[all-commits] [llvm/llvm-project] 589897: BPF: support inlining __builtin_memcmp intrinsic call

[yonghong-song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5898979387bc4b0a6cddbeacac4a06c1d54933a9
      https://github.com/llvm/llvm-project/commit/5898979387bc4b0a6cddbeacac4a06c1d54933a9
  Author: Yonghong Song <yhs at fb.com>
  Date:   2022-03-29 (Tue, 29 Mar 2022)

  Changed paths:
    M llvm/lib/Target/BPF/BPFISelLowering.cpp
    M llvm/lib/Target/BPF/BPFTargetTransformInfo.h
    A llvm/test/CodeGen/BPF/memcmp.ll

  Log Message:
  -----------
  BPF: support inlining __builtin_memcmp intrinsic call

Delyan Kratunov reported an issue where __builtin_memcmp is
not inlined into simple load/compare instructions.
This is a known issue. In the current state, __builtin_memcmp
will be converted to memcmp call which won't work for
bpf programs.

This patch added support for expanding __builtin_memcmp with
actual loads and compares up to currently maximum 128 total loads.
The implementation is identical to PowerPC.

Differential Revision: https://reviews.llvm.org/D122676