[all-commits] [llvm/llvm-project] da0e5b: [ELF] Refactor -z combreloc

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: da0e5b885b25cf4ded0fa89b965dc6979ac02ca9
      https://github.com/llvm/llvm-project/commit/da0e5b885b25cf4ded0fa89b965dc6979ac02ca9
  Author: Fangrui Song <i at maskray.me>
  Date:   2022-01-29 (Sat, 29 Jan 2022)

  Changed paths:
    M lld/ELF/SyntheticSections.cpp
    M lld/ELF/SyntheticSections.h
    M lld/ELF/Writer.cpp
    M lld/test/ELF/pack-dyn-relocs.s

  Log Message:
  -----------
  [ELF] Refactor -z combreloc

* `RelocationBaseSection::addReloc` increases `numRelativeRelocs`, which
  duplicates the work done by RelocationSection<ELFT>::writeTo.
* --pack-dyn-relocs=android has inappropropriate DT_RELACOUNT.
  AndroidPackedRelocationSection does not necessarily place relative relocations
  in the front and DT_RELACOUNT might cause semantics error (though our
  implementation doesn't and Android bionic doesn't use DT_RELACOUNT anyway.)

Move `llvm::partition` to a new function `partitionRels` and compute
`numRelativeRelocs` there. Now `RelocationBaseSection::addReloc` is trivial and
can be moved to the header to enable inlining.

The rest of DynamicReloc and `-z combreloc` handling is moved to the
non-template `RelocationBaseSection::computeRels` to decrease code size. My
x86-64 lld executable is 44+KiB smaller.

While here, rename `sort` to `combreloc`.