[builtins] Start refactoring the Apply builtin.

src/x64/macro-assembler-x64.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/base/utils/random-number-generator.h"
 #include "src/bootstrapper.h"
@@ skipping 3683 matching lines @@
 }
 
 
 void MacroAssembler::AssertSmi(const Operand& object) {
   if (emit_debug_code()) {
     Condition is_smi = CheckSmi(object);
     Check(is_smi, kOperandIsNotASmi);
   }
 }
 
+void MacroAssembler::AssertFixedArray(Register object) {
+  if (emit_debug_code()) {
+    testb(object, Immediate(kSmiTagMask));
+    Check(not_equal, kOperandIsASmiAndNotAFixedArray);
+    Push(object);
+    CmpObjectType(object, FIXED_ARRAY_TYPE, object);
+    Pop(object);
+    Check(equal, kOperandIsNotAFixedArray);
+  }
+}
 
 void MacroAssembler::AssertZeroExtended(Register int32_register) {
   if (emit_debug_code()) {
     DCHECK(!int32_register.is(kScratchRegister));
     movq(kScratchRegister, V8_INT64_C(0x0000000100000000));
     cmpq(kScratchRegister, int32_register);
     Check(above_equal, k32BitValueInRegisterIsNotZeroExtended);
   }
 }
 
@@ skipping 1333 matching lines @@
   movl(rax, dividend);
   shrl(rax, Immediate(31));
   addl(rdx, rax);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64