[PATCH] D71124: [RISCV] support clang driver to select cpu

[Kito Cheng via Phabricator via cfe-commits]

kito-cheng added a comment.

Another proposal for -mcpu and -mtune:

Decoupling the -mcpu and -mtune option, -mcpu only accept concrete CPU, and -mtune for micro-arch/pipeline model, they accept different option set.

e.g.
-mcpu=sifive-e24 # Imply -march=rv32imafc -mtune=sifive-2-series
-mtune=sifive-2-series # no effect on arch
-mtune=rocket # no effect on arch

So -mcpu=rocket is invalid, since it's micro-arch/pipeline model only,
and -mtune=sifive-e24 is invalid too, because it's CPU not a micro-arch.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D71124/new/

https://reviews.llvm.org/D71124