[all-commits] [llvm/llvm-project] ad6698: [AMDGPU] V_LDEXP_F16 encoding fix and doc update.

Joe Nash via All-commits all-commits at lists.llvm.org
Wed Oct 19 06:53:24 PDT 2022


  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: ad6698562c3d43d0311922e7f6aebb8998021530
      https://github.com/llvm/llvm-project/commit/ad6698562c3d43d0311922e7f6aebb8998021530
  Author: Joe Nash <Joseph.Nash at amd.com>
  Date:   2022-10-19 (Wed, 19 Oct 2022)

  Changed paths:
    M llvm/include/llvm/IR/IntrinsicsAMDGPU.td
    M llvm/lib/Target/AMDGPU/VOP2Instructions.td
    M llvm/test/CodeGen/AMDGPU/llvm.amdgcn.ldexp.f16.ll
    M llvm/test/MC/AMDGPU/gfx11_asm_vop2_t16_err.s
    M llvm/test/MC/AMDGPU/gfx11_asm_vop2_t16_promote.s

  Log Message:
  -----------
  [AMDGPU] V_LDEXP_F16 encoding fix and doc update.

The amdgcn.ldexp.* intrinsics take an i32 value as src1.
The V_LDEXP_F16 instruction considers src1 an f16 operand, and therefore
src1 is implicitly truncated to 16 bits when lowering to that instruction from the
intrinsic. This is unlikely to result in an error in practice
because values that large are not useful.

The operand class of src1 in the True16 version of the instruction has
been corrected to encode correctly on GFX11.

Reviewed By: foad, rampitec

Differential Revision: https://reviews.llvm.org/D136195




More information about the All-commits mailing list