diff --git a/compiler/optimizing/builder.cc b/compiler/optimizing/builder.cc
index 8bf744d..8551382 100644
--- a/compiler/optimizing/builder.cc
+++ b/compiler/optimizing/builder.cc
@@ -259,24 +259,14 @@
   return false;
 }
 
-static const DexFile::TryItem* GetTryItem(HBasicBlock* block,
-                                          const DexFile::CodeItem& code_item,
-                                          const ArenaBitVector& can_block_throw) {
-  DCHECK(!block->IsSingleTryBoundary());
-
-  // Block does not contain throwing instructions. Even if it is covered by
-  // a TryItem, we will consider it not in a try block.
-  if (!can_block_throw.IsBitSet(block->GetBlockId())) {
-    return nullptr;
-  }
-
-  // Instructions in the block may throw. Find a TryItem covering this block.
-  int32_t try_item_idx = DexFile::FindTryItem(code_item, block->GetDexPc());
-  if (try_item_idx == -1) {
-    return nullptr;
-  } else {
-    return DexFile::GetTryItems(code_item, try_item_idx);
-  }
+bool HGraphBuilder::IsBlockInPcRange(HBasicBlock* block,
+                                     uint32_t dex_pc_start,
+                                     uint32_t dex_pc_end) {
+  uint32_t dex_pc = block->GetDexPc();
+  return block != entry_block_
+      && block != exit_block_
+      && dex_pc >= dex_pc_start
+      && dex_pc < dex_pc_end;
 }
 
 void HGraphBuilder::CreateBlocksForTryCatch(const DexFile::CodeItem& code_item) {
@@ -337,41 +327,30 @@
     return;
   }
 
-  const size_t num_blocks = graph_->GetBlocks().Size();
-  ArenaBitVector can_block_throw(arena_, num_blocks, false);
-
-  // Scan blocks and mark those which contain throwing instructions.
-  for (size_t block_id = 0; block_id < num_blocks; ++block_id) {
-    HBasicBlock* block = graph_->GetBlocks().Get(block_id);
-    for (HInstructionIterator insn(block->GetInstructions()); !insn.Done(); insn.Advance()) {
-      if (insn.Current()->CanThrow()) {
-        can_block_throw.SetBit(block_id);
-        break;
-      }
-    }
-  }
-
   // Iterate over all blocks, find those covered by some TryItem and:
   //   (a) split edges which enter/exit the try range,
   //   (b) create TryBoundary instructions in the new blocks,
   //   (c) link the new blocks to corresponding exception handlers.
   // We cannot iterate only over blocks in `branch_targets_` because switch-case
   // blocks share the same dex_pc.
-  for (size_t block_id = 1; block_id < num_blocks - 1; ++block_id) {
+  for (size_t block_id = 1, e = graph_->GetBlocks().Size(); block_id < e; ++block_id) {
     HBasicBlock* try_block = graph_->GetBlocks().Get(block_id);
 
     // Iteration starts from 1 to skip the entry block.
     DCHECK_NE(try_block, entry_block_);
-    // Iteration ends at num_blocks - 1 to skip the exit block.
+    // Exit block has not yet been added to the graph at this point.
     DCHECK_NE(try_block, exit_block_);
     // TryBoundary blocks are added at the end of the list and not iterated over.
     DCHECK(!try_block->IsSingleTryBoundary());
 
     // Find the TryItem for this block.
-    const DexFile::TryItem* try_item = GetTryItem(try_block, code_item, can_block_throw);
-    if (try_item == nullptr) {
+    int32_t try_item_idx = DexFile::FindTryItem(code_item, try_block->GetDexPc());
+    if (try_item_idx == -1) {
       continue;
     }
+    const DexFile::TryItem& try_item = *DexFile::GetTryItems(code_item, try_item_idx);
+    uint32_t try_start = try_item.start_addr_;
+    uint32_t try_end = try_start + try_item.insn_count_;
 
