fix bug reported by Benedikt Nordhoff on mailing list: for cases where an enclosing exception handler catches all exception types, don't add an exceptional edge from a throw instruction to method exit.

git-svn-id: https://wala.svn.sourceforge.net/svnroot/wala/trunk@4057 f5eafffb-2e1d-0410-98e4-8ec43c5233c4

com.ibm.wala.core.testdata/src/cfg/MonitorTest.java

@@ -0,0 +1,24 @@
+package cfg;
+
+public class MonitorTest {
+  void sync1() {
+    Object a = new Object();
+    synchronized (this) {
+      synchronized (a) {
+        dummy();
+      }
+    }
+  }
+
+  void sync2() {
+    Object a = new Object();
+    synchronized (this) {
+      synchronized (a) {
+        // Nothing here.
+      }
+    }
+  }
+
+  void dummy() {
+  }
+}

com.ibm.wala.core.tests/src/com/ibm/wala/core/tests/ir/CFGTest.java

@@ -10,21 +10,27 @@
  *******************************************************************************/
 package com.ibm.wala.core.tests.ir;
 
+import org.junit.AfterClass;
 import org.junit.Assert;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 import com.ibm.wala.cfg.ControlFlowGraph;
+import com.ibm.wala.classLoader.ClassLoaderFactory;
+import com.ibm.wala.classLoader.ClassLoaderFactoryImpl;
 import com.ibm.wala.classLoader.IMethod;
 import com.ibm.wala.classLoader.Language;
-import com.ibm.wala.core.tests.callGraph.CallGraphTestUtil;
+import com.ibm.wala.core.tests.util.TestConstants;
 import com.ibm.wala.core.tests.util.WalaTestCase;
 import com.ibm.wala.ipa.callgraph.AnalysisCache;
 import com.ibm.wala.ipa.callgraph.AnalysisOptions;
 import com.ibm.wala.ipa.callgraph.AnalysisScope;
 import com.ibm.wala.ipa.callgraph.impl.Everywhere;
 import com.ibm.wala.ipa.cha.ClassHierarchy;
+import com.ibm.wala.ipa.cha.ClassHierarchyException;
 import com.ibm.wala.ssa.IR;
 import com.ibm.wala.ssa.ISSABasicBlock;
+import com.ibm.wala.ssa.SSACFG;
 import com.ibm.wala.ssa.SSAInstruction;
 import com.ibm.wala.ssa.SSAOptions;
 import com.ibm.wala.types.MethodReference;
@@ -34,12 +40,38 @@ import com.ibm.wala.util.graph.GraphIntegrity;
 import com.ibm.wala.util.graph.GraphIntegrity.UnsoundGraphException;
 import com.ibm.wala.util.io.FileProvider;
 import com.ibm.wala.util.strings.StringStuff;
+import com.ibm.wala.util.warnings.Warnings;
 
 /**
  * Test integrity of CFGs
  */
 public class CFGTest extends WalaTestCase {
 
+  private static AnalysisScope scope;
+
+  private static ClassHierarchy cha;
+
+  @BeforeClass
+  public static void beforeClass() throws Exception {
+
+    scope = AnalysisScopeReader.readJavaScope(TestConstants.WALA_TESTDATA,
+        FileProvider.getFile("J2SEClassHierarchyExclusions.txt"), CFGTest.class.getClassLoader());
+    ClassLoaderFactory factory = new ClassLoaderFactoryImpl(scope.getExclusions());
+
+    try {
+      cha = ClassHierarchy.make(scope, factory);
+    } catch (ClassHierarchyException e) {
+      throw new Exception();
+    }
+  }
+
+  @AfterClass
+  public static void afterClass() throws Exception {
+    Warnings.clear();
+    scope = null;
+    cha = null;
+  }
+
   public static void main(String[] args) {
     justThisTest(CFGTest.class);
   }
@@ -49,10 +81,6 @@ public class CFGTest extends WalaTestCase {
    */
   private void doMethod(String methodSig) {
     try {
-      AnalysisScope scope = AnalysisScopeReader.makePrimordialScope(FileProvider.getFile(CallGraphTestUtil.REGRESSION_EXCLUSIONS));
-
-      ClassHierarchy cha = ClassHierarchy.make(scope);
-
       MethodReference mr = StringStuff.makeMethodReference(Language.JAVA, methodSig);
 
