X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fmath%2Filogb.c;h=64d40154d60ab065b8597d69faef4f76a2fac49d;hb=9532ae1318201d66b235a618df16aac0b3386630;hp=5a1819d85f4c31e1de8302095586eddea260d21a;hpb=be81f51030d90de8d5eb0b65dbdab3032d5cae23;p=musl

diff --git a/src/math/ilogb.c b/src/math/ilogb.c
index 5a1819d8..64d40154 100644
--- a/src/math/ilogb.c
+++ b/src/math/ilogb.c
@@ -3,22 +3,24 @@
 
 int ilogb(double x)
 {
-	union dshape u = {x};
-	int e = u.bits>>52 & 0x7ff;
+	#pragma STDC FENV_ACCESS ON
+	union {double f; uint64_t i;} u = {x};
+	uint64_t i = u.i;
+	int e = i>>52 & 0x7ff;
 
 	if (!e) {
-		u.bits <<= 12;
-		if (u.bits == 0) {
+		i <<= 12;
+		if (i == 0) {
 			FORCE_EVAL(0/0.0f);
 			return FP_ILOGB0;
 		}
 		/* subnormal x */
-		for (e = -0x3ff; u.bits < (uint64_t)1<<63; e--, u.bits<<=1);
+		for (e = -0x3ff; i>>63 == 0; e--, i<<=1);
 		return e;
 	}
 	if (e == 0x7ff) {
 		FORCE_EVAL(0/0.0f);
-		return u.bits<<12 ? FP_ILOGBNAN : INT_MAX;
+		return i<<12 ? FP_ILOGBNAN : INT_MAX;
 	}
 	return e - 0x3ff;
 }