[all-commits] [llvm/llvm-project] 8eb617: [SampleFDO] Allow forward compatibility when addin...

[wmi-11 via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 8eb617d719bdc6a4ed7773925d2421b9bbdd4b7a
      https://github.com/llvm/llvm-project/commit/8eb617d719bdc6a4ed7773925d2421b9bbdd4b7a
  Author: Wei Mi <wmi at google.com>
  Date:   2021-09-07 (Tue, 07 Sep 2021)

  Changed paths:
    M llvm/include/llvm/ProfileData/SampleProf.h
    M llvm/include/llvm/ProfileData/SampleProfReader.h
    A llvm/test/tools/llvm-profdata/Inputs/unknown.section.extbin.profdata
    A llvm/test/tools/llvm-profdata/forward-compatible.test

  Log Message:
  -----------
  [SampleFDO] Allow forward compatibility when adding a new section for extbinary
format.

Currently when we add a new section in the profile format and generate a profile
containing the new section, older compiler which reads the new profile will
issue an error. The forward incompatibility can cause unnecessary churn when
extending the profile. This patch removes the incompatibility when adding a new
section for extbinary format.

Differential Revision: https://reviews.llvm.org/D109398