Experimental parser: merge to r19637

src/hydrogen-instructions.cc

 // 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 17 matching lines @@
 #include "v8.h"
 
 #include "double.h"
 #include "factory.h"
 #include "hydrogen-infer-representation.h"
 
 #if V8_TARGET_ARCH_IA32
 #include "ia32/lithium-ia32.h"
 #elif V8_TARGET_ARCH_X64
 #include "x64/lithium-x64.h"
+#elif V8_TARGET_ARCH_A64
+#include "a64/lithium-a64.h"
 #elif V8_TARGET_ARCH_ARM
 #include "arm/lithium-arm.h"
 #elif V8_TARGET_ARCH_MIPS
 #include "mips/lithium-mips.h"
 #else
 #error Unsupported target architecture.
 #endif
 
 namespace v8 {
 namespace internal {
@@ skipping 549 matching lines @@
 
 
 void HValue::PrintChangesTo(StringStream* stream) {
   GVNFlagSet changes_flags = ChangesFlags();
   if (changes_flags.IsEmpty()) return;
   stream->Add(" changes[");
   if (changes_flags == AllSideEffectsFlagSet()) {
     stream->Add("*");
   } else {
     bool add_comma = false;
-#define PRINT_DO(type)                            \
-    if (changes_flags.Contains(kChanges##type)) { \
-      if (add_comma) stream->Add(",");            \
-      add_comma = true;                           \
-      stream->Add(#type);                         \
+#define PRINT_DO(Type)                      \
+    if (changes_flags.Contains(k##Type)) {  \
+      if (add_comma) stream->Add(",");      \
+      add_comma = true;                     \
+      stream->Add(#Type);                   \
     }
     GVN_TRACKED_FLAG_LIST(PRINT_DO);
     GVN_UNTRACKED_FLAG_LIST(PRINT_DO);
 #undef PRINT_DO
   }
   stream->Add("]");
 }
 
 
 void HValue::PrintNameTo(StringStream* stream) {
@@ skipping 51 matching lines @@
 }
 
 
 void HValue::ComputeInitialRange(Zone* zone) {
   ASSERT(!HasRange());
   range_ = InferRange(zone);
   ASSERT(HasRange());
 }
 
 
+void HSourcePosition::PrintTo(FILE* out) {
+  if (IsUnknown()) {
+    PrintF(out, "<?>");
+  } else {
+    if (FLAG_hydrogen_track_positions) {
+      PrintF(out, "<%d:%d>", inlining_id(), position());
+    } else {
+      PrintF(out, "<0:%d>", raw());
+    }
+  }
+}
+
+
 void HInstruction::PrintTo(StringStream* stream) {
   PrintMnemonicTo(stream);
   PrintDataTo(stream);
   PrintRangeTo(stream);
   PrintChangesTo(stream);
   PrintTypeTo(stream);
   if (CheckFlag(HValue::kHasNoObservableSideEffects)) {
     stream->Add(" [noOSE]");
   }
+  if (CheckFlag(HValue::kIsDead)) {
+    stream->Add(" [dead]");
+  }
 }
 
 
 void HInstruction::PrintDataTo(StringStream *stream) {
   for (int i = 0; i < OperandCount(); ++i) {
     if (i > 0) stream->Add(" ");
     OperandAt(i)->PrintNameTo(stream);
   }
 }
 
@@ skipping 24 matching lines @@
   ASSERT(!next->IsBlockEntry());
   ASSERT(!IsControlInstruction());
   ASSERT(!next->block()->IsStartBlock());
   ASSERT(next->previous_ != NULL);
   HInstruction* prev = next->previous();
   prev->next_ = this;
   next->previous_ = this;
   next_ = next;
   previous_ = prev;
   SetBlock(next->block());
-  if (position() == RelocInfo::kNoPosition &&
-      next->position() != RelocInfo::kNoPosition) {
+  if (!has_position() && next->has_position()) {
     set_position(next->position());
   }
 }
 
 
 void HInstruction::InsertAfter(HInstruction* previous) {
   ASSERT(!IsLinked());
   ASSERT(!previous->IsControlInstruction());
   ASSERT(!IsControlInstruction() || previous->next_ == NULL);
   HBasicBlock* block = previous->block();
@@ skipping 16 matching lines @@
   }
 
   previous_ = previous;
   next_ = next;
   SetBlock(block);
   previous->next_ = this;
   if (next != NULL) next->previous_ = this;
   if (block->last() == previous) {
     block->set_last(this);
   }
-  if (position() == RelocInfo::kNoPosition &&
-      previous->position() != RelocInfo::kNoPosition) {
+  if (!has_position() && previous->has_position()) {
     set_position(previous->position());
   }
 }
 
