diff --git a/lib/math/int_log.c b/lib/math/int_log.c
index 322df25a22d6..ea98fc0b3fe2 100644
--- a/lib/math/int_log.c
+++ b/lib/math/int_log.c
@@ -91,7 +91,7 @@ unsigned int intlog2(u32 value)
 	 *	so we would use the entry 0x18
 	 */
 	significand = value << (31 - msb);
-	logentry = (significand >> 23) & 0xff;
+	logentry = (significand >> 23) % ARRAY_SIZE(logtable);
 
 	/**
 	 *	last step we do is interpolation because of the
@@ -109,7 +109,7 @@ unsigned int intlog2(u32 value)
 	 *	logtable_next is 256
 	 */
 	interpolation = ((significand & 0x7fffff) *
-			((logtable[(logentry + 1) & 0xff] -
+			((logtable[(logentry + 1) % ARRAY_SIZE(logtable)] -
 			  logtable[logentry]) & 0xffff)) >> 15;
 
 	/* now we return the result */