[all-commits] [llvm/llvm-project] 47b4bb: [LLD][COFF] add __buildid symbol. (#74652)

[Zequan Wu via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 47b4bbfe522cd7a9251b0a8813576ab6f0b59616
      https://github.com/llvm/llvm-project/commit/47b4bbfe522cd7a9251b0a8813576ab6f0b59616
  Author: Zequan Wu <zequanwu at google.com>
  Date:   2023-12-14 (Thu, 14 Dec 2023)

  Changed paths:
    M lld/COFF/Driver.cpp
    M lld/COFF/Symbols.h
    M lld/COFF/Writer.cpp
    M lld/docs/windows_support.rst
    A lld/test/COFF/build-id-sym.s

  Log Message:
  -----------
  [LLD][COFF] add __buildid symbol. (#74652)

After #71433, lld-link is able to always generate build id even when PDB
is not generated.

This adds the `__buildid` symbol to points to the start of 16 bytes guid
(which is after `RSDS`) and allows profile runtime to access it and dump
it to raw profile.