1 files changed, 74 insertions, 0 deletions
diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/Subroutine.java b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/Subroutine.java
new file mode 100644
index 000000000000..a484b1b1fdb1
--- /dev/null
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/bytecodeAnalysis/asm/Subroutine.java
@@ -0,0 +1,74 @@
+/*
+ * 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.annotations.Nullable;
+import org.jetbrains.org.objectweb.asm.tree.JumpInsnNode;
+import org.jetbrains.org.objectweb.asm.tree.LabelNode;
+import org.jetbrains.org.objectweb.asm.tree.analysis.AnalyzerException;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @author lambdamix
+ */
+public class Subroutine {
+
+  LabelNode start;
+  boolean[] access;
+  List<JumpInsnNode> callers;
+
+  private Subroutine() {
+  }
+
+  Subroutine(@Nullable final LabelNode start, final int maxLocals,
+             @Nullable final JumpInsnNode caller) {
+    this.start = start;
+    this.access = new boolean[maxLocals];
+    this.callers = new ArrayList<JumpInsnNode>();
+    callers.add(caller);
+  }
+
+  public Subroutine copy() {
+    Subroutine result = new Subroutine();
+    result.start = start;
+    result.access = new boolean[access.length];
+    System.arraycopy(access, 0, result.access, 0, access.length);
+    result.callers = new ArrayList<JumpInsnNode>(callers);
+    return result;
+  }
+
+  public boolean merge(final Subroutine subroutine) throws AnalyzerException {
+    boolean changes = false;
+    for (int i = 0; i < access.length; ++i) {
+      if (subroutine.access[i] && !access[i]) {
+        access[i] = true;
+        changes = true;
+      }
+    }
+    if (subroutine.start == start) {
+      for (int i = 0; i < subroutine.callers.size(); ++i) {
+        JumpInsnNode caller = subroutine.callers.get(i);
+        if (!callers.contains(caller)) {
+          callers.add(caller);
+          changes = true;
+        }
+      }
+    }
+    return changes;
+  }
+}