Parallel recompilation: fewer handle dereferences and tighter checks.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 823fea942ecf5ed8e8294e7ebd02e4320efef06c..becc7f9c28e79d57fa137a17eb608ffd7cd5edc4 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -386,7 +386,7 @@ class HType {
     return HType(static_cast<Type>(type_ & other.type_));
   }
 
-  bool Equals(const HType& other) {
+  bool Equals(const HType& other) const {
     return type_ == other.type_;
   }
 
@@ -394,66 +394,66 @@ class HType {
     return Combine(other).Equals(other);
   }
 
-  bool IsTagged() {
+  bool IsTagged() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kTagged) == kTagged);
   }
 
-  bool IsTaggedPrimitive() {
+  bool IsTaggedPrimitive() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kTaggedPrimitive) == kTaggedPrimitive);
   }
 
-  bool IsTaggedNumber() {
+  bool IsTaggedNumber() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kTaggedNumber) == kTaggedNumber);
   }
 
-  bool IsSmi() {
+  bool IsSmi() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kSmi) == kSmi);
   }
 
-  bool IsHeapNumber() {
+  bool IsHeapNumber() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kHeapNumber) == kHeapNumber);
   }
 
-  bool IsString() {
+  bool IsString() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kString) == kString);
   }
 
-  bool IsBoolean() {
+  bool IsBoolean() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kBoolean) == kBoolean);
   }
 
-  bool IsNonPrimitive() {
+  bool IsNonPrimitive() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kNonPrimitive) == kNonPrimitive);
   }
 
-  bool IsJSArray() {
+  bool IsJSArray() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kJSArray) == kJSArray);
   }
 
-  bool IsJSObject() {
+  bool IsJSObject() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kJSObject) == kJSObject);
   }
 
-  bool IsUninitialized() {
+  bool IsUninitialized() const {
     return type_ == kUninitialized;
   }
 
-  bool IsHeapObject() {
+  bool IsHeapObject() const {
     ASSERT(type_ != kUninitialized);
     return IsHeapNumber() || IsString() || IsNonPrimitive();
   }
 
-  static HType TypeFromValue(Isolate* isolate, Handle<Object> value);
+  static HType TypeFromValue(Handle<Object> value);
 
   const char* ToString();
 
@@ -2792,7 +2792,10 @@ class HCheckPrototypeMaps: public HTemplateInstruction<0> {
   virtual intptr_t Hashcode() {
     ASSERT_ALLOCATION_DISABLED;
     // Dereferencing to use the object's raw address for hashing is safe.
-    AllowHandleDereference allow_handle_deref(isolate());
+    HandleDereferenceGuard allow_handle_deref(isolate(),
+                                              HandleDereferenceGuard::ALLOW);
+    SLOW_ASSERT(Heap::RelocationLock::IsLocked(isolate()->heap()) ||
+                !isolate()->optimizing_compiler_thread()->IsOptimizerThread());
     intptr_t hash = 0;
     for (int i = 0; i < prototypes_.length(); i++) {
       hash = 17 * hash + reinterpret_cast<intptr_t>(*prototypes_[i]);
@@ -3070,8 +3073,17 @@ class HArgumentsObject: public HTemplateInstruction<0> {
 class HConstant: public HTemplateInstruction<0> {
  public:
   HConstant(Handle<Object> handle, Representation r);
-  HConstant(int32_t value, Representation r);
-  HConstant(double value, Representation r);
+  HConstant(int32_t value,
+            Representation r,
+            Handle<Object> optional_handle = Handle<Object>::null());
+  HConstant(double value,
+            Representation r,
+            Handle<Object> optional_handle = Handle<Object>::null());
+  HConstant(Handle<Object> handle,
+            Representation r,
+            HType type,
+            bool is_internalized_string,
+            bool boolean_value);
 
   Handle<Object> handle() {
     if (handle_.is_null()) {
@@ -3099,8 +3111,9 @@ class HConstant: public HTemplateInstruction<0> {
     Heap* heap = isolate()->heap();
     // We should have handled minus_zero_value and nan_value in the
     // has_double_value_ clause above.
-    // Dereferencing is safe to compare against singletons.
-    AllowHandleDereference allow_handle_deref(isolate());
+    // Dereferencing is safe to compare against immovable singletons.
+    HandleDereferenceGuard allow_handle_deref(isolate(),
+                                              HandleDereferenceGuard::ALLOW);
     ASSERT(*handle_ != heap->minus_zero_value());
     ASSERT(*handle_ != heap->nan_value());
     return *handle_ == heap->undefined_value() ||
@@ -3149,14 +3162,17 @@ class HConstant: public HTemplateInstruction<0> {
   bool HasStringValue() const {
     if (has_double_value_ || has_int32_value_) return false;
     ASSERT(!handle_.is_null());
-    return handle_->IsString();
+    return type_from_value_.IsString();
   }
   Handle<String> StringValue() const {
     ASSERT(HasStringValue());
     return Handle<String>::cast(handle_);
   }
+  bool HasInternalizedStringValue() const {
+    return HasStringValue() && is_internalized_string_;
+  }
 
-  bool ToBoolean();
+  bool BooleanValue() const { return boolean_value_; }
 
   bool IsUint32() {
     return HasInteger32Value() && (Integer32Value() >= 0);
@@ -3173,7 +3189,10 @@ class HConstant: public HTemplateInstruction<0> {
     } else {
       ASSERT(!handle_.is_null());
       // Dereferencing to use the object's raw address for hashing is safe.
-      AllowHandleDereference allow_handle_deref(isolate());
+      HandleDereferenceGuard allow_handle_deref(isolate(),
+                                                HandleDereferenceGuard::ALLOW);
+      SLOW_ASSERT(Heap::RelocationLock::IsLocked(isolate()->heap()) ||
+                 !isolate()->optimizing_compiler_thread()->IsOptimizerThread());
       hash = reinterpret_cast<intptr_t>(*handle_);
     }
 
@@ -3223,8 +3242,11 @@ class HConstant: public HTemplateInstruction<0> {
   // not the converse.
   bool has_int32_value_ : 1;
   bool has_double_value_ : 1;
+  bool is_internalized_string_ : 1;  // TODO(yangguo): make this part of HType.
+  bool boolean_value_ : 1;
   int32_t int32_value_;
   double double_value_;
+  HType type_from_value_;
 };
 
 
@@ -4526,7 +4548,10 @@ class HLoadGlobalCell: public HTemplateInstruction<0> {
   virtual intptr_t Hashcode() {
     ASSERT_ALLOCATION_DISABLED;
     // Dereferencing to use the object's raw address for hashing is safe.
-    AllowHandleDereference allow_handle_deref(isolate());
+    HandleDereferenceGuard allow_handle_deref(isolate(),
+                                              HandleDereferenceGuard::ALLOW);
+    SLOW_ASSERT(Heap::RelocationLock::IsLocked(isolate()->heap()) ||
+               !isolate()->optimizing_compiler_thread()->IsOptimizerThread());
     return reinterpret_cast<intptr_t>(*cell_);
   }