https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107671
--- Comment #3 from Hongtao.liu <crazylht at gmail dot com> --- We already have ----------cut from i386.md-------- 15204;; Help combine recognize bt followed by setc 15205(define_insn_and_split "*bt<mode>_setcqi" 15206 [(set (subreg:SWI48 (match_operand:QI 0 "register_operand") 0) 15207 (zero_extract:SWI48 15208 (match_operand:SWI48 1 "register_operand") 15209 (const_int 1) 15210 (zero_extend:SI (match_operand:QI 2 "register_operand")))) 15211 (clobber (reg:CC FLAGS_REG))] 15212 "TARGET_USE_BT && ix86_pre_reload_split ()" .... 15262;; Help combine recognize bt followed by setnc 15263(define_insn_and_split "*bt<mode>_setncqi" 15264 [(set (match_operand:QI 0 "register_operand") 15265 (and:QI 15266 (not:QI 15267 (subreg:QI 15268 (lshiftrt:SWI48 (match_operand:SWI48 1 "register_operand") 15269 (match_operand:QI 2 "register_operand")) 0)) 15270 (const_int 1))) 15271 (clobber (reg:CC FLAGS_REG))] 15272 "TARGET_USE_BT && ix86_pre_reload_split ()" 15273 "#" 15274 "&& 1" -----------cut end------------- Guess we need more variants for that.