 
 #ifdef DEBUG
 void HInstruction::Verify() {
   // Verify that input operands are defined before use.
   HBasicBlock* cur_block = block();
   for (int i = 0; i < OperandCount(); ++i) {
@@ skipping 321 matching lines @@
   }
   *block = NULL;
   return false;
 }
 
 
 void HCompareMap::PrintDataTo(StringStream* stream) {
   value()->PrintNameTo(stream);
   stream->Add(" (%p)", *map().handle());
   HControlInstruction::PrintDataTo(stream);
+  if (known_successor_index() == 0) {
+    stream->Add(" [true]");
+  } else if (known_successor_index() == 1) {
+    stream->Add(" [false]");
+  }
 }
 
 
 const char* HUnaryMathOperation::OpName() const {
   switch (op()) {
     case kMathFloor: return "floor";
     case kMathRound: return "round";
     case kMathAbs: return "abs";
     case kMathLog: return "log";
     case kMathExp: return "exp";
     case kMathSqrt: return "sqrt";
     case kMathPowHalf: return "pow-half";
+    case kMathClz32: return "clz32";
     default:
       UNREACHABLE();
       return NULL;
   }
 }
 
 
 Range* HUnaryMathOperation::InferRange(Zone* zone) {
   Representation r = representation();
+  if (op() == kMathClz32) return new(zone) Range(0, 32);
   if (r.IsSmiOrInteger32() && value()->HasRange()) {
     if (op() == kMathAbs) {
       int upper = value()->range()->upper();
       int lower = value()->range()->lower();
       bool spans_zero = value()->range()->CanBeZero();
       // Math.abs(kMinInt) overflows its representation, on which the
       // instruction deopts. Hence clamp it to kMaxInt.
       int abs_upper = upper == kMinInt ? kMaxInt : abs(upper);
       int abs_lower = lower == kMinInt ? kMaxInt : abs(lower);
       Range* result =
@@ skipping 253 matching lines @@
 void HChange::PrintDataTo(StringStream* stream) {
   HUnaryOperation::PrintDataTo(stream);
   stream->Add(" %s to %s", from().Mnemonic(), to().Mnemonic());
 
   if (CanTruncateToInt32()) stream->Add(" truncating-int32");
   if (CheckFlag(kBailoutOnMinusZero)) stream->Add(" -0?");
   if (CheckFlag(kAllowUndefinedAsNaN)) stream->Add(" allow-undefined-as-nan");
 }
 
 
-static HValue* SimplifiedDividendForMathFloorOfDiv(HValue* dividend) {
-  // A value with an integer representation does not need to be transformed.
-  if (dividend->representation().IsInteger32()) {
-    return dividend;
-  }
-  // A change from an integer32 can be replaced by the integer32 value.
-  if (dividend->IsChange() &&
-      HChange::cast(dividend)->from().IsInteger32()) {
-    return HChange::cast(dividend)->value();
-  }
-  return NULL;
-}
-
-
 HValue* HUnaryMathOperation::Canonicalize() {
   if (op() == kMathRound || op() == kMathFloor) {
     HValue* val = value();
     if (val->IsChange()) val = HChange::cast(val)->value();
-
-    // If the input is smi or integer32 then we replace the instruction with its
-    // input.
     if (val->representation().IsSmiOrInteger32()) {
-      if (!val->representation().Equals(representation())) {
-        HChange* result = new(block()->zone()) HChange(
-            val, representation(), false, false);
-        result->InsertBefore(this);
-        return result;
-      }
-      return val;
+      if (val->representation().Equals(representation())) return val;
+      return Prepend(new(block()->zone()) HChange(
+          val, representation(), false, false));
     }
   }
+  if (op() == kMathFloor && value()->IsDiv() && value()->UseCount() == 1) {
+    HDiv* hdiv = HDiv::cast(value());
 
-  if (op() == kMathFloor) {
-    HValue* val = value();
-    if (val->IsChange()) val = HChange::cast(val)->value();
-    if (val->IsDiv() && (val->UseCount() == 1)) {
-      HDiv* hdiv = HDiv::cast(val);
-      HValue* left = hdiv->left();
-      HValue* right = hdiv->right();
-      // Try to simplify left and right values of the division.
-      HValue* new_left = SimplifiedDividendForMathFloorOfDiv(left);
-      if (new_left == NULL &&
-          hdiv->observed_input_representation(1).IsSmiOrInteger32()) {
-        new_left = new(block()->zone()) HChange(
-            left, Representation::Integer32(), false, false);
-        HChange::cast(new_left)->InsertBefore(this);
-      }
-      HValue* new_right =
-          LChunkBuilder::SimplifiedDivisorForMathFloorOfDiv(right);
-      if (new_right == NULL &&
-#if V8_TARGET_ARCH_ARM
-          CpuFeatures::IsSupported(SUDIV) &&
-#endif
-          hdiv->observed_input_representation(2).IsSmiOrInteger32()) {
-        new_right = new(block()->zone()) HChange(
-            right, Representation::Integer32(), false, false);
-        HChange::cast(new_right)->InsertBefore(this);
-      }
+    HValue* left = hdiv->left();
+    if (left->representation().IsInteger32()) {
+      // A value with an integer representation does not need to be transformed.
+    } else if (left->IsChange() && HChange::cast(left)->from().IsInteger32()) {
+      // A change from an integer32 can be replaced by the integer32 value.
+      left = HChange::cast(left)->value();
+    } else if (hdiv->observed_input_representation(1).IsSmiOrInteger32()) {
+      left = Prepend(new(block()->zone()) HChange(
+          left, Representation::Integer32(), false, false));
+    } else {
+      return this;
+    }
 
