[all-commits] [llvm/llvm-project] 33acdc: [compiler-rt][xray] Fix alignment of XRayFileHeader

[Leandro Lupori via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 33acdc1e2fbf9775f73d12a0964f1866ae828052
      https://github.com/llvm/llvm-project/commit/33acdc1e2fbf9775f73d12a0964f1866ae828052
  Author: Leandro Lupori <leandro.lupori at linaro.org>
  Date:   2023-07-17 (Mon, 17 Jul 2023)

  Changed paths:
    M compiler-rt/lib/xray/xray_fdr_logging.cpp

  Log Message:
  -----------
  [compiler-rt][xray] Fix alignment of XRayFileHeader

XRayFileHeader storage was obtained from std::aligned_storage
using its default alignment and not the struct's alignment
requirement. This was causing a bus error on AArch32, on armv8
machines, where vld1.64/vst1.64 instructions with 128-bit
alignment requirement were being used to copy XRayFileHeader.

There is still another issue with fdr-single-thread.cpp test on
armv7. Now it runs until completion and produces a valid log file,
but for some reason the function name appears as _end in it,
instead of the expected mangled fn name.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D155013