https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108764
--- Comment #4 from Sinan <sinan.lin at linux dot alibaba.com> --- (In reply to Andrew Pinski from comment #2) > slli a4,a2,3 > sh3add a5,a2,a0 > > vs > slli a2,a2,3 > add a5,a0,a2 > > I think the first one is better really because you have two indepedent > instructions and can be issued at the same time. > Really this is all core specific and the generic tuning should be "generic" > which means this is the correct tuning ... Thanks for pointing it out. This might not be a good case(I only notice the extra `mv` brought from zba). I just have a quick check with spec2017, and it seems that the current cost model indeed does a better job in terms of the dependency of slli && add.
