HStoreNamedField for Smis optimized for x64

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/108413003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18360 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 6d595ad..f82789f 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -6503,10 +6503,20 @@ class HLoadKeyedGeneric V8_FINAL : public HTemplateInstruction<3> {
 };
 
 
+// Indicates whether the store is a store to an entry that was previously
+// initialized or not.
+enum StoreFieldOrKeyedMode {
+  INITIALIZING_STORE,
+  STORE_TO_INITIALIZED_ENTRY
+};
+
+
 class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
  public:
   DECLARE_INSTRUCTION_FACTORY_P3(HStoreNamedField, HValue*,
                                  HObjectAccess, HValue*);
+  DECLARE_INSTRUCTION_FACTORY_P4(HStoreNamedField, HValue*,
+                                 HObjectAccess, HValue*, StoreFieldOrKeyedMode);
 
   DECLARE_CONCRETE_INSTRUCTION(StoreNamedField)
 
@@ -6527,8 +6537,12 @@ class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
           field_representation().IsUInteger16() ||
           field_representation().IsInteger32()) {
         return Representation::Integer32();
-      } else if (field_representation().IsDouble() ||
-                 field_representation().IsSmi()) {
+      } else if (field_representation().IsDouble()) {
+        return field_representation();
+      } else if (field_representation().IsSmi()) {
+        if (SmiValuesAre32Bits() && store_mode_ == STORE_TO_INITIALIZED_ENTRY) {
+          return Representation::Integer32();
+        }
         return field_representation();
       } else if (field_representation().IsExternal()) {
         return Representation::External();
@@ -6555,6 +6569,7 @@ class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
   HObjectAccess access() const { return access_; }
   HValue* new_space_dominator() const { return new_space_dominator_; }
   bool has_transition() const { return has_transition_; }
+  StoreFieldOrKeyedMode store_mode() const { return store_mode_; }
 
   Handle<Map> transition_map() const {
     if (has_transition()) {
@@ -6605,11 +6620,13 @@ class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
  private:
   HStoreNamedField(HValue* obj,
                    HObjectAccess access,
-                   HValue* val)
+                   HValue* val,
+                   StoreFieldOrKeyedMode store_mode = INITIALIZING_STORE)
       : access_(access),
         new_space_dominator_(NULL),
         write_barrier_mode_(UPDATE_WRITE_BARRIER),
-        has_transition_(false) {
+        has_transition_(false),
+        store_mode_(store_mode) {
     SetOperandAt(0, obj);
     SetOperandAt(1, val);
     SetOperandAt(2, obj);
@@ -6620,6 +6637,7 @@ class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
   HValue* new_space_dominator_;
   WriteBarrierMode write_barrier_mode_ : 1;
   bool has_transition_ : 1;
+  StoreFieldOrKeyedMode store_mode_ : 1;
 };
 
 

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 339a623..4adaba3 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -5206,9 +5206,9 @@ HInstruction* HOptimizedGraphBuilder::BuildStoreNamedField(
     }
   } else {
     // This is a normal store.
-    instr = New<HStoreNamedField>(checked_object->ActualValue(),
-                                  field_access,
-                                  value);
+    instr = New<HStoreNamedField>(
+        checked_object->ActualValue(), field_access, value,
+        transition_to_field ? INITIALIZING_STORE : STORE_TO_INITIALIZED_ENTRY);
   }
 
   if (transition_to_field) {
@@ -9441,7 +9441,7 @@ void HOptimizedGraphBuilder::BuildEmitInObjectProperties(
       Add<HStoreNamedField>(object, access, result);
     } else {
       Representation representation = details.representation();
-      HInstruction* value_instruction = Add<HConstant>(value);
+      HInstruction* value_instruction;
 
       if (representation.IsDouble()) {
         // Allocate a HeapNumber box and store the value into it.
@@ -9456,8 +9456,12 @@ void HOptimizedGraphBuilder::BuildEmitInObjectProperties(
         AddStoreMapConstant(double_box,
             isolate()->factory()->heap_number_map());
         Add<HStoreNamedField>(double_box, HObjectAccess::ForHeapNumberValue(),
-            value_instruction);
+                              Add<HConstant>(value));
         value_instruction = double_box;
+      } else if (representation.IsSmi() && value->IsUninitialized()) {
+        value_instruction = graph()->GetConstant0();
+      } else {
+        value_instruction = Add<HConstant>(value);
       }
 
       Add<HStoreNamedField>(object, access, value_instruction);

diff --git a/src/objects-inl.h b/src/objects-inl.h
index d488fc0..994c991 100644 (file)
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -267,6 +267,9 @@ bool Object::HasValidElements() {
 
 MaybeObject* Object::AllocateNewStorageFor(Heap* heap,
                                            Representation representation) {
+  if (FLAG_track_fields && representation.IsSmi() && IsUninitialized()) {
+    return Smi::FromInt(0);
+  }
   if (!FLAG_track_double_fields) return this;
   if (!representation.IsDouble()) return this;
   if (IsUninitialized()) {

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 560c4db..31b2f21 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -3938,13 +3938,14 @@ 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));
@@ -3964,7 +3965,8 @@ 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());
       }
     }
@@ -3975,7 +3977,7 @@ 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());
@@ -3984,14 +3986,14 @@ 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());
@@ -4009,9 +4011,8 @@ 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()) {
@@ -4019,26 +4020,41 @@ 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.

diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 480adf8..41a331a 100644 (file)
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -2296,7 +2296,7 @@ LInstruction* LChunkBuilder::DoStoreNamedField(HStoreNamedField* instr) {
   } else if (can_be_constant) {
     val = UseRegisterOrConstant(instr->value());
   } else if (FLAG_track_fields && instr->field_representation().IsSmi()) {
-    val = UseTempRegister(instr->value());
+    val = UseRegister(instr->value());
   } else if (FLAG_track_double_fields &&
              instr->field_representation().IsDouble()) {
     val = UseRegisterAtStart(instr->value());