https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71206
--- Comment #4 from Marc Glisse <glisse at gcc dot gnu.org> --- I am starting a bootstrap+regtest with: /* (X ^ Y) ^ (X ^ Z) -> Y ^ Z */ (simplify (bit_xor (convert1? (bit_xor:c @0 @1)) (convert2? (bit_xor:c @0 @2))) (if (tree_nop_conversion_p (type, TREE_TYPE (@1)) && tree_nop_conversion_p (type, TREE_TYPE (@2))) - (convert (bit_xor @1 @2)))) + (bit_xor (convert @1) (convert @2))))