[GR-43361] [GR-50205] Whole-Program Sparse Conditional Constant Propagation

PullRequest: graal/18609

Author: d-kozak

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/AnalysisObjectScanningObserver.java

@@ -44,14 +44,15 @@ public AnalysisObjectScanningObserver(BigBang bb) {
 
     @Override
     public boolean forRelocatedPointerFieldValue(JavaConstant receiver, AnalysisField field, JavaConstant fieldValue, ScanReason reason) {
-        if (!field.isWritten()) {
-            return field.registerAsWritten(reason);
-        }
+        var changed = false;
         if (fieldValue.isNonNull()) {
             FieldTypeFlow fieldTypeFlow = getFieldTypeFlow(field, receiver);
-            return fieldTypeFlow.addState(getAnalysis(), TypeState.anyPrimitiveState());
+            changed = fieldTypeFlow.addState(getAnalysis(), TypeState.anyPrimitiveState());
         }
-        return false;
+        if (!field.isWritten()) {
+            changed |= field.registerAsWritten(reason);
+        }
+        return changed;
     }
 
     @Override

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/PointsToAnalysis.java

@@ -102,6 +102,9 @@ public abstract class PointsToAnalysis extends AbstractAnalysisEngine {
      * immediately represented as {@link com.oracle.graal.pointsto.flow.AnyPrimitiveSourceTypeFlow}.
      */
     private final boolean trackPrimitiveValues;
+    private final AnalysisType longType;
+    private final AnalysisType voidType;
+    private final boolean usePredicates;
     private AnyPrimitiveSourceTypeFlow anyPrimitiveSourceTypeFlow;
 
     protected final boolean trackTypeFlowInputs;
@@ -121,10 +124,15 @@ public PointsToAnalysis(OptionValues options, AnalysisUniverse universe, HostVM
                     ClassInclusionPolicy classInclusionPolicy) {
         super(options, universe, hostVM, metaAccess, snippetReflectionProvider, constantReflectionProvider, wordTypes, unsupportedFeatures, debugContext, timerCollection, classInclusionPolicy);
         this.typeFlowTimer = timerCollection.createTimer("(typeflow)");
-        this.trackPrimitiveValues = PointstoOptions.TrackPrimitiveValues.getValue(options);
-        this.anyPrimitiveSourceTypeFlow = new AnyPrimitiveSourceTypeFlow(null, null);
 
         this.objectType = metaAccess.lookupJavaType(Object.class);
+        this.longType = metaAccess.lookupJavaType(long.class);
+        this.voidType = metaAccess.lookupJavaType(void.class);
+
+        this.trackPrimitiveValues = PointstoOptions.TrackPrimitiveValues.getValue(options);
+        this.usePredicates = PointstoOptions.UsePredicates.getValue(options);
+        this.anyPrimitiveSourceTypeFlow = new AnyPrimitiveSourceTypeFlow(null, longType);
+        this.anyPrimitiveSourceTypeFlow.enableFlow(null);
         /*
          * Make sure the all-instantiated type flow is created early. We do not have any
          * instantiated types yet, so the state is empty at first.
@@ -270,6 +278,14 @@ public AnalysisType getObjectType() {
         return universe.objectType();
     }
 
+    public AnalysisType getLongType() {
+        return longType;
+    }
+
+    public AnalysisType getVoidType() {
+        return voidType;
+    }
+
     public AnalysisType getObjectArrayType() {
         return metaAccess.lookupJavaType(Object[].class);
     }
@@ -538,6 +554,10 @@ public boolean trackPrimitiveValues() {
         return trackPrimitiveValues;
     }
 
+    public boolean usePredicates() {
+        return usePredicates;
+    }
+
     public interface TypeFlowRunnable extends DebugContextRunnable {
         TypeFlow<?> getTypeFlow();
     }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/api/PointstoOptions.java

@@ -39,6 +39,9 @@ public class PointstoOptions {
     @Option(help = "Track primitive values using the infrastructure of points-to analysis.")//
     public static final OptionKey<Boolean> TrackPrimitiveValues = new OptionKey<>(false);
 
+    @Option(help = "Use predicates in points-to analysis.")//
+    public static final OptionKey<Boolean> UsePredicates = new OptionKey<>(false);
+
     @Option(help = "Use experimental Reachability Analysis instead of points-to.")//
     public static final OptionKey<Boolean> UseExperimentalReachabilityAnalysis = new OptionKey<>(false);
 

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AbstractSpecialInvokeTypeFlow.java

@@ -45,6 +45,11 @@ protected AbstractSpecialInvokeTypeFlow(PointsToAnalysis bb, MethodFlowsGraph me
         super(bb, methodFlows, original);
     }
 
+    @Override
+    protected void onFlowEnabled(PointsToAnalysis bb) {
+        bb.postTask(() -> onObservedUpdate(bb));
+    }
+
     @Override
     public boolean addState(PointsToAnalysis bb, TypeState add, boolean postFlow) {
         throw AnalysisError.shouldNotReachHere("The SpecialInvokeTypeFlow should not be updated directly.");

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AbstractStaticInvokeTypeFlow.java