-      // Return if left or right are not optimizable.
-      if ((new_left == NULL) || (new_right == NULL)) return this;
+    HValue* right = hdiv->right();
+    if (right->IsInteger32Constant()) {
+      right = Prepend(HConstant::cast(right)->CopyToRepresentation(
+          Representation::Integer32(), right->block()->zone()));
+    } else if (right->representation().IsInteger32()) {
+      // A value with an integer representation does not need to be transformed.
+    } else if (right->IsChange() &&
+               HChange::cast(right)->from().IsInteger32()) {
+      // A change from an integer32 can be replaced by the integer32 value.
+      right = HChange::cast(right)->value();
+    } else if (hdiv->observed_input_representation(2).IsSmiOrInteger32()) {
+      right = Prepend(new(block()->zone()) HChange(
+          right, Representation::Integer32(), false, false));
+    } else {
+      return this;
+    }
 
-      // Insert the new values in the graph.
-      if (new_left->IsInstruction() &&
-          !HInstruction::cast(new_left)->IsLinked()) {
-        HInstruction::cast(new_left)->InsertBefore(this);
-      }
-      if (new_right->IsInstruction() &&
-          !HInstruction::cast(new_right)->IsLinked()) {
-        HInstruction::cast(new_right)->InsertBefore(this);
-      }
-      HMathFloorOfDiv* instr =
-          HMathFloorOfDiv::New(block()->zone(), context(), new_left, new_right);
-      // Replace this HMathFloor instruction by the new HMathFloorOfDiv.
-      instr->InsertBefore(this);
-      ReplaceAllUsesWith(instr);
-      Kill();
-      // We know the division had no other uses than this HMathFloor. Delete it.
-      // Dead code elimination will deal with |left| and |right| if
-      // appropriate.
-      hdiv->DeleteAndReplaceWith(NULL);
-
-      // Return NULL to remove this instruction from the graph.
-      return NULL;
-    }
+    return Prepend(HMathFloorOfDiv::New(
+        block()->zone(), context(), left, right));
   }
   return this;
 }
 
 
 HValue* HCheckInstanceType::Canonicalize() {
   if (check_ == IS_STRING && value()->type().IsString()) {
     return value();
   }
 
@@ skipping 33 matching lines @@
     case IS_INTERNALIZED_STRING:
       *mask = kIsNotStringMask | kIsNotInternalizedMask;
       *tag = kInternalizedTag;
       return;
     default:
       UNREACHABLE();
   }
 }
 
 
-void HCheckMaps::HandleSideEffectDominator(GVNFlag side_effect,
+bool HCheckMaps::HandleSideEffectDominator(GVNFlag side_effect,
                                            HValue* dominator) {
-  ASSERT(side_effect == kChangesMaps);
+  ASSERT(side_effect == kMaps);
   // TODO(mstarzinger): For now we specialize on HStoreNamedField, but once
   // type information is rich enough we should generalize this to any HType
   // for which the map is known.
   if (HasNoUses() && dominator->IsStoreNamedField()) {
     HStoreNamedField* store = HStoreNamedField::cast(dominator);
-    if (!store->has_transition() || store->object() != value()) return;
+    if (!store->has_transition() || store->object() != value()) return false;
     HConstant* transition = HConstant::cast(store->transition());
     if (map_set_.Contains(transition->GetUnique())) {
       DeleteAndReplaceWith(NULL);
-      return;
+      return true;
     }
   }
+  return false;
 }
 
 
 void HCheckMaps::PrintDataTo(StringStream* stream) {
   value()->PrintNameTo(stream);
   stream->Add(" [%p", *map_set_.at(0).handle());
   for (int i = 1; i < map_set_.size(); ++i) {
     stream->Add(",%p", *map_set_.at(i).handle());
   }
   stream->Add("]%s", CanOmitMapChecks() ? "(omitted)" : "");
@@ skipping 74 matching lines @@
 
