1 files changed, 174 insertions, 0 deletions
diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/ControlFlowGraph.java b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/ControlFlowGraph.java
new file mode 100644
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--- /dev/null
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/ControlFlowGraph.java
@@ -0,0 +1,174 @@
+/*
+ * 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 com.intellij.codeInspection.bytecodeAnalysis.asm.ControlFlowGraph.Edge;
+import gnu.trove.TIntArrayList;
+import org.jetbrains.org.objectweb.asm.tree.MethodNode;
+import org.jetbrains.org.objectweb.asm.tree.analysis.AnalyzerException;
+
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * @author lambdamix
+ */
+public final class ControlFlowGraph {
+  public static final class Edge {
+    public final int from, to;
+
+    public Edge(int from, int to) {
+      this.from = from;
+      this.to = to;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) return true;
+      if (!(o instanceof Edge)) {
+        return false;
+      }
+      Edge edge = (Edge) o;
+      return from == edge.from && to == edge.to;
+    }
+
+    @Override
+    public int hashCode() {
+      return 31 * from + to;
+    }
+  }
+
+  public final String className;
+  public final MethodNode methodNode;
+  public final int[][] transitions;
+  public final int edgeCount;
+  public final boolean[] errors;
+  public final Set<Edge> errorTransitions;
+
+  ControlFlowGraph(String className, MethodNode methodNode, int[][] transitions, int edgeCount, boolean[] errors, Set<Edge> errorTransitions) {
+    this.className = className;
+    this.methodNode = methodNode;
+    this.transitions = transitions;
+    this.edgeCount = edgeCount;
+    this.errors = errors;
+    this.errorTransitions = errorTransitions;
+  }
+
+  public static ControlFlowGraph build(String className, MethodNode methodNode, boolean jsr) throws AnalyzerException {
+    return jsr ? new ControlFlowBuilder(className, methodNode).buildCFG() : new LiteControlFlowBuilder(className, methodNode).buildCFG();
+  }
+}
+
+final class ControlFlowBuilder extends FramelessAnalyzer {
+  final String className;
+  final MethodNode methodNode;
+  final TIntArrayList[] transitions;
+  final Set<ControlFlowGraph.Edge> errorTransitions;
+  private final boolean[] errors;
+  private int edgeCount;
+
+  ControlFlowBuilder(String className, MethodNode methodNode) {
+    this.className = className;
+    this.methodNode = methodNode;
+    transitions = new TIntArrayList[methodNode.instructions.size()];
+    errors = new boolean[methodNode.instructions.size()];
+    for (int i = 0; i < transitions.length; i++) {
+      transitions[i] = new TIntArrayList();
+    }
+    errorTransitions = new HashSet<Edge>();
+  }
+
+  final ControlFlowGraph buildCFG() throws AnalyzerException {
+    if ((methodNode.access & (ACC_ABSTRACT | ACC_NATIVE)) == 0) {
+      analyze(methodNode);
+    }
+    int[][] resultTransitions = new int[transitions.length][];
+    for (int i = 0; i < resultTransitions.length; i++) {
+      resultTransitions[i] = transitions[i].toNativeArray();
+    }
+    return new ControlFlowGraph(className, methodNode, resultTransitions, edgeCount, errors, errorTransitions);
+  }
+
+  @Override
+  protected final void newControlFlowEdge(int insn, int successor) {
+    if (!transitions[insn].contains(successor)) {
+      transitions[insn].add(successor);
+      edgeCount++;
+    }
+  }
+
+  @Override
+  protected final boolean newControlFlowExceptionEdge(int insn, int successor) {
+    if (!transitions[insn].contains(successor)) {
+      transitions[insn].add(successor);
+      edgeCount++;
+      errorTransitions.add(new Edge(insn, successor));
+      errors[successor] = true;
+    }
+    return true;
+  }
+}
+
+final class LiteControlFlowBuilder extends LiteFramelessAnalyzer {
+  final String className;
+  final MethodNode methodNode;
+  final TIntArrayList[] transitions;
+  final Set<ControlFlowGraph.Edge> errorTransitions;
+  private final boolean[] errors;
+  private int edgeCount;
+
+  LiteControlFlowBuilder(String className, MethodNode methodNode) {
+    this.className = className;
+    this.methodNode = methodNode;
+    transitions = new TIntArrayList[methodNode.instructions.size()];
+    errors = new boolean[methodNode.instructions.size()];
+    for (int i = 0; i < transitions.length; i++) {
+      transitions[i] = new TIntArrayList();
+    }
+    errorTransitions = new HashSet<Edge>();
+  }
+
+  final ControlFlowGraph buildCFG() throws AnalyzerException {
+    if ((methodNode.access & (ACC_ABSTRACT | ACC_NATIVE)) == 0) {
+      analyze(methodNode);
+    }
+    int[][] resultTransitions = new int[transitions.length][];
+    for (int i = 0; i < resultTransitions.length; i++) {
+      resultTransitions[i] = transitions[i].toNativeArray();
+    }
+    return new ControlFlowGraph(className, methodNode, resultTransitions, edgeCount, errors, errorTransitions);
+  }
+
+  @Override
+  protected final void newControlFlowEdge(int insn, int successor) {
+    if (!transitions[insn].contains(successor)) {
+      transitions[insn].add(successor);
+      edgeCount++;
+    }
+  }
+
+  @Override
+  protected final boolean newControlFlowExceptionEdge(int insn, int successor) {
+    if (!transitions[insn].contains(successor)) {
+      transitions[insn].add(successor);
+      edgeCount++;
+      errorTransitions.add(new Edge(insn, successor));
+      errors[successor] = true;
+    }
+    return true;
+  }
+}
+