Hello! We are splitting it to normal XOR that includes clobber, so better start with the clobber from the beginning.
2013-10-20 Uros Bizjak <ubiz...@gmail.com> * config/i386/i386.md (kxnor<mode>): Add FLAGS_REG clobber. Tested on x86_64-pc-linux-gnu and committed to mainline SVN. Uros.
Index: i386.md =================================================================== --- i386.md (revision 203885) +++ i386.md (working copy) @@ -8254,7 +8253,8 @@ (not:SWI12 (xor:SWI12 (match_operand:SWI12 1 "register_operand" "0,Yk") - (match_operand:SWI12 2 "register_operand" "r,Yk"))))] + (match_operand:SWI12 2 "register_operand" "r,Yk")))) + (clobber (reg:CC FLAGS_REG))] "TARGET_AVX512F" "@ # @@ -8268,15 +8268,15 @@ (not:SWI12 (xor:SWI12 (match_dup 0) - (match_operand:SWI12 1 "general_reg_operand"))))] + (match_operand:SWI12 1 "general_reg_operand")))) + (clobber (reg:CC FLAGS_REG))] "TARGET_AVX512F && reload_completed" [(parallel [(set (match_dup 0) (xor:HI (match_dup 0)