--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir.sparc/src/org/graalvm/compiler/lir/sparc/SPARCSaveRegistersOp.java	2017-03-20 17:39:40.000000000 -0700
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir.sparc/src/org/graalvm/compiler/lir/sparc/SPARCSaveRegistersOp.java	2017-03-20 17:39:40.000000000 -0700
@@ -28,8 +28,6 @@
 import static jdk.vm.ci.code.ValueUtil.isStackSlot;
 
 import java.util.Arrays;
-import java.util.Set;
-
 import org.graalvm.compiler.asm.sparc.SPARCAddress;
 import org.graalvm.compiler.asm.sparc.SPARCMacroAssembler;
 import org.graalvm.compiler.lir.LIRInstructionClass;
@@ -38,6 +36,7 @@
 import org.graalvm.compiler.lir.StandardOp.SaveRegistersOp;
 import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
 import org.graalvm.compiler.lir.framemap.FrameMap;
+import org.graalvm.util.EconomicSet;
 
 import jdk.vm.ci.code.Register;
 import jdk.vm.ci.code.RegisterSaveLayout;
@@ -65,16 +64,16 @@
     @Def(STACK) protected final AllocatableValue[] slots;
 
     /**
-     * Specifies if {@link #remove(Set)} should have an effect.
+     * Specifies if {@link #remove(EconomicSet)} should have an effect.
      */
     protected final boolean supportsRemove;
 
     /**
      *
      * @param savedRegisters the registers saved by this operation which may be subject to
-     *            {@linkplain #remove(Set) pruning}
+     *            {@linkplain #remove(EconomicSet) pruning}
      * @param savedRegisterLocations the slots to which the registers are saved
-     * @param supportsRemove determines if registers can be {@linkplain #remove(Set) pruned}
+     * @param supportsRemove determines if registers can be {@linkplain #remove(EconomicSet) pruned}
      */
     public SPARCSaveRegistersOp(Register[] savedRegisters, AllocatableValue[] savedRegisterLocations, boolean supportsRemove) {
         super(TYPE, SIZE);
@@ -117,14 +116,14 @@
     }
 
     @Override
-    public int remove(Set<Register> doNotSave) {
+    public int remove(EconomicSet<Register> doNotSave) {
         if (!supportsRemove) {
             throw new UnsupportedOperationException();
         }
         return prune(doNotSave, savedRegisters);
     }
 
-    static int prune(Set<Register> toRemove, Register[] registers) {
+    static int prune(EconomicSet<Register> toRemove, Register[] registers) {
         int pruned = 0;
         for (int i = 0; i < registers.length; i++) {
             if (registers[i] != null) {