From: ibuclaw@gdcproject.org
To: "Jeff Law" <jeffreyalaw@gmail.com>,
"Jeff Law via Gcc-patches" <gcc-patches@gcc.gnu.org>,
"Luís Ferreira" <contact@lsferreira.net>
Subject: Re: [PATCH] libiberty: d-demangle: use switch instead of if-else
Date: Mon, 4 Oct 2021 09:25:14 +0200 (CEST) [thread overview]
Message-ID: <248182573.176926.1633332314228@office.mailbox.org> (raw)
In-Reply-To: <43f9005e-bc54-842b-b7c2-d3e899d8714f@gmail.com>
> On 03/10/2021 23:55 Jeff Law via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>
>
> On 9/29/2021 7:08 PM, Luís Ferreira wrote:
> > This patch allows the compiler to efficiently generate jump tables instead of
> > using if-else-if.
> >
> > Signed-off-by: Luís Ferreira <contact@lsferreira.net>
> I'm not sure this is terribly useful. Compilers have the ability to
> analyze the underlying code and make sensible decisions for how to
> implement either form. So the right metric here is does this make the
> code cleaner/easier to understand. With just 3 clauses it's hard (for
> me) to make the case that it is considerably cleaner.
>
I'd be inclined to agree here.
FAOD, I put together a quick example of what difference this patch makes. Other than freely reordering the conditions, the answer is nothing.
https://godbolt.org/z/nKjjv64zM
Iain.
next prev parent reply other threads:[~2021-10-04 7:25 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-30 1:08 Luís Ferreira
2021-10-03 21:55 ` Jeff Law
2021-10-04 7:25 ` ibuclaw [this message]
2021-10-04 14:56 ` Luís Ferreira
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