Nico Weber e16c0a9a68 clang+lld: Improve clang+ld.darwinnew.lld interaction, pass -demangle
This patch:
- adds an ld64.lld.darwinnew symlink for lld, to go with f2710d4b576,
  so that `clang -fuse-ld=lld.darwinnew` can be used to test new
  Mach-O lld while it's in bring-up. (The expectation is that we'll
  remove this again once new Mach-O lld is the defauld and only Mach-O
  lld.)
- lets the clang driver know if the linker is lld (currently
  only triggered if `-fuse-ld=lld` or `-fuse-ld=lld.darwinnew` is
  passed). Currently only used for the next point, but could be used
  to implement other features that need close coordination between
  compiler and linker, e.g. having a diag for calling `clang++` instead
  of `clang` when link errors are caused by a missing C++ stdlib.
- lets the clang driver pass `-demangle` to Mach-O lld (both old and
  new), in addition to ld64
- implements -demangle for new Mach-O lld
- changes demangleItanium() to accept _Z, __Z, ___Z, ____Z prefixes
  (and updates one test added in D68014). Mach-O has an extra
  underscore for symbols, and the three (or, on Mach-O, four)
  underscores are used for block names.

Differential Revision: https://reviews.llvm.org/D91884
2020-11-24 08:51:58 -05:00
..

LLVM Linker (lld)

This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.

lld is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.

Benchmarking

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