https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99259
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
v0 wasn't used for x and y, but for acc and x. As you said, when acc is both
input and output, you need +w or "=w" (acc) ..... "0" (acc), but even if it was
output only and couldn't clash with x or y, you'd need early-clobber - "=&w"
which would make sure that the input operands get different registers from that
output one.
