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Commit 80e2fc1e authored by Ben Dunbobbin's avatar Ben Dunbobbin Committed by Hans Wennborg
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[X86][ELF] Prefer lowering MC_GlobalAddress operands to .Lfoo$local for STV_DEFAULT only

This patch restricts the behaviour of referencing via .Lfoo$local
local aliases, introduced in https://reviews.llvm.org/D73230, to
STV_DEFAULT globals only.

Hidden symbols via --fvisiblity=hidden (https://gcc.gnu.org/wiki/Visibility)
is an important scenario.

Benefits:

- Improves the size of object files by using fewer STT_SECTION symbols.

- The code reads a bit better (it was not obvious to me without going
  back to the code reviews why the canBenefitFromLocalAlias function
  currently doesn't consider visibility).

- There is also a side benefit in restoring the effectiveness of the
  --wrap linker option and making the behavior of --wrap consistent
  between LTO and normal builds for references within a translation-unit.
  Note: this --wrap behavior (which is specific to LLD) should not be
  considered reliable. See comments on https://reviews.llvm.org/D73230
  for more.

Differential Revision: https://reviews.llvm.org/D85782

(cherry picked from commit 4cb016cd)
parent c2f4de35
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