* Re: [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refactor to follow GNU coding standards [not found] ` <20170211125134.80F4325FCF@vcs0.savannah.gnu.org> @ 2017-02-11 15:46 ` Stefan Monnier 2017-02-11 18:13 ` Vibhav Pant 0 siblings, 1 reply; 2+ messages in thread From: Stefan Monnier @ 2017-02-11 15:46 UTC (permalink / raw) To: emacs-devel; +Cc: Vibhav Pant > + 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). Stefan ^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refactor to follow GNU coding standards 2017-02-11 15:46 ` [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refactor to follow GNU coding standards Stefan Monnier @ 2017-02-11 18:13 ` Vibhav Pant 0 siblings, 0 replies; 2+ messages in thread From: Vibhav Pant @ 2017-02-11 18:13 UTC (permalink / raw) To: Stefan Monnier; +Cc: emacs-devel@gnu.org On Sat, Feb 11, 2017 at 9:16 PM, Stefan Monnier <monnier@iro.umontreal.ca> 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 vibhavp@gmail.com ^ permalink raw reply [flat|nested] 2+ messages in thread
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2017-02-11 15:46 ` [Emacs-diffs] feature/byte-switch a75d080: * src/bytecode.c: Refactor to follow GNU coding standards Stefan Monnier
2017-02-11 18:13 ` Vibhav Pant
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