     if (try_block->IsCatchBlock()) {
       // Catch blocks are always considered an entry point into the TryItem in
@@ -394,7 +373,7 @@
       DCHECK(split_position != nullptr);
       HBasicBlock* catch_block = try_block;
       try_block = catch_block->SplitBefore(split_position);
-      SplitTryBoundaryEdge(catch_block, try_block, HTryBoundary::kEntry, code_item, *try_item);
+      SplitTryBoundaryEdge(catch_block, try_block, HTryBoundary::kEntry, code_item, try_item);
     } else {
       // For non-catch blocks, find predecessors which are not covered by the
       // same TryItem range. Such edges enter the try block and will have
@@ -406,14 +385,12 @@
           // TryItem. We split it again and insert an entry point.
           if (kIsDebugBuild) {
             HTryBoundary* last_insn = predecessor->GetLastInstruction()->AsTryBoundary();
-            const DexFile::TryItem* predecessor_try_item =
-                GetTryItem(predecessor->GetSinglePredecessor(), code_item, can_block_throw);
             DCHECK(!last_insn->IsEntry());
             DCHECK_EQ(last_insn->GetNormalFlowSuccessor(), try_block);
             DCHECK(try_block->IsFirstIndexOfPredecessor(predecessor, i));
-            DCHECK_NE(try_item, predecessor_try_item);
+            DCHECK(!IsBlockInPcRange(predecessor->GetSinglePredecessor(), try_start, try_end));
           }
-        } else if (GetTryItem(predecessor, code_item, can_block_throw) != try_item) {
+        } else if (!IsBlockInPcRange(predecessor, try_start, try_end)) {
           // This is an entry point into the TryItem and the edge has not been
           // split yet. That means that `predecessor` is not in a TryItem, or
           // it is in a different TryItem and we happened to iterate over this
@@ -422,7 +399,7 @@
           // Not an edge on the boundary of the try block.
           continue;
         }
-        SplitTryBoundaryEdge(predecessor, try_block, HTryBoundary::kEntry, code_item, *try_item);
+        SplitTryBoundaryEdge(predecessor, try_block, HTryBoundary::kEntry, code_item, try_item);
       }
     }
 
@@ -439,13 +416,11 @@
         // TryItem. We split it again and insert an exit.
         if (kIsDebugBuild) {
           HTryBoundary* last_insn = successor->GetLastInstruction()->AsTryBoundary();
-          const DexFile::TryItem* successor_try_item =
-              GetTryItem(last_insn->GetNormalFlowSuccessor(), code_item, can_block_throw);
           DCHECK_EQ(try_block, successor->GetSinglePredecessor());
           DCHECK(last_insn->IsEntry());
-          DCHECK_NE(try_item, successor_try_item);
+          DCHECK(!IsBlockInPcRange(last_insn->GetNormalFlowSuccessor(), try_start, try_end));
         }
-      } else if (GetTryItem(successor, code_item, can_block_throw) != try_item) {
+      } else if (!IsBlockInPcRange(successor, try_start, try_end)) {
         // This is an exit out of the TryItem and the edge has not been split
         // yet. That means that either `successor` is not in a TryItem, or it
         // is in a different TryItem and we happened to iterate over this
@@ -462,7 +437,7 @@
         // Not an edge on the boundary of the try block.
         continue;
       }
-      SplitTryBoundaryEdge(try_block, successor, HTryBoundary::kExit, code_item, *try_item);
+      SplitTryBoundaryEdge(try_block, successor, HTryBoundary::kExit, code_item, try_item);
     }
   }
 }
@@ -521,14 +496,14 @@
   // Add the suspend check to the entry block.
   entry_block_->AddInstruction(new (arena_) HSuspendCheck(0));
   entry_block_->AddInstruction(new (arena_) HGoto());
-  // Add the exit block at the end.
-  graph_->AddBlock(exit_block_);
 
   // Iterate over blocks covered by TryItems and insert TryBoundaries at entry
   // and exit points. This requires all control-flow instructions and
   // non-exceptional edges to have been created.
   InsertTryBoundaryBlocks(code_item);
 
+  // Add the exit block at the end to give it the highest id.
+  graph_->AddBlock(exit_block_);
   return true;
 }
 
diff --git a/compiler/optimizing/builder.h b/compiler/optimizing/builder.h
index 7098eb8..e487255 100644
--- a/compiler/optimizing/builder.h
+++ b/compiler/optimizing/builder.h
@@ -98,6 +98,9 @@
   HBasicBlock* FindBlockStartingAt(int32_t dex_pc) const;
   HBasicBlock* FindOrCreateBlockStartingAt(int32_t dex_pc);
 
