[GR-48573] Deopt in Unsafe allocate based on jvmti _should_notify_object_alloc.

PullRequest: graal/16276

Author: rmosaner

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/hotspot/GraalHotSpotVMConfig.java

@@ -402,6 +402,13 @@ public long defaultPrototypeMarkWord() {
      */
     public final int maxOopMapStackOffset = getFieldValue("CompilerToVM::Data::_max_oop_map_stack_offset", Integer.class, "int");
 
+    /**
+     * Address of {@code _should_notify_object_alloc}, which, if non-zero, modifies the intrinsic
+     * for {@code Unsafe.allocateInstance} to deopt when
+     * {@code *shouldNotifyObjectAllocAddress != 0}.
+     */
+    public final long shouldNotifyObjectAllocAddress = getFieldValue("CompilerToVM::Data::_should_notify_object_alloc", Long.class, "int*", 0L, JDK >= 23);
+
     // G1 Collector Related Values.
     public final byte dirtyCardValue = getConstant("CardTable::dirty_card", Byte.class);
     public final byte g1YoungCardValue = getConstant("G1CardTable::g1_young_gen", Byte.class);

compiler/src/jdk.graal.compiler/src/jdk/graal/compiler/hotspot/meta/HotSpotGraphBuilderPlugins.java

@@ -89,6 +89,7 @@
 import jdk.graal.compiler.nodes.ConstantNode;
 import jdk.graal.compiler.nodes.EndNode;
 import jdk.graal.compiler.nodes.FieldLocationIdentity;
+import jdk.graal.compiler.nodes.FixedGuardNode;
 import jdk.graal.compiler.nodes.IfNode;
 import jdk.graal.compiler.nodes.LogicNode;
 import jdk.graal.compiler.nodes.MergeNode;
@@ -169,6 +170,8 @@
 import jdk.vm.ci.code.Architecture;
 import jdk.vm.ci.code.TargetDescription;
 import jdk.vm.ci.meta.ConstantReflectionProvider;
+import jdk.vm.ci.meta.DeoptimizationAction;
+import jdk.vm.ci.meta.DeoptimizationReason;
 import jdk.vm.ci.meta.JavaKind;
 import jdk.vm.ci.meta.MetaAccessProvider;
 import jdk.vm.ci.meta.ResolvedJavaField;
@@ -244,7 +247,7 @@ public void run() {
                 registerBigIntegerPlugins(invocationPlugins, config, replacements);
                 registerSHAPlugins(invocationPlugins, config, replacements);
                 registerBase64Plugins(invocationPlugins, config, metaAccess, replacements);
-                registerUnsafePlugins(invocationPlugins, replacements);
+                registerUnsafePlugins(invocationPlugins, replacements, config);
                 StandardGraphBuilderPlugins.registerInvocationPlugins(snippetReflection, invocationPlugins, replacements, true, false, true, graalRuntime.getHostProviders().getLowerer());
                 registerArrayPlugins(invocationPlugins, replacements, config);
                 registerStringPlugins(invocationPlugins, replacements, wordTypes, foreignCalls, config);
@@ -479,7 +482,7 @@ public boolean apply(GraphBuilderContext b, ResolvedJavaMethod targetMethod, Rec
         });
     }
 
-    private static void registerUnsafePlugins(InvocationPlugins plugins, Replacements replacements) {
+    private static void registerUnsafePlugins(InvocationPlugins plugins, Replacements replacements, GraalHotSpotVMConfig config) {
         Registration r = new Registration(plugins, "jdk.internal.misc.Unsafe", replacements);
         r.register(new InvocationPlugin("copyMemory0", Receiver.class, Object.class, long.class, Object.class, long.class, long.class) {
             @Override
@@ -492,6 +495,19 @@ public boolean apply(GraphBuilderContext b, ResolvedJavaMethod targetMethod, Rec
         r.register(new InvocationPlugin("allocateInstance", Receiver.class, Class.class) {
             @Override
             public boolean apply(GraphBuilderContext b, ResolvedJavaMethod targetMethod, Receiver unsafe, ValueNode clazz) {
+                if (b.getGraph().getProfilingInfo() != null && b.getGraph().getProfilingInfo().getDeoptimizationCount(DeoptimizationReason.RuntimeConstraint) > 20) {
+                    // Heuristic to prevent deoptimization loops.
+                    return false;
+                }
+                if (config.shouldNotifyObjectAllocAddress != 0) {
+                    try (HotSpotInvocationPluginHelper helper = new HotSpotInvocationPluginHelper(b, targetMethod, config)) {
+                        OffsetAddressNode address = OffsetAddressNode.create(helper.asWord(config.shouldNotifyObjectAllocAddress));
+                        ValueNode shouldPostVMObjectAlloc = b.add(new JavaReadNode(JavaKind.Int, address, LocationIdentity.ANY_LOCATION, BarrierType.NONE, MemoryOrderMode.PLAIN, false));
+                        LogicNode testShouldPostVMObjectAlloc = IntegerEqualsNode.create(shouldPostVMObjectAlloc, ConstantNode.forInt(0), NodeView.DEFAULT);
+                        FixedGuardNode guard = new FixedGuardNode(testShouldPostVMObjectAlloc, DeoptimizationReason.RuntimeConstraint, DeoptimizationAction.InvalidateRecompile);
+                        b.add(guard);
+                    }
+                }
                 /* Emits a null-check for the otherwise unused receiver. */
                 unsafe.get(true);
                 /*