# HG changeset patch
# User Doug Simon <doug.simon@oracle.com>
# Date 1410204198 -7200
# Node ID 37d6d174bc40027f259c2237e57ea3ad201f88b0
# Parent  3c54a098455f6b396c970eb8bc427b0c1023c608
denote certain applications of DeadCodeEliminationPhase as optional and only run them if -G:-ReduceDCE

diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalCompiler.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalCompiler.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalCompiler.java	Mon Sep 08 21:23:18 2014 +0200
@@ -25,6 +25,7 @@
 import static com.oracle.graal.compiler.GraalCompiler.Options.*;
 import static com.oracle.graal.compiler.MethodFilter.*;
 import static com.oracle.graal.compiler.common.GraalOptions.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 
 import java.util.*;
 
@@ -167,7 +168,7 @@
             HighTierContext highTierContext = new HighTierContext(providers, assumptions, cache, graphBuilderSuite, optimisticOpts);
             if (graph.start().next() == null) {
                 graphBuilderSuite.apply(graph, highTierContext);
-                new DeadCodeEliminationPhase().apply(graph);
+                new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
             } else {
                 Debug.dump(graph, "initial state");
             }
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/HighTier.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/HighTier.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/HighTier.java	Mon Sep 08 21:23:18 2014 +0200
@@ -24,12 +24,14 @@
 
 import static com.oracle.graal.compiler.common.GraalOptions.*;
 import static com.oracle.graal.compiler.phases.HighTier.Options.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
+
 import com.oracle.graal.loop.phases.*;
 import com.oracle.graal.nodes.spi.*;
 import com.oracle.graal.options.*;
 import com.oracle.graal.phases.*;
 import com.oracle.graal.phases.common.*;
-import com.oracle.graal.phases.common.cfs.IterativeFlowSensitiveReductionPhase;
+import com.oracle.graal.phases.common.cfs.*;
 import com.oracle.graal.phases.common.inlining.*;
 import com.oracle.graal.phases.tiers.*;
 import com.oracle.graal.virtual.phases.ea.*;
@@ -56,7 +58,7 @@
                 appendPhase(new IterativeInliningPhase(canonicalizer));
             } else {
                 appendPhase(new InliningPhase(canonicalizer));
-                appendPhase(new DeadCodeEliminationPhase());
+                appendPhase(new DeadCodeEliminationPhase(OPTIONAL));
 
                 boolean reduceOrEliminate = FlowSensitiveReduction.getValue() || ConditionalElimination.getValue();
                 if (reduceOrEliminate && OptCanonicalizer.getValue()) {
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LowTier.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LowTier.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LowTier.java	Mon Sep 08 21:23:18 2014 +0200
@@ -23,6 +23,7 @@
 package com.oracle.graal.compiler.phases;
 
 import static com.oracle.graal.compiler.common.GraalOptions.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 
 import com.oracle.graal.nodes.spi.*;
 import com.oracle.graal.options.*;
@@ -63,6 +64,6 @@
 
         appendPhase(new UseTrappingNullChecksPhase());
 
-        appendPhase(new DeadCodeEliminationPhase());
+        appendPhase(new DeadCodeEliminationPhase(REQUIRED));
     }
 }
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/phases/OnStackReplacementPhase.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/phases/OnStackReplacementPhase.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/phases/OnStackReplacementPhase.java	Mon Sep 08 21:23:18 2014 +0200
@@ -22,6 +22,8 @@
  */
 package com.oracle.graal.hotspot.phases;
 
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
+
 import com.oracle.graal.api.code.*;
 import com.oracle.graal.compiler.common.*;
 import com.oracle.graal.debug.*;
@@ -109,6 +111,6 @@
         GraphUtil.killCFG(start);
 
         Debug.dump(graph, "OnStackReplacement result");
-        new DeadCodeEliminationPhase().apply(graph);
+        new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
     }
 }
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/ConvertDeoptimizeToGuardPhase.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/ConvertDeoptimizeToGuardPhase.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/ConvertDeoptimizeToGuardPhase.java	Mon Sep 08 21:23:18 2014 +0200
@@ -22,6 +22,8 @@
  */
 package com.oracle.graal.phases.common;
 
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
+
 import java.util.*;
 
 import com.oracle.graal.api.meta.*;
@@ -101,7 +103,7 @@
             }
         }
 
-        new DeadCodeEliminationPhase().apply(graph);
+        new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
     }
 
     private void visitDeoptBegin(BeginNode deoptBegin, DeoptimizationAction deoptAction, DeoptimizationReason deoptReason, StructuredGraph graph) {
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/DeadCodeEliminationPhase.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/DeadCodeEliminationPhase.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/DeadCodeEliminationPhase.java	Mon Sep 08 21:23:18 2014 +0200
@@ -22,18 +22,54 @@
  */
 package com.oracle.graal.phases.common;
 
