[Bug tree-optimization/105940] suggested_unroll_factor applying place looks wrong
linkw at gcc dot gnu.org
Tue Jun 14 08:46:10 GMT 2022
--- Comment #4 from Kewen Lin <linkw at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #2)
> (In reply to Kewen Lin from comment #1)
> > Created attachment 53126 [details]
> > move_applying
> LGTM (maybe the suggested unroll factor should be only applied if the
> suggestion was from a matching with/without SLP analysis, or in fact
> vect_analyze_loop_1 should communicate that down - disabling SLP when
> the one suggesting unrolling did the re-analysis).
Oops, just noticed the nice suggestion. Will make a follow up patch for this.
It would looks like:
when working out suggested unroll factor, save slp decision into one passed
down variable from vect_analyze_loop_1.
when applying suggested unroll factor, if the save slp is false, directly
ignore slp handlings, otherwise, go the normal slp path but won't start over
for slp off.
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