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diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/AnalyzerExt.java b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/AnalyzerExt.java
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+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/AnalyzerExt.java
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+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.codeInspection.bytecodeAnalysis.asm;
+
+import org.jetbrains.org.objectweb.asm.Opcodes;
+import org.jetbrains.org.objectweb.asm.Type;
+import org.jetbrains.org.objectweb.asm.tree.*;
+import org.jetbrains.org.objectweb.asm.tree.analysis.*;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Extended version of {@link org.jetbrains.org.objectweb.asm.tree.analysis.Analyzer}.
+ * It handles frames <b>and</b> additional data.
+ *
+ * @author lambdamix
+ */
+public class AnalyzerExt<V extends Value, Data, MyInterpreter extends Interpreter<V> & InterpreterExt<Data>> implements Opcodes {
+
+ private final MyInterpreter interpreter;
+
+ private int n;
+
+ private InsnList insns;
+
+ private List<TryCatchBlockNode>[] handlers;
+
+ private Frame<V>[] frames;
+
+ private Subroutine[] subroutines;
+
+ private boolean[] queued;
+
+ private int[] queue;
+
+ private int top;
+
+ public Data[] getData() {
+ return data;
+ }
+
+ private Data[] data;
+
+ public AnalyzerExt(final MyInterpreter interpreter, Data[] data, Data startData) {
+ this.interpreter = interpreter;
+ this.data = data;
+ if (data.length > 0) {
+ data[0] = startData;
+ }
+ }
+
+ public Frame<V>[] analyze(final String owner, final MethodNode m) throws AnalyzerException {
+ if ((m.access & (ACC_ABSTRACT | ACC_NATIVE)) != 0) {
+ frames = (Frame<V>[]) new Frame<?>[0];
+ return frames;
+ }
+ final V refV = (V) BasicValue.REFERENCE_VALUE;
+
+ n = m.instructions.size();
+ insns = m.instructions;
+ handlers = (List<TryCatchBlockNode>[]) new List<?>[n];
+ frames = (Frame<V>[]) new Frame<?>[n];
+ subroutines = new Subroutine[n];
+ queued = new boolean[n];
+ queue = new int[n];
+ top = 0;
+
+ // computes exception handlers for each instruction
+ for (int i = 0; i < m.tryCatchBlocks.size(); ++i) {
+ TryCatchBlockNode tcb = m.tryCatchBlocks.get(i);
+ int begin = insns.indexOf(tcb.start);
+ int end = insns.indexOf(tcb.end);
+ for (int j = begin; j < end; ++j) {
+ List<TryCatchBlockNode> insnHandlers = handlers[j];
+ if (insnHandlers == null) {
+ insnHandlers = new ArrayList<TryCatchBlockNode>();
+ handlers[j] = insnHandlers;
+ }
+ insnHandlers.add(tcb);
+ }
+ }
+
+ // computes the subroutine for each instruction:
+ Subroutine main = new Subroutine(null, m.maxLocals, null);
+ List<AbstractInsnNode> subroutineCalls = new ArrayList<AbstractInsnNode>();
+ Map<LabelNode, Subroutine> subroutineHeads = new HashMap<LabelNode, Subroutine>();
+ findSubroutine(0, main, subroutineCalls);
+ while (!subroutineCalls.isEmpty()) {
+ JumpInsnNode jsr = (JumpInsnNode) subroutineCalls.remove(0);
+ Subroutine sub = subroutineHeads.get(jsr.label);
+ if (sub == null) {
+ sub = new Subroutine(jsr.label, m.maxLocals, jsr);
+ subroutineHeads.put(jsr.label, sub);
+ findSubroutine(insns.indexOf(jsr.label), sub, subroutineCalls);
+ } else {
