[all-commits] [llvm/llvm-project] 773572: [CodeView] Add CodeView support for PGO debug info...

[Michael Holman via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 77357208c46a08b5b90729125236b52256209359
      https://github.com/llvm/llvm-project/commit/77357208c46a08b5b90729125236b52256209359
  Author: Michael Holman <michael.holman at microsoft.com>
  Date:   2021-04-21 (Wed, 21 Apr 2021)

  Changed paths:
    M llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
    A llvm/test/DebugInfo/COFF/pgo.ll

  Log Message:
  -----------
  [CodeView] Add CodeView support for PGO debug information

This change adds debug information about whether PGO is being used or
not.

Microsoft performance tooling (e.g. xperf, WPA) uses this information to
show whether functions are optimized with PGO or not, as well as whether
PGO information is invalid.

This information is useful for validating whether training scenarios are
providing good coverage of real world scenarios, showing if profile data
is out of date, etc.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D99994