>> 3. Your SPEC FP benchmarks tell me two things: GCC 4.4's fortran support is >> dramatically better than 4.2's (which llvm 2.5 uses), and your art/mgrid >> hacks apparently do great stuff :). > > Something like the "art hack" is in ipa-struct-reorg, but it is not > enabled at any level. If gcc outperforms llvm on art by much, it's > more likely that some important opportunities for art are being > overlooked by llvm. > > There also isn't anything special done for mgrid, except predictive > commoning (CSE around loops) which is not a hack, in the sense it is > helpful for a lot of numerical code and triggers several times in > things like generic Fortran blas/lapack routines.
Indeed, we have a couple of benchmark-inspired optimizations for SPEC2006 (division/modulo power-of-two, see PR26026; and ifcombine), and we optimize MATMUL (TRANSPOSE (A), B) which helps galgel a lot. But both of this may trigger quite a lot on other code, and LLVM also benefits from the galgel one :-) because it's done in the front-end. Paolo
