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Re: [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refacto

From: Vibhav Pant
Subject: Re: [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refactor to follow GNU coding standards
Date: Sat, 11 Feb 2017 23:43:02 +0530

On Sat, Feb 11, 2017 at 9:16 PM, Stefan Monnier
<address@hidden> wrote:
>> +                    if (BYTE_CODE_SAFE)
>> +                      eassert (!NILP (HASH_HASH (h, i)));
> Declaring that non-full hashtables are "dangerous" is rather annoying.
> In this case, I think we can do better:
>                  Lisp_Object hash_code
>                    = make_number (h->test.hashfn (&h->test, v1));
> this then lets us use EQ (hash_code, ...) instead of hash_code == XUINT
> (...)  which not only correctly skips nil hashes but might even be ever
> so slightly faster (both use == on the same size of integers, but the
> former avoids the cost of XUINT).

Indeed. Since we only use hash_code when h->test.cmpfn is not NULL,
calculating it only then would also make sense (at the cost of an
extra NULL check).

Vibhav Pant

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