[PATCH] D130964: [X86][BF16] Enable __bf16 for x86 targets.

Tue Aug 2 13:04:58 PDT 2022

bkramer added a comment.

In D130964#3694473 <https://reviews.llvm.org/D130964#3694473>, @rjmccall wrote:

> How are you actually implementing `__bf16` on these targets?  There isn't even hardware support for conversions.

`bf16` -> `float` is really just a bit shift. The other direction gets lowered to a libcall, compiler-rt has a conversion function with proper rounding. I added some support to make the backend promote all other arithmetic to float, but I think that's only enabled on x86 so far.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130964/new/

https://reviews.llvm.org/D130964