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

src/builtins/mips/builtins-mips.cc

Index: src/builtins/mips/builtins-mips.cc
diff --git a/src/builtins/mips/builtins-mips.cc b/src/builtins/mips/builtins-mips.cc
index b6b6a5f715d50fc56afc0a428269fe6dca10de78..ded39d4d57ca95adc33ec976bd5e78d8e0b26ca8 100644
--- a/src/builtins/mips/builtins-mips.cc
+++ b/src/builtins/mips/builtins-mips.cc
@@ -2643,11 +2643,12 @@ static void CheckSpreadAndPushToStack(MacroAssembler* masm) {
 
   Register native_context = t4;
 
+  Label runtime_call, push_args;
   __ lw(spread, MemOperand(sp, 0));
+  __ JumpIfSmi(spread, &runtime_call);
   __ lw(spread_map, FieldMemOperand(spread, HeapObject::kMapOffset));
   __ lw(native_context, NativeContextMemOperand());
 
-  Label runtime_call, push_args;
   // Check that the spread is an array.
   __ lbu(scratch, FieldMemOperand(spread_map, Map::kInstanceTypeOffset));
   __ Branch(&runtime_call, ne, scratch, Operand(JS_ARRAY_TYPE));