 
 Range* HChange::InferRange(Zone* zone) {
   Range* input_range = value()->range();
   if (from().IsInteger32() && !value()->CheckFlag(HInstruction::kUint32) &&
       (to().IsSmi() ||
        (to().IsTagged() &&
         input_range != NULL &&
         input_range->IsInSmiRange()))) {
     set_type(HType::Smi());
-    ClearGVNFlag(kChangesNewSpacePromotion);
+    ClearChangesFlag(kNewSpacePromotion);
   }
   Range* result = (input_range != NULL)
       ? input_range->Copy(zone)
       : HValue::InferRange(zone);
   result->set_can_be_minus_zero(!to().IsSmiOrInteger32() ||
                                 !(CheckFlag(kAllUsesTruncatingToInt32) ||
                                   CheckFlag(kAllUsesTruncatingToSmi)));
   if (to().IsSmi()) result->ClampToSmi();
   return result;
 }
 
 
 Range* HConstant::InferRange(Zone* zone) {
   if (has_int32_value_) {
     Range* result = new(zone) Range(int32_value_, int32_value_);
     result->set_can_be_minus_zero(false);
     return result;
   }
   return HValue::InferRange(zone);
 }
 
 
-int HPhi::position() const {
+HSourcePosition HPhi::position() const {
   return block()->first()->position();
 }
 
 
 Range* HPhi::InferRange(Zone* zone) {
   Representation r = representation();
   if (r.IsSmiOrInteger32()) {
     if (block()->IsLoopHeader()) {
       Range* range = r.IsSmi()
           ? new(zone) Range(Smi::kMinValue, Smi::kMaxValue)
@@ skipping 832 matching lines @@
     Heap* heap = Handle<HeapObject>::cast(handle)->GetHeap();
     is_not_in_new_space_ = !heap->InNewSpace(*handle);
   }
   if (handle->IsNumber()) {
     double n = handle->Number();
     has_int32_value_ = IsInteger32(n);
     int32_value_ = DoubleToInt32(n);
     has_smi_value_ = has_int32_value_ && Smi::IsValid(int32_value_);
     double_value_ = n;
     has_double_value_ = true;
+    // TODO(titzer): if this heap number is new space, tenure a new one.
   } else {
     is_internalized_string_ = handle->IsInternalizedString();
   }
 
   is_cell_ = !handle.is_null() &&
       (handle->IsCell() || handle->IsPropertyCell());
   Initialize(r);
 }
 
 
@@ skipping 96 matching lines @@
         }
       }
       r = Representation::Tagged();
     }
   }
   set_representation(r);
   SetFlag(kUseGVN);
 }
 
 
+bool HConstant::ImmortalImmovable() const {
+  if (has_int32_value_) {
+    return false;
+  }
+  if (has_double_value_) {
+    if (IsSpecialDouble()) {
+      return true;
+    }
+    return false;
+  }
+  if (has_external_reference_value_) {
+    return false;
+  }
+
+  ASSERT(!object_.handle().is_null());
+  Heap* heap = isolate()->heap();
+  ASSERT(!object_.IsKnownGlobal(heap->minus_zero_value()));
+  ASSERT(!object_.IsKnownGlobal(heap->nan_value()));
+  return
+#define IMMORTAL_IMMOVABLE_ROOT(name) \
+      object_.IsKnownGlobal(heap->name()) ||
+      IMMORTAL_IMMOVABLE_ROOT_LIST(IMMORTAL_IMMOVABLE_ROOT)
+#undef IMMORTAL_IMMOVABLE_ROOT
+#define INTERNALIZED_STRING(name, value) \
+      object_.IsKnownGlobal(heap->name()) ||
+      INTERNALIZED_STRING_LIST(INTERNALIZED_STRING)
+#undef INTERNALIZED_STRING
+#define STRING_TYPE(NAME, size, name, Name) \
+      object_.IsKnownGlobal(heap->name##_map()) ||
+      STRING_TYPE_LIST(STRING_TYPE)
+#undef STRING_TYPE
+      false;
+}
+
+
 bool HConstant::EmitAtUses() {
   ASSERT(IsLinked());
   if (block()->graph()->has_osr() &&
       block()->graph()->IsStandardConstant(this)) {
     // TODO(titzer): this seems like a hack that should be fixed by custom OSR.
     return true;
   }
   if (UseCount() == 0) return true;
   if (IsCell()) return false;
   if (representation().IsDouble()) return false;
@@ skipping 62 matching lines @@
   if (has_int32_value_) {
     stream->Add("%d ", int32_value_);
   } else if (has_double_value_) {
     stream->Add("%f ", FmtElm(double_value_));
   } else if (has_external_reference_value_) {
     stream->Add("%p ", reinterpret_cast<void*>(
             external_reference_value_.address()));
   } else {
     handle(Isolate::Current())->ShortPrint(stream);
   }
+  if (!is_not_in_new_space_) {
+    stream->Add("[new space] ");
+  }
 }
 
 
 void HBinaryOperation::PrintDataTo(StringStream* stream) {
   left()->PrintNameTo(stream);
   stream->Add(" ");
   right()->PrintNameTo(stream);
   if (CheckFlag(kCanOverflow)) stream->Add(" !");
   if (CheckFlag(kBailoutOnMinusZero)) stream->Add(" -0?");
 }
@@ skipping 196 matching lines @@
   }
   if (access().IsStringLength()) {
     return new(zone) Range(0, String::kMaxLength);
   }
   return HValue::InferRange(zone);
 }
 
