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From: Jakub Jelinek <jakub@redhat.com>
To: Richard Biener <rguenther@suse.de>
Cc: fkastl@suse.cz, Gcc-patches <gcc-patches@gcc.gnu.org>,
	mjambor@suse.cz, hubicka@ucw.cz
Subject: Re: [RFC] gimple ssa: SCCP - A new PHI optimization pass
Date: Thu, 24 Aug 2023 17:54:54 +0200	[thread overview]
Message-ID: <ZOd9TpRQSGUrSCeU@tucnak> (raw)
In-Reply-To: <084BC52B-00DE-4496-8B85-9211C3AD8394@suse.de>

On Thu, Aug 24, 2023 at 05:47:09PM +0200, Richard Biener via Gcc-patches wrote:
> > Do you think that the pass is worthy of inclusion into upstream GCC? What are
> > some things that I should change? Should I try to put the pass in different
> > places in passes.def?
> 
> The most obvious places would be right after SSA construction and before RTL expansion.
> Can you provide measurements for those positions?
> Can the pass somehow be used as part of propagations like during value numbering?

Could the new file be called gimple-ssa-sccp.cc or something similar?
Removing some PHIs is nice, but it would be also interesting to know what
are the effects on generated code size and/or performance.
And also if it has any effects on debug information coverage.

	Jakub


  reply	other threads:[~2023-08-24 15:55 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-24 15:07 Filip Kastl
2023-08-24 15:47 ` Richard Biener
2023-08-24 15:54   ` Jakub Jelinek [this message]
2023-08-31 11:26     ` Filip Kastl
2023-08-31 11:44       ` Jakub Jelinek
2023-08-31 12:13       ` Richard Biener
2023-08-31 21:44         ` Andrew Pinski
2023-09-01  6:34           ` Richard Biener
2023-09-01 10:10         ` Filip Kastl
2023-09-01 10:53           ` Richard Biener

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