[PATCH] D150913: [Clang][Bfloat16] Upgrade __bf16 to arithmetic type, change mangling, and extend excess precision support.

[M. Zeeshan Siddiqui via Phabricator via cfe-commits]

codemzs created this revision.
codemzs added reviewers: tahonermann, rjmccall, zahiraam, stuij, pengfei, erichkeane.
Herald added subscribers: mattd, gchakrabarti, asavonic, kerbowa, kristof.beyls, jvesely.
Herald added a project: All.
codemzs requested review of this revision.
Herald added subscribers: cfe-commits, MaskRay, jholewinski.
Herald added a project: clang.

Pursuant to RFC <https://discourse.llvm.org/t/rfc-c-23-p1467r9-extended-floating-point-types-and-standard-names/70033/22> discussions, this change enhances the handling of the `__bf16` type in Clang.

- Firstly, it upgrades `__bf16` from a storage-only type to an arithmetic type.
- Secondly, it changes the mangling of `__bf16` to `DF16b` on all architectures except ARM. This change has been made in accordance with the finalization of the mangling for the `std::bfloat16_t` type, as discussed at https://github.com/itanium-cxx-abi/cxx-abi/pull/147.
- Finally, this commit extends the existing excess precision support to the `__bf16` type. This applies to hardware architectures that do not natively support `bfloat16` arithmetic.

Appropriate tests have been added to verify the effects of these changes and ensure no regressions in other areas of the compiler.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D150913

Files:
  clang/include/clang/AST/ASTContext.h
  clang/include/clang/Basic/DiagnosticSemaKinds.td
  clang/include/clang/Basic/FPOptions.def
  clang/include/clang/Basic/LangOptions.def
  clang/include/clang/Basic/TargetInfo.h
  clang/include/clang/Driver/Options.td
  clang/lib/AST/Type.cpp
  clang/lib/Basic/TargetInfo.cpp
  clang/lib/Basic/Targets/AMDGPU.h
  clang/lib/Basic/Targets/ARM.cpp
  clang/lib/Basic/Targets/NVPTX.h
  clang/lib/Basic/Targets/X86.cpp
  clang/lib/Basic/Targets/X86.h
  clang/lib/CodeGen/CGExprScalar.cpp
  clang/lib/Driver/ToolChains/Clang.cpp
  clang/lib/Sema/SemaCast.cpp
  clang/lib/Sema/SemaExpr.cpp
  clang/lib/Sema/SemaOverload.cpp
  clang/test/CodeGen/X86/avx512bf16-error.c
  clang/test/CodeGen/X86/bfloat-mangle.cpp
  clang/test/CodeGen/X86/bfloat16.cpp
  clang/test/CodeGen/X86/fexcess-precision-bfloat16.c
  clang/test/CodeGenCUDA/amdgpu-bf16.cu
  clang/test/CodeGenCUDA/bf16.cu
  clang/test/Driver/fexcess-precision.c
  clang/test/Sema/arm-bf16-forbidden-ops.c
  clang/test/Sema/arm-bf16-forbidden-ops.cpp
  clang/test/Sema/arm-bfloat.cpp
  clang/test/SemaCUDA/amdgpu-bf16.cu
  clang/test/SemaCUDA/bf16.cu

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D150913.523582.patch
Type: text/x-patch
Size: 70175 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20230518/c189b113/attachment-0001.bin>