[all-commits] [llvm/llvm-project] 0756aa: [macho] add support for emitting macho files with ...

[Alex Lorenz via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 0756aa397856d88f458c6836b24d36ca60fd1044
      https://github.com/llvm/llvm-project/commit/0756aa397856d88f458c6836b24d36ca60fd1044
  Author: Alex Lorenz <arphaman at gmail.com>
  Date:   2021-12-07 (Tue, 07 Dec 2021)

  Changed paths:
    M llvm/include/llvm/IR/Module.h
    M llvm/include/llvm/MC/MCAssembler.h
    M llvm/include/llvm/MC/MCObjectFileInfo.h
    M llvm/include/llvm/MC/MCStreamer.h
    M llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
    M llvm/lib/IR/Module.cpp
    M llvm/lib/MC/MCAsmStreamer.cpp
    M llvm/lib/MC/MCAssembler.cpp
    M llvm/lib/MC/MCMachOStreamer.cpp
    M llvm/lib/MC/MCStreamer.cpp
    M llvm/lib/MC/MachObjectWriter.cpp
    A llvm/test/MC/MachO/darwin-target-variant-reverse.ll
    A llvm/test/MC/MachO/darwin-target-variant.ll

  Log Message:
  -----------
  [macho] add support for emitting macho files with two build version load commands

This patch extends LLVM IR to add metadata that can be used to emit macho files with two build version load commands.
It utilizes "darwin.target_variant.triple" and "darwin.target_variant.SDK Version" metadata names for that,
which will be set by a future patch in clang.

MachO uses two build version load commands to represent an object file / binary that is targeting both the macOS target,
and the Mac Catalyst target. At runtime, a dynamic library that supports both targets can be loaded from either a native
macOS or a Mac Catalyst app on a macOS system. We want to add support to this to upstream to LLVM to be able to build
compiler-rt for both targets, to finish the complete support for the Mac Catalyst platform, which is right now targetable
by upstream clang, but the compiler-rt bits aren't supported because of the lack of this multiple build version support.

Differential Revision: https://reviews.llvm.org/D112189