diff --git a/src/compiler/codegen/CodegenUtil.cc b/src/compiler/codegen/CodegenUtil.cc
index 3aea76a..bdc2c8b 100644
--- a/src/compiler/codegen/CodegenUtil.cc
+++ b/src/compiler/codegen/CodegenUtil.cc
@@ -998,5 +998,20 @@
   }
 }
 
+/*
+ * Set up special LIR to mark a Dalvik byte-code instruction start and
+ * record it in the boundaryMap.  NOTE: in cases such as kMirOpCheck in
+ * which we split a single Dalvik instruction, only the first MIR op
+ * associated with a Dalvik PC should be entered into the map.
+ */
+LIR* markBoundary(CompilationUnit* cUnit, int offset, const char* instStr)
+{
+  LIR* res = newLIR1(cUnit, kPseudoDalvikByteCodeBoundary, (intptr_t) instStr);
+  if (cUnit->boundaryMap.find(offset) == cUnit->boundaryMap.end()) {
+    cUnit->boundaryMap.Put(offset, res);
+  }
+  return res;
+}
 
-}  // namespace art
+}
+ // namespace art
diff --git a/src/compiler/codegen/MethodBitcode.cc b/src/compiler/codegen/MethodBitcode.cc
index cfe6e6a..8d62750 100644
--- a/src/compiler/codegen/MethodBitcode.cc
+++ b/src/compiler/codegen/MethodBitcode.cc
@@ -1668,8 +1668,11 @@
         DCHECK_EQ(rlDest.fp, loc.fp);
         DCHECK_EQ(rlDest.core, loc.core);
         DCHECK_EQ(rlDest.ref, loc.ref);
+        SafeMap<unsigned int, unsigned int>::iterator it;
+        it = cUnit->blockIdMap.find(incoming[i]);
+        DCHECK(it != cUnit->blockIdMap.end());
         phi->addIncoming(getLLVMValue(cUnit, loc.origSReg),
-                         getLLVMBlock(cUnit, incoming[i]));
+                         getLLVMBlock(cUnit, it->second));
       }
       defineValue(cUnit, phi, rlDest.origSReg);
       break;
@@ -1752,6 +1755,7 @@
 /* Handle the content in each basic block */
 bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
 {
+  if (bb->blockType == kDead) return false;
   llvm::BasicBlock* llvmBB = getLLVMBlock(cUnit, bb->id);
   cUnit->irb->SetInsertPoint(llvmBB);
   setDexOffset(cUnit, bb->startOffset);
@@ -1964,7 +1968,7 @@
 bool createLLVMBasicBlock(CompilationUnit* cUnit, BasicBlock* bb)
 {
   // Skip the exit block
-  if (bb->blockType == kExitBlock) {
+  if ((bb->blockType == kDead) ||(bb->blockType == kExitBlock)) {
     cUnit->idToBlockMap.Put(bb->id, NULL);
   } else {
     int offset = bb->startOffset;
@@ -2924,11 +2928,8 @@
     cUnit->liveSReg = INVALID_SREG;
 #endif
 
-    LIR* boundaryLIR;
-    const char* instStr = "boundary";
-    boundaryLIR = newLIR1(cUnit, kPseudoDalvikByteCodeBoundary,
-                          (intptr_t) instStr);
-    cUnit->boundaryMap.Overwrite(cUnit->currentDalvikOffset, boundaryLIR);
+    // TODO: use llvm opcode name here instead of "boundary" if verbose
+    LIR* boundaryLIR = markBoundary(cUnit, cUnit->currentDalvikOffset, "boundary");
 
     /* Remember the first LIR for thisl block*/
     if (headLIR == NULL) {
diff --git a/src/compiler/codegen/MethodCodegenDriver.cc b/src/compiler/codegen/MethodCodegenDriver.cc
index b4e14ce..e76834d 100644
--- a/src/compiler/codegen/MethodCodegenDriver.cc
+++ b/src/compiler/codegen/MethodCodegenDriver.cc
@@ -881,14 +881,7 @@
   oatResetRegPool(cUnit);
   oatResetDefTracking(cUnit);
 
-  /*
-   * If control reached us from our immediate predecessor via
-   * fallthrough and we have no other incoming arcs we can
-   * reuse existing liveness.  Otherwise, reset.
-   */
-  if (!bb->fallThroughTarget || bb->predecessors->numUsed != 1) {
-    oatClobberAllRegs(cUnit);
-  }
+  oatClobberAllRegs(cUnit);
 
   LIR* headLIR = NULL;
 
@@ -922,9 +915,7 @@
     /* Mark the beginning of a Dalvik instruction for line tracking */
     char* instStr = cUnit->printMe ?
        oatGetDalvikDisassembly(cUnit, mir->dalvikInsn, "") : NULL;
-    boundaryLIR = newLIR1(cUnit, kPseudoDalvikByteCodeBoundary,
-                          (intptr_t) instStr);
-    cUnit->boundaryMap.Overwrite(mir->offset, boundaryLIR);
+    boundaryLIR = markBoundary(cUnit, mir->offset, instStr);
     /* Remember the first LIR for this block */
     if (headLIR == NULL) {
       headLIR = boundaryLIR;
diff --git a/src/compiler/codegen/arm/Thumb2/Gen.cc b/src/compiler/codegen/arm/Thumb2/Gen.cc
index d2532b7..925bbf2 100644
--- a/src/compiler/codegen/arm/Thumb2/Gen.cc
+++ b/src/compiler/codegen/arm/Thumb2/Gen.cc
@@ -127,13 +127,10 @@
 /* Used for the "printMe" listing */
 void genPrintLabel(CompilationUnit *cUnit, MIR* mir)
 {
-  LIR* boundaryLIR;
   /* Mark the beginning of a Dalvik instruction for line tracking */
   char* instStr = cUnit->printMe ?
      oatGetDalvikDisassembly(cUnit, mir->dalvikInsn, "") : NULL;
-  boundaryLIR = newLIR1(cUnit, kPseudoDalvikByteCodeBoundary,
-     (intptr_t) instStr);
-  cUnit->boundaryMap.Put(mir->offset, boundaryLIR);
+  markBoundary(cUnit, mir->offset, instStr);
   /* Don't generate the SSA annotation unless verbose mode is on */
   if (cUnit->printMe && mir->ssaRep) {
     char* ssaString = oatGetSSAString(cUnit, mir->ssaRep);