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Options.*;
+
 import com.oracle.graal.debug.*;
 import com.oracle.graal.graph.*;
 import com.oracle.graal.nodes.*;
+import com.oracle.graal.options.*;
 import com.oracle.graal.phases.*;
 
 public class DeadCodeEliminationPhase extends Phase {
 
+    public static class Options {
+        // @formatter:off
+        @Option(help = "Disable optional dead code eliminations")
+        public static final OptionValue<Boolean> ReduceDCE = new OptionValue<>(true);
+        // @formatter:on
+    }
+
     // Metrics
     private static final DebugMetric metricNodesRemoved = Debug.metric("NodesRemoved");
 
+    public enum Optionality {
+        OPTIONAL,
+        REQUIRED;
+    }
+
+    /**
+     * Creates a dead code elimination phase that will be run irrespective of
+     * {@link Options#ReduceDCE}.
+     */
+    public DeadCodeEliminationPhase() {
+        this(Optionality.REQUIRED);
+    }
+
+    /**
+     * Creates a dead code elimination phase that will be run only if it is
+     * {@linkplain Optionality#REQUIRED non-optional} or {@link Options#ReduceDCE} is false.
+     */
+    public DeadCodeEliminationPhase(Optionality optionality) {
+        this.optional = optionality == Optionality.OPTIONAL;
+    }
+
+    private final boolean optional;
+
     @Override
     public void run(StructuredGraph graph) {
+        if (optional && ReduceDCE.getValue()) {
+            return;
+        }
         NodeFlood flood = graph.createNodeFlood();
 
         flood.add(graph.start());
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/cfs/FlowSensitiveReduction.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/cfs/FlowSensitiveReduction.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/cfs/FlowSensitiveReduction.java	Mon Sep 08 21:23:18 2014 +0200
@@ -22,24 +22,23 @@
  */
 package com.oracle.graal.phases.common.cfs;
 
+import static com.oracle.graal.api.meta.DeoptimizationAction.*;
+import static com.oracle.graal.api.meta.DeoptimizationReason.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
+
+import java.lang.reflect.*;
+
 import com.oracle.graal.api.meta.*;
-import com.oracle.graal.graph.Node;
+import com.oracle.graal.compiler.common.type.*;
+import com.oracle.graal.graph.*;
 import com.oracle.graal.nodes.*;
-import com.oracle.graal.nodes.calc.FloatingNode;
-import com.oracle.graal.nodes.calc.IsNullNode;
-import com.oracle.graal.nodes.extended.LoadHubNode;
-import com.oracle.graal.nodes.extended.NullCheckNode;
+import com.oracle.graal.nodes.calc.*;
+import com.oracle.graal.nodes.extended.*;
 import com.oracle.graal.nodes.java.*;
-import com.oracle.graal.compiler.common.type.IllegalStamp;
-import com.oracle.graal.nodes.type.StampTool;
-import com.oracle.graal.nodes.util.GraphUtil;
-import com.oracle.graal.phases.common.DeadCodeEliminationPhase;
-import com.oracle.graal.phases.tiers.PhaseContext;
-
-import java.lang.reflect.Modifier;
-
-import static com.oracle.graal.api.meta.DeoptimizationAction.InvalidateReprofile;
-import static com.oracle.graal.api.meta.DeoptimizationReason.*;
+import com.oracle.graal.nodes.type.*;
+import com.oracle.graal.nodes.util.*;
+import com.oracle.graal.phases.common.*;
+import com.oracle.graal.phases.tiers.*;
 
 /**
  * <p>
@@ -152,7 +151,7 @@
             for (PostponedDeopt postponed : postponedDeopts) {
                 postponed.doRewrite(falseConstant);
             }
-            new DeadCodeEliminationPhase().apply(graph);
+            new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
         }
         for (MethodCallTargetNode mcn : graph.getNodes().filter(MethodCallTargetNode.class)) {
             if (mcn.isAlive() && FlowUtil.lacksUsages(mcn)) {
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/inlining/info/elem/InlineableGraph.java	Mon Sep 08 21:23:18 2014 +0200
@@ -22,21 +22,20 @@
  */
 package com.oracle.graal.phases.common.inlining.info.elem;
 
+import static com.oracle.graal.compiler.common.GraalOptions.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
+
 import java.util.*;
 
-import com.oracle.graal.api.meta.Constant;
-import com.oracle.graal.api.meta.ResolvedJavaMethod;
-import com.oracle.graal.compiler.common.type.Stamp;
-import com.oracle.graal.debug.Debug;
+import com.oracle.graal.api.meta.*;
+import com.oracle.graal.compiler.common.type.*;
+import com.oracle.graal.debug.*;
 import com.oracle.graal.graph.*;
 import com.oracle.graal.nodes.*;
-import com.oracle.graal.phases.common.CanonicalizerPhase;
-import com.oracle.graal.phases.common.DeadCodeEliminationPhase;
-import com.oracle.graal.phases.common.cfs.FlowUtil;
-import com.oracle.graal.phases.common.inlining.InliningUtil;
-import com.oracle.graal.phases.tiers.HighTierContext;
-
-import static com.oracle.graal.compiler.common.GraalOptions.OptCanonicalizer;
+import com.oracle.graal.phases.common.*;
+import com.oracle.graal.phases.common.cfs.*;
+import com.oracle.graal.phases.common.inlining.*;
+import com.oracle.graal.phases.tiers.*;
 
