[stubs] Split ToNumberStub into reusable subparts.

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/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 3857 matching lines @@
     Label ok;
     Condition is_smi = CheckSmi(object);
     j(is_smi, &ok, Label::kNear);
     Cmp(FieldOperand(object, HeapObject::kMapOffset),
         isolate()->factory()->heap_number_map());
     Check(equal, kOperandIsNotANumber);
     bind(&ok);
   }
 }
 
+void MacroAssembler::AssertNotNumber(Register object) {
+  if (emit_debug_code()) {
+    Condition is_smi = CheckSmi(object);
+    Check(NegateCondition(is_smi), kOperandIsANumber);
+    Cmp(FieldOperand(object, HeapObject::kMapOffset),
+        isolate()->factory()->heap_number_map());
+    Check(equal, kOperandIsANumber);
+  }
+}
 
 void MacroAssembler::AssertNotSmi(Register object) {
   if (emit_debug_code()) {
     Condition is_smi = CheckSmi(object);
     Check(NegateCondition(is_smi), kOperandIsASmi);
   }
 }
 
 
 void MacroAssembler::AssertSmi(Register object) {
@@ skipping 1784 matching lines @@
   movl(rax, dividend);
   shrl(rax, Immediate(31));
   addl(rdx, rax);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64