8311207: Cleanup for Optimization for UUID.toString

src/java.base/share/classes/java/util/HexDigits.java

@@ -105,18 +105,18 @@ private HexDigits() {
     /**
      * Return a big-endian packed integer for the 4 ASCII bytes for an input unsigned short value.
      */
-    static int packDigits16(int b) {
-        return (DIGITS[(b >> 8) & 0xff] << 16) | DIGITS[b & 0xff];
+    static int packDigits(int b0, int b1) {
+        return (DIGITS[b0 & 0xff] << 16) | DIGITS[b1 & 0xff];
     }
 
     /**
      * Return a big-endian packed long for the 8 ASCII bytes for an input unsigned int value.
      */
-    static long packDigits32(int b) {
-        return (((long) DIGITS[(b >> 24) & 0xff]) << 48)
-                | (((long) DIGITS[(b >> 16) & 0xff]) << 32)
-                | (DIGITS[(b >> 8) & 0xff] << 16)
-                | DIGITS[b & 0xff];
+    static long packDigits(int b0, int b1, int b2, int b3) {
+        return (((long) DIGITS[b0 & 0xff]) << 48)
+                | (((long) DIGITS[b1 & 0xff]) << 32)
+                | (DIGITS[b2 & 0xff] << 16)
+                | DIGITS[b3 & 0xff];
     }
 
     @Override

src/java.base/share/classes/java/util/UUID.java

@@ -473,36 +473,36 @@ public String toString() {
         unsafe.putLongUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET,
-                HexDigits.packDigits32((int) (msb >> 32)),
+                HexDigits.packDigits((int) (msb >> 56), (int) (msb >> 48), (int) (msb >> 40), (int) (msb >> 32)),
                 true);
         buf[8] = '-';
         unsafe.putIntUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET + 9,
-                HexDigits.packDigits16(((int) msb) >> 16),
+                HexDigits.packDigits(((int) msb) >> 24, ((int) msb) >> 16),
                 true);
         buf[13] = '-';
         unsafe.putIntUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET + 14,
-                HexDigits.packDigits16((int) msb),
+                HexDigits.packDigits(((int) msb) >> 8, (int) msb),
                 true);
         buf[18] = '-';
         unsafe.putIntUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET + 19,
-                HexDigits.packDigits16((int) (lsb >> 48)),
+                HexDigits.packDigits((int) (lsb >> 56), (int) (lsb >> 48)),
                 true);
         buf[23] = '-';
         unsafe.putLongUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET + 24,
-                HexDigits.packDigits32((int) (lsb >> 16)),
+                HexDigits.packDigits(((int) (lsb >> 40)), (int) (lsb >> 32), ((int) lsb) >> 24, ((int) lsb) >> 16),
                 true);
         unsafe.putIntUnaligned(
                 buf,
                 Unsafe.ARRAY_BYTE_BASE_OFFSET + 32,
-                HexDigits.packDigits16((int) lsb),
+                HexDigits.packDigits(((int) lsb) >> 8, (int) lsb),
                 true);
 
         try {