Summary:
Reapply r357931 with fixes to ThinLTO testcases and llvm-lto tool.
ThinLTOCodeGenerator currently does not preserve llvm.used symbols and
it can internalize them. In order to pass the necessary information to the
legacy ThinLTOCodeGenerator, the input to the code generator is
rewritten to be based on lto::InputFile.
Now ThinLTO using the legacy LTO API will requires data layout in
Module.
"internalize" thinlto action in llvm-lto is updated to run both
"promote" and "internalize" with the same configuration as
ThinLTOCodeGenerator. The old "promote" + "internalize" option does not
produce the same output as ThinLTOCodeGenerator.
This fixes: PR41236
rdar://problem/49293439
Reviewers: tejohnson, pcc, kromanova, dexonsmith
Reviewed By: tejohnson
Subscribers: ormris, bd1976llvm, mehdi_amini, inglorion, eraman, hiraditya, jkorous, dexonsmith, arphaman, dang, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60421
llvm-svn: 358601
Summary:
Allow non-ODR weak/linkonce non-prevailing copies to be marked
as available_externally in the index. Add support for dropping these to
declarations in the backend.
Reviewers: mehdi_amini, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D28806
llvm-svn: 292656
Summary:
When we have an aliasee that is linkonce, while we can't convert
the non-prevailing copies to available_externally, we still need to
convert the prevailing copy to weak. If a reference to the aliasee
is exported, not converting a copy to weak will result in undefined
references when the linkonce is removed in its original module.
Add a new test and update existing tests.
Reviewers: mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26076
llvm-svn: 285512
We currently do not touch a symbol's linkage in the case where a definition
has a single copy. However, this code is effectively unnecessary: either
the definition is not exported, in which case the internalize phase sets
its linkage to internal, or it is exported, in which case we need to promote
linkage to weak. Those two cases are already handled by existing code.
I believe that the only real functional change here is in the case where we
have a single definition which does not prevail (e.g. because the definition
in a native object file prevails). In that case we now lower linkage to
available_externally following the existing code path for that case.
As a result we can remove the isExported function parameter from the
thinLTOResolveWeakForLinkerInIndex function.
Differential Revision: http://reviews.llvm.org/D21883
llvm-svn: 274784
This tests the effect of both promotion and internalization on a module,
and helps show that D21883 is NFC wrt promotion+internalization.
Differential Revision: http://reviews.llvm.org/D21915
llvm-svn: 274699
Summary:
Ensure we keep prevailing copy of LinkOnceAny by converting it to
WeakAny.
Rename odr_resolution test to the now more appropriate weak_resolution
(weak in the linker sense includes linkonce).
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D20634
llvm-svn: 270850
