[all-commits] [llvm/llvm-project] 43b133: [ELF] Add internal InputFile (#78944)

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 43b13341fbbb718223484a79a539a3c13062f39f
      https://github.com/llvm/llvm-project/commit/43b13341fbbb718223484a79a539a3c13062f39f
  Author: Fangrui Song <i at maskray.me>
  Date:   2024-01-22 (Mon, 22 Jan 2024)

  Changed paths:
    M lld/ELF/Arch/ARM.cpp
    M lld/ELF/Arch/Mips.cpp
    M lld/ELF/Arch/PPC64.cpp
    M lld/ELF/Config.h
    M lld/ELF/Driver.cpp
    M lld/ELF/InputFiles.cpp
    M lld/ELF/InputFiles.h
    M lld/ELF/InputSection.cpp
    M lld/ELF/InputSection.h
    M lld/ELF/LTO.cpp
    M lld/ELF/LinkerScript.cpp
    M lld/ELF/Relocations.cpp
    M lld/ELF/ScriptLexer.h
    M lld/ELF/ScriptParser.cpp
    M lld/ELF/SyntheticSections.cpp
    M lld/ELF/Target.cpp
    M lld/ELF/Writer.cpp
    M lld/test/ELF/cref.s
    M lld/test/ELF/linkerscript/symbol-ordering-file2.s
    M lld/test/ELF/x86-64-gotpc-no-relax-err.s

  Log Message:
  -----------
  [ELF] Add internal InputFile (#78944)

Based on https://reviews.llvm.org/D45375 . Introduce a new InputFile
kind `InternalKind`, use it for

* `ctx.internalFile`: for linker-defined symbols and some synthesized
`Undefined`
* `createInternalFile`: for symbol assignments and --defsym

I picked "internal" instead of "synthetic" to avoid confusion with
SyntheticSection.

Currently a symbol's file is one of: nullptr, ObjKind, SharedKind,
BitcodeKind, BinaryKind. Now it's non-null (I plan to add an
`assert(file)` to Symbol::Symbol and change `toString(const InputFile
*)`
separately).

Debugging and error reporting gets improved. The immediate user-facing
difference is more descriptive "File" column in the --cref output. This
patch may unlock further simplification.

Currently each symbol assignment gets its own
`createInternalFile(cmd->location)`. Two symbol assignments in a linker
script do not share the same file. Making the file the same would be
nice, but would require non trivial code.