 
 Range* HLoadKeyed::InferRange(Zone* zone) {
   switch (elements_kind()) {
-    case EXTERNAL_BYTE_ELEMENTS:
+    case EXTERNAL_INT8_ELEMENTS:
       return new(zone) Range(kMinInt8, kMaxInt8);
-    case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
-    case EXTERNAL_PIXEL_ELEMENTS:
+    case EXTERNAL_UINT8_ELEMENTS:
+    case EXTERNAL_UINT8_CLAMPED_ELEMENTS:
       return new(zone) Range(kMinUInt8, kMaxUInt8);
-    case EXTERNAL_SHORT_ELEMENTS:
+    case EXTERNAL_INT16_ELEMENTS:
       return new(zone) Range(kMinInt16, kMaxInt16);
-    case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
+    case EXTERNAL_UINT16_ELEMENTS:
       return new(zone) Range(kMinUInt16, kMaxUInt16);
     default:
       return HValue::InferRange(zone);
   }
 }
 
 
 void HCompareGeneric::PrintDataTo(StringStream* stream) {
   stream->Add(Token::Name(token()));
   stream->Add(" ");
@@ skipping 109 matching lines @@
 
 
 void HParameter::PrintDataTo(StringStream* stream) {
   stream->Add("%u", index());
 }
 
 
 void HLoadNamedField::PrintDataTo(StringStream* stream) {
   object()->PrintNameTo(stream);
   access_.PrintTo(stream);
+
+  if (HasDependency()) {
+    stream->Add(" ");
+    dependency()->PrintNameTo(stream);
+  }
 }
 
 
 HCheckMaps* HCheckMaps::New(Zone* zone,
                             HValue* context,
                             HValue* value,
                             Handle<Map> map,
                             CompilationInfo* info,
                             HValue* typecheck) {
   HCheckMaps* check_map = new(zone) HCheckMaps(value, zone, typecheck);
@@ skipping 130 matching lines @@
                                 names_cache->map());
         HInstruction* index = HLoadKeyed::New(
             block()->graph()->zone(),
             block()->graph()->GetInvalidContext(),
             index_cache,
             key_load->key(),
             key_load->key(),
             key_load->elements_kind());
         map_check->InsertBefore(this);
         index->InsertBefore(this);
-        HLoadFieldByIndex* load = new(block()->zone()) HLoadFieldByIndex(
-            object(), index);
-        load->InsertBefore(this);
-        return load;
+        return Prepend(new(block()->zone()) HLoadFieldByIndex(
+            object(), index));
       }
     }
   }
 
   return this;
 }
 
 
 void HStoreNamedGeneric::PrintDataTo(StringStream* stream) {
   object()->PrintNameTo(stream);
@@ skipping 143 matching lines @@
   // If any of the actual input representation is more general than what we
   // have so far but not Tagged, use that representation instead.
   Representation input_rep = value()->representation();
   if (!input_rep.IsTagged()) {
     rep = rep.generalize(input_rep);
   }
   return rep;
 }
 
 
-void HAllocate::HandleSideEffectDominator(GVNFlag side_effect,
+bool HAllocate::HandleSideEffectDominator(GVNFlag side_effect,
                                           HValue* dominator) {
-  ASSERT(side_effect == kChangesNewSpacePromotion);
+  ASSERT(side_effect == kNewSpacePromotion);
   Zone* zone = block()->zone();
-  if (!FLAG_use_allocation_folding) return;
+  if (!FLAG_use_allocation_folding) return false;
 
   // Try to fold allocations together with their dominating allocations.
   if (!dominator->IsAllocate()) {
     if (FLAG_trace_allocation_folding) {
       PrintF("#%d (%s) cannot fold into #%d (%s)\n",
           id(), Mnemonic(), dominator->id(), dominator->Mnemonic());
     }
-    return;
+    return false;
+  }
+
+  // Check whether we are folding within the same block for local folding.
+  if (FLAG_use_local_allocation_folding && dominator->block() != block()) {
+    if (FLAG_trace_allocation_folding) {
+      PrintF("#%d (%s) cannot fold into #%d (%s), crosses basic blocks\n",
+          id(), Mnemonic(), dominator->id(), dominator->Mnemonic());
+    }
+    return false;
   }
 
   HAllocate* dominator_allocate = HAllocate::cast(dominator);
   HValue* dominator_size = dominator_allocate->size();
   HValue* current_size = size();
 
