https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87763
--- Comment #25 from Jakub Jelinek <jakub at gcc dot gnu.org> --- We have BIT_INSERT_EXPR on GIMPLE, which in the end is a quarternary operation previous value, value to insert, bit position and bit size (the last one is implicit in this GIMPLE op), so you're arguing we should have a similar expression in RTL, right? Say BIT_INSERT or INSV?
