https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87330
Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |ebotcazou at gcc dot gnu.org
--- Comment #7 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> the regrename pass does not rename the registers which are in notes, because
> of which the REG_DEAD note had previous regname, which caused conflicting
> information generated for tag collision pass.
Yes, that's by design, RTL passes need not update REG_DEAD & REG_UNUSED notes.
Instead passes that consume them must recompute them on entry by means of DF.
