X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fmath%2Fpow.c;h=3ddc1b6ff8ebfd0266e70fc9bd3cb372303a9df0;hb=68a5a23abcb9649f05728db4cf50bb4498937855;hp=ac3abc0fdbb81b4d4d4f082ac62f6521a920e6cb;hpb=f29fea00b5bc72d4b8abccba2bb1e312684d1fce;p=musl

diff --git a/src/math/pow.c b/src/math/pow.c
index ac3abc0f..3ddc1b6f 100644
--- a/src/math/pow.c
+++ b/src/math/pow.c
@@ -125,11 +125,11 @@ double pow(double x, double y)
 		else if (iy >= 0x3ff00000) {
 			k = (iy>>20) - 0x3ff;  /* exponent */
 			if (k > 20) {
-				j = ly>>(52-k);
+				uint32_t j = ly>>(52-k);
 				if ((j<<(52-k)) == ly)
 					yisint = 2 - (j&1);
 			} else if (ly == 0) {
-				j = iy>>(20-k);
+				uint32_t j = iy>>(20-k);
 				if ((j<<(20-k)) == iy)
 					yisint = 2 - (j&1);
 			}
@@ -143,11 +143,23 @@ double pow(double x, double y)
 				return 1.0;
 			else if (ix >= 0x3ff00000) /* (|x|>1)**+-inf = inf,0 */
 				return hy >= 0 ? y : 0.0;
-			else if ((ix|lx) != 0)     /* (|x|<1)**+-inf = 0,inf if x!=0 */
+			else                       /* (|x|<1)**+-inf = 0,inf */
 				return hy >= 0 ? 0.0 : -y;
 		}
-		if (iy == 0x3ff00000)    /* y is +-1 */
-			return hy >= 0 ? x : 1.0/x;
+		if (iy == 0x3ff00000) {    /* y is +-1 */
+			if (hy >= 0)
+				return x;
+			y = 1/x;
+#if FLT_EVAL_METHOD!=0
+			{
+				union {double f; uint64_t i;} u = {y};
+				uint64_t i = u.i & -1ULL/2;
+				if (i>>52 == 0 && (i&(i-1)))
+					FORCE_EVAL((float)y);
+			}
+#endif
+			return y;
+		}
 		if (hy == 0x40000000)    /* y is 2 */
 			return x*x;
 		if (hy == 0x3fe00000) {  /* y is 0.5 */