--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir/src/org/graalvm/compiler/lir/alloc/lsra/MoveResolver.java	2017-03-20 17:39:51.000000000 -0700
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir/src/org/graalvm/compiler/lir/alloc/lsra/MoveResolver.java	2017-03-20 17:39:50.000000000 -0700
@@ -27,8 +27,6 @@
 import static jdk.vm.ci.code.ValueUtil.isRegister;
 
 import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
 
 import org.graalvm.compiler.core.common.LIRKind;
 import org.graalvm.compiler.debug.Debug;
@@ -38,6 +36,8 @@
 import org.graalvm.compiler.lir.LIRInsertionBuffer;
 import org.graalvm.compiler.lir.LIRInstruction;
 import org.graalvm.compiler.lir.LIRValueUtil;
+import org.graalvm.util.Equivalence;
+import org.graalvm.util.EconomicSet;
 
 import jdk.vm.ci.meta.AllocatableValue;
 import jdk.vm.ci.meta.Constant;
@@ -54,9 +54,9 @@
     private int insertIdx;
     private LIRInsertionBuffer insertionBuffer; // buffer where moves are inserted
 
-    private final List<Interval> mappingFrom;
-    private final List<Constant> mappingFromOpr;
-    private final List<Interval> mappingTo;
+    private final ArrayList<Interval> mappingFrom;
+    private final ArrayList<Constant> mappingFromOpr;
+    private final ArrayList<Interval> mappingTo;
     private boolean multipleReadsAllowed;
     private final int[] registerBlocked;
 
@@ -146,7 +146,7 @@
             }
         }
 
-        HashSet<Value> usedRegs = new HashSet<>();
+        EconomicSet<Value> usedRegs = EconomicSet.create(Equivalence.DEFAULT);
         if (!areMultipleReadsAllowed()) {
             for (i = 0; i < mappingFrom.size(); i++) {
                 Interval interval = mappingFrom.get(i);
@@ -175,7 +175,7 @@
     }
 
     protected void verifyStackSlotMapping() {
-        HashSet<Value> usedRegs = new HashSet<>();
+        EconomicSet<Value> usedRegs = EconomicSet.create(Equivalence.DEFAULT);
         for (int i = 0; i < mappingFrom.size(); i++) {
             Interval interval = mappingFrom.get(i);
             if (interval != null && !isRegister(interval.location())) {
@@ -251,7 +251,7 @@
         return isRegister(location);
     }
 
-    private void createInsertionBuffer(List<LIRInstruction> list) {
+    private void createInsertionBuffer(ArrayList<LIRInstruction> list) {
         assert !insertionBuffer.initialized() : "overwriting existing buffer";
         insertionBuffer.init(list);
     }
@@ -427,14 +427,14 @@
         }
     }
 
-    void setInsertPosition(List<LIRInstruction> insertList, int insertIdx) {
+    void setInsertPosition(ArrayList<LIRInstruction> insertList, int insertIdx) {
         assert this.insertIdx == -1 : "use moveInsertPosition instead of setInsertPosition when data already set";
 
         createInsertionBuffer(insertList);
         this.insertIdx = insertIdx;
     }
 
-    void moveInsertPosition(List<LIRInstruction> newInsertList, int newInsertIdx) {
+    void moveInsertPosition(ArrayList<LIRInstruction> newInsertList, int newInsertIdx) {
         if (insertionBuffer.lirList() != null && (insertionBuffer.lirList() != newInsertList || this.insertIdx != newInsertIdx)) {
             // insert position changed . resolve current mappings
             resolveMappings();