Improvements for x87 stack handling

src/ia32/lithium-ia32.h

Index: src/ia32/lithium-ia32.h
diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index 4c188c3fe849c0d32cf087138918f189e92ebbb5..80b8b37e90d7e0fcde19847ef3edd50ebd5c92b3 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -74,6 +74,7 @@ class LCodeGen;
   V(ClampDToUint8)                              \
   V(ClampIToUint8)                              \
   V(ClampTToUint8)                              \
+  V(ClampTToUint8NoSSE2)                        \
   V(ClassOfTestAndBranch)                       \
   V(CmpIDAndBranch)                             \
   V(CmpObjectEqAndBranch)                       \
@@ -167,6 +168,7 @@ class LCodeGen;
   V(StringLength)                               \
   V(SubI)                                       \
   V(TaggedToI)                                  \
+  V(TaggedToINoSSE2)                            \
   V(ThisFunction)                               \
   V(Throw)                                      \
   V(ToFastProperties)                           \
@@ -265,6 +267,9 @@ class LInstruction: public ZoneObject {
   virtual bool HasResult() const = 0;
   virtual LOperand* result() = 0;
 
+  bool HasDoubleRegisterResult();
+  bool HasDoubleRegisterInput();
+
   LOperand* FirstInput() { return InputAt(0); }
   LOperand* Output() { return HasResult() ? result() : NULL; }
 
@@ -1088,6 +1093,10 @@ class LConstantD: public LTemplateInstruction<1, 0, 1> {
     temps_[0] = temp;
   }
 
+  virtual bool ClobbersDoubleRegisters() const {
+    return false;
+  }
+
   LOperand* temp() { return temps_[0]; }
 
   DECLARE_CONCRETE_INSTRUCTION(ConstantD, "constant-d")
@@ -2018,6 +2027,31 @@ class LTaggedToI: public LTemplateInstruction<1, 1, 1> {
 };
 
 
+// Truncating conversion from a tagged value to an int32.
+class LTaggedToINoSSE2: public LTemplateInstruction<1, 1, 3> {
+ public:
+  LTaggedToINoSSE2(LOperand* value,
+                   LOperand* temp1,
+                   LOperand* temp2,
+                   LOperand* temp3) {
+    inputs_[0] = value;
+    temps_[0] = temp1;
+    temps_[1] = temp2;
+    temps_[2] = temp3;
+  }
+
+  LOperand* value() { return inputs_[0]; }
+  LOperand* scratch() { return temps_[0]; }
+  LOperand* scratch2() { return temps_[1]; }
+  LOperand* scratch3() { return temps_[2]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(TaggedToINoSSE2, "tagged-to-i-nosse2")
+  DECLARE_HYDROGEN_ACCESSOR(UnaryOperation)
+
+  bool truncating() { return hydrogen()->CanTruncateToInt32(); }
+};
+
+
 class LSmiTag: public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LSmiTag(LOperand* value) {
@@ -2040,6 +2074,10 @@ class LNumberUntagD: public LTemplateInstruction<1, 1, 1> {
   LOperand* value() { return inputs_[0]; }
   LOperand* temp() { return temps_[0]; }
 
+  virtual bool ClobbersDoubleRegisters() const {
+    return false;
+  }
+
   DECLARE_CONCRETE_INSTRUCTION(NumberUntagD, "double-untag")
   DECLARE_HYDROGEN_ACCESSOR(Change);
 };
@@ -2380,6 +2418,30 @@ class LClampTToUint8: public LTemplateInstruction<1, 1, 1> {
 };
 
 
+// Truncating conversion from a tagged value to an int32.
+class LClampTToUint8NoSSE2: public LTemplateInstruction<1, 1, 3> {
+ public:
+  LClampTToUint8NoSSE2(LOperand* unclamped,
+                       LOperand* temp1,
+                       LOperand* temp2,
+                       LOperand* temp3) {
+    inputs_[0] = unclamped;
+    temps_[0] = temp1;
+    temps_[1] = temp2;
+    temps_[2] = temp3;
+  }
+
+  LOperand* unclamped() { return inputs_[0]; }
+  LOperand* scratch() { return temps_[0]; }
+  LOperand* scratch2() { return temps_[1]; }
+  LOperand* scratch3() { return temps_[2]; }
+
+  DECLARE_CONCRETE_INSTRUCTION(ClampTToUint8NoSSE2,
+                               "clamp-t-to-uint8-nosse2")
+  DECLARE_HYDROGEN_ACCESSOR(UnaryOperation)
+};
+
+
 class LCheckNonSmi: public LTemplateInstruction<0, 1, 0> {
  public:
   explicit LCheckNonSmi(LOperand* value) {
@@ -2742,6 +2804,7 @@ class LChunkBuilder BASE_EMBEDDED {
   MUST_USE_RESULT LOperand* UseFixed(HValue* value, Register fixed_register);
   MUST_USE_RESULT LOperand* UseFixedDouble(HValue* value,
                                            XMMRegister fixed_register);
+  MUST_USE_RESULT LOperand* UseX87TopOfStack(HValue* value);
 
   // A value that is guaranteed to be allocated to a register.
   // Operand created by UseRegister is guaranteed to be live until the end of
@@ -2827,6 +2890,8 @@ class LChunkBuilder BASE_EMBEDDED {
   LInstruction* DoArithmeticT(Token::Value op,
                               HArithmeticBinaryOperation* instr);
 
+  LOperand* GetStoreKeyedValueOperand(HStoreKeyed* instr);
+
   LPlatformChunk* chunk_;
   CompilationInfo* info_;
   HGraph* const graph_;