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Subject: Re: [PATCH v2] Add if-chain to switch conversion pass.
To: Richard Biener <richard.guenther@gmail.com>
Cc: David Malcolm <dmalcolm@redhat.com>, Jakub Jelinek <jakub@redhat.com>,
 GCC Patches <gcc-patches@gcc.gnu.org>, Jan Hubicka <hubicka@ucw.cz>
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From: =?UTF-8?Q?Martin_Li=c5=a1ka?= <mliska@suse.cz>
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Date: Wed, 18 Nov 2020 13:25:43 +0100
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On 11/16/20 1:21 PM, Richard Biener wrote:
> but the most trivial thing would be to feed the pass the
> balanced-tree generated by switch expansion where I
> would expect us to be able to detect it as the original switch again.

Well, if we want to support such matching, then please deffer it to a phase 2.
I don't see it a common pattern that people write such a code in wild.

Right now, we have some local analysis and one can eventually build a more advanced
algorithm on top of it. Can we please make a progress for GCC 11 with the current
approach that will cover quite some interesting if-chains?

Thanks,
Martin