Merged r16128, r16135, r16136 into trunk branch.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index eac5173f7d00748bec37cba8a7bb68990113342c..78e9a6b192a3e477b1633cfbfc9dc538dd1370e8 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -2775,6 +2775,21 @@ class HUnaryMathOperation: public HTemplateInstruction<2> {
     }
   }
 
+  virtual void UpdateRepresentation(Representation new_rep,
+                                    HInferRepresentationPhase* h_infer,
+                                    const char* reason) {
+    if (flexible_int() && !new_rep.IsSmi()) {
+      new_rep = Representation::Integer32();
+    }
+    HValue::UpdateRepresentation(new_rep, h_infer, reason);
+  }
+
+  virtual void RepresentationChanged(Representation new_rep) {
+    if (flexible_int() && new_rep.IsInteger32()) {
+      ClearFlag(kFlexibleRepresentation);
+    }
+  }
+
   virtual Range* InferRange(Zone* zone);
 
   virtual HValue* Canonicalize();
@@ -2792,6 +2807,10 @@ class HUnaryMathOperation: public HTemplateInstruction<2> {
   }
 
  private:
+  bool flexible_int() {
+    return op_ == kMathFloor || op_ == kMathRound;
+  }
+
   HUnaryMathOperation(HValue* context, HValue* value, BuiltinFunctionId op)
       : HTemplateInstruction<2>(HType::TaggedNumber()), op_(op) {
     SetOperandAt(0, context);
@@ -2799,8 +2818,8 @@ class HUnaryMathOperation: public HTemplateInstruction<2> {
     switch (op) {
       case kMathFloor:
       case kMathRound:
-        // TODO(verwaest): Set representation to flexible int starting as smi.
-        set_representation(Representation::Integer32());
+        set_representation(Representation::Smi());
+        SetFlag(kFlexibleRepresentation);
         break;
       case kMathAbs:
         // Not setting representation here: it is None intentionally.
@@ -3439,7 +3458,7 @@ class HPhi: public HValue {
       non_phi_uses_[i] = 0;
       indirect_uses_[i] = 0;
     }
-    ASSERT(merged_index >= 0);
+    ASSERT(merged_index >= 0 || merged_index == kInvalidMergedIndex);
     SetFlag(kFlexibleRepresentation);
     SetFlag(kAllowUndefinedAsNaN);
   }
@@ -3462,6 +3481,7 @@ class HPhi: public HValue {
   bool HasRealUses();
 
   bool IsReceiver() const { return merged_index_ == 0; }
+  bool HasMergedIndex() const { return merged_index_ != kInvalidMergedIndex; }
 
   int merged_index() const { return merged_index_; }
 
@@ -3526,6 +3546,9 @@ class HPhi: public HValue {
 
   void SimplifyConstantInputs();
 
+  // Marker value representing an invalid merge index.
+  static const int kInvalidMergedIndex = -1;
+
  protected:
   virtual void DeleteFromGraph();
   virtual void InternalSetOperandAt(int index, HValue* value) {