HStoreNamedField for Smis optimized for x64

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index c6d5a147a76ac8e484273753421cb459158d7500..5a5fbc62739c15af33b71e043a2a68e04507fae6 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -3930,13 +3930,14 @@ void LCodeGen::DoInnerAllocatedObject(LInnerAllocatedObject* instr) {
 
 
 void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
+  HStoreNamedField* hinstr = instr->hydrogen();
   Representation representation = instr->representation();
 
-  HObjectAccess access = instr->hydrogen()->access();
+  HObjectAccess access = hinstr->access();
   int offset = access.offset();
 
   if (access.IsExternalMemory()) {
-    ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
+    ASSERT(!hinstr->NeedsWriteBarrier());
     Register value = ToRegister(instr->value());
     if (instr->object()->IsConstantOperand()) {
       ASSERT(value.is(rax));
@@ -3956,7 +3957,8 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   if (FLAG_track_fields && representation.IsSmi()) {
     if (instr->value()->IsConstantOperand()) {
       LConstantOperand* operand_value = LConstantOperand::cast(instr->value());
-      if (!IsSmiConstant(operand_value)) {
+      if (!IsInteger32Constant(operand_value) &&
+          !IsSmiConstant(operand_value)) {
         DeoptimizeIf(no_condition, instr->environment());
       }
     }
@@ -3967,7 +3969,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
         DeoptimizeIf(no_condition, instr->environment());
       }
     } else {
-      if (!instr->hydrogen()->value()->type().IsHeapObject()) {
+      if (!hinstr->value()->type().IsHeapObject()) {
         Register value = ToRegister(instr->value());
         Condition cc = masm()->CheckSmi(value);
         DeoptimizeIf(cc, instr->environment());
@@ -3976,14 +3978,14 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   } else if (FLAG_track_double_fields && representation.IsDouble()) {
     ASSERT(transition.is_null());
     ASSERT(access.IsInobject());
-    ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
+    ASSERT(!hinstr->NeedsWriteBarrier());
     XMMRegister value = ToDoubleRegister(instr->value());
     __ movsd(FieldOperand(object, offset), value);
     return;
   }
 
   if (!transition.is_null()) {
-    if (!instr->hydrogen()->NeedsWriteBarrierForMap()) {
+    if (!hinstr->NeedsWriteBarrierForMap()) {
       __ Move(FieldOperand(object, HeapObject::kMapOffset), transition);
     } else {
       Register temp = ToRegister(instr->temp());
@@ -4001,9 +4003,8 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   }
 
   // Do the store.
-  SmiCheck check_needed =
-      instr->hydrogen()->value()->IsHeapObject()
-          ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
+  SmiCheck check_needed = hinstr->value()->IsHeapObject()
+                          ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
 
   Register write_register = object;
   if (!access.IsInobject()) {
@@ -4011,26 +4012,41 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
     __ movq(write_register, FieldOperand(object, JSObject::kPropertiesOffset));
   }
 
-  if (instr->value()->IsConstantOperand()) {
+  if (representation.IsSmi() &&
+      hinstr->value()->representation().IsInteger32()) {
+    ASSERT(hinstr->store_mode() == STORE_TO_INITIALIZED_ENTRY);
+    // Store int value directly to upper half of the smi.
+    STATIC_ASSERT(kSmiTag == 0);
+    STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 32);
+    offset += kPointerSize / 2;
+    representation = Representation::Integer32();
+  }
+
+  Operand operand = FieldOperand(write_register, offset);
+
+  if (instr->value()->IsRegister()) {
+    Register value = ToRegister(instr->value());
+    __ Store(operand, value, representation);
+  } else {
     LConstantOperand* operand_value = LConstantOperand::cast(instr->value());
-    if (operand_value->IsRegister()) {
-      Register value = ToRegister(operand_value);
-      __ Store(FieldOperand(write_register, offset), value, representation);
-    } else if (representation.IsInteger32()) {
+    if (IsInteger32Constant(operand_value)) {
+      ASSERT(!hinstr->NeedsWriteBarrier());
       int32_t value = ToInteger32(operand_value);
-      ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
-      __ movl(FieldOperand(write_register, offset), Immediate(value));
+      if (representation.IsSmi()) {
+        __ Move(operand, Smi::FromInt(value));
+
+      } else {
+        __ movl(operand, Immediate(value));
+      }
+
     } else {
       Handle<Object> handle_value = ToHandle(operand_value);
-      ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
-      __ Move(FieldOperand(write_register, offset), handle_value);
+      ASSERT(!hinstr->NeedsWriteBarrier());
+      __ Move(operand, handle_value);
     }
-  } else {
-    Register value = ToRegister(instr->value());
-    __ Store(FieldOperand(write_register, offset), value, representation);
   }
 
-  if (instr->hydrogen()->NeedsWriteBarrier()) {
+  if (hinstr->NeedsWriteBarrier()) {
     Register value = ToRegister(instr->value());
     Register temp = access.IsInobject() ? ToRegister(instr->temp()) : object;
     // Update the write barrier for the object for in-object properties.