[all-commits] [llvm/llvm-project] 73eecc: [mlir] Convert 8-bit float types to i8

[Krzysztof Drewniak via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 73eecc9ca4db5730a77e7f4144d93696c9a1c5a3
      https://github.com/llvm/llvm-project/commit/73eecc9ca4db5730a77e7f4144d93696c9a1c5a3
  Author: Krzysztof Drewniak <Krzysztof.Drewniak at amd.com>
  Date:   2023-06-26 (Mon, 26 Jun 2023)

  Changed paths:
    M mlir/include/mlir/Conversion/LLVMCommon/TypeConverter.h
    M mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
    M mlir/lib/Conversion/LLVMCommon/TypeConverter.cpp
    M mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
    M mlir/test/Target/LLVMIR/llvmir.mlir

  Log Message:
  -----------
  [mlir] Convert 8-bit float types to i8

Whereas LLVM currently doesn't have any types for 8-bit floats, and
whereas existing 8-bit float APIs (for instance, the AMDGCN
intrinsics) take such floats as (packed) bytes, translate the MLIR
8-bit float types to i8 during LLVM lowering.

In order to not special-case arith.constant for bitcasting constants
to their integer form, amend the MLIR to LLVM translator to turn 8-bit
float constants into i8 constants with the same value (by use of
APFloat's bitcast method).

This change can be reverted once LLVM has 8-bit float types.

Reviewed By: gysit

Differential Revision: https://reviews.llvm.org/D153160