[PATCH] D39079: New clang option -fno-plt to avoid PLT for external calls
Sriraman Tallam via cfe-commits
cfe-commits at lists.llvm.org
Tue Oct 24 10:31:19 PDT 2017
On Tue, Oct 24, 2017 at 10:25 AM, Joerg Sonnenberger via Phabricator
<reviews at reviews.llvm.org> wrote:
> joerg added a comment.
> Let me phrase it differently. What is this patch (and the matching backend PR) supposed to achieve? There are effectively two ways to get rid of PLT entries:
> (1) Bind references locally. This is effectively what -Bsymbolic does and what is breaking the ELF interposition rules.
> (2) Do an indirect call via the GOT. Requires knowing what an external symbol is, making it non-attractive for anything but LTO, since it will create performance issues for all non-local accesses (i.e. anything private).
With regards to performance issues, are you saying this knowing that
GOLD and BFD linkers (lld patch will follow) can convert the indirect
calls to direct? GOLD discussion here:
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