Stop attaching try_index to individual instructions put it at block entry instead.

runtime/vm/flow_graph_compiler_x64.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_FLOW_GRAPH_COMPILER_X64_H_
 #define VM_FLOW_GRAPH_COMPILER_X64_H_
 
 #ifndef VM_FLOW_GRAPH_COMPILER_H_
 #error Include flow_graph_compiler.h instead of flow_graph_compiler_x64.h.
 #endif
@@ skipping 61 matching lines @@
                             Register reg,
                             Register temp,
                             Label* not_double_or_smi);
 
   // Returns 'true' if code generation for this function is complete, i.e.,
   // no fall-through to regular code is needed.
   bool TryIntrinsify();
 
   void GenerateCallRuntime(intptr_t deopt_id,
                            intptr_t token_pos,
-                           intptr_t try_index,
                            const RuntimeEntry& entry,
                            LocationSummary* locs);
 
   void GenerateCall(intptr_t token_pos,
-                    intptr_t try_index,
                     const ExternalLabel* label,
                     PcDescriptors::Kind kind,
                     LocationSummary* locs);
 
   void GenerateAssertAssignable(intptr_t deopt_id,
                                 intptr_t token_pos,
-                                intptr_t try_index,
                                 const AbstractType& dst_type,
                                 const String& dst_name,
                                 LocationSummary* locs);
 
   void GenerateInstanceOf(intptr_t deopt_id,
                           intptr_t token_pos,
-                          intptr_t try_index,
                           const AbstractType& type,
                           bool negate_result,
                           LocationSummary* locs);
 
   void GenerateInstanceCall(intptr_t deopt_id,
                             intptr_t token_pos,
-                            intptr_t try_index,
                             const String& function_name,
                             intptr_t argument_count,
                             const Array& argument_names,
                             intptr_t checked_argument_count,
                             LocationSummary* locs);
 
   void GenerateStaticCall(intptr_t deopt_id,
                           intptr_t token_pos,
-                          intptr_t try_index,
                           const Function& function,
                           intptr_t argument_count,
                           const Array& argument_names,
                           LocationSummary* locs);
 
   void GenerateInlinedMathSqrt(Label* done);
 
   void GenerateNumberTypeCheck(Register kClassIdReg,
                                const AbstractType& type,
                                Label* is_instance_lbl,
@@ skipping 10 matching lines @@
                             Register instance_reg,
                             Register temp_reg,
                             Label* deopt);
 
   void EmitInstanceCall(ExternalLabel* target_label,
                         const ICData& ic_data,
                         const Array& arguments_descriptor,
                         intptr_t argument_count,
                         intptr_t deopt_id,
                         intptr_t token_pos,
-                        intptr_t try_index,
                         LocationSummary* locs);
 
   void EmitTestAndCall(const ICData& ic_data,
                        Register class_id_reg,
                        intptr_t arg_count,
                        const Array& arg_names,
                        Label* deopt,
                        intptr_t deopt_id,
                        intptr_t token_index,
-                       intptr_t try_index,
                        LocationSummary* locs);
 
   void EmitDoubleCompareBranch(Condition true_condition,
                                XmmRegister left,
                                XmmRegister right,
                                BranchInstr* branch);
   void EmitDoubleCompareBool(Condition true_condition,
                              XmmRegister left,
                              XmmRegister right,
                              Register result);
 
   intptr_t StackSize() const;
 
   // Returns assembler label associated with the given block entry.
   Label* GetBlockLabel(BlockEntryInstr* block_entry) const;
 
   // Returns true if there is a next block after the current one in
   // the block order and if it is the given block.
   bool IsNextBlock(BlockEntryInstr* block_entry) const;
 
   void AddExceptionHandler(intptr_t try_index, intptr_t pc_offset);
   void AddCurrentDescriptor(PcDescriptors::Kind kind,
                             intptr_t deopt_id,
-                            intptr_t token_pos,
-                            intptr_t try_index);
+                            intptr_t token_pos);
 
   void RecordSafepoint(LocationSummary* locs);
 
   Label* AddDeoptStub(intptr_t deopt_id, DeoptReasonId reason);
 
   void AddDeoptIndexAtCall(intptr_t deopt_id, intptr_t token_pos);
 
   void AddSlowPathCode(SlowPathCode* slow_path);
 
   void FinalizeExceptionHandlers(const Code& code);
   void FinalizePcDescriptors(const Code& code);
   void FinalizeDeoptInfo(const Code& code);
   void FinalizeStackmaps(const Code& code);
   void FinalizeVarDescriptors(const Code& code);
   void FinalizeComments(const Code& code);
 
   const Bool& bool_true() const { return bool_true_; }
   const Bool& bool_false() const { return bool_false_; }
   const Class& double_class() const { return double_class_; }
 
   // Returns true if the compiled function has a finally clause.
   bool HasFinally() const;
 
   static const int kLocalsOffsetFromFP = (-1 * kWordSize);
 
   void SaveLiveRegisters(LocationSummary* locs);
   void RestoreLiveRegisters(LocationSummary* locs);
 
+  intptr_t CurrentTryIndex() const {
+    if (current_block_ == NULL) {
+      return CatchClauseNode::kInvalidTryIndex;
+    }
+    return current_block_->try_index();
+  }
+
  private:
   friend class DeoptimizationStub;
 
   void GenerateDeferredCode();
 
   void EmitInstructionPrologue(Instruction* instr);
 
   // Emit code to load a Value into register 'dst'.
   void LoadValue(Register dst, Value* value);
 
   void EmitStaticCall(const Function& function,
                       const Array& arguments_descriptor,
                       intptr_t argument_count,
                       intptr_t deopt_id,
                       intptr_t token_pos,
-                      intptr_t try_index,
                       LocationSummary* locs);
 
   // Type checking helper methods.
   void CheckClassIds(Register class_id_reg,
                      const GrowableArray<intptr_t>& class_ids,
                      Label* is_instance_lbl,
                      Label* is_not_instance_lbl);
 
   RawSubtypeTestCache* GenerateInlineInstanceof(intptr_t token_pos,
                                                 const AbstractType& type,
@@ skipping 86 matching lines @@
   // that should be used when deoptimizing we store it in this variable.
   // In future AddDeoptStub should be moved out of the instruction template.
   Environment* pending_deoptimization_env_;
 
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_COMPILER_X64_H_