 /**
  * <p>
@@ -245,7 +244,7 @@
             }
             assert newGraph.start().next() != null : "graph needs to be populated by the GraphBuilderSuite";
 
-            new DeadCodeEliminationPhase().apply(newGraph);
+            new DeadCodeEliminationPhase(OPTIONAL).apply(newGraph);
 
             if (OptCanonicalizer.getValue()) {
                 canonicalizer.apply(newGraph, context);
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/ReplacementsImpl.java
--- a/graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/ReplacementsImpl.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/ReplacementsImpl.java	Mon Sep 08 21:23:18 2014 +0200
@@ -25,6 +25,7 @@
 import static com.oracle.graal.api.meta.MetaUtil.*;
 import static com.oracle.graal.compiler.GraalCompiler.*;
 import static com.oracle.graal.compiler.common.GraalOptions.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 
 import java.lang.reflect.*;
 import java.util.*;
@@ -511,7 +512,7 @@
                     new CollapseFrameForSingleSideEffectPhase().apply(graph);
                     break;
             }
-            new DeadCodeEliminationPhase().apply(graph);
+            new DeadCodeEliminationPhase(REQUIRED).apply(graph);
         }
 
         /**
@@ -613,7 +614,7 @@
          */
         protected void afterInlining(StructuredGraph graph) {
             new NodeIntrinsificationPhase(providers, snippetReflection).apply(graph);
-            new DeadCodeEliminationPhase().apply(graph);
+            new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
             if (OptCanonicalizer.getValue()) {
                 new CanonicalizerPhase(true).apply(graph, new PhaseContext(providers, assumptions));
             }
@@ -686,7 +687,7 @@
                     end.disableSafepoint();
                 }
 
-                new DeadCodeEliminationPhase().apply(graph);
+                new DeadCodeEliminationPhase(REQUIRED).apply(graph);
             } catch (Throwable e) {
                 throw Debug.handle(e);
             }
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/SnippetTemplate.java
--- a/graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/SnippetTemplate.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/SnippetTemplate.java	Mon Sep 08 21:23:18 2014 +0200
@@ -26,6 +26,7 @@
 import static com.oracle.graal.compiler.common.GraalOptions.*;
 import static com.oracle.graal.debug.Debug.*;
 import static com.oracle.graal.graph.util.CollectionsAccess.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 import static com.oracle.graal.replacements.SnippetTemplate.AbstractTemplates.*;
 import static java.util.FormattableFlags.*;
 
@@ -670,7 +671,7 @@
             }
         }
 
-        new DeadCodeEliminationPhase().apply(snippetCopy);
+        new DeadCodeEliminationPhase(REQUIRED).apply(snippetCopy);
 
         assert checkAllVarargPlaceholdersAreDeleted(parameterCount, placeholders);
 
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/EffectsPhase.java
--- a/graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/EffectsPhase.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/EffectsPhase.java	Mon Sep 08 21:23:18 2014 +0200
@@ -23,6 +23,7 @@
 package com.oracle.graal.virtual.phases.ea;
 
 import static com.oracle.graal.debug.Debug.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 
 import java.util.*;
 
@@ -100,7 +101,7 @@
                     Debug.dump(graph, "after " + getName() + " iteration");
                 }
 
-                new DeadCodeEliminationPhase().apply(graph);
+                new DeadCodeEliminationPhase(REQUIRED).apply(graph);
 
                 Set<Node> changedNodes = listener.getNodes();
                 for (Node node : graph.getNodes()) {
diff -r 3c54a098455f -r 37d6d174bc40 graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/IterativeInliningPhase.java
--- a/graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/IterativeInliningPhase.java	Mon Sep 08 21:00:12 2014 +0200
+++ b/graal/com.oracle.graal.virtual/src/com/oracle/graal/virtual/phases/ea/IterativeInliningPhase.java	Mon Sep 08 21:23:18 2014 +0200
@@ -24,6 +24,7 @@
 
 import static com.oracle.graal.compiler.common.GraalOptions.*;
 import static com.oracle.graal.debug.Debug.*;
+import static com.oracle.graal.phases.common.DeadCodeEliminationPhase.Optionality.*;
 
 import java.util.*;
 
@@ -70,7 +71,7 @@
                 inlining.apply(graph, context);
                 progress |= inlining.getInliningCount() > 0;
 
-                new DeadCodeEliminationPhase().apply(graph);
+                new DeadCodeEliminationPhase(OPTIONAL).apply(graph);
 
                 boolean reduceOrEliminate = FlowSensitiveReduction.getValue() || ConditionalElimination.getValue();
                 if (reduceOrEliminate && OptCanonicalizer.getValue()) {