diff options
| -rw-r--r-- | llvm/lib/Transforms/IPO/FunctionImport.cpp | 9 | ||||
| -rw-r--r-- | llvm/test/ThinLTO/X86/Inputs/linkonce_resolution_comdat.ll | 13 | ||||
| -rw-r--r-- | llvm/test/ThinLTO/X86/linkonce_resolution_comdat.ll | 23 |
3 files changed, 45 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp index c9d008ebd38..4b429d88215 100644 --- a/llvm/lib/Transforms/IPO/FunctionImport.cpp +++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp @@ -493,6 +493,15 @@ void llvm::thinLTOResolveWeakForLinkerModule( DEBUG(dbgs() << "ODR fixing up linkage for