--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements.amd64/src/org/graalvm/compiler/replacements/amd64/AMD64StringUTF16Substitutions.java	Thu Jun 27 03:10:52 2019 +0200
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements.amd64/src/org/graalvm/compiler/replacements/amd64/AMD64StringUTF16Substitutions.java	Thu Jun 27 03:33:44 2019 +0200
@@ -103,12 +103,7 @@
 
     @MethodSubstitution
     public static int indexOfCharUnsafe(byte[] value, int ch, int fromIndex, int max) {
-        Pointer sourcePointer = charOffsetPointer(value, fromIndex);
-        int result = AMD64ArrayIndexOf.indexOf1Char(sourcePointer, max - fromIndex, (char) ch);
-        if (result != -1) {
-            return result + fromIndex;
-        }
-        return result;
+        return AMD64ArrayIndexOf.indexOf1Char(value, max, fromIndex, (char) ch);
     }
 
     private static Word pointer(byte[] target) {
@@ -125,39 +120,26 @@
         ReplacementsUtil.runtimeAssert(targetCount > 0, "StringUTF16.indexOfUnsafe invalid args: targetCount <= 0");
         ReplacementsUtil.runtimeAssert(targetCount <= length(target), "StringUTF16.indexOfUnsafe invalid args: targetCount > length(target)");
         ReplacementsUtil.runtimeAssert(sourceCount >= targetCount, "StringUTF16.indexOfUnsafe invalid args: sourceCount < targetCount");
-        int totalOffset = fromIndex;
         if (targetCount == 1) {
-            Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-            int indexOfResult = AMD64ArrayIndexOf.indexOf1Char(sourcePointer, sourceCount - fromIndex, StringUTF16Substitutions.getChar(target, 0));
-            if (indexOfResult >= 0) {
-                return indexOfResult + totalOffset;
-            }
-            return indexOfResult;
+            return AMD64ArrayIndexOf.indexOf1Char(source, sourceCount, fromIndex, StringUTF16Substitutions.getChar(target, 0));
         } else if (targetCount == 2) {
-            Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-            int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, sourceCount - fromIndex, StringUTF16Substitutions.getChar(target, 0),
-                            StringUTF16Substitutions.getChar(target, 1));
-            if (indexOfResult >= 0) {
-                return indexOfResult + totalOffset;
-            }
-            return indexOfResult;
+            return AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(source, sourceCount, fromIndex, StringUTF16Substitutions.getChar(target, 0), StringUTF16Substitutions.getChar(target, 1));
         } else {
-            int haystackLength = sourceCount - (fromIndex + (targetCount - 2));
-            while (haystackLength > 0) {
-                Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-                int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, haystackLength, StringUTF16Substitutions.getChar(target, 0),
+            int haystackLength = sourceCount - (targetCount - 2);
+            int offset = fromIndex;
+            while (offset < haystackLength) {
+                int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(source, haystackLength, offset, StringUTF16Substitutions.getChar(target, 0),
                                 StringUTF16Substitutions.getChar(target, 1));
                 if (indexOfResult < 0) {
                     return -1;
                 }
-                totalOffset += indexOfResult;
-                haystackLength -= (indexOfResult + 1);
-                Pointer cmpSourcePointer = charOffsetPointer(source, totalOffset);
+                offset = indexOfResult;
+                Pointer cmpSourcePointer = charOffsetPointer(source, offset);
                 Pointer targetPointer = pointer(target);
                 if (ArrayRegionEqualsNode.regionEquals(cmpSourcePointer, targetPointer, targetCount, JavaKind.Char)) {
-                    return totalOffset;
+                    return offset;
                 }
-                totalOffset++;
+                offset++;
             }
             return -1;
         }
@@ -169,37 +151,25 @@
         ReplacementsUtil.runtimeAssert(targetCount > 0, "StringUTF16.indexOfLatin1Unsafe invalid args: targetCount <= 0");
         ReplacementsUtil.runtimeAssert(targetCount <= target.length, "StringUTF16.indexOfLatin1Unsafe invalid args: targetCount > length(target)");
         ReplacementsUtil.runtimeAssert(sourceCount >= targetCount, "StringUTF16.indexOfLatin1Unsafe invalid args: sourceCount < targetCount");
-        int totalOffset = fromIndex;
         if (targetCount == 1) {
-            Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-            int indexOfResult = AMD64ArrayIndexOf.indexOf1Char(sourcePointer, sourceCount - fromIndex, (char) Byte.toUnsignedInt(target[0]));
-            if (indexOfResult >= 0) {
-                return indexOfResult + totalOffset;
-            }
-            return indexOfResult;
+            return AMD64ArrayIndexOf.indexOf1Char(source, sourceCount, fromIndex, (char) Byte.toUnsignedInt(target[0]));
         } else if (targetCount == 2) {
-            Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-            int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, sourceCount - fromIndex, (char) Byte.toUnsignedInt(target[0]), (char) Byte.toUnsignedInt(target[1]));
-            if (indexOfResult >= 0) {
-                return indexOfResult + totalOffset;
-            }
-            return indexOfResult;
+            return AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(source, sourceCount, fromIndex, (char) Byte.toUnsignedInt(target[0]), (char) Byte.toUnsignedInt(target[1]));
         } else {
-            int haystackLength = sourceCount - (fromIndex + (targetCount - 2));
-            while (haystackLength > 0) {
-                Pointer sourcePointer = charOffsetPointer(source, totalOffset);
-                int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(sourcePointer, haystackLength, (char) Byte.toUnsignedInt(target[0]), (char) Byte.toUnsignedInt(target[1]));
+            int haystackLength = sourceCount - (targetCount - 2);
+            int offset = fromIndex;
+            while (offset < haystackLength) {
+                int indexOfResult = AMD64ArrayIndexOf.indexOfTwoConsecutiveChars(source, haystackLength, offset, (char) Byte.toUnsignedInt(target[0]), (char) Byte.toUnsignedInt(target[1]));
                 if (indexOfResult < 0) {
                     return -1;
                 }
-                totalOffset += indexOfResult;
-                haystackLength -= (indexOfResult + 1);
-                Pointer cmpSourcePointer = charOffsetPointer(source, totalOffset);
+                offset = indexOfResult;
+                Pointer cmpSourcePointer = charOffsetPointer(source, offset);
                 Pointer targetPointer = pointer(target);
                 if (ArrayRegionEqualsNode.regionEquals(cmpSourcePointer, targetPointer, targetCount, JavaKind.Char, JavaKind.Byte)) {
-                    return totalOffset;
+                    return offset;
                 }
-                totalOffset++;
+                offset++;
             }
             return -1;
         }