On Sat, Feb 15, 2014 at 10:45 AM, Prathamesh Kulkarni <bilbotheelffri...@gmail.com> wrote: > On Sat, Feb 15, 2014 at 2:28 PM, Jakub Jelinek <ja...@redhat.com> wrote: >> On Sat, Feb 15, 2014 at 02:23:24PM +0530, Prathamesh Kulkarni wrote: >>> This patch folds strchr (e, 0) to e + strlen (e), if e has no side-effects. >>> Bootstrapped, regtested on x86_64-unknown-linux-gnu >>> Ok for trunk ? >> >> Why do you think it is a good idea? It is often very much the opposite. > I maybe completely wrong, but since strchr(p, 0), matches each > character of p with c until '\0' is found, I thought it would be > faster to call strlen, since strlen would just skip over characters upto '\0'. > Also, I saw this committed in llvm trunk recently, and thought it > might be a good idea: > http://llvm-reviews.chandlerc.com/rL200736
If it ends up being a good idea then please add this transform to tree-ssa-strlen.c, not to GENERIC builtins folding. Richard. >> >> Jakub
