Optionally use 31-bits SMI value for 64-bit system

src/x64/stub-cache-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3038 matching lines @@
   __ CheckMap(key,
               masm->isolate()->factory()->heap_number_map(),
               fail,
               DONT_DO_SMI_CHECK);
   __ movsd(xmm_scratch0, FieldOperand(key, HeapNumber::kValueOffset));
   __ cvttsd2si(scratch, xmm_scratch0);
   __ cvtlsi2sd(xmm_scratch1, scratch);
   __ ucomisd(xmm_scratch1, xmm_scratch0);
   __ j(not_equal, fail);
   __ j(parity_even, fail);  // NaN.
+#if V8_USE_31_BITS_SMI_VALUE
+  __ cmpl(scratch, Immediate(0xc0000000));
+  __ j(sign, fail);
+#endif
   __ Integer32ToSmi(key, scratch);
   __ bind(&key_ok);
 }
 
 
 void KeyedStoreStubCompiler::GenerateStoreExternalArray(
     MacroAssembler* masm,
     ElementsKind elements_kind) {
   // ----------- S t a t e -------------
   //  -- rax    : value
@@ skipping 443 matching lines @@
     TailCallBuiltin(masm, Builtins::kKeyedStoreIC_Slow);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64