--- /dev/null 2017-01-22 10:16:57.869617664 -0800 +++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements/src/org/graalvm/compiler/replacements/classfile/ClassfileBytecodeProvider.java 2017-02-15 17:09:12.347361824 -0800 @@ -0,0 +1,186 @@ +/* + * Copyright (c) 2016, 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. + * + * 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 org.graalvm.compiler.replacements.classfile; + +import static org.graalvm.compiler.core.common.util.ModuleAPI.getModule; +import static org.graalvm.compiler.core.common.util.ModuleAPI.getResourceAsStream; +import static org.graalvm.compiler.core.common.util.Util.JAVA_SPECIFICATION_VERSION; + +import java.io.DataInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.lang.instrument.Instrumentation; +import java.util.HashMap; +import java.util.Map; + +import org.graalvm.compiler.api.replacements.SnippetReflectionProvider; +import org.graalvm.compiler.bytecode.Bytecode; +import org.graalvm.compiler.bytecode.BytecodeProvider; + +import jdk.vm.ci.meta.JavaKind; +import jdk.vm.ci.meta.MetaAccessProvider; +import jdk.vm.ci.meta.ResolvedJavaField; +import jdk.vm.ci.meta.ResolvedJavaMethod; +import jdk.vm.ci.meta.ResolvedJavaType; + +/** + * A {@link BytecodeProvider} that provides bytecode properties of a {@link ResolvedJavaMethod} as + * parsed from a class file. This avoids all {@linkplain Instrumentation instrumentation} and any + * bytecode rewriting performed by the VM. + * + * This mechanism retrieves class files based on the name and {@link ClassLoader} of existing + * {@link Class} instances. It bypasses all VM parsing and verification of the class file and + * assumes the class files are well formed. As such, it should only be used for classes from a + * trusted source such as the boot class (or module) path. + * + * A combination of {@link Class#forName(String)} and an existing {@link MetaAccessProvider} is used + * to resolve constant pool references. This opens up the opportunity for linkage errors if the + * referee is structurally changed through redefinition (e.g., a referred to method is renamed or + * deleted). This will result in an appropriate {@link LinkageError} being thrown. The only way to + * avoid this is to have a completely isolated {@code jdk.vm.ci.meta} implementation for parsing + * snippet/intrinsic bytecodes. + */ +public final class ClassfileBytecodeProvider implements BytecodeProvider { + + private final ClassLoader loader; + private final Map, Classfile> classfiles = new HashMap<>(); + private final Map> classes = new HashMap<>(); + final MetaAccessProvider metaAccess; + final SnippetReflectionProvider snippetReflection; + + public ClassfileBytecodeProvider(MetaAccessProvider metaAccess, SnippetReflectionProvider snippetReflection) { + this.metaAccess = metaAccess; + this.snippetReflection = snippetReflection; + ClassLoader cl = getClass().getClassLoader(); + this.loader = cl == null ? ClassLoader.getSystemClassLoader() : cl; + } + + @Override + public Bytecode getBytecode(ResolvedJavaMethod method) { + Classfile classfile = getClassfile(resolveToClass(method.getDeclaringClass().getName())); + return classfile.getCode(method.getName(), method.getSignature().toMethodDescriptor()); + } + + @Override + public boolean supportsInvokedynamic() { + return false; + } + + @Override + public boolean shouldRecordMethodDependencies() { + return false; + } + + private static InputStream getClassfileAsStream(Class c) { + String classfilePath = c.getName().replace('.', '/') + ".class"; + if (JAVA_SPECIFICATION_VERSION >= 9) { + Object module = getModule.invoke(c); + return getResourceAsStream.invoke(module, classfilePath); + } else { + ClassLoader cl = c.getClassLoader(); + if (cl == null) { + return ClassLoader.getSystemResourceAsStream(classfilePath); + } + return cl.getResourceAsStream(classfilePath); + } + } + + /** + * Gets a {@link Classfile} created by parsing the class file bytes for {@code c}. + * + * @throws NoClassDefFoundError if the class file cannot be found + */ + private synchronized Classfile getClassfile(Class c) { + assert !c.isPrimitive() && !c.isArray() : c; + Classfile classfile = classfiles.get(c); + if (classfile == null) { + try { + ResolvedJavaType type = metaAccess.lookupJavaType(c); + InputStream in = getClassfileAsStream(c); + if (in != null) { + DataInputStream stream = new DataInputStream(in); + classfile = new Classfile(type, stream, this); + classfiles.put(c, classfile); + return classfile; + } + throw new NoClassDefFoundError(c.getName()); + } catch (IOException e) { + throw (NoClassDefFoundError) new NoClassDefFoundError(c.getName()).initCause(e); + } + } + return classfile; + } + + synchronized Class resolveToClass(String descriptor) { + Class c = classes.get(descriptor); + if (c == null) { + if (descriptor.length() == 1) { + c = JavaKind.fromPrimitiveOrVoidTypeChar(descriptor.charAt(0)).toJavaClass(); + } else { + int dimensions = 0; + while (descriptor.charAt(dimensions) == '[') { + dimensions++; + } + String name; + if (dimensions == 0 && descriptor.startsWith("L") && descriptor.endsWith(";")) { + name = descriptor.substring(1, descriptor.length() - 1).replace('/', '.'); + } else { + name = descriptor.replace('/', '.'); + } + try { + c = Class.forName(name, true, loader); + classes.put(descriptor, c); + } catch (ClassNotFoundException e) { + throw new NoClassDefFoundError(descriptor); + } + } + } + return c; + } + + static ResolvedJavaMethod findMethod(ResolvedJavaType type, String name, String descriptor, boolean isStatic) { + if (isStatic && name.equals("")) { + ResolvedJavaMethod method = type.getClassInitializer(); + if (method != null) { + return method; + } + } + ResolvedJavaMethod[] methodsToSearch = name.equals("") ? type.getDeclaredConstructors() : type.getDeclaredMethods(); + for (ResolvedJavaMethod method : methodsToSearch) { + if (method.isStatic() == isStatic && method.getName().equals(name) && method.getSignature().toMethodDescriptor().equals(descriptor)) { + return method; + } + } + return null; + } + + static ResolvedJavaField findField(ResolvedJavaType type, String name, String fieldType, boolean isStatic) { + ResolvedJavaField[] fields = isStatic ? type.getStaticFields() : type.getInstanceFields(false); + for (ResolvedJavaField field : fields) { + if (field.getName().equals(name) && field.getType().getName().equals(fieldType)) { + return field; + } + } + return null; + } +}