[all-commits] [llvm/llvm-project] 255ea4: [ELF] Merge verdefIndex into versionId. NFC (#72208)

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 255ea486085fca79d21eb0082594579abdbd89d0
      https://github.com/llvm/llvm-project/commit/255ea486085fca79d21eb0082594579abdbd89d0
  Author: Fangrui Song <i at maskray.me>
  Date:   2023-11-16 (Thu, 16 Nov 2023)

  Changed paths:
    M lld/ELF/InputFiles.cpp
    M lld/ELF/Relocations.cpp
    M lld/ELF/SymbolTable.cpp
    M lld/ELF/Symbols.cpp
    M lld/ELF/Symbols.h
    M lld/ELF/SyntheticSections.cpp

  Log Message:
  -----------
  [ELF] Merge verdefIndex into versionId. NFC (#72208)

The two fields are similar.

`versionId` is the Verdef index in the output file. It is set for
`--exclude-id=`, version script patterns, and `sym at ver` symbols.

`verdefIndex` is the Verdef index of a Sharedfile (SharedSymbol or a
copy-relocated Defined), the default value -1 is also used to indicate
that the symbol has not been matched by a version script pattern
(https://reviews.llvm.org/D65716).

It seems confusing to have two fields. Merge them so that we can
allocate one bit for #70130 (suppress --no-allow-shlib-undefined
error in the presence of a DSO definition).