[all-commits] [llvm/llvm-project] 68745a: [InstrProfiling] Use llvm.compiler.used if applica...

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 68745a557e9454c0f54011b9eea139f04b699b69
      https://github.com/llvm/llvm-project/commit/68745a557e9454c0f54011b9eea139f04b699b69
  Author: Fangrui Song <i at maskray.me>
  Date:   2021-09-01 (Wed, 01 Sep 2021)

  Changed paths:
    A compiler-rt/test/profile/Darwin/coverage-linkage.cpp
    A compiler-rt/test/profile/Darwin/lit.local.cfg.py
    M llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
    M llvm/test/Instrumentation/InstrProfiling/profiling.ll

  Log Message:
  -----------
  [InstrProfiling] Use llvm.compiler.used if applicable for Mach-O

Similar to D97585.

D25456 used `S_ATTR_LIVE_SUPPORT` to ensure the data variable will be retained
or discarded as a unit with the counter variable, so llvm.compiler.used is
sufficient. It allows ld to dead strip unneeded profc and profd variables.

Reviewed By: vsk

Differential Revision: https://reviews.llvm.org/D105445