diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/LTO/LTO.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp index bfb8a5c76a2..654b86a0dfd 100644 --- a/llvm/lib/LTO/LTO.cpp +++ b/llvm/lib/LTO/LTO.cpp @@ -128,20 +128,25 @@ static void thinLTOResolveWeakForLinkerGUID( function_ref<void(StringRef, GlobalValue::GUID, GlobalValue::LinkageTypes)> recordNewLinkage) { for (auto &S : GVSummaryList) { - if (GlobalInvolvedWithAlias.count(S.get())) - continue; GlobalValue::LinkageTypes OriginalLinkage = S->linkage(); if (!GlobalValue::isWeakForLinker(OriginalLinkage)) continue; // We need to emit only one of these. The prevailing module will keep it, // but turned into a weak, while the others will drop it when possible. + // This is both a compile-time optimization and a correctness + // transformation. This is necessary for correctness when we have exported + // a reference - we need to convert the linkonce to weak to + // ensure a copy is kept to satisfy the exported reference. + // FIXME: We may want to split the compile time and correctness + // aspects into separate routines. if (isPrevailing(GUID, S.get())) { if (GlobalValue::isLinkOnceLinkage(OriginalLinkage)) S->setLinkage(GlobalValue::getWeakLinkage( GlobalValue::isLinkOnceODRLinkage(OriginalLinkage))); } - // Alias can't be turned into available_externally. + // Alias and aliasee can't be turned into available_externally. else if (!isa<AliasSummary>(S.get()) && + !GlobalInvolvedWithAlias.count(S.get()) && (GlobalValue::isLinkOnceODRLinkage(OriginalLinkage) || GlobalValue::isWeakODRLinkage(OriginalLinkage))) S->setLinkage(GlobalValue::AvailableExternallyLinkage); |