   // TODO(hpayer): Add support for non-constant allocation in dominator.
   if (!current_size->IsInteger32Constant() ||
       !dominator_size->IsInteger32Constant()) {
     if (FLAG_trace_allocation_folding) {
       PrintF("#%d (%s) cannot fold into #%d (%s), dynamic allocation size\n",
           id(), Mnemonic(), dominator->id(), dominator->Mnemonic());
     }
-    return;
+    return false;
   }
 
   dominator_allocate = GetFoldableDominator(dominator_allocate);
   if (dominator_allocate == NULL) {
-    return;
+    return false;
   }
 
   ASSERT((IsNewSpaceAllocation() &&
          dominator_allocate->IsNewSpaceAllocation()) ||
          (IsOldDataSpaceAllocation() &&
          dominator_allocate->IsOldDataSpaceAllocation()) ||
          (IsOldPointerSpaceAllocation() &&
          dominator_allocate->IsOldPointerSpaceAllocation()));
 
   // First update the size of the dominator allocate instruction.
   dominator_size = dominator_allocate->size();
   int32_t original_object_size =
       HConstant::cast(dominator_size)->GetInteger32Constant();
   int32_t dominator_size_constant = original_object_size;
   int32_t current_size_constant =
       HConstant::cast(current_size)->GetInteger32Constant();
   int32_t new_dominator_size = dominator_size_constant + current_size_constant;
 
   if (MustAllocateDoubleAligned()) {
     if (!dominator_allocate->MustAllocateDoubleAligned()) {
       dominator_allocate->MakeDoubleAligned();
     }
     if ((dominator_size_constant & kDoubleAlignmentMask) != 0) {
       dominator_size_constant += kDoubleSize / 2;
       new_dominator_size += kDoubleSize / 2;
     }
   }
 
-  if (new_dominator_size > isolate()->heap()->MaxRegularSpaceAllocationSize()) {
+  // Since we clear the first word after folded memory, we cannot use the
+  // whole Page::kMaxRegularHeapObjectSize memory.
+  if (new_dominator_size > Page::kMaxRegularHeapObjectSize - kPointerSize) {
     if (FLAG_trace_allocation_folding) {
       PrintF("#%d (%s) cannot fold into #%d (%s) due to size: %d\n",
           id(), Mnemonic(), dominator_allocate->id(),
           dominator_allocate->Mnemonic(), new_dominator_size);
     }
-    return;
+    return false;
   }
 
   HInstruction* new_dominator_size_constant = HConstant::CreateAndInsertBefore(
       zone,
       context(),
       new_dominator_size,
       Representation::None(),
       dominator_allocate);
   dominator_allocate->UpdateSize(new_dominator_size_constant);
 
@@ skipping 27 matching lines @@
                                  dominator_allocate,
                                  inner_offset,
                                  type());
   dominated_allocate_instr->InsertBefore(this);
   DeleteAndReplaceWith(dominated_allocate_instr);
   if (FLAG_trace_allocation_folding) {
     PrintF("#%d (%s) folded into #%d (%s)\n",
         id(), Mnemonic(), dominator_allocate->id(),
         dominator_allocate->Mnemonic());
   }
+  return true;
 }
 
 
 HAllocate* HAllocate::GetFoldableDominator(HAllocate* dominator) {
   if (!IsFoldable(dominator)) {
     // We cannot hoist old space allocations over new space allocations.
     if (IsNewSpaceAllocation() || dominator->IsNewSpaceAllocation()) {
       if (FLAG_trace_allocation_folding) {
         PrintF("#%d (%s) cannot fold into #%d (%s), new space hoisting\n",
             id(), Mnemonic(), dominator->id(), dominator->Mnemonic());
@@ skipping 89 matching lines @@
   store_map->SetFlag(HValue::kHasNoObservableSideEffects);
   store_map->InsertAfter(filler_map);
 
   // We must explicitly force Smi representation here because on x64 we
   // would otherwise automatically choose int32, but the actual store
   // requires a Smi-tagged value.
   HConstant* filler_size = HConstant::CreateAndInsertAfter(
       zone, context(), free_space_size, Representation::Smi(), store_map);
   // Must force Smi representation for x64 (see comment above).
   HObjectAccess access =
-      HObjectAccess::ForJSObjectOffset(FreeSpace::kSizeOffset,
-          Representation::Smi());
+      HObjectAccess::ForMapAndOffset(isolate()->factory()->free_space_map(),
+                                     FreeSpace::kSizeOffset,
+                                     Representation::Smi());
   HStoreNamedField* store_size = HStoreNamedField::New(zone, context(),
       free_space_instr, access, filler_size);
   store_size->SetFlag(HValue::kHasNoObservableSideEffects);
   store_size->InsertAfter(filler_size);
   filler_free_space_size_ = store_size;
 }
 