@@ -41,17 +41,6 @@ protected AbstractStaticInvokeTypeFlow(PointsToAnalysis bb, MethodFlowsGraph met
         super(bb, methodFlows, original);
     }
 
-    @Override
-    public void initFlow(PointsToAnalysis bb) {
-        /* Trigger the update for static invokes, there is no receiver to trigger it. */
-        bb.postFlow(this);
-    }
-
-    @Override
-    public boolean needsInitialization() {
-        return true;
-    }
-
     @Override
     public String toString() {
         return "StaticInvoke<" + targetMethod.format("%h.%n") + ">" + ":" + getState();

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AbstractVirtualInvokeTypeFlow.java

@@ -87,6 +87,11 @@ public final boolean isDirectInvoke() {
         return false;
     }
 
+    @Override
+    protected void onFlowEnabled(PointsToAnalysis bb) {
+        bb.postTask(() -> onObservedUpdate(bb));
+    }
+
     @Override
     public boolean addState(PointsToAnalysis bb, TypeState add, boolean postFlow) {
         throw AnalysisError.shouldNotReachHere("The VirtualInvokeTypeFlow should not be updated directly.");

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AllInstantiatedTypeFlow.java

@@ -32,11 +32,11 @@
  * of the all assignable types. This flow is used for uses that need to be notified when a sub-type
  * of a specific type is marked as instantiated, e.g., a saturated field access type flow needs to
  * be notified when a sub-type of its declared type is marked as instantiated.
- *
+ * <p>
  * Note this flow should only be instantiated within AnalysisType. When needed, this flow should be
  * retrieved via calling {@link AnalysisType#getTypeFlow}.
  */
-public final class AllInstantiatedTypeFlow extends TypeFlow<AnalysisType> {
+public final class AllInstantiatedTypeFlow extends TypeFlow<AnalysisType> implements GlobalFlow {
 
     public AllInstantiatedTypeFlow(AnalysisType declaredType, boolean canBeNull) {
         super(declaredType, declaredType, canBeNull);

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AlwaysEnabledPredicateFlow.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2024, 2024, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.graal.pointsto.flow;
+
+import com.oracle.graal.pointsto.typestate.TypeState;
+
+import jdk.vm.ci.code.BytecodePosition;
+
+/**
+ * Always-enabled global flow that is used as a predicate before any other suitable flow is
+ * available.
+ */
+public class AlwaysEnabledPredicateFlow extends TypeFlow<BytecodePosition> implements GlobalFlow {
+
+    public AlwaysEnabledPredicateFlow() {
+        /* We use any primitive state here just to make sure the state is always non-empty. */
+        super(TypeState.anyPrimitiveState());
+    }
+}

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/AnyPrimitiveSourceTypeFlow.java

@@ -24,18 +24,47 @@
  */
 package com.oracle.graal.pointsto.flow;
 
+import com.oracle.graal.pointsto.PointsToAnalysis;
 import com.oracle.graal.pointsto.meta.AnalysisType;
 import com.oracle.graal.pointsto.typestate.TypeState;
 
 import jdk.vm.ci.code.BytecodePosition;
 
 /**
  * Produces AnyPrimitive state that leads to immediate saturation of all uses. Used to represent any
- * operation that is not modeled by the analysis.
+ * operation on primitives that is not explicitly modeled by the analysis.
+ * </p>
+ * This flow can be either global (source == null) or local (source != null).
  */
 public final class AnyPrimitiveSourceTypeFlow extends TypeFlow<BytecodePosition> implements PrimitiveFlow {
 
     public AnyPrimitiveSourceTypeFlow(BytecodePosition source, AnalysisType type) {
         super(source, type, TypeState.anyPrimitiveState());
     }
+
+    private AnyPrimitiveSourceTypeFlow(MethodFlowsGraph methodFlows, AnyPrimitiveSourceTypeFlow original) {
+        super(original, methodFlows, TypeState.anyPrimitiveState());
+    }
+
+    @Override
+    public TypeFlow<BytecodePosition> copy(PointsToAnalysis bb, MethodFlowsGraph methodFlows) {
+        assert isLocal() : "Global flow should never be cloned: " + this;
+        return new AnyPrimitiveSourceTypeFlow(methodFlows, this);
+    }
+
+    private boolean isLocal() {
+        return source != null;
+    }
+
+    @Override
+    public boolean canSaturate() {
+        /*
+         * AnyPrimitiveSourceTypeFlow can be used as a global flow that should always propagate
+         * values. The global version can be identified be having source == null, and it should
+         * never saturate.
+         * 
+         * The local versions of this flow have a concrete bytecode position and can saturate.
+         */
+        return isLocal();
+    }
 }

substratevm/src/com.oracle.graal.pointsto/src/com/oracle/graal/pointsto/flow/ArrayElementsTypeFlow.java

@@ -34,7 +34,7 @@
 /**
  * This class is used to model the elements type flow for array objects.
  */
-public class ArrayElementsTypeFlow extends TypeFlow<AnalysisType> {
+public class ArrayElementsTypeFlow extends TypeFlow<AnalysisType> implements GlobalFlow {
 
     /** The array object. */
     private final AnalysisObject object;