https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101325
--- Comment #8 from Christophe Lyon <clyon at gcc dot gnu.org> --- Indeed, it's what happens in try_combine(): i2src = subst (i2src, pc_rtx, pc_rtx, 0, 0, 0); converts i2src (zero_extend:SI (reg:HI 117)) into: (and:SI (subreg:SI (reg:HI 117) 0) (const_int 1 [0x1]))