Intrinsify fixed and growable array allocation on x64.

runtime/vm/stub_code_x64.cc

 // Copyright (c) 2012, 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"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/assembler_macros.h"
 #include "vm/code_generator.h"
@@ skipping 591 matching lines @@
 //   RBX : array element type (either NULL or an instantiated type).
 // NOTE: R10 cannot be clobbered here as the caller relies on it being saved.
 // The newly allocated object is returned in RAX.
 void StubCode::GenerateAllocateArrayStub(Assembler* assembler) {
   Label slow_case;
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
 
   if (FLAG_inline_alloc) {
     // Compute the size to be allocated, it is based on the array length
-    // and it computed as:
+    // and is computed as:
     // RoundedAllocationSize((array_length * kwordSize) + sizeof(RawArray)).
     // Assert that length is a Smi.
     __ testq(R10, Immediate(kSmiTagSize));
     if (FLAG_use_slow_path) {
       __ jmp(&slow_case);
     } else {
       __ j(NOT_ZERO, &slow_case);
     }
     __ movq(R13, FieldAddress(CTX, Context::isolate_offset()));
     __ movq(R13, Address(R13, Isolate::heap_offset()));
@@ skipping 1246 matching lines @@
 // TOS + 2: instance.
 // TOS + 3: cache array.
 // Result in RCX: null -> not found, otherwise result (true or false).
 void StubCode::GenerateSubtype3TestCacheStub(Assembler* assembler) {
   GenerateSubtypeNTestCacheStub(assembler, 3);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64