 
 void HAllocate::ClearNextMapWord(int offset) {
   if (MustClearNextMapWord()) {
     Zone* zone = block()->zone();
-    HObjectAccess access = HObjectAccess::ForJSObjectOffset(offset);
+    HObjectAccess access =
+        HObjectAccess::ForObservableJSObjectOffset(offset);
     HStoreNamedField* clear_next_map =
         HStoreNamedField::New(zone, context(), this, access,
             block()->graph()->GetConstant0());
     clear_next_map->ClearAllSideEffects();
     clear_next_map->InsertAfter(this);
   }
 }
 
 
 void HAllocate::PrintDataTo(StringStream* stream) {
@@ skipping 231 matching lines @@
           return H_CONSTANT_DOUBLE((d > 0.0) ? d : 0.0);
         case kMathLog:
         case kMathSqrt:
           return H_CONSTANT_DOUBLE((d > 0.0) ? d : OS::nan_value());
         case kMathPowHalf:
         case kMathAbs:
           return H_CONSTANT_DOUBLE((d > 0.0) ? d : -d);
         case kMathRound:
         case kMathFloor:
           return H_CONSTANT_DOUBLE(d);
+        case kMathClz32:
+          return H_CONSTANT_INT(32);
         default:
           UNREACHABLE();
           break;
       }
     }
     switch (op) {
       case kMathExp:
         return H_CONSTANT_DOUBLE(fast_exp(d));
       case kMathLog:
         return H_CONSTANT_DOUBLE(std::log(d));
       case kMathSqrt:
         return H_CONSTANT_DOUBLE(fast_sqrt(d));
       case kMathPowHalf:
         return H_CONSTANT_DOUBLE(power_double_double(d, 0.5));
       case kMathAbs:
         return H_CONSTANT_DOUBLE((d >= 0.0) ? d + 0.0 : -d);
       case kMathRound:
         // -0.5 .. -0.0 round to -0.0.
         if ((d >= -0.5 && Double(d).Sign() < 0)) return H_CONSTANT_DOUBLE(-0.0);
         // Doubles are represented as Significant * 2 ^ Exponent. If the
         // Exponent is not negative, the double value is already an integer.
         if (Double(d).Exponent() >= 0) return H_CONSTANT_DOUBLE(d);
         return H_CONSTANT_DOUBLE(std::floor(d + 0.5));
       case kMathFloor:
         return H_CONSTANT_DOUBLE(std::floor(d));
+      case kMathClz32: {
+        uint32_t i = DoubleToUint32(d);
+        return H_CONSTANT_INT(
+            (i == 0) ? 32 : CompilerIntrinsics::CountLeadingZeros(i));
+      }
       default:
         UNREACHABLE();
         break;
     }
   } while (false);
   return new(zone) HUnaryMathOperation(context, value, op);
 }
 
 
 HInstruction* HPower::New(Zone* zone,
@@ skipping 330 matching lines @@
 
 
 HObjectAccess HObjectAccess::ForFixedArrayHeader(int offset) {
   ASSERT(offset >= 0);
   ASSERT(offset < FixedArray::kHeaderSize);
   if (offset == FixedArray::kLengthOffset) return ForFixedArrayLength();
   return HObjectAccess(kInobject, offset);
 }
 
 
-HObjectAccess HObjectAccess::ForJSObjectOffset(int offset,
+HObjectAccess HObjectAccess::ForMapAndOffset(Handle<Map> map, int offset,
     Representation representation) {
   ASSERT(offset >= 0);
   Portion portion = kInobject;
 
   if (offset == JSObject::kElementsOffset) {
     portion = kElementsPointer;
   } else if (offset == JSObject::kMapOffset) {
     portion = kMaps;
   }
-  return HObjectAccess(portion, offset, representation);
+  bool existing_inobject_property = true;
+  if (!map.is_null()) {
+    existing_inobject_property = (offset <
+        map->instance_size() - map->unused_property_fields() * kPointerSize);
+  }
+  return HObjectAccess(portion, offset, representation, Handle<String>::null(),
+                       false, existing_inobject_property);
 }
 
 
 HObjectAccess HObjectAccess::ForAllocationSiteOffset(int offset) {
   switch (offset) {
     case AllocationSite::kTransitionInfoOffset:
       return HObjectAccess(kInobject, offset, Representation::Tagged());
     case AllocationSite::kNestedSiteOffset:
       return HObjectAccess(kInobject, offset, Representation::Tagged());
     case AllocationSite::kPretenureDataOffset:
@@ skipping 31 matching lines @@
   } else if (offset == JSObject::kMapOffset) {
     portion = kMaps;
   }
   return HObjectAccess(portion, offset);
 }
 
 
 HObjectAccess HObjectAccess::ForBackingStoreOffset(int offset,
     Representation representation) {
   ASSERT(offset >= 0);
-  return HObjectAccess(kBackingStore, offset, representation);
+  return HObjectAccess(kBackingStore, offset, representation,
+                       Handle<String>::null(), false, false);
 }
 
