Reland "In-object double fields unboxing (for 64-bit only)."

src/arm64/lithium-codegen-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/arm64/lithium-codegen-arm64.h"
 #include "src/arm64/lithium-gap-resolver-arm64.h"
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 3642 matching lines @@
   int offset = access.offset();
   Register object = ToRegister(instr->object());
 
   if (access.IsExternalMemory()) {
     Register result = ToRegister(instr->result());
     __ Load(result, MemOperand(object, offset), access.representation());
     return;
   }
 
   if (instr->hydrogen()->representation().IsDouble()) {
+    DCHECK(access.IsInobject());
     FPRegister result = ToDoubleRegister(instr->result());
     __ Ldr(result, FieldMemOperand(object, offset));
     return;
   }
 
   Register result = ToRegister(instr->result());
   Register source;
   if (access.IsInobject()) {
     source = object;
   } else {
@@ skipping 1670 matching lines @@
   if (access.IsExternalMemory()) {
     DCHECK(!instr->hydrogen()->has_transition());
     DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
     Register value = ToRegister(instr->value());
     __ Store(value, MemOperand(object, offset), representation);
     return;
   }
 
   __ AssertNotSmi(object);
 
-  if (representation.IsDouble()) {
+  if (!FLAG_unbox_double_fields && representation.IsDouble()) {
     DCHECK(access.IsInobject());
     DCHECK(!instr->hydrogen()->has_transition());
     DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
     FPRegister value = ToDoubleRegister(instr->value());
     __ Str(value, FieldMemOperand(object, offset));
     return;
   }
 
-  Register value = ToRegister(instr->value());
-
   DCHECK(!representation.IsSmi() ||
          !instr->value()->IsConstantOperand() ||
          IsInteger32Constant(LConstantOperand::cast(instr->value())));
 
   if (instr->hydrogen()->has_transition()) {
     Handle<Map> transition = instr->hydrogen()->transition_map();
     AddDeprecationDependency(transition);
     // Store the new map value.
     Register new_map_value = ToRegister(instr->temp0());
     __ Mov(new_map_value, Operand(transition));
@@ skipping 11 matching lines @@
   // Do the store.
   Register destination;
   if (access.IsInobject()) {
     destination = object;
   } else {
     Register temp0 = ToRegister(instr->temp0());
     __ Ldr(temp0, FieldMemOperand(object, JSObject::kPropertiesOffset));
     destination = temp0;
   }
 
-  if (representation.IsSmi() &&
-     instr->hydrogen()->value()->representation().IsInteger32()) {
+  if (FLAG_unbox_double_fields && representation.IsDouble()) {
+    DCHECK(access.IsInobject());
+    FPRegister value = ToDoubleRegister(instr->value());
+    __ Str(value, FieldMemOperand(object, offset));
+  } else if (representation.IsSmi() &&
+             instr->hydrogen()->value()->representation().IsInteger32()) {
     DCHECK(instr->hydrogen()->store_mode() == STORE_TO_INITIALIZED_ENTRY);
 #ifdef DEBUG
     Register temp0 = ToRegister(instr->temp0());
     __ Ldr(temp0, FieldMemOperand(destination, offset));
     __ AssertSmi(temp0);
     // If destination aliased temp0, restore it to the address calculated
     // earlier.
     if (destination.Is(temp0)) {
       DCHECK(!access.IsInobject());
       __ Ldr(destination, FieldMemOperand(object, JSObject::kPropertiesOffset));
     }
 #endif
     STATIC_ASSERT(static_cast<unsigned>(kSmiValueSize) == kWRegSizeInBits);
     STATIC_ASSERT(kSmiTag == 0);
+    Register value = ToRegister(instr->value());
     __ Store(value, UntagSmiFieldMemOperand(destination, offset),
              Representation::Integer32());
   } else {
+    Register value = ToRegister(instr->value());
     __ Store(value, FieldMemOperand(destination, offset), representation);
   }
   if (instr->hydrogen()->NeedsWriteBarrier()) {
+    Register value = ToRegister(instr->value());
     __ RecordWriteField(destination,
                         offset,
                         value,                        // Clobbered.
                         ToRegister(instr->temp1()),   // Clobbered.
                         GetLinkRegisterState(),
                         kSaveFPRegs,
                         EMIT_REMEMBERED_SET,
                         instr->hydrogen()->SmiCheckForWriteBarrier(),
                         instr->hydrogen()->PointersToHereCheckForValue());
   }
@@ skipping 610 matching lines @@
   Handle<ScopeInfo> scope_info = instr->scope_info();
   __ Push(scope_info);
   __ Push(ToRegister(instr->function()));
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 
 } }  // namespace v8::internal