[all-commits] [llvm/llvm-project] 3cfaea: Reland "[pgo] Avoid introducing relocations by usi...

[Paul Kirth via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3cfaea2d499970c2fd14389ade59f792156be0f8
      https://github.com/llvm/llvm-project/commit/3cfaea2d499970c2fd14389ade59f792156be0f8
  Author: Paul Kirth <paulkirth at google.com>
  Date:   2022-12-08 (Thu, 08 Dec 2022)

  Changed paths:
    A compiler-rt/test/profile/instrprof-discarded-comdat.cpp
    M llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
    M llvm/test/Transforms/PGOProfile/comdat.ll
    A llvm/test/Transforms/PGOProfile/prof_avoid_relocs.ll

  Log Message:
  -----------
  Reland "[pgo] Avoid introducing relocations by using private alias"

In many cases, we can use an alias to avoid a symbolic relocations,
instead of using the public, interposable symbol. When the instrumented
function is in a COMDAT, we can use a hidden alias, and still avoid
references to discarded sections.

This disables the failing runtime test on Windows, since the compiler
options (-fPIC) are unsupported on that platform.

Reviewed By: phosek

Differential Revision: https://reviews.llvm.org/D137982