Agreed policy is that RISC-V extensions that have not yet been ratified
should be marked as experimental, and enabling them requires the use of
the -menable-experimental-extensions flag when using clang alongside the
version number. These extensions have now been ratified, so this is no
longer necessary, and the target feature names can be renamed to no
longer be prefixed with "experimental-".
Differential Revision: https://reviews.llvm.org/D117131
At this point it looks like a B extension will never exist. Instead
Zba, Zbb, Zbc, and Zbs are individual extensions being ratified
together as a package. Unknown at this time when or if the other
Zb* extensions will be ratified.
This patch removes references to the B extension. I've updated and
split tests accordingly.
This has been split from D110669 to make review a little easier.
Differential Revision: https://reviews.llvm.org/D111338
This will tell loop idiom recognize that it can make popcount loops countable
using the ctpop intrinsic. I didn't bother checking for illegal types.
Type legalization knows how to split a ctpop into multiple ctops added together.
Assuming we only receive reasonable integer bit widths, a few cpop instructions
added together is probably better than the loop.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D99203