[Bug target/65871] bzhi builtin/intrinsic wrongly assumes bzhi instruction doesn't set the ZF flag

["ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65871

Uroš Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-04-28
     Ever confirmed|0                           |1

--- Comment #3 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to James Almer from comment #1)
> The same apparently happens with bextr, blsi, blsr, and most (if not all) of
> AMD's tbm instructions. They set the ZF flag but gcc still generates a test
> instruction.

Please see the patch, attached in Comment #2.

While I can see the use (and benefit) to model the patterns that also set CC
register internally for BEXTR and BZHI instructions, I don't think other listed
instructions have clear usage scenarios to warrant additional patterns.

Can you perhaps show the benefit to have more insns modelled this way?
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Subject: [Bug libstdc++/61645] forward_list::splice_after shall not throw exceptions
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ida645

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
done