[PATCH] D151025: [llvm-exegesis] Add support for using memory annotations

Wed Jun 28 14:56:59 PDT 2023

MaskRay added a comment.

In D151025#4455327 <https://reviews.llvm.org/D151025#4455327>, @foad wrote:

> @aidengrossman the two new lit tests are consistently failing on my machine, which is Ubuntu 22.04.2 but with kernel version 6.3.7. I get:
>
>   $ /home/jayfoad2/llvm-release/bin/llvm-exegesis -mtriple=x86_64-unknown-unknown -mode=latency -snippets-file=/home/jayfoad2/git/llvm-project/llvm/test/tools/llvm-exegesis/X86/latency/memory-annotations.s -execution-mode=subprocess
>   ---
>   mode:            latency
>   key:
>     instructions:
>       - 'MOV64ri32 RAX i_0x2000'
>       - 'MOV64rm RDI RAX i_0x1 %noreg i_0x0 %noreg'
>     config:          ''
>     register_initial_values: []
>   cpu_name:        znver4
>   llvm_triple:     x86_64-unknown-unknown
>   num_repetitions: 10000
>   measurements:    []
>   error:           'The benchmarking subprocess sent unexpected signal: Segmentation fault'
>   info:            ''
>   assembled_snippet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
>   ...
>
> I've tried running this under `lldb` but I can't catch the segfault, even if I use `settings set target.process.follow-fork-mode child`.
>
> Any ideas what might be going wrong or how to debug it?

`llvm-exegesis -mode=latency -snippets-file=memory-annotations-livein.s -execution-mode=subprocess` has this `'The benchmarking subprocess sent unexpected signal: Segmentation fault'` for me as well, but I haven't looked closely.
(`sudo apt install libpfm4-dev` so that LLVM_ENABLE_LIBPFM links the dependency)

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D151025/new/

https://reviews.llvm.org/D151025