https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120050
Richard Sandiford <rsandifo at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |rsandifo at gcc dot gnu.org
--- Comment #8 from Richard Sandiford <rsandifo at gcc dot gnu.org> ---
When it comes to avoiding things for correctness reasons, I think the key
should be TRULY_NOOP_TRUNCATION rather than mode_rep_extended.
mode_rep_extended was added later to provide optimisation information about
what the upper bits are guaranteed to contain, but in principle, the upper bits
might not be a simple sign or zero extension even when TRULY_NOOP_TRUNCATION is
false.
