2020 08 03 sync

Agenda

• Opens

• Patches in review for llorg:

  • https://reviews.llvm.org/D80932 - [SYCL] Make default address space a superset of OpenCL address spaces

• GitHub issues/PRs

  • https://github.com/intel/llvm/issues/2041 - [SYCL][FE] Add an attribute to annotate special sycl types
    • https://reviews.llvm.org/D71016 - [SYCL] Implement OpenCL kernel function generation
  • Enabling standard optimizations for SPIR target
    • "Dead" kernel arguments optimization
  • https://github.com/intel/llvm/issues/1799#issuecomment-637395726 - half implementation: __fp16 vs _Float16.

• Back-burner

  • https://reviews.llvm.org/D77220 - [SYCL] Enable OpenCL types required for implementing the SYCL headers.

Meeting notes

Participants: Alexey Bader (Intel), Mariya Podchischaeva (Intel), Roland Schulz (Intel), Ronan Keryell (Xilinx), Michael Wong (Codeplay),

• https://reviews.llvm.org/D80932 - [SYCL] Make default address space a superset of OpenCL address spaces.

  • Alexey: The discussion on cfe-dev mailing list is in progress.
  • Alexey: John McCall and David Rector seems to be okay with the proposed approach of using attributes for explicit address space annotation and avoid implicit annotation in AST.
  • Alexey: I'll check with Anastasia if she still have concerns about re-using OpenCL attributes this way. If so, we will add SYCL-specific attributes.

• https://github.com/intel/llvm/issues/2041 - [SYCL][FE] Add an attribute to annotate special sycl types

  • https://reviews.llvm.org/D71016 - [SYCL] Implement OpenCL kernel function generation
  • Mariya: Still working on implementation for sycl_special_type attribute.

• Enabling standard optimizations for SPIR target

  • Alexey: I've created a https://github.com/intel/llvm/pull/2207 to gather data on issues exposed by enabling standard optimization pipeline for SYCL device code.
  • Alexey: We also started working on SYCL-specific optimization removing "dead" SYCL kernel arguments
  • Alexey: Relevant patches:
    • https://github.com/intel/llvm/pull/2236: Adds a table to SYCL integration header with kernel arg optimization table to mark kernel parameters that can be omitted.
    • https://github.com/intel/llvm/pull/2226: LLVM pass analyzing kernel arguments and updating SYCL integration header.
    • There should be a couple of other patches improving SYCL runtime and compiler driver.

• https://github.com/intel/llvm/issues/1799#issuecomment-637395726 - half implementation: __fp16 vs _Float16.

  • Alexey: I wanted to check with Victor if he had a chance to try switching half implementation from _Float16 to __fp16. Let's keep for the next meeting.

• https://reviews.llvm.org/D77220 - [SYCL] Enable OpenCL types required for implementing the SYCL headers.

  • Alexey: this patch is adds support for SYCL special types like image/sampler. CodeGen test for this patch depends on https://reviews.llvm.org/D71016.