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package org.graalvm.compiler.hotspot.meta;

import org.graalvm.compiler.core.common.spi.JavaConstantFieldProvider;
import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
import org.graalvm.compiler.options.OptionValues;

import jdk.vm.ci.hotspot.HotSpotResolvedJavaField;
import jdk.vm.ci.meta.MetaAccessProvider;
import jdk.vm.ci.meta.ResolvedJavaField;
import jdk.vm.ci.meta.ResolvedJavaType;

Implements the default constant folding semantics for Java fields in the HotSpot VM.
/** * Implements the default constant folding semantics for Java fields in the HotSpot VM. */
public class HotSpotConstantFieldProvider extends JavaConstantFieldProvider { private final GraalHotSpotVMConfig config; public HotSpotConstantFieldProvider(GraalHotSpotVMConfig config, MetaAccessProvider metaAccess) { super(metaAccess); this.config = config; } @Override protected boolean isStableField(ResolvedJavaField field, ConstantFieldTool<?> tool) { if (!config.foldStableValues) { return false; } if (field.isStatic() && !isStaticFieldConstant(field, tool.getOptions())) { return false; } if (((HotSpotResolvedJavaField) field).isStable()) { return true; } return super.isStableField(field, tool); } @Override protected boolean isFinalField(ResolvedJavaField field, ConstantFieldTool<?> tool) { if (field.isStatic() && !isStaticFieldConstant(field, tool.getOptions())) { return false; } return super.isFinalField(field, tool); } private static final String SystemClassName = "Ljava/lang/System;"; protected boolean isStaticFieldConstant(ResolvedJavaField field, @SuppressWarnings("unused") OptionValues options) { ResolvedJavaType declaringClass = field.getDeclaringClass(); return declaringClass.isInitialized() && !declaringClass.getName().equals(SystemClassName); } }