SSI implementation.

src/hydrogen.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 143 matching lines @@
 
   bool IsLoopSuccessorDominator() const {
     return dominates_loop_successors_;
   }
   void MarkAsLoopSuccessorDominator() {
     dominates_loop_successors_ = true;
   }
 
   inline Zone* zone() const;
 
+  void BuildSsiRecursively() {
+    BuildSsi();
+    for (int i = 0; i < dominated_blocks()->length(); ++i) {
+      dominated_blocks()->at(i)->BuildSsiRecursively();
+    }
+  }
+  void BuildSsi() {
+    for (int i = 0; i < phis()->length(); i++) {
+      HPhi* current = phis()->at(i);
+      current->SetFlag(HValue::kProcessedBySsi);
+      current->BuildSsi();
+    }
+
+    for (HInstruction* current = first();
+        current != NULL;
+        current = current->next()) {
+      // We set the flag before calling BuildSsi so that, while creating new
+      // SSI definitions, uses inside current will not be updated.
+      current->SetFlag(HValue::kProcessedBySsi);
+      current->BuildSsi();
+    }
+  }
+
 #ifdef DEBUG
   void Verify();
 #endif
 
  private:
   void RegisterPredecessor(HBasicBlock* pred);
   void AddDominatedBlock(HBasicBlock* block);
 
   HSimulate* CreateSimulate(BailoutId ast_id, RemovableSimulate removable);
   HDeoptimize* CreateDeoptimize(HDeoptimize::UseEnvironment has_uses);
@@ skipping 109 matching lines @@
   // Returns false if there are phi-uses of an uninitialized const
   // which are not supported by the optimizing compiler.
   bool CheckConstPhiUses();
 
   void CollectPhis();
 
   void set_undefined_constant(HConstant* constant) {
     undefined_constant_.set(constant);
   }
   HConstant* GetConstantUndefined() const { return undefined_constant_.get(); }
+  HConstant* GetConstant0();
   HConstant* GetConstant1();
   HConstant* GetConstantMinus1();
   HConstant* GetConstantTrue();
   HConstant* GetConstantFalse();
   HConstant* GetConstantHole();
 
   HBasicBlock* CreateBasicBlock();
   HArgumentsObject* GetArgumentsObject() const {
     return arguments_object_.get();
   }
@@ skipping 60 matching lines @@
     return is_recursive_;
   }
 
   void RecordUint32Instruction(HInstruction* instr) {
     if (uint32_instructions_ == NULL) {
       uint32_instructions_ = new(zone()) ZoneList<HInstruction*>(4, zone());
     }
     uint32_instructions_->Add(instr, zone());
   }
 
+  void BuildSsi();
+  void CleanupSsi();
+
  private:
   HConstant* GetConstant(SetOncePointer<HConstant>* pointer,
                          Handle<Object> value);
   HConstant* GetConstantInt32(SetOncePointer<HConstant>* pointer,
                               int32_t integer_value);
 
   void MarkAsDeoptimizingRecursively(HBasicBlock* block);
   void InsertTypeConversions(HInstruction* instr);
   void PropagateMinusZeroChecks(HValue* value, BitVector* visited);
   void RecursivelyMarkPhiDeoptimizeOnUndefined(HPhi* phi);
   void InsertRepresentationChangeForUse(HValue* value,
                                         HValue* use_value,
                                         int use_index,
                                         Representation to);
   void InsertRepresentationChangesForValue(HValue* value);
   void InferTypes(ZoneList<HValue*>* worklist);
   void InitializeInferredTypes(int from_inclusive, int to_inclusive);
   void CheckForBackEdge(HBasicBlock* block, HBasicBlock* successor);
   void EliminateRedundantBoundsChecks(HBasicBlock* bb, BoundsCheckTable* table);
 
   Isolate* isolate_;
   int next_block_id_;
   HBasicBlock* entry_block_;
   HEnvironment* start_environment_;
   ZoneList<HBasicBlock*> blocks_;
   ZoneList<HValue*> values_;
   ZoneList<HPhi*>* phi_list_;
   ZoneList<HInstruction*>* uint32_instructions_;
   SetOncePointer<HConstant> undefined_constant_;
+  SetOncePointer<HConstant> constant_0_;
   SetOncePointer<HConstant> constant_1_;
   SetOncePointer<HConstant> constant_minus1_;
   SetOncePointer<HConstant> constant_true_;
   SetOncePointer<HConstant> constant_false_;
   SetOncePointer<HConstant> constant_hole_;
   SetOncePointer<HArgumentsObject> arguments_object_;
 
   SetOncePointer<HBasicBlock> osr_loop_entry_;
   SetOncePointer<ZoneList<HUnknownOSRValue*> > osr_values_;
 
@@ skipping 1143 matching lines @@
   const char* filename_;
   HeapStringAllocator string_allocator_;
   StringStream trace_;
   int indent_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_