--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements.amd64/src/org/graalvm/compiler/replacements/amd64/AMD64StringSubstitutions.java	Fri Feb 02 10:37:48 2018 -0500
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements.amd64/src/org/graalvm/compiler/replacements/amd64/AMD64StringSubstitutions.java	Fri Feb 02 17:28:17 2018 -0800
@@ -23,12 +23,15 @@
 package org.graalvm.compiler.replacements.amd64;
 
 import org.graalvm.compiler.api.replacements.ClassSubstitution;
+import org.graalvm.compiler.api.replacements.Fold;
+import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;
 import org.graalvm.compiler.api.replacements.MethodSubstitution;
+import org.graalvm.compiler.core.common.spi.ArrayOffsetProvider;
 import org.graalvm.compiler.graph.Node.ConstantNodeParameter;
 import org.graalvm.compiler.word.Word;
 import org.graalvm.word.Pointer;
 
-import sun.misc.Unsafe;
+import jdk.vm.ci.meta.JavaKind;
 
 // JaCoCo Exclude
 
@@ -38,6 +41,19 @@
 @ClassSubstitution(String.class)
 public class AMD64StringSubstitutions {
 
+    @Fold
+    static int charArrayBaseOffset(@InjectedParameter ArrayOffsetProvider arrayOffsetProvider) {
+        return arrayOffsetProvider.arrayBaseOffset(JavaKind.Char);
+    }
+
+    @Fold
+    static int charArrayIndexScale(@InjectedParameter ArrayOffsetProvider arrayOffsetProvider) {
+        return arrayOffsetProvider.arrayScalingFactor(JavaKind.Char);
+    }
+
+    /** Marker value for the {@link InjectedParameter} injected parameter. */
+    static final ArrayOffsetProvider INJECTED = null;
+
     // Only exists in JDK <= 8
     @MethodSubstitution(isStatic = true, optional = true)
     public static int indexOf(char[] source, int sourceOffset, int sourceCount,
@@ -62,8 +78,8 @@
         }
         assert sourceCount - fromIndex > 0 && targetCount > 0;
 
-        Pointer sourcePointer = Word.objectToTrackedPointer(source).add(Unsafe.ARRAY_CHAR_BASE_OFFSET).add(totalOffset * Unsafe.ARRAY_CHAR_INDEX_SCALE);
-        Pointer targetPointer = Word.objectToTrackedPointer(target).add(Unsafe.ARRAY_CHAR_BASE_OFFSET).add(targetOffset * Unsafe.ARRAY_CHAR_INDEX_SCALE);
+        Pointer sourcePointer = Word.objectToTrackedPointer(source).add(charArrayBaseOffset(INJECTED)).add(totalOffset * charArrayIndexScale(INJECTED));
+        Pointer targetPointer = Word.objectToTrackedPointer(target).add(charArrayBaseOffset(INJECTED)).add(targetOffset * charArrayIndexScale(INJECTED));
         int result = AMD64StringIndexOfNode.optimizedStringIndexPointer(sourcePointer, sourceCount - fromIndex, targetPointer, targetCount);
         if (result >= 0) {
             return result + totalOffset;