[all-commits] [llvm/llvm-project] d1762f: [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: d1762fc454c0d7ee0bcffe87e798f67b6c43c1d2
      https://github.com/llvm/llvm-project/commit/d1762fc454c0d7ee0bcffe87e798f67b6c43c1d2
  Author: Mariusz Sikora <mariusz.sikora at amd.com>
  Date:   2022-04-25 (Mon, 25 Apr 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