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From: "tschwinge at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug target/104345] [12 Regression] "nvptx: Transition nvptx backend
 to STORE_FLAG_VALUE = 1" patch made some code generation worse
Date: Tue, 08 Feb 2022 12:33:03 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104345

--- Comment #8 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
Well.  Here's another problem.

Re-testing things using a "bad" '__muldc3' from a build with your three pat=
ches
applied, I notice that my '_muldc3-WIP.o' "old"/replacement code uses a
'set.u32.leu.f64', 'neg.s32', 'mov.u32' sequence.  That works.
However, if I replace that with a localized (its own '.reg .pred %r138_;')
'setp.leu.f64', 'selp.u32' sequence (as per your code generation changes), =
then
it doesn't in fact work!  Huh.

Will later continue looking into this.=