https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115176
Xi Ruoyao <xry111 at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |xry111 at gcc dot gnu.org
--- Comment #2 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
LoongArch currently has:
(define_insn "bitrev_4b"
[(set (match_operand:SI 0 "register_operand" "=r")
(unspec:SI [(match_operand:SI 1 "register_operand" "r")]
UNSPEC_BITREV_4B))]
""
"bitrev.4b\t%0,%1"
[(set_attr "type" "unknown")
(set_attr "mode" "SI")])
(define_insn "bitrev_8b"
[(set (match_operand:DI 0 "register_operand" "=r")
(unspec:DI [(match_operand:DI 1 "register_operand" "r")]
UNSPEC_BITREV_8B))]
""
"bitrev.8b\t%0,%1"
[(set_attr "type" "unknown")
(set_attr "mode" "DI")])
Maybe we can make them something like (subreg:DI (bitreverse:V8QI (subreg:QI
(match...) 0)) 0) instead. And LoongArch also has bitrev.{w/d} instructions
but GCC doesn't know them yet. I plan to add them after PR50481 is
implemented.
