[stubs] Split ToNumberStub into reusable subparts.

src/arm64/macro-assembler-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.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 1672 matching lines @@
 void MacroAssembler::AssertPositiveOrZero(Register value) {
   if (emit_debug_code()) {
     Label done;
     int sign_bit = value.Is64Bits() ? kXSignBit : kWSignBit;
     Tbz(value, sign_bit, &done);
     Abort(kUnexpectedNegativeValue);
     Bind(&done);
   }
 }
 
+void MacroAssembler::AssertNotNumber(Register value) {
+  if (emit_debug_code()) {
+    STATIC_ASSERT(kSmiTag == 0);
+    Tst(value, kSmiTagMask);
+    Check(ne, kOperandIsANumber);
+    Label done;
+    JumpIfNotHeapNumber(value, &done);
+    Abort(kOperandIsANumber);
+    Bind(&done);
+  }
+}
+
 void MacroAssembler::AssertNumber(Register value) {
   if (emit_debug_code()) {
     Label done;
     JumpIfSmi(value, &done);
     JumpIfHeapNumber(value, &done);
     Abort(kOperandIsNotANumber);
     Bind(&done);
   }
 }
 
@@ skipping 3356 matching lines @@
 }
 
 
 #undef __
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64