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Re: RFC: Patch for switch elimination (PR 54742)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Richard Biener <richard dot guenther at gmail dot com>
- Cc: Jeff Law <law at redhat dot com>, Steve Ellcey <sellcey at mips dot com>, GCC Patches <gcc-patches at gcc dot gnu dot org>, james dot greenhalgh at arm dot com
- Date: Thu, 4 Sep 2014 15:06:51 +0200
- Subject: Re: RFC: Patch for switch elimination (PR 54742)
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- Reply-to: Jakub Jelinek <jakub at redhat dot com>
On Thu, Sep 04, 2014 at 02:57:47PM +0200, Richard Biener wrote:
> Note that I think we arrived at the point where the loop structure
> has annotations that are required for correctness :/ (simduid
> for example - if that goes away we do ...? ICE? generate
> wrong code? I don't know - Jakub shoud).
For safelen loops it will be just (perhaps serious) missed-optimization,
for simduid I believe it shouldn't ICE either, the IFN_GOMP* builtins would
just fold as if the vectorization factor was 1 if the loop goes away.
But it will be even significantly bigger missed-optimization.
Jakub