[PATCH] D34815: [Power9] Spill gprs to vector registers rather than stack

[Nemanja Ivanovic via Phabricator via llvm-commits]

nemanjai added a comment.

Overall, I like the patch. Seems quite nice and simple. However, I'm really not a fan of the naming convention. It is not clear to me why someone would be expected to make the connection between "GPFPRC" and "VSRSPILL". I think those should use the same base name to make the connection clear. Furthermore, I don't really think you should convey what registers are in the register class, but what the register class is used for. Perhaps the class and the related artifacts should be something like `SPILLTOVSRRC` and `SPILLTOVSR_LD`, etc. Perhaps other reviewers can chime in here as well.

Also, I think an important opportunity is lost since we don't do this for `GPRRC`. Of course, it doesn't have to be done in this patch, but I think a comment including a `FIXME` indicating this limitation is in order. Then if this turns out to be a performance win, we can follow this up with a patch that handles the 32-bit registers as well.


https://reviews.llvm.org/D34815