Re: 'setobj' in lua-5.4.0-alpha-rc2 become more faster

[云风 Cloud Wu <cloudwu@...>]

重归混沌 <findstrx@gmail.com> 于2019年6月14日周五 下午2:33写道：
> `
>      #define setobj(L,obj1,obj2) \
> -    { TValue *io1=(obj1); *io1 = *(obj2); \
> +    { TValue *io1=(obj1); const TValue *io2=(obj2); \
> +         io1->value_ = io2->value_; io1->tt_ = io2->tt_; \
>            (void)L; checkliveness(L,io1); }
>
> `
>
> I disassembled this change, and can't find the key point.
>
> So, who can't point me the key? Thank you very much.

Because the sizeof(TValue) is 16 bytes on 64 bit platform, but
sizeof(obj->value_) + sizeof(obj->tt_) is 9 bytes.


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