Improves termination logic

Termination instruction no longer throws exceptions

Conflicts:
	svm-jinstruction/src/main/java/com/lexicalscope/svm/j/instruction/StateAssertion.java
	svm-jinstruction/src/main/java/com/lexicalscope/svm/j/instruction/concrete/exceptions/AThrowOp.java
	svm-partition-trace-symb/src/main/java/com/lexicalscope/svm/search2/TreeSearch.java
	svm-vm/src/main/java/com/lexicalscope/svm/vm/VmImpl.java

Author: drognanar

svm-jcore/src/main/java/com/lexicalscope/svm/vm/j/JState.java

@@ -20,7 +20,7 @@ public interface JState extends Snapshotable<JState>, VmState {
    StackFrame previousFrame();
    StackFrame currentFrame();
 
-   void complete();
+   void terminate();
 
    void advanceToNextInstruction();
    void advanceTo(Instruction instruction);

svm-jcore/src/main/java/com/lexicalscope/svm/vm/j/JStateAdaptor.java

@@ -54,7 +54,8 @@ public StackFrame currentFrame() {
    }
 
    @Override
-   public void complete() {
+   public void terminate() {
+      delegate.terminate();
    }
 
    @Override

svm-jcore/src/main/java/com/lexicalscope/svm/vm/j/JStateImpl.java

@@ -276,7 +276,8 @@ public StackFrame previousFrame() {
    }
 
    @Override
-   public void complete() {
+   public void terminate() {
+      search.reachedLeaf();
       heap = null;
       statics = null;
    }

svm-jinstruction/src/main/java/com/lexicalscope/svm/j/instruction/TerminateInstruction.java

@@ -22,7 +22,7 @@ public class TerminateInstruction implements Instruction {
    @Override public void eval(final JState ctx) {
       // TODO[tim]: demeter
       ctx.setMeta(TerminationMetaKey.TERMINATION, true);
-      throw new TerminationException();
+      ctx.terminate();
    }
 
    @Override public Collection<Instruction> targetOf() {

svm-jinstruction/src/main/java/com/lexicalscope/svm/j/instruction/concrete/method/MethodCallInstruction.java

@@ -4,6 +4,7 @@
 
 import com.lexicalscope.svm.heap.ObjectRef;
 import com.lexicalscope.svm.j.instruction.MethodCallVop;
+import com.lexicalscope.svm.j.instruction.StateAssertion;
 import com.lexicalscope.svm.j.instruction.concrete.klass.LoadingOp;
 import com.lexicalscope.svm.j.instruction.factory.InstructionSource;
 import com.lexicalscope.svm.stack.MethodScope;
@@ -108,6 +109,7 @@ private int argSize(final SMethodDescriptor targetMethod) {
    }
 
    private static Resolution resolveVirtualMethod(final Object[] args, final SMethodDescriptor sMethodName, final JState ctx) {
+      StateAssertion.assertState(ctx, args[0] != ctx.nullPointer(), "Cannot be null");
       final MethodResolver receiverKlass = receiver(args, sMethodName, ctx);
       return new Resolution(receiverKlass.virtualMethod(sMethodName));
    }

svm-partition-trace-symb/src/main/java/com/lexicalscope/svm/search2/TreeSearch.java

@@ -90,7 +90,6 @@ public void selectAnotherTree(final List<TraceTree> withStatesAvailable) {
    }
 
    @Override public void reachedLeaf() {
-      pendingJState.complete();
       observer.leaf(pendingJState);
       results.add(pendingJState);
 

svm-partition-trace-symb/src/test/java/com/lexicalscope/svm/partition/trace/symb/search/FakeVmState.java

@@ -63,7 +63,7 @@ public FakeVmState(final String string) {
    }
 
    @Override
-   public void complete() {
+   public void terminate() {
 
    }
 

svm-vm/src/main/java/com/lexicalscope/svm/vm/TerminationException.java

@@ -1,4 +1,9 @@
 package com.lexicalscope.svm.vm;
 
 
-public class TerminationException extends RuntimeException {}
+public class TerminationException extends RuntimeException {
+    @Override
+    public synchronized Throwable fillInStackTrace() {
+        return null;
+    }
+}

svm-vm/src/test/java/com/lexicalscope/svm/vm/TestVmImpl.java

@@ -1,7 +1,10 @@
 package com.lexicalscope.svm.vm;
 
+import org.hamcrest.Description;
 import org.jmock.Expectations;
 import org.jmock.Sequence;
+import org.jmock.api.Action;
+import org.jmock.api.Invocation;
 import org.jmock.auto.Auto;
 import org.jmock.auto.Mock;
 import org.jmock.integration.junit4.JUnitRuleMockery;
@@ -19,6 +22,19 @@ public class TestVmImpl {
    @Mock protected VmState state0;
    @Mock protected VmState stateR;
 
+   private final Action callTermination = new Action() {
+      @Override
+      public Object invoke(Invocation invocation) throws Throwable {
+         search.reachedLeaf();
+         return null;
+      }
+
+      @Override
+      public void describeTo(Description description) {
+
+      }
+   };
+
    @Test public void pendingStatesAreEvaluatedWhileAvailable() {
       context.checking(new Expectations(){{
          oneOf(limits).reset(); inSequence(limitsOrder);
@@ -38,7 +54,7 @@ public class TestVmImpl {
          oneOf(limits).reset(); inSequence(limitsOrder);
          oneOf(search).pendingState(); will(returnValue(state0));
          oneOf(limits).withinLimits(); will(returnValue(true)); inSequence(limitsOrder);
-         oneOf(state0).eval(); will(throwException(new TerminationException()));
+         oneOf(state0).eval(); will(callTermination);
          oneOf(search).reachedLeaf();
          oneOf(limits).searchedState(); inSequence(limitsOrder);
          oneOf(search).pendingState(); will(returnValue(null));