+ sub.callers.add(jsr);
+ }
+ }
+ for (int i = 0; i < n; ++i) {
+ if (subroutines[i] != null && subroutines[i].start == null) {
+ subroutines[i] = null;
+ }
+ }
+
+ // initializes the data structures for the control flow analysis
+ Frame<V> current = newFrame(m.maxLocals, m.maxStack);
+ Frame<V> handler = newFrame(m.maxLocals, m.maxStack);
+ current.setReturn(interpreter.newValue(Type.getReturnType(m.desc)));
+ Type[] args = Type.getArgumentTypes(m.desc);
+ int local = 0;
+ if ((m.access & ACC_STATIC) == 0) {
+ Type ctype = Type.getObjectType(owner);
+ current.setLocal(local++, interpreter.newValue(ctype));
+ }
+ for (int i = 0; i < args.length; ++i) {
+ current.setLocal(local++, interpreter.newValue(args[i]));
+ if (args[i].getSize() == 2) {
+ current.setLocal(local++, interpreter.newValue(null));
+ }
+ }
+ while (local < m.maxLocals) {
+ current.setLocal(local++, interpreter.newValue(null));
+ }
+
+ interpreter.init(data[0]);
+ merge(0, current, null);
+
+ init(owner, m);
+
+ // control flow analysis
+ while (top > 0) {
+ int insn = queue[--top];
+ Frame<V> f = frames[insn];
+ Subroutine subroutine = subroutines[insn];
+ queued[insn] = false;
+
+ AbstractInsnNode insnNode = null;
+ try {
+ insnNode = m.instructions.get(insn);
+ int insnOpcode = insnNode.getOpcode();
+ int insnType = insnNode.getType();
+
+ if (insnType == AbstractInsnNode.LABEL
+ || insnType == AbstractInsnNode.LINE
+ || insnType == AbstractInsnNode.FRAME) {
+ interpreter.init(data[insn]);
+ merge(insn + 1, f, subroutine);
+ newControlFlowEdge(insn, insn + 1);
+ } else {
+ // delta
+ interpreter.init(data[insn]);
+ current.init(f).execute(insnNode, interpreter);
+ subroutine = subroutine == null ? null : subroutine.copy();
+
+ if (insnNode instanceof JumpInsnNode) {
+ JumpInsnNode j = (JumpInsnNode) insnNode;
+ if (insnOpcode != GOTO && insnOpcode != JSR) {
+ merge(insn + 1, current, subroutine);
+ newControlFlowEdge(insn, insn + 1);
+ }
+ int jump = insns.indexOf(j.label);
+ if (insnOpcode == JSR) {
+ merge(jump, current, new Subroutine(j.label,
+ m.maxLocals, j));
+ } else {
+ merge(jump, current, subroutine);
+ }
+ newControlFlowEdge(insn, jump);
+ } else if (insnNode instanceof LookupSwitchInsnNode) {
+ LookupSwitchInsnNode lsi = (LookupSwitchInsnNode) insnNode;
+ int jump = insns.indexOf(lsi.dflt);
+ merge(jump, current, subroutine);
+ newControlFlowEdge(insn, jump);
+ for (int j = 0; j < lsi.labels.size(); ++j) {
+ LabelNode label = lsi.labels.get(j);
+ jump = insns.indexOf(label);
+ merge(jump, current, subroutine);
+ newControlFlowEdge(insn, jump);
+ }
+ } else if (insnNode instanceof TableSwitchInsnNode) {
+ TableSwitchInsnNode tsi = (TableSwitchInsnNode) insnNode;
+ int jump = insns.indexOf(tsi.dflt);
+ merge(jump, current, subroutine);
+ newControlFlowEdge(insn, jump);
+ for (int j = 0; j < tsi.labels.size(); ++j) {
+ LabelNode label = tsi.labels.get(j);
+ jump = insns.indexOf(label);
+ merge(jump, current, subroutine);
+ newControlFlowEdge(insn, jump);
+ }
+ } else if (insnOpcode == RET) {
+ if (subroutine == null) {
+ throw new AnalyzerException(insnNode,
+ "RET instruction outside of a sub routine");
+ }
+ for (int i = 0; i < subroutine.callers.size(); ++i) {
+ JumpInsnNode caller = subroutine.callers.get(i);
