--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core/src/org/graalvm/compiler/core/phases/EconomyMidTier.java	Thu Oct 31 14:23:06 2019 -0700
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core/src/org/graalvm/compiler/core/phases/EconomyMidTier.java	Thu Oct 31 16:54:16 2019 -0700
@@ -24,11 +24,8 @@
 
 package org.graalvm.compiler.core.phases;
 
-import static org.graalvm.compiler.core.common.GraalOptions.ImmutableCode;
-
 import org.graalvm.compiler.nodes.spi.LoweringTool;
 import org.graalvm.compiler.options.OptionValues;
-import org.graalvm.compiler.phases.PhaseSuite;
 import org.graalvm.compiler.phases.common.CanonicalizerPhase;
 import org.graalvm.compiler.phases.common.FrameStateAssignmentPhase;
 import org.graalvm.compiler.phases.common.GuardLoweringPhase;
@@ -38,23 +35,15 @@
 import org.graalvm.compiler.phases.common.WriteBarrierAdditionPhase;
 import org.graalvm.compiler.phases.tiers.MidTierContext;
 
-public class EconomyMidTier extends PhaseSuite<MidTierContext> {
+public class EconomyMidTier extends BaseTier<MidTierContext> {
 
     public EconomyMidTier(OptionValues options) {
-        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();
-        if (ImmutableCode.getValue(options)) {
-            canonicalizer.disableReadCanonicalization();
-        }
+        CanonicalizerPhase canonicalizer = this.createCanonicalizerPhase(options);
         appendPhase(new RemoveValueProxyPhase());
-
         appendPhase(new LoopSafepointInsertionPhase());
-
         appendPhase(new GuardLoweringPhase());
-
         appendPhase(new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.MID_TIER));
-
         appendPhase(new FrameStateAssignmentPhase());
-
         appendPhase(new WriteBarrierAdditionPhase());
     }
 }