 
 HObjectAccess HObjectAccess::ForField(Handle<Map> map,
-    LookupResult *lookup, Handle<String> name) {
-  ASSERT(lookup->IsField() || lookup->IsTransitionToField(*map));
+                                      LookupResult* lookup,
+                                      Handle<String> name) {
+  ASSERT(lookup->IsField() || lookup->IsTransitionToField());
   int index;
   Representation representation;
   if (lookup->IsField()) {
     index = lookup->GetLocalFieldIndexFromMap(*map);
     representation = lookup->representation();
   } else {
-    Map* transition = lookup->GetTransitionMapFromMap(*map);
+    Map* transition = lookup->GetTransitionTarget();
     int descriptor = transition->LastAdded();
     index = transition->instance_descriptors()->GetFieldIndex(descriptor) -
         map->inobject_properties();
     PropertyDetails details =
         transition->instance_descriptors()->GetDetails(descriptor);
     representation = details.representation();
   }
   if (index < 0) {
     // Negative property indices are in-object properties, indexed
     // from the end of the fixed part of the object.
     int offset = (index * kPointerSize) + map->instance_size();
-    return HObjectAccess(kInobject, offset, representation);
+    return HObjectAccess(kInobject, offset, representation, name, false, true);
   } else {
     // Non-negative property indices are in the properties array.
     int offset = (index * kPointerSize) + FixedArray::kHeaderSize;
-    return HObjectAccess(kBackingStore, offset, representation, name);
+    return HObjectAccess(kBackingStore, offset, representation, name,
+                         false, false);
   }
 }
 
 
 HObjectAccess HObjectAccess::ForCellPayload(Isolate* isolate) {
   return HObjectAccess(
       kInobject, Cell::kValueOffset, Representation::Tagged(),
       Handle<String>(isolate->heap()->cell_value_string()));
 }
 
 
-void HObjectAccess::SetGVNFlags(HValue *instr, bool is_store) {
+void HObjectAccess::SetGVNFlags(HValue *instr, PropertyAccessType access_type) {
   // set the appropriate GVN flags for a given load or store instruction
-  if (is_store) {
+  if (access_type == STORE) {
     // track dominating allocations in order to eliminate write barriers
-    instr->SetGVNFlag(kDependsOnNewSpacePromotion);
+    instr->SetDependsOnFlag(::v8::internal::kNewSpacePromotion);
     instr->SetFlag(HValue::kTrackSideEffectDominators);
   } else {
     // try to GVN loads, but don't hoist above map changes
     instr->SetFlag(HValue::kUseGVN);
-    instr->SetGVNFlag(kDependsOnMaps);
+    instr->SetDependsOnFlag(::v8::internal::kMaps);
   }
 
   switch (portion()) {
     case kArrayLengths:
-      instr->SetGVNFlag(is_store
-          ? kChangesArrayLengths : kDependsOnArrayLengths);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kArrayLengths);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kArrayLengths);
+      }
       break;
     case kStringLengths:
-      instr->SetGVNFlag(is_store
-          ? kChangesStringLengths : kDependsOnStringLengths);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kStringLengths);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kStringLengths);
+      }
       break;
     case kInobject:
-      instr->SetGVNFlag(is_store
-          ? kChangesInobjectFields : kDependsOnInobjectFields);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kInobjectFields);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kInobjectFields);
+      }
       break;
     case kDouble:
-      instr->SetGVNFlag(is_store
-          ? kChangesDoubleFields : kDependsOnDoubleFields);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kDoubleFields);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kDoubleFields);
+      }
       break;
     case kBackingStore:
-      instr->SetGVNFlag(is_store
-          ? kChangesBackingStoreFields : kDependsOnBackingStoreFields);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kBackingStoreFields);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kBackingStoreFields);
+      }
       break;
     case kElementsPointer:
-      instr->SetGVNFlag(is_store
-          ? kChangesElementsPointer : kDependsOnElementsPointer);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kElementsPointer);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kElementsPointer);
+      }
       break;
     case kMaps:
-      instr->SetGVNFlag(is_store
-          ? kChangesMaps : kDependsOnMaps);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kMaps);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kMaps);
+      }
       break;
     case kExternalMemory:
-      instr->SetGVNFlag(is_store
-          ? kChangesExternalMemory : kDependsOnExternalMemory);
+      if (access_type == STORE) {
+        instr->SetChangesFlag(::v8::internal::kExternalMemory);
+      } else {
+        instr->SetDependsOnFlag(::v8::internal::kExternalMemory);
+      }
       break;
   }
 }
 
 
-void HObjectAccess::PrintTo(StringStream* stream) {
+void HObjectAccess::PrintTo(StringStream* stream) const {
   stream->Add(".");
 
   switch (portion()) {
     case kArrayLengths:
     case kStringLengths:
       stream->Add("%length");
       break;
     case kElementsPointer:
       stream->Add("%elements");
       break;
@@ skipping 15 matching lines @@
       break;
     case kExternalMemory:
       stream->Add("[external-memory]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal