# HG changeset patch
# User igerasim
# Date 1521530116 25200
#      Tue Mar 20 00:15:16 2018 -0700
# Node ID e670e060ce2360ede622df78bcac16c53fb7a6f3
# Parent  778e4516409c902dcad1af49adf05b5a339af86a
[mq]: 8199843-Optimize-Integer-Long-highestOneBit

diff --git a/src/java.base/share/classes/java/lang/Integer.java b/src/java.base/share/classes/java/lang/Integer.java
--- a/src/java.base/share/classes/java/lang/Integer.java
+++ b/src/java.base/share/classes/java/lang/Integer.java
@@ -1574,13 +1574,7 @@
      * @since 1.5
      */
     public static int highestOneBit(int i) {
-        // HD, Figure 3-1
-        i |= (i >>  1);
-        i |= (i >>  2);
-        i |= (i >>  4);
-        i |= (i >>  8);
-        i |= (i >> 16);
-        return i - (i >>> 1);
+        return i == 0 ? 0 : MIN_VALUE >>> numberOfLeadingZeros(i);
     }
 
     /**
diff --git a/src/java.base/share/classes/java/lang/Long.java b/src/java.base/share/classes/java/lang/Long.java
--- a/src/java.base/share/classes/java/lang/Long.java
+++ b/src/java.base/share/classes/java/lang/Long.java
@@ -1719,14 +1719,7 @@
      * @since 1.5
      */
     public static long highestOneBit(long i) {
-        // HD, Figure 3-1
-        i |= (i >>  1);
-        i |= (i >>  2);
-        i |= (i >>  4);
-        i |= (i >>  8);
-        i |= (i >> 16);
-        i |= (i >> 32);
-        return i - (i >>> 1);
+        return i == 0 ? 0 : MIN_VALUE >>> numberOfLeadingZeros(i);
     }
 
     /**