rjmccall added a comment. On the topic of supporting BF16 arithmetic, note my comment here: https://github.com/itanium-cxx-abi/cxx-abi/pull/147#issuecomment-1254078916. To summarize, according to Steve Canon, we really shouldn't implement arithmetic directly in the BF16 format, because the precision is simply too low to be useful. Instead, we need to guarantee excess-precision arithmetic so that we only truncate back to BF16 when the source code requires it. We can do that in the frontend using the same excess-precision logic we added for `_Float16`.
If Steve's argument is true, that suggests that it would be a waste for NVPTX hardware to directly support BF16 arithmetic, at least not the same way it would support `float` or `double`. (Providing operations like x86's VDPBF16PS — https://en.wikichip.org/wiki/x86/avx512_bf16 — that start from BF16 operands but perform their arithmetic in `float` is a different story.) Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D136919/new/ https://reviews.llvm.org/D136919 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
