https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103216
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Andrew Pinski from comment #1) > For x86_64 we might be able to solve this at the RTL level during combine: > (set (reg/v:QI 84 [ <retval> ]) > (if_then_else:QI (lt (subreg:QI (reg:SI 86 [ a ]) 0) > (const_int 0 [0])) > (ior:QI (subreg:QI (reg:SI 86 [ a ]) 0) > (const_int -128 [0xffffffffffffff80])) > (reg/v:QI 84 [ <retval> ]))) > > That is optimize: > (a < 0) ? a | signbit : b > to > (a < 0) ? a : b That didn't work either because combine could put back into place the lt.
