https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126932
--- Comment #6 from Robin Dapp <rdapp at gcc dot gnu.org> --- (In reply to Jeffrey A. Law from comment #4) > So do we know how/why x86 is avoiding this. The only reference I see to the > fp contract in the x86 backend is in the vector costing model. combine will combine (plus ...) and (mult ...) into (plus (mult ...)) but not into (fma ...). Our patterns use the former and not the latter so we'll get spurious combinations that don't check ffp-contract.
