zero: x**0 = 1 */ if(iy==0) return one; + /* x==1: 1**y = 1, even if y is NaN */ + if (hx==0x3f800000) return one; + /* +-NaN return x+y */ if(ix > 0x7f800000 || iy > 0x7f800000) @@ -87,7 +90,7 @@ powf(float x, float y) /* special value of y */ if (iy==0x7f800000) { /* y is +-inf */ if (ix==0x3f800000) - return y - y; /* inf**+-1 is NaN */ + return one; /* (-1)**+-inf is NaN */ else if (ix > 0x3f800000)/* (|x|>1)**+-inf = inf,0 */ return (hy>=0)? y: zero; else /* (|x|<1)**-,+inf = inf,0 */ diff --git a/lib/libm/src/ld80/e_powl.c b/lib/libm/src/ld80/e_powl.c index d05de530531..f72dd8d68b8 100644 --- a/lib/libm/src/ld80/e_powl.c +++ b/lib/libm/src/ld80/e_powl.c @@ -1,4 +1,4 @@ -/* $OpenBSD: e_powl.c,v 1.3 2011/07/20 21:02:51 martynas Exp $ */ +/* $OpenBSD: e_powl.c,v 1.4 2013/08/02 20:23:28 kettenis Exp $ */ /* * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net> @@ -211,6 +211,9 @@ long e; if( y == 0.0L ) return( 1.0L ); +if( x == 1.0L ) + return( 1.0L ); + if( isnan(x) ) return( x ); if( isnan(y) ) @@ -219,10 +222,7 @@ if( isnan(y) ) if( y == 1.0L ) return( x ); -if( !isfinite(y) && (x == -1.0L || x == 1.0L) ) - return y - y; /* +-1**inf is NaN */ - -if( x == 1.0L ) +if( !isfinite(y) && x == -1.0L ) return( 1.0L ); if( y >= LDBL_MAX ) |