[Builtins] Smi-check the spread and go to runtime in CheckSpreadAndPushToStack.

src/builtins/x87/builtins-x87.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_X87
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 2704 matching lines @@
   Register argc = eax;
 
   Register scratch = ecx;
   Register scratch2 = edi;
 
   Register spread = ebx;
   Register spread_map = edx;
 
   Register spread_len = edx;
 
+  Label runtime_call, push_args;
   __ mov(spread, Operand(esp, kPointerSize));
+  __ JumpIfSmi(spread, &runtime_call);
   __ mov(spread_map, FieldOperand(spread, HeapObject::kMapOffset));
 
-  Label runtime_call, push_args;
   // Check that the spread is an array.
   __ CmpInstanceType(spread_map, JS_ARRAY_TYPE);
   __ j(not_equal, &runtime_call);
 
   // Check that we have the original ArrayPrototype.
   __ mov(scratch, FieldOperand(spread_map, Map::kPrototypeOffset));
   __ mov(scratch2, NativeContextOperand());
   __ cmp(scratch,
          ContextOperand(scratch2, Context::INITIAL_ARRAY_PROTOTYPE_INDEX));
   __ j(not_equal, &runtime_call);
@@ skipping 603 matching lines @@
 
 void Builtins::Generate_InterpreterOnStackReplacement(MacroAssembler* masm) {
   Generate_OnStackReplacementHelper(masm, true);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87