newlib/libm/math: Make pow/powf return qnan for snan arg

The IEEE spec for pow only has special case for x**0 and 1**y when x/y
are quiet NaN. For signaling NaN, the general case applies and these functions
should signal the invalid exception and return a quiet NaN.

Signed-off-by: Keith Packard <keithp@keithp.com>
This commit is contained in:
Keith Packard via Newlib 2020-03-25 17:18:21 -07:00 committed by Corinna Vinschen
parent 3439f3b0e9
commit 6295d75913
2 changed files with 16 additions and 7 deletions

View File

@ -58,6 +58,8 @@
*/ */
#include "fdlibm.h" #include "fdlibm.h"
#include "math_config.h"
#if __OBSOLETE_MATH #if __OBSOLETE_MATH
#ifndef _DOUBLE_IS_32BITS #ifndef _DOUBLE_IS_32BITS
@ -116,14 +118,17 @@ ivln2_l = 1.92596299112661746887e-08; /* 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail*/
EXTRACT_WORDS(hy,ly,y); EXTRACT_WORDS(hy,ly,y);
ix = hx&0x7fffffff; iy = hy&0x7fffffff; ix = hx&0x7fffffff; iy = hy&0x7fffffff;
/* y==zero: x**0 = 1 */ /* y==zero: x**0 = 1 unless x is snan */
if((iy|ly)==0) return one; if((iy|ly)==0) {
if (issignaling_inline(x)) return x + y;
return one;
}
/* x|y==NaN return NaN unless x==1 then return 1 */ /* x|y==NaN return NaN unless x==1 then return 1 */
if(ix > 0x7ff00000 || ((ix==0x7ff00000)&&(lx!=0)) || if(ix > 0x7ff00000 || ((ix==0x7ff00000)&&(lx!=0)) ||
iy > 0x7ff00000 || ((iy==0x7ff00000)&&(ly!=0))) { iy > 0x7ff00000 || ((iy==0x7ff00000)&&(ly!=0))) {
if(((hx-0x3ff00000)|lx)==0) return one; if(((hx-0x3ff00000)|lx)==0 && !issignaling_inline(y)) return one;
else return nan(""); else return x + y;
} }
/* determine if y is an odd int when x < 0 /* determine if y is an odd int when x < 0

View File

@ -14,6 +14,7 @@
*/ */
#include "fdlibm.h" #include "fdlibm.h"
#include "math_config.h"
#if __OBSOLETE_MATH #if __OBSOLETE_MATH
#ifdef __v810__ #ifdef __v810__
@ -74,13 +75,16 @@ ivln2_l = 7.0526075433e-06; /* 0x36eca570 =1/ln2 tail*/
ix = hx&0x7fffffff; iy = hy&0x7fffffff; ix = hx&0x7fffffff; iy = hy&0x7fffffff;
/* y==zero: x**0 = 1 */ /* y==zero: x**0 = 1 */
if(FLT_UWORD_IS_ZERO(iy)) return one; if(FLT_UWORD_IS_ZERO(iy)) {
if (issignalingf_inline(x)) return x + y;
return one;
}
/* x|y==NaN return NaN unless x==1 then return 1 */ /* x|y==NaN return NaN unless x==1 then return 1 */
if(FLT_UWORD_IS_NAN(ix) || if(FLT_UWORD_IS_NAN(ix) ||
FLT_UWORD_IS_NAN(iy)) { FLT_UWORD_IS_NAN(iy)) {
if(hx==0x3f800000) return one; if(hx==0x3f800000 && !issignalingf_inline(y)) return one;
else return nanf(""); else return x + y;
} }
/* determine if y is an odd int when x < 0 /* determine if y is an odd int when x < 0