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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package jdk.jfr.internal.instrument;

import java.util.ArrayList;
import java.util.List;

import jdk.internal.org.objectweb.asm.Label;
import jdk.internal.org.objectweb.asm.MethodVisitor;
import jdk.internal.org.objectweb.asm.Opcodes;
import jdk.internal.org.objectweb.asm.commons.LocalVariablesSorter;
import jdk.internal.org.objectweb.asm.commons.Remapper;
import jdk.internal.org.objectweb.asm.commons.SimpleRemapper;
import jdk.internal.org.objectweb.asm.tree.MethodNode;
import jdk.jfr.internal.LogLevel;
import jdk.jfr.internal.LogTag;
import jdk.jfr.internal.Logger;

Class responsible for finding the call to inline and inlining it. This code is heavily influenced by section 3.2.6 "Inline Method" in "Using ASM framework to implement common bytecode transformation patterns", E. Kuleshov, AOSD.07, March 2007, Vancouver, Canada. http://asm.ow2.org/index.html
/** * Class responsible for finding the call to inline and inlining it. * * This code is heavily influenced by section 3.2.6 "Inline Method" in * "Using ASM framework to implement common bytecode transformation patterns", * E. Kuleshov, AOSD.07, March 2007, Vancouver, Canada. * http://asm.ow2.org/index.html */
@Deprecated final class JIMethodCallInliner extends LocalVariablesSorter { private final String oldClass; private final String newClass; private final MethodNode inlineTarget; private final List<CatchBlock> blocks = new ArrayList<>(); private boolean inlining;
inlineTarget defines the method to inline and also contains the actual code to inline.
Params:
  • access –
  • desc –
  • mv –
  • inlineTarget –
  • oldClass –
  • newClass –
  • logger –
/** * inlineTarget defines the method to inline and also contains the actual * code to inline. * * @param access * @param desc * @param mv * @param inlineTarget * @param oldClass * @param newClass * @param logger */
public JIMethodCallInliner(int access, String desc, MethodVisitor mv, MethodNode inlineTarget, String oldClass, String newClass) { super(Opcodes.ASM7, access, desc, mv); this.oldClass = oldClass; this.newClass = newClass; this.inlineTarget = inlineTarget; Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.DEBUG, "MethodCallInliner: targetMethod=" + newClass + "." + inlineTarget.name + inlineTarget.desc); } @Override public void visitMethodInsn(int opcode, String owner, String name, String desc, boolean itf) { // Now we are looking at method call in the source method if (!shouldBeInlined(owner, name, desc)) { // If this method call should not be inlined, just keep it mv.visitMethodInsn(opcode, owner, name, desc, itf); return; } // If the call should be inlined, we create a MethodInliningAdapter // The MIA will walk the instructions in the inlineTarget and add them // to the current method, doing the necessary name remappings. Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.DEBUG, "Inlining call to " + name + desc); Remapper remapper = new SimpleRemapper(oldClass, newClass); Label end = new Label(); inlining = true; inlineTarget.instructions.resetLabels(); JIMethodInliningAdapter mia = new JIMethodInliningAdapter(this, end, opcode == Opcodes.INVOKESTATIC ? Opcodes.ACC_STATIC : 0, desc, remapper); inlineTarget.accept(mia); inlining = false; super.visitLabel(end); }
Determine if the method should be inlined or not.
/** * Determine if the method should be inlined or not. */
private boolean shouldBeInlined(String owner, String name, String desc) { return inlineTarget.desc.equals(desc) && inlineTarget.name.equals(name) && owner.equals(newClass.replace('.', '/')); } @Override public void visitTryCatchBlock(Label start, Label end, Label handler, String type) { if (!inlining) { // try-catch blocks are saved here and replayed at the end // of the method (in visitMaxs) blocks.add(new CatchBlock(start, end, handler, type)); } else { super.visitTryCatchBlock(start, end, handler, type); } } @Override public void visitMaxs(int stack, int locals) { for (CatchBlock b : blocks) { super.visitTryCatchBlock(b.start, b.end, b.handler, b.type); } super.visitMaxs(stack, locals); } static final class CatchBlock { final Label start; final Label end; final Label handler; final String type; CatchBlock(Label start, Label end, Label handler, String type) { this.start = start; this.end = end; this.handler = handler; this.type = type; } } }