numeric.c:S_mulexp10 -- quit when you can

From: "Craig A. Berry" <craigberry@mac.com>
Message-Id: <a05111b01b926db404884@[172.16.52.1]>

p4raw-id: //depot/perl@17074

1 files changed, 4 insertions, 1 deletions

diff --git a/numeric.c b/numeric.c
index d2144164cd..1cb24d2273 100644
--- a/numeric.c
+++ b/numeric.c
@@ -766,8 +766,11 @@ S_mulexp10(NV value, I32 exponent)
 	if (exponent & bit) {
 	    exponent ^= bit;
 	    result *= power;
+	    /* Floating point exceptions are supposed to be turned off,
+	     *  but if we're obviously done, don't risk another iteration.  
+	     */
+	     if (exponent == 0) break;
 	}
-	/* Floating point exceptions are supposed to be turned off. */
 	power *= power;
     }
     return negative ? value / result : value * result;