       IMethod m = cha.resolveMethod(mr);
@@ -88,11 +116,38 @@ public class CFGTest extends WalaTestCase {
   }
 
   /**
-   * this method does not exist in 1.5 libraries @Test public void testFDBigInt() {
-   * doMethod("java.lang.FDBigInt.class$(Ljava/lang/String;)Ljava/lang/Class;"); }
+   * this method does not exist in 1.5 libraries @Test public void
+   * testFDBigInt() {
+   * doMethod("java.lang.FDBigInt.class$(Ljava/lang/String;)Ljava/lang/Class;");
+   * }
    */
 
-  @Test public void testResolveProxyClass() {
+  @Test
+  public void testResolveProxyClass() {
     doMethod("java.io.ObjectInputStream.resolveProxyClass([Ljava/lang/String;)Ljava/lang/Class;");
   }
+
+  @Test
+  public void testSync1() {
+    MethodReference mr = StringStuff.makeMethodReference("cfg.MonitorTest.sync1()V");
+
+    IMethod m = cha.resolveMethod(mr);
+    AnalysisCache cache = new AnalysisCache();
+    IR ir = cache.getIR(m);
+    SSACFG controlFlowGraph = ir.getControlFlowGraph();
+//    System.out.println(ir);
+    Assert.assertEquals(1, controlFlowGraph.getSuccNodeCount(controlFlowGraph.getBlockForInstruction(21)));
+  }
+
+  /**
+  @Test
+  public void testSync2() {
+    MethodReference mr = StringStuff.makeMethodReference("cfg.MonitorTest.sync2()V");
+
+    IMethod m = cha.resolveMethod(mr);
+    AnalysisCache cache = new AnalysisCache();
+    IR ir = cache.getIR(m);
+    System.out.println(ir);
+  }
+  */
 }

com.ibm.wala.core/src/com/ibm/wala/cfg/ShrikeCFG.java

@@ -303,6 +303,9 @@ public class ShrikeCFG extends AbstractCFG<IInstruction, ShrikeCFG.BasicBlock> {
             exceptionTypes = HashSetFactory.make(exceptionTypes);
           }
 
+          // this var gets set to false if goToAllHandlers is true but some enclosing exception handler catches all
+          // exceptions.  in such a case, we need not add an exceptional edge to the method exit
+          boolean needEdgeToExitForAllHandlers = true;
           for (int j = 0; j < hs.length; j++) {
             if (DEBUG) {
               System.err.println(" handler " + hs[j]);
@@ -317,6 +320,10 @@ public class ShrikeCFG extends AbstractCFG<IInstruction, ShrikeCFG.BasicBlock> {
                 System.err.println(" gotoAllHandlers " + b);
               }
               addExceptionalEdgeTo(b);
+              // if the handler catches all exceptions, we don't need to add an edge to the exit
+              if (hs[j].getCatchClass() == null) {
+                needEdgeToExitForAllHandlers = false;
+              }
             } else {
               TypeReference caughtException = null;
               if (hs[j].getCatchClass() != null) {
@@ -376,7 +383,7 @@ public class ShrikeCFG extends AbstractCFG<IInstruction, ShrikeCFG.BasicBlock> {
             }
           }
           // if needed, add an edge to the exit block.
-          if (exceptionTypes == null || !exceptionTypes.isEmpty()) {
+          if ((exceptionTypes == null && needEdgeToExitForAllHandlers) || (exceptionTypes != null && !exceptionTypes.isEmpty())) {
             BasicBlock exit = exit();
             addExceptionalEdgeTo(exit);
           }