From: Segher Boessenkool <segher@kernel.crashing.org>
To: Andrea Corallo <andrea.corallo@arm.com>
Cc: stefan@franke.ms, gcc-help@gcc.gnu.org
Subject: Re: Correct way to express to the compiler "this does not get clobbered"?
Date: Fri, 4 Dec 2020 11:27:21 -0600 [thread overview]
Message-ID: <20201204172721.GM2672@gate.crashing.org> (raw)
In-Reply-To: <gkrv9dhgapa.fsf@arm.com>
On Fri, Dec 04, 2020 at 10:52:17AM +0100, Andrea Corallo via Gcc-help wrote:
> stefan@franke.ms writes:
> I might open a bug but my understanding is that const is generally
> not used for optimizations. Am I wrong?
extern const int x = 42;
int f(void) { return x; }
The code generated for f does not load the value for x from memory: it
returns 42 always.
Segher
next prev parent reply other threads:[~2020-12-04 17:28 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-03 11:47 Andrea Corallo
2020-12-03 12:04 ` Richard Earnshaw
2020-12-03 12:28 ` Andrea Corallo
2020-12-03 13:06 ` Richard Earnshaw
2020-12-03 13:40 ` Andrea Corallo
2020-12-03 18:24 ` David Brown
2020-12-03 23:00 ` Andrea Corallo
2020-12-04 7:23 ` stefan
2020-12-04 9:52 ` Andrea Corallo
2020-12-04 17:27 ` Segher Boessenkool [this message]
2020-12-04 18:16 ` Andrea Corallo
2020-12-04 18:33 ` Segher Boessenkool
2020-12-04 18:45 ` Andrea Corallo
[not found] ` <017701d6ca6d$7dc8dc90$795a95b0$@bebbosoft.de>
2020-12-04 18:57 ` AW: " Stefan Franke
2020-12-04 22:52 ` Andrea Corallo
2020-12-05 14:01 ` David Brown
2020-12-05 14:17 ` AW: " Stefan Franke
2020-12-05 18:10 ` Andrea Corallo
2020-12-07 22:27 ` Segher Boessenkool
2020-12-05 19:03 ` David Brown
2020-12-06 11:29 ` AW: " Stefan Franke
2020-12-05 17:29 ` Andrea Corallo
2020-12-05 19:07 ` David Brown
2020-12-06 9:22 ` Jonathan Wakely
2020-12-04 8:27 ` David Brown
2020-12-04 10:05 ` Andrea Corallo
2020-12-05 8:06 ` Liu Hao
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