https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126671
Vincenzo Romano <vincenzo.romano at gmail dot com> changed:
What |Removed |Added
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CC| |vincenzo.romano at gmail dot
com
--- Comment #1 from Vincenzo Romano <vincenzo.romano at gmail dot com> ---
This is confirmed for current trunk with "-march=rv64gcb_zbkb -mabi=lp64":
__builtin_bitreverse64() does not emit the expected sequence:
rev8 a0, a0
brev8 a0, a0
but rather the usual 20+ instruction bit swapping sequence.
CLANG does it correctly since v19.1.0
It can be seen in action here:
https://godbolt.org/z/67z4cKnzn
