https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55583
--- Comment #7 from Hongtao.liu <crazylht at gmail dot com> --- i386 already has 12980(define_insn_and_split "*x86_shrd_2" 12981 [(set (match_operand:SI 0 "nonimmediate_operand") 12982 (ior:SI (lshiftrt:SI (match_dup 0) 12983 (match_operand:QI 2 "nonmemory_operand")) 12984 (ashift:SI (match_operand:SI 1 "register_operand") 12985 (minus:QI (const_int 32) (match_dup 2))))) It need to be extended(or has new pre_reload splitters) to handle 1. op2 is constant, so minus is not necessary here. 2. swap op2 and (minus:QI (const_int 32) (match_dup 2) between lshiftrt and ashift. 3. match_dup 0 is too restrict, we can have a extra emit_move_insn to set DEST.