+  // Returns whether the dex_pc of `block` lies within the given range.
+  bool IsBlockInPcRange(HBasicBlock* block, uint32_t dex_pc_start, uint32_t dex_pc_end);
+
   // Adds new blocks to `branch_targets_` starting at the limits of TryItems and
   // their exception handlers.
   void CreateBlocksForTryCatch(const DexFile::CodeItem& code_item);
diff --git a/compiler/optimizing/graph_visualizer.cc b/compiler/optimizing/graph_visualizer.cc
index 37c060c..504c141 100644
--- a/compiler/optimizing/graph_visualizer.cc
+++ b/compiler/optimizing/graph_visualizer.cc
@@ -357,10 +357,6 @@
     StartAttributeStream("kind") << barrier->GetBarrierKind();
   }
 
-  void VisitMonitorOperation(HMonitorOperation* monitor) OVERRIDE {
-    StartAttributeStream("kind") << (monitor->IsEnter() ? "enter" : "exit");
-  }
-
   void VisitLoadClass(HLoadClass* load_class) OVERRIDE {
     StartAttributeStream("gen_clinit_check") << std::boolalpha
         << load_class->MustGenerateClinitCheck() << std::noboolalpha;
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index f511897..e4a7aa6 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -4136,14 +4136,8 @@
   }
 
   // Instruction may throw a Java exception, so we need an environment.
-  bool NeedsEnvironment() const OVERRIDE { return CanThrow(); }
-
-  bool CanThrow() const OVERRIDE {
-    // Verifier guarantees that monitor-exit cannot throw.
-    // This is important because it allows the HGraphBuilder to remove
-    // a dead throw-catch loop generated for `synchronized` blocks/methods.
-    return IsEnter();
-  }
+  bool NeedsEnvironment() const OVERRIDE { return true; }
+  bool CanThrow() const OVERRIDE { return true; }
 
   uint32_t GetDexPc() const OVERRIDE { return dex_pc_; }
 
diff --git a/test/510-checker-try-catch/smali/Builder.smali b/test/510-checker-try-catch/smali/Builder.smali
index 87e4064..4ea7b61 100644
--- a/test/510-checker-try-catch/smali/Builder.smali
+++ b/test/510-checker-try-catch/smali/Builder.smali
@@ -713,20 +713,20 @@
 ## CHECK-START: int Builder.testSwitchTryExit(int, int, int, int) builder (after)
 
 ## CHECK:  name             "B0"
-## CHECK:  successors       "<<BEnterTry1:B\d+>>"
+## CHECK:  successors       "<<BEnterTry:B\d+>>"
 
 ## CHECK:  name             "<<BPSwitch0:B\d+>>"
-## CHECK:  predecessors     "<<BEnterTry1>>"
-## CHECK:  successors       "<<BTry2:B\d+>>" "<<BExitTry1:B\d+>>"
+## CHECK:  predecessors     "<<BEnterTry>>"
+## CHECK:  successors       "<<BTry2:B\d+>>" "<<BPSwitch1:B\d+>>"
 ## CHECK:  If
 
-## CHECK:  name             "<<BPSwitch1:B\d+>>"
-## CHECK:  predecessors     "<<BExitTry1>>"
-## CHECK:  successors       "<<BOutside:B\d+>>" "<<BEnterTry2:B\d+>>"
+## CHECK:  name             "<<BPSwitch1>>"
+## CHECK:  predecessors     "<<BPSwitch0>>"
+## CHECK:  successors       "<<BExitTry1:B\d+>>" "<<BTry1:B\d+>>"
 ## CHECK:  If
 
-## CHECK:  name             "<<BTry1:B\d+>>"
-## CHECK:  predecessors     "<<BEnterTry2>>"
+## CHECK:  name             "<<BTry1>>"
+## CHECK:  predecessors     "<<BPSwitch1>>"
 ## CHECK:  successors       "<<BTry2>>"
 ## CHECK:  Div
 
