[all-commits] [llvm/llvm-project] 2417de: [AMDGPU] Use d16 flag for image.sample instructions

[Mariusz Sikora via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2417de2758c306c5509782400ba9e0bb70851989
      https://github.com/llvm/llvm-project/commit/2417de2758c306c5509782400ba9e0bb70851989
  Author: Mariusz Sikora <mariusz.sikora at amd.com>
  Date:   2022-05-05 (Thu, 05 May 2022)

  Changed paths:
    M llvm/lib/Target/AMDGPU/AMDGPUInstCombineIntrinsic.cpp
    A llvm/test/Transforms/InstCombine/AMDGPU/image-d16.ll

  Log Message:
  -----------
  [AMDGPU] Use d16 flag for image.sample instructions

Image.sample instruction can be forced to return half type instead of
float when d16 flag is enabled.

This patch adds new pattern in InstCombine to detect if output of
image.sample is used later only by fptrunc which converts the type
from float to half. If pattern is detected then fptrunc and image.sample
are combined to single image.sample which is returning half type.
Later in Lowering part d16 flag is added to image sample intrinsic.

Differential Revision: https://reviews.llvm.org/D124232