List of usage examples for org.objectweb.asm.tree JumpInsnNode clone
@Override
public AbstractInsnNode clone(final Map<LabelNode, LabelNode> clonedLabels)
From source file:pl.clareo.coroutines.core.MethodTransformer.java
License:Apache License
@SuppressWarnings("unchecked") MethodNode transform(String coroutineName, boolean generateDebugCode) { MethodNode transformedMethod = new MethodNode(); transformedMethod.access = ACC_PUBLIC | ACC_FINAL | (method.access & ACC_STATIC); transformedMethod.name = coroutineName; transformedMethod.desc = COROUTINE_METHOD_DESCRIPTOR; transformedMethod.exceptions = method.exceptions; final InsnList newCode = transformedMethod.instructions; Analyzer analyzer = new Analyzer(new BasicInterpreter() { @Override// w w w.j a v a 2s . c om public Value binaryOperation(AbstractInsnNode insn, Value value1, Value value2) throws AnalyzerException { if (insn.getOpcode() == AALOAD) { return new BasicValue(((BasicValue) value1).getType().getElementType()); } return super.binaryOperation(insn, value1, value2); }; @Override public Value merge(Value v, Value w) { if (v == NULL_VALUE) { BasicValue w1 = (BasicValue) w; if (w1.isReference()) { return w1; } } if (w == NULL_VALUE) { BasicValue v1 = (BasicValue) v; if (v1.isReference()) return v1; } if (!v.equals(w)) { BasicValue v1 = (BasicValue) v; BasicValue w1 = (BasicValue) w; if (v1.isReference() & w1.isReference()) { Class<?> c1; Class<?> c2; try { c1 = MethodTransformer.getClass(v1); c2 = MethodTransformer.getClass(w1); } catch (ClassNotFoundException e) { throw new CoroutineGenerationException( "It was needed to load a class during transformation process but loading unexpectedly failed", e); } if (c1.isAssignableFrom(c2)) { return v; } if (c2.isAssignableFrom(c1)) { return w; } } } else { return v; } return BasicValue.UNINITIALIZED_VALUE; } @Override public Value newValue(Type type) { if (type != null) { int typeSort = type.getSort(); switch (typeSort) { case Type.VOID: return NULL_VALUE; case Type.BOOLEAN: case Type.CHAR: case Type.BYTE: case Type.SHORT: case Type.INT: return BasicValue.INT_VALUE; case Type.FLOAT: return BasicValue.FLOAT_VALUE; case Type.LONG: return BasicValue.LONG_VALUE; case Type.DOUBLE: return BasicValue.DOUBLE_VALUE; case Type.ARRAY: case Type.OBJECT: if (type.getInternalName().equals("null")) { return NULL_VALUE; } return new BasicValue(type); default: throw new Error("Internal error"); } } return BasicValue.UNINITIALIZED_VALUE; } }); Frame[] frames; try { frames = analyzer.analyze(methodOwner, method); } catch (AnalyzerException e) { throw new CoroutineGenerationException(e); } InsnList code = method.instructions; final List<Integer> yields = new ArrayList<Integer>(8); /* * Copy instructions patching variable indexes and frames, remember * yield indexes */ int ic = 0; Iterator<AbstractInsnNode> i = code.iterator(); while (i.hasNext()) { AbstractInsnNode insn = i.next(); switch (insn.getType()) { case AbstractInsnNode.FRAME: FrameNode frame = (FrameNode) insn.clone(labelsMap); // update values if (frame.type == F_FULL) { if (isStatic) { frame.local.addAll(0, argsStackMapList); } else { frame.local.addAll(1, argsStackMapList); } } newCode.add(frame); break; case AbstractInsnNode.IINC_INSN: IincInsnNode iinc = (IincInsnNode) insn.clone(labelsMap); iinc.var += variableIndexOffset; newCode.add(iinc); break; case AbstractInsnNode.INSN: switch (insn.getOpcode()) { case DRETURN: case FRETURN: case IRETURN: case LRETURN: case ARETURN: case RETURN: newCode.add(new InsnNode(POP)); newCode.add(throwex("java/util/NoSuchElementException")); break; default: newCode.add(insn.clone(labelsMap)); } break; case AbstractInsnNode.JUMP_INSN: if (insn.getOpcode() == JSR) { throw new CoroutineGenerationException("<jsr> not allowed"); } JumpInsnNode jump = (JumpInsnNode) insn; LabelNode target = jump.label; if (!labelsMap.containsKey(target)) { labelsMap.put(target, new LabelNode()); } newCode.add(jump.clone(labelsMap)); break; case AbstractInsnNode.LABEL: if (!labelsMap.containsKey(insn)) { labelsMap.put((LabelNode) insn, new LabelNode()); } newCode.add(insn.clone(labelsMap)); break; case AbstractInsnNode.METHOD_INSN: if (insn.getOpcode() == INVOKESTATIC) { MethodInsnNode method = (MethodInsnNode) insn; if (method.owner.equals(COROUTINES_NAME)) { String methodName = method.name; if (methodName.equals("_")) { /* * a call to artificial CoIterator, since it is * not needed after instrumentation we replace * it with null. This null will be popped by * corresponding ARETURN. Stack is not changed */ newCode.add(new InsnNode(ACONST_NULL)); break; } if (methodName.equals("yield")) { /* * a call to yield - core of coroutine * processing */ yields.add(ic); } } } newCode.add(insn.clone(labelsMap)); break; case AbstractInsnNode.VAR_INSN: if (insn.getOpcode() == RET) { throw new CoroutineGenerationException("<ret> not allowed"); } VarInsnNode var = (VarInsnNode) insn.clone(labelsMap); if (var.var != 0 || isStatic) { var.var += variableIndexOffset; } newCode.add(var); break; default: newCode.add(insn.clone(labelsMap)); break; } ic += 1; } /* * patch yields in transformed code */ final List<LabelNode> gotos = new ArrayList<LabelNode>(9); final Set<TryCatchBlockNode> patchedTryCatchBlocks = new HashSet<TryCatchBlockNode>(); int yieldIndex = 0; i = newCode.iterator(); while (i.hasNext()) { AbstractInsnNode insn = i.next(); /* * track locals */ int insnType = insn.getType(); if (insnType == AbstractInsnNode.VAR_INSN) { int opcode = insn.getOpcode(); if (opcode == ASTORE || opcode == DSTORE || opcode == LSTORE || opcode == ISTORE || opcode == FSTORE) { int varIndex = ((VarInsnNode) insn).var - variableIndexOffset; finals[varIndex] = false; } continue; } /* * track line numbers */ if (insnType == AbstractInsnNode.LINE) { lineNumber = ((LineNumberNode) insn).line; continue; } if (insnType != AbstractInsnNode.METHOD_INSN) { continue; } MethodInsnNode method = (MethodInsnNode) insn; if (!method.owner.equals(COROUTINES_NAME) || !method.name.equals("yield")) { continue; } InsnList yieldCode = new InsnList(); int index = yields.get(yieldIndex); Frame f = frames[index]; /* * a) operand on the top of stack is passed to the caller, we will * save it in 'in' parameter OR there is nothing to be passed to the * caller in case of yield() overload */ boolean yieldWithArgument = Type.getArgumentTypes(method.desc).length != 0; boolean nonemptyStack; Type[] stackContents = null; int stackTop = 0; if (yieldWithArgument) { yieldCode.add(input(getStackTop(f))); nonemptyStack = f.getStackSize() > 1; stackTop = 1; } else { nonemptyStack = f.getStackSize() > 0; } /* * b) save remaining stack */ if (nonemptyStack) { stackContents = getStackContents(f); // sanitize stack for (Type t : stackContents) { if (t == null) { throw new CoroutineGenerationException( "It is not possible to yield with uninitialized memory on the stack. Probably you use construct such as: new A(..,yield,..). Please move this yield call out of constructor"); } } yieldCode.add(savestack(frame, stackContents, stackTop)); } /* * c) save locals and state */ Type[] locals = getLocals(f); yieldCode.add(saveLocals(locals)); yieldCode.add(new VarInsnNode(ALOAD, frame)); yieldCode.add(makeInt(++yieldIndex)); yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "setState", "(I)V")); /* * d) jump to exit - in debug mode save line number */ if (generateDebugCode) { yieldCode.add(new VarInsnNode(ALOAD, frame)); yieldCode.add(makeInt(lineNumber)); yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "setLineOfCode", "(I)V")); } yieldCode.add(new JumpInsnNode(GOTO, yieldLabel)); /* * e) fix jump from switch statement */ LabelNode jump = new LabelNode(); gotos.add(jump); yieldCode.add(jump); yieldCode.add(emitCleanFrame()); /* * f) check if exit condition occurs, load locals, restore stack and * stack map */ yieldCode.add(new VarInsnNode(ALOAD, frame)); yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "isCoroutineClosed", "()Z")); LabelNode continueHere = new LabelNode(); yieldCode.add(new JumpInsnNode(IFEQ, continueHere)); yieldCode.add(throwex(COROUTINE_EXIT_EXCEPTION)); yieldCode.add(continueHere); yieldCode.add(new FrameNode(F_SAME, 0, EMPTY_LOCALS, 0, EMPTY_STACK)); /* * find previous frame node, load locals then emit new frame node * and load rest */ FrameNode prevFrame = findPreviousFrame(code.get(index)); Type[] prevLocals; if (prevFrame != null) { Frame oldFrame = frames[code.indexOf(prevFrame)]; prevLocals = getLocals(oldFrame); } else { prevLocals = getLocals(frames[0]); } yieldCode.add(restoreLocals(prevLocals)); FrameNode frameNode = mergeFrames(getFrameTypes(prevLocals), null); if (frameNode.type != F_SAME) { // bug fix - when no locals are restored and the stack is empty // two frames are collapsed yieldCode.add(frameNode); } if (nonemptyStack) { yieldCode.add(loadstack(frame, stackContents, stackTop)); } // restore temp locals in scope yieldCode.add(restoreLocals(diff(locals, prevLocals))); /* * push "sent" value */ yieldCode.add(new VarInsnNode(ALOAD, out)); newCode.insertBefore(method, yieldCode); /* * patch try catch blocks */ List<TryCatchBlockNode> tryCatchBlocks = analyzer.getHandlers(index); if (tryCatchBlocks != null) { for (TryCatchBlockNode tryCatchBlock : tryCatchBlocks) { if (!patchedTryCatchBlocks.contains(tryCatchBlock)) { LabelNode handler = tryCatchBlock.handler; InsnList handlerPatch = new InsnList(); String exceptionType = tryCatchBlock.type == null ? "java/lang/Throwable" : tryCatchBlock.type; FrameNode catchFrame = emitCatchFrame(exceptionType); handlerPatch.add(catchFrame); Type[] ls = getLocals(frames[code.indexOf(handler)]); handlerPatch.add(restoreLocals(ls)); handlerPatch.add( mergeFrames(getFrameTypes(ls), new Type[] { Type.getObjectType(exceptionType) })); patchedTryCatchBlocks.add(tryCatchBlock); AbstractInsnNode newHandler = labelsMap.get(handler); // remove "real" frame since it is not needed now newCode.remove(findNextFrame(newHandler)); newCode.insert(newHandler, handlerPatch); } } } newCode.remove(method); } /* * copy local variables (wath out for indices change) and try catch * blocks to new method (clone) */ List<TryCatchBlockNode> tryCatchBlocks = method.tryCatchBlocks; if (!tryCatchBlocks.isEmpty()) { transformedMethod.tryCatchBlocks = new ArrayList<TryCatchBlockNode>(tryCatchBlocks.size()); for (TryCatchBlockNode tryCatchBlock : tryCatchBlocks) { transformedMethod.tryCatchBlocks.add( new TryCatchBlockNode(labelsMap.get(tryCatchBlock.start), labelsMap.get(tryCatchBlock.end), labelsMap.get(tryCatchBlock.handler), tryCatchBlock.type)); } } if (method.localVariables != null) { List<LocalVariableNode> localVariables = method.localVariables; List<LocalVariableNode> newLocalVariables = new ArrayList<LocalVariableNode>(localVariables.size()); for (LocalVariableNode localVariable : localVariables) { int newIndex = localVariable.index; if (newIndex != 0 || isStatic) { newIndex += variableIndexOffset; } newLocalVariables .add(new LocalVariableNode(localVariable.name, localVariable.desc, localVariable.signature, labelsMap.get(localVariable.start), labelsMap.get(localVariable.end), newIndex)); } transformedMethod.localVariables = newLocalVariables; } newCode.insert(codeBefore(gotos)); newCode.add(codeAfter()); return transformedMethod; }