Parallel recompilation: fewer handle dereferences and tighter checks.

src/hydrogen-instructions.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 376 matching lines @@
   }
 
   bool Equals(const HType& other) {
     return type_ == other.type_;
   }
 
   bool IsSubtypeOf(const HType& other) {
     return Combine(other).Equals(other);
   }
 
-  bool IsTagged() {
+  bool IsTagged() const {
     ASSERT(type_ != kUninitialized);
     return ((type_ & kTagged) == kTagged);
   }
 
   bool IsTaggedPrimitive() {

[Jakob Kummerow, 2013/03/13 15:50:31]

forgot to mark this const too?

[Yang, 2013/03/13 17:00:15]

Done.

     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();
 
  private:
   enum Type {
     kTagged = 0x1,           // 0000 0000 0000 0001
     kTaggedPrimitive = 0x5,  // 0000 0000 0000 0101
     kTaggedNumber = 0xd,     // 0000 0000 0000 1101
     kSmi = 0x1d,             // 0000 0000 0001 1101
     kHeapNumber = 0x2d,      // 0000 0000 0010 1101
@@ skipping 2318 matching lines @@
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::None();
   }
 
   virtual void PrintDataTo(StringStream* stream);
 
   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]);
       hash = 17 * hash + reinterpret_cast<intptr_t>(*maps_[i]);
     }
     return hash;
   }
 
   bool CanOmitPrototypeChecks() {
     for (int i = 0; i < maps()->length(); i++) {
@@ skipping 257 matching lines @@
   DECLARE_CONCRETE_INSTRUCTION(ArgumentsObject)
 
  private:
   virtual bool IsDeletable() const { return true; }
 };
 
 
 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()) {
       handle_ = FACTORY->NewNumber(double_value_, TENURED);
     }
     ASSERT(has_int32_value_ || !handle_->IsSmi());
     return handle_;
   }
 
   bool InOldSpace() const { return !HEAP->InNewSpace(*handle_); }
 
   bool ImmortalImmovable() const {
     if (has_int32_value_) {
       return false;
     }
     if (has_double_value_) {
       if (BitCast<int64_t>(double_value_) == BitCast<int64_t>(-0.0) ||
           isnan(double_value_)) {
         return true;
       }
       return false;
     }
 
     ASSERT(!handle_.is_null());
     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() ||
            *handle_ == heap->null_value() ||
            *handle_ == heap->true_value() ||
            *handle_ == heap->false_value() ||
            *handle_ == heap->the_hole_value() ||
            *handle_ == heap->empty_string();
   }
 
@@ skipping 28 matching lines @@
   int32_t NumberValueAsInteger32() const {
     ASSERT(HasNumberValue());
     // Irrespective of whether a numeric HConstant can be safely
     // represented as an int32, we store the (in some cases lossy)
     // representation of the number in int32_value_.
     return int32_value_;
   }
   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() { return boolean_value_; }

[Jakob Kummerow, 2013/03/13 15:50:31]

nit: boolean_value()

[Yang, 2013/03/13 17:00:15]

I thought camel case was more appropriate since StringValue() and DoubleValue()
are also simple getters.

 
   bool IsUint32() {
     return HasInteger32Value() && (Integer32Value() >= 0);
   }
 
   virtual intptr_t Hashcode() {
     ASSERT_ALLOCATION_DISABLED;
     intptr_t hash;
 
     if (has_int32_value_) {
       hash = static_cast<intptr_t>(int32_value_);
     } else if (has_double_value_) {
       hash = static_cast<intptr_t>(BitCast<int64_t>(double_value_));
     } 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_);
     }
 
     return hash;
   }
 
 #ifdef DEBUG
   virtual void Verify() { }
 #endif
 
@@ skipping 27 matching lines @@
   // HeapObject the constant originated from or is null.  If the
   // constant is non-numeric, handle_ always points to a valid
   // constant HeapObject.
   Handle<Object> handle_;
 
   // We store the HConstant in the most specific form safely possible.
   // The two flags, has_int32_value_ and has_double_value_ tell us if
   // int32_value_ and double_value_ hold valid, safe representations
   // of the constant.  has_int32_value_ implies has_double_value_ but
   // not the converse.
   bool has_int32_value_ : 1;

[Jakob Kummerow, 2013/03/13 15:50:31]

I would be nice to replace this with type_from_value_, but I realize that HType
currently can't express the concepts "int32" and "double". :-(

[Yang, 2013/03/13 17:00:15]

Done.

   bool has_double_value_ : 1;
   int32_t int32_value_;
   double double_value_;
+  HType type_from_value_;
+  bool is_internalized_string_;  // TODO(yangguo) make this part of HType

[Jakob Kummerow, 2013/03/13 15:50:31]

Please move this up to the other has_$FOO_value_ properties.

[Yang, 2013/03/13 17:00:15]

Done.

+  bool boolean_value_;

[Jakob Kummerow, 2013/03/13 15:50:31]

Please move this up to the other $FOO_value_ properties.

In fact, please put all four bools next to each other, and restrict them all to
using a single bit, so we can save some memory here.

[Yang, 2013/03/13 17:00:15]

Done.

+  intptr_t handle_hash_;
 };
 
 
 class HBinaryOperation: public HTemplateInstruction<3> {
  public:
   HBinaryOperation(HValue* context, HValue* left, HValue* right)
       : observed_output_representation_(Representation::None()) {
     ASSERT(left != NULL && right != NULL);
     SetOperandAt(0, context);
     SetOperandAt(1, left);
@@ skipping 1281 matching lines @@
   }
 
   Handle<JSGlobalPropertyCell> cell() const { return cell_; }
   bool RequiresHoleCheck() const;
 
   virtual void PrintDataTo(StringStream* stream);
 
   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_);
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::None();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(LoadGlobalCell)
 
  protected:
@@ skipping 1658 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_