Unify SoftDeoptimize and Deoptimize hydrogen instructions

src/hydrogen.h

Index: src/hydrogen.h
diff --git a/src/hydrogen.h b/src/hydrogen.h
index 797b444078d5e838157c77e207a956a4b3d056db..ed1eaf1a21e95a9cc25a9a3f72c2d00491cc46f9 100644
--- a/src/hydrogen.h
+++ b/src/hydrogen.h
@@ -137,17 +137,15 @@ class HBasicBlock: public ZoneObject {
   }
 
   int PredecessorIndexOf(HBasicBlock* predecessor) const;
-  void AddSimulate(BailoutId ast_id,
-                   RemovableSimulate removable = FIXED_SIMULATE) {
-    AddInstruction(CreateSimulate(ast_id, removable));
+  HSimulate* AddSimulate(BailoutId ast_id,
+                         RemovableSimulate removable = FIXED_SIMULATE) {
+    HSimulate* instr = CreateSimulate(ast_id, removable);
+    AddInstruction(instr);
+    return instr;
   }
   void AssignCommonDominator(HBasicBlock* other);
   void AssignLoopSuccessorDominators();
 
-  void FinishExitWithDeoptimization(HDeoptimize::UseEnvironment has_uses) {
-    FinishExit(CreateDeoptimize(has_uses));
-  }
-
   // Add the inlined function exit sequence, adding an HLeaveInlined
   // instruction and updating the bailout environment.
   void AddLeaveInlined(HValue* return_value, FunctionState* state);
@@ -182,11 +180,12 @@ class HBasicBlock: public ZoneObject {
 #endif
 
  private:
+  friend class HGraphBuilder;
+
   void RegisterPredecessor(HBasicBlock* pred);
   void AddDominatedBlock(HBasicBlock* block);
 
   HSimulate* CreateSimulate(BailoutId ast_id, RemovableSimulate removable);
-  HDeoptimize* CreateDeoptimize(HDeoptimize::UseEnvironment has_uses);
 
   int block_id_;
   HGraph* graph_;
@@ -1023,11 +1022,6 @@ class HGraphBuilder {
             new(zone()) I(p1, p2, p3, p4, p5, p6, p7, p8)));
   }
 
-  void AddSimulate(BailoutId id,
-                   RemovableSimulate removable = FIXED_SIMULATE);
-
-  HReturn* AddReturn(HValue* value);
-
   void IncrementInNoSideEffectsScope() {
     no_side_effects_scope_count_++;
   }
@@ -1118,12 +1112,7 @@ class HGraphBuilder {
 
   HValue* AddLoadJSBuiltin(Builtins::JavaScript builtin, HValue* context);
 
-  enum SoftDeoptimizeMode {
-    MUST_EMIT_SOFT_DEOPT,
-    CAN_OMIT_SOFT_DEOPT
-  };
-
-  void AddSoftDeoptimize(SoftDeoptimizeMode mode = CAN_OMIT_SOFT_DEOPT);
+  void FinishExitWithHardDeoptimization(HBasicBlock* continuation);
 
   class IfBuilder {
    public:
@@ -1228,7 +1217,6 @@ class HGraphBuilder {
     void ElseDeopt() {
       Else();
       Deopt();
-      End();
     }
 
     void Return(HValue* value);
@@ -1241,6 +1229,8 @@ class HGraphBuilder {
     HGraphBuilder* builder_;
     int position_;
     bool finished_ : 1;
+    bool deopt_then_ : 1;
+    bool deopt_else_ : 1;
     bool did_then_ : 1;
     bool did_else_ : 1;
     bool did_and_ : 1;
@@ -1422,12 +1412,68 @@ class HGraphBuilder {
 
  private:
   HGraphBuilder();
+
+  void PadEnvironmentForContinuation(HBasicBlock* from,
+                                     HBasicBlock* continuation);
+
   CompilationInfo* info_;
   HGraph* graph_;
   HBasicBlock* current_block_;
   int no_side_effects_scope_count_;
 };
 
+
+template<>
+inline HDeoptimize* HGraphBuilder::Add(Deoptimizer::BailoutType type) {
+  if (type == Deoptimizer::SOFT) {
+    isolate()->counters()->soft_deopts_requested()->Increment();
+    if (FLAG_always_opt) return NULL;
+  }
+  if (current_block()->IsDeoptimizing()) return NULL;
+  HDeoptimize* instr = new(zone()) HDeoptimize(type);
+  AddInstruction(instr);
+  if (type == Deoptimizer::SOFT) {
+    isolate()->counters()->soft_deopts_inserted()->Increment();
+    graph()->set_has_soft_deoptimize(true);
+  }
+  current_block()->MarkAsDeoptimizing();
+  return instr;
+}
+
+
+template<>
+inline HSimulate* HGraphBuilder::Add(BailoutId id,
+                                     RemovableSimulate removable) {
+  HSimulate* instr = current_block()->CreateSimulate(id, removable);
+  AddInstruction(instr);
+  return instr;
+}
+
+
+template<>
+inline HSimulate* HGraphBuilder::Add(BailoutId id) {
+  return Add<HSimulate>(id, FIXED_SIMULATE);
+}
+
+
+template<>
+inline HReturn* HGraphBuilder::Add(HValue* value) {
+  HValue* context = environment()->LookupContext();
+  int num_parameters = graph()->info()->num_parameters();
+  HValue* params = Add<HConstant>(num_parameters);
+  HReturn* return_instruction = new(graph()->zone())
+      HReturn(value, context, params);
+  current_block()->FinishExit(return_instruction);
+  return return_instruction;
+}
+
+
+template<>
+inline HReturn* HGraphBuilder::Add(HConstant* p1) {
+  return Add<HReturn>(static_cast<HValue*>(p1));
+}
+
+
 class HOptimizedGraphBuilder: public HGraphBuilder, public AstVisitor {
  public:
   // A class encapsulating (lazily-allocated) break and continue blocks for