- Tighten assertions in the X64 assembler related to object pool usage.

runtime/vm/intrinsifier_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 99 matching lines @@
   __ movq(RDI, Address(RSP, kArrayLengthOffset));  // Array Length.
   __ StoreIntoObjectNoBarrier(RAX,
                               FieldAddress(RAX, Array::length_offset()),
                               RDI);
 
   // Initialize all array elements to raw_null.
   // RAX: new object start as a tagged pointer.
   // RCX: new object end address.
   // RDI: iterator which initially points to the start of the variable
   // data area to be initialized.
-  __ LoadObject(R12, Object::Handle(), PP);
+  __ LoadObject(R12, Object::null_object(), PP);
   __ leaq(RDI, FieldAddress(RAX, sizeof(RawArray)));
   Label done;
   Label init_loop;
   __ Bind(&init_loop);
   __ cmpq(RDI, RCX);
   __ j(ABOVE_EQUAL, &done, Assembler::kNearJump);
   __ movq(Address(RDI, 0), R12);
   __ addq(RDI, Immediate(kWordSize));
   __ jmp(&init_loop, Assembler::kNearJump);
   __ Bind(&done);
@@ skipping 253 matching lines @@
   __ j(EQUAL, &fall_through);  // Must grow data.
   const Immediate& value_one =
       Immediate(reinterpret_cast<int64_t>(Smi::New(1)));
   // len = len + 1;
   __ addq(FieldAddress(RAX, GrowableObjectArray::length_offset()), value_one);
   __ movq(RAX, Address(RSP, + 1 * kWordSize));  // Value
   ASSERT(kSmiTagShift == 1);
   __ StoreIntoObject(RDX,
                      FieldAddress(RDX, RCX, TIMES_4, Array::data_offset()),
                      RAX);
-  __ LoadObject(RAX, Object::Handle(), PP);
+  __ LoadObject(RAX, Object::null_object(), PP);
   __ ret();
   __ Bind(&fall_through);
 }
 
 
 #define TYPED_ARRAY_ALLOCATION(type_name, cid, max_len, scale_factor)          \
   Label fall_through;                                                          \
   const intptr_t kArrayLengthStackOffset = 1 * kWordSize;                      \
   __ movq(RDI, Address(RSP, kArrayLengthStackOffset));  /* Array length. */    \
   /* Check that length is a positive Smi. */                                   \
@@ skipping 1244 matching lines @@
 
   __ Bind(&fall_through);
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64