+ int call = insns.indexOf(caller);
+ if (frames[call] != null) {
+ merge(call + 1, frames[call], current,
+ subroutines[call], subroutine.access);
+ newControlFlowEdge(insn, call + 1);
+ }
+ }
+ } else if (insnOpcode != ATHROW && (insnOpcode < IRETURN || insnOpcode > RETURN)) {
+ if (subroutine != null) {
+ if (insnNode instanceof VarInsnNode) {
+ int var = ((VarInsnNode) insnNode).var;
+ subroutine.access[var] = true;
+ if (insnOpcode == LLOAD || insnOpcode == DLOAD
+ || insnOpcode == LSTORE
+ || insnOpcode == DSTORE) {
+ subroutine.access[var + 1] = true;
+ }
+ } else if (insnNode instanceof IincInsnNode) {
+ int var = ((IincInsnNode) insnNode).var;
+ subroutine.access[var] = true;
+ }
+ }
+ merge(insn + 1, current, subroutine);
+ newControlFlowEdge(insn, insn + 1);
+ }
+ }
+
+ List<TryCatchBlockNode> insnHandlers = handlers[insn];
+ if (insnHandlers != null) {
+ for (int i = 0; i < insnHandlers.size(); ++i) {
+ TryCatchBlockNode tcb = insnHandlers.get(i);
+ int jump = insns.indexOf(tcb.handler);
+ if (newControlFlowExceptionEdge(insn, tcb)) {
+ handler.init(f);
+ handler.clearStack();
+ handler.push(refV);
+ merge(jump, handler, subroutine);
+ }
+ }
+ }
+ } catch (AnalyzerException e) {
+ throw new AnalyzerException(e.node, "Error at instruction "
+ + insn + ": " + e.getMessage(), e);
+ } catch (Exception e) {
+ throw new AnalyzerException(insnNode, "Error at instruction "
+ + insn + ": " + e.getMessage(), e);
+ }
+ }
+
+ return frames;
+ }
+
+ private void findSubroutine(int insn, final Subroutine sub,
+ final List<AbstractInsnNode> calls) throws AnalyzerException {
+ while (true) {
+ if (insn < 0 || insn >= n) {
+ throw new AnalyzerException(null,
+ "Execution can fall off end of the code");
+ }
+ if (subroutines[insn] != null) {
+ return;
+ }
+ subroutines[insn] = sub.copy();
+ AbstractInsnNode node = insns.get(insn);
+
+ // calls findSubroutine recursively on normal successors
+ if (node instanceof JumpInsnNode) {
+ if (node.getOpcode() == JSR) {
+ // do not follow a JSR, it leads to another subroutine!
+ calls.add(node);
+ } else {
+ JumpInsnNode jnode = (JumpInsnNode) node;
+ findSubroutine(insns.indexOf(jnode.label), sub, calls);
+ }
+ } else if (node instanceof TableSwitchInsnNode) {
+ TableSwitchInsnNode tsnode = (TableSwitchInsnNode) node;
+ findSubroutine(insns.indexOf(tsnode.dflt), sub, calls);
+ for (int i = tsnode.labels.size() - 1; i >= 0; --i) {
+ LabelNode l = tsnode.labels.get(i);
+ findSubroutine(insns.indexOf(l), sub, calls);
+ }
+ } else if (node instanceof LookupSwitchInsnNode) {
+ LookupSwitchInsnNode lsnode = (LookupSwitchInsnNode) node;
+ findSubroutine(insns.indexOf(lsnode.dflt), sub, calls);
+ for (int i = lsnode.labels.size() - 1; i >= 0; --i) {
+ LabelNode l = lsnode.labels.get(i);
+ findSubroutine(insns.indexOf(l), sub, calls);
+ }
+ }
+
+ // calls findSubroutine recursively on exception handler successors
+ List<TryCatchBlockNode> insnHandlers = handlers[insn];
+ if (insnHandlers != null) {
+ for (int i = 0; i < insnHandlers.size(); ++i) {
+ TryCatchBlockNode tcb = insnHandlers.get(i);
+ findSubroutine(insns.indexOf(tcb.handler), sub, calls);
+ }
+ }
+
+ // if insn does not falls through to the next instruction, return.
+ switch (node.getOpcode()) {
+ case GOTO:
+ case RET:
+ case TABLESWITCH:
+ case LOOKUPSWITCH:
+ case IRETURN:
+ case LRETURN:
+ case FRETURN:
+ case DRETURN:
+ case ARETURN:
+ case RETURN:
+ case ATHROW:
+ return;
+ }
+ insn++;
+ }
+ }
+
+ public Frame<V>[] getFrames() {
+ return frames;
+ }
+
+ public List<TryCatchBlockNode> getHandlers(final int insn) {
+ return handlers[insn];
+ }
+
+ protected void init(String owner, MethodNode m) throws AnalyzerException {
+ }
+
+ protected Frame<V> newFrame(final int nLocals, final int nStack) {
+ return new Frame<V>(nLocals, nStack);
+ }
+
+ protected Frame<V> newFrame(final Frame<? extends V> src) {
+ return new Frame<V>(src);
+ }
+
+ protected void newControlFlowEdge(final int insn, final int successor) {
+ }
+
+ protected boolean newControlFlowExceptionEdge(final int insn,
+ final int successor) {
+ return true;
+ }
+
+ protected boolean newControlFlowExceptionEdge(final int insn,
+ final TryCatchBlockNode tcb) {
+ return newControlFlowExceptionEdge(insn, insns.indexOf(tcb.handler));
+ }
+
+ // -------------------------------------------------------------------------
+
+ private void merge(final int insn, final Frame<V> frame,
+ final Subroutine subroutine) throws AnalyzerException {
+ Frame<V> oldFrame = frames[insn];
+ Subroutine oldSubroutine = subroutines[insn];
+ boolean changes;
+
+ if (oldFrame == null) {
+ frames[insn] = newFrame(frame);
+ changes = true;
+ } else {
+ changes = oldFrame.merge(frame, interpreter);
+ }
+
+ if (oldSubroutine == null) {
+ if (subroutine != null) {
+ subroutines[insn] = subroutine.copy();
+ changes = true;
+ }
+ } else {
+ if (subroutine != null) {
+ changes |= oldSubroutine.merge(subroutine);
+ }
+ }
+ if (changes && !queued[insn]) {
+ queued[insn] = true;
+ queue[top++] = insn;
+ }
+
+ // delta
+ mergeData(insn, interpreter);
+ }
+
+ private void merge(final int insn, final Frame<V> beforeJSR,
+ final Frame<V> afterRET, final Subroutine subroutineBeforeJSR,
+ final boolean[] access) throws AnalyzerException {
+ Frame<V> oldFrame = frames[insn];
+ Subroutine oldSubroutine = subroutines[insn];
+ boolean changes;
+
+ afterRET.merge(beforeJSR, access);
+
+ if (oldFrame == null) {
+ frames[insn] = newFrame(afterRET);
+ changes = true;
+ } else {
+ changes = oldFrame.merge(afterRET, interpreter);
+ }
+
+ if (oldSubroutine != null && subroutineBeforeJSR != null) {
+ changes |= oldSubroutine.merge(subroutineBeforeJSR);
+ }
+ if (changes && !queued[insn]) {
+ queued[insn] = true;
+ queue[top++] = insn;
+ }
+
+ // delta
+ mergeData(insn, interpreter);
+ }
+
+ private void mergeData(int insn, MyInterpreter interpreter) {
+ boolean changes = false;
+
+ Data oldData = data[insn];
+ Data newData = interpreter.getAfterData(insn);
+
+ if (oldData == null) {
+ data[insn] = newData;
+ changes = true;
+ } else if (newData != null) {
+ Data mergedData = interpreter.merge(oldData, newData);
+ data[insn] = mergedData;
+ changes = !oldData.equals(mergedData);
+ }
+
+ if (changes && !queued[insn]) {
+ queued[insn] = true;
+ queue[top++] = insn;
+ }
+ }
+}