@@ -735,34 +735,28 @@
 ## CHECK:  successors       "<<BExitTry2:B\d+>>"
 ## CHECK:  Div
 
-## CHECK:  name             "<<BOutside>>"
-## CHECK:  predecessors     "<<BPSwitch1>>" "<<BExitTry2>>"
+## CHECK:  name             "<<BOutside:B\d+>>"
+## CHECK:  predecessors     "<<BExitTry1>>" "<<BExitTry2>>"
 ## CHECK:  successors       "<<BCatchReturn:B\d+>>"
 ## CHECK:  Div
 
 ## CHECK:  name             "<<BCatchReturn>>"
-## CHECK:  predecessors     "<<BOutside>>" "<<BEnterTry1>>" "<<BExitTry1>>" "<<BEnterTry2>>" "<<BExitTry2>>"
+## CHECK:  predecessors     "<<BOutside>>" "<<BEnterTry>>" "<<BExitTry1>>" "<<BExitTry2>>"
 ## CHECK:  flags            "catch_block"
 ## CHECK:  Return
 
-## CHECK:  name             "<<BEnterTry1>>"
+## CHECK:  name             "<<BEnterTry>>"
 ## CHECK:  predecessors     "B0"
 ## CHECK:  successors       "<<BPSwitch0>>"
 ## CHECK:  xhandlers        "<<BCatchReturn>>"
 ## CHECK:  TryBoundary      kind:entry
 
 ## CHECK:  name             "<<BExitTry1>>"
-## CHECK:  predecessors     "<<BPSwitch0>>"
-## CHECK:  successors       "<<BPSwitch1>>"
+## CHECK:  predecessors     "<<BPSwitch1>>"
+## CHECK:  successors       "<<BOutside>>"
 ## CHECK:  xhandlers        "<<BCatchReturn>>"
 ## CHECK:  TryBoundary      kind:exit
 
-## CHECK:  name             "<<BEnterTry2>>"
-## CHECK:  predecessors     "<<BPSwitch1>>"
-## CHECK:  successors       "<<BTry1>>"
-## CHECK:  xhandlers        "<<BCatchReturn>>"
-## CHECK:  TryBoundary      kind:entry
-
 ## CHECK:  name             "<<BExitTry2>>"
 ## CHECK:  predecessors     "<<BTry2>>"
 ## CHECK:  successors       "<<BOutside>>"
@@ -773,7 +767,6 @@
     .registers 4
 
     :try_start
-    div-int/2addr p0, p1
     packed-switch p0, :pswitch_data
 
     div-int/2addr p0, p1
@@ -816,10 +809,6 @@
 ## CHECK:  flags            "catch_block"
 ## CHECK:  StoreLocal       [v0,<<Minus1>>]
 
-## CHECK:  name             "<<BExit>>"
-## CHECK:  predecessors     "<<BExitTry>>" "<<BCatch>>"
-## CHECK:  Exit
-
 ## CHECK:  name             "<<BEnterTry>>"
 ## CHECK:  predecessors     "B0"
 ## CHECK:  successors       "<<BTry>>"
@@ -832,6 +821,10 @@
 ## CHECK:  xhandlers        "<<BCatch>>"
 ## CHECK:  TryBoundary      kind:exit
 
+## CHECK:  name             "<<BExit>>"
+## CHECK:  predecessors     "<<BExitTry>>" "<<BCatch>>"
+## CHECK:  Exit
+
 .method public static testThrow(Ljava/lang/Exception;)I
     .registers 2
 
@@ -859,9 +852,6 @@
 
 ## CHECK:  name             "<<BReturn:B\d+>>"
 ## CHECK:  predecessors     "<<BExitTry>>"
-## CHECK:  successors       "<<BExit:B\d+>>"
-
-## CHECK:  name             "<<BExit>>"
 
 ## CHECK:  name             "<<BTry:B\d+>>"
 ## CHECK:  predecessors     "<<BEnterTry>>"
@@ -966,51 +956,48 @@
 ## CHECK:  successors       "<<BCatch1:B\d+>>"
 
 ## CHECK:  name             "<<BCatch1>>"
-## CHECK:  predecessors     "B0" "<<BEnterTry2:B\d+>>" "<<BExitTry2:B\d+>>"
-## CHECK:  successors       "<<BEnterTry1:B\d+>>"
+## CHECK:  predecessors     "B0" "<<BEnter2:B\d+>>" "<<BExit2:B\d+>>"
+## CHECK:  successors       "<<BEnter1:B\d+>>"
 ## CHECK:  flags            "catch_block"
 
 ## CHECK:  name             "<<BCatch2:B\d+>>"
-## CHECK:  predecessors     "<<BExitTry1:B\d+>>" "<<BEnterTry1>>" "<<BExitTry1>>"
-## CHECK:  successors       "<<BEnterTry2>>"
+## CHECK:  predecessors     "<<BExit1:B\d+>>" "<<BEnter1>>" "<<BExit1>>"
+## CHECK:  successors       "<<BEnter2>>"
 ## CHECK:  flags            "catch_block"
 
 ## CHECK:  name             "<<BReturn:B\d+>>"
-## CHECK:  predecessors     "<<BExitTry2>>"
-## CHECK:  successors       "<<BExit:B\d+>>"
+## CHECK:  predecessors     "<<BExit2>>"
 ## CHECK:  Return
 
-## CHECK:  name             "<<BExit>>"
-
 ## CHECK:  name             "<<BTry1:B\d+>>"
-## CHECK:  predecessors     "<<BEnterTry1>>"
-## CHECK:  successors       "<<BExitTry1>>"
+## CHECK:  predecessors     "<<BEnter1>>"
+## CHECK:  successors       "<<BExit1>>"
 ## CHECK:  Div
 
-## CHECK:  name             "<<BEnterTry1>>"
+## CHECK:  name             "<<BEnter1>>"
 ## CHECK:  predecessors     "<<BCatch1>>"
 ## CHECK:  successors       "<<BTry1>>"
 ## CHECK:  xhandlers        "<<BCatch2>>"
 ## CHECK:  TryBoundary      kind:entry
 
-## CHECK:  name             "<<BExitTry1>>"
+## CHECK:  name             "<<BExit1>>"
 ## CHECK:  predecessors     "<<BTry1>>"
 ## CHECK:  successors       "<<BCatch2>>"
 ## CHECK:  xhandlers        "<<BCatch2>>"
 ## CHECK:  TryBoundary      kind:exit
 
 ## CHECK:  name             "<<BTry2:B\d+>>"
-## CHECK:  predecessors     "<<BEnterTry2>>"
-## CHECK:  successors       "<<BExitTry2>>"
+## CHECK:  predecessors     "<<BEnter2>>"
+## CHECK:  successors       "<<BExit2>>"
 ## CHECK:  Div
 
-## CHECK:  name             "<<BEnterTry2>>"
+## CHECK:  name             "<<BEnter2>>"
 ## CHECK:  predecessors     "<<BCatch2>>"
 ## CHECK:  successors       "<<BTry2>>"
 ## CHECK:  xhandlers        "<<BCatch1>>"
 ## CHECK:  TryBoundary      kind:entry
 
-## CHECK:  name             "<<BExitTry2>>"
+## CHECK:  name             "<<BExit2>>"
 ## CHECK:  predecessors     "<<BTry2>>"
 ## CHECK:  successors       "<<BReturn>>"
 ## CHECK:  xhandlers        "<<BCatch1>>"
@@ -1144,29 +1131,3 @@
     :try_end
     .catchall {:try_start .. :try_end} :catch_all
 .end method
-
-## CHECK-START: int Builder.testSynchronized(java.lang.Object) builder (after)
-## CHECK:      flags "catch_block"
-## CHECK-NOT:  end_block
-## CHECK:      MonitorOperation kind:exit
-
-.method public static testSynchronized(Ljava/lang/Object;)I
-  .registers 2
-
-  monitor-enter p0
-
-  :try_start_9
-  invoke-virtual {p0}, Ljava/lang/Object;->hashCode()I
-  move-result v0
-
-  monitor-exit p0
-  return v0
-
-  :catchall_11
-  move-exception v0
-  monitor-exit p0
-  :try_end_15
-  .catchall {:try_start_9 .. :try_end_15} :catchall_11
-
-  throw v0
-.end method