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From: "segher at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/65010] ppc backend generates unnecessary signed
 extension
Date: Thu, 29 Feb 2024 21:47:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D65010

--- Comment #13 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to pthaugen from comment #11)
> Another example to clean up. The back to back constant load/sign extend
> sequence of rtl insns is created in each block by the block reordering pa=
ss
> (.bbo) duplicating the common return block.

(.bbro)

That pass is way late, so you do not get any of the more basic optimisations
after it :-(  We either need to move this pass earlier, or do this before
cprop3
and cse2 as well already, or somehow do a minimal version of all that basic
stuff
in bbro itself?=