[PATCH] D10416: Use function attribute "arm-restrict-it"

Jim Grosbach via llvm-commits llvm-commits at lists.llvm.org
Tue Sep 8 11:31:39 PDT 2015

grosbach added a comment.

For the backend attribute, having -arm-restrict-it (or equivalent) transitively disable HasV8Ops is really, really bad. Those should be completely independent selections. The former is about tuning instruction selection (via if-conversion in this case) based on the microarchitecture. The latter is about which instructions are available in the first place. The former does not imply the latter.

I don't think there's much point to disabling restrict-it when targeting v8 from an end-user POV, but it's pretty useful for the backend. We want to be able to write test cases that make sure it's working, for example.

Do I understand right there's a frontend option, too? That's the only context in which gcc compatibility makes much sense. I don't see any value other than slavishly following gcc's option list to having this be exposed to end users in clang. I'd much rather it be entirely in the backend.


More information about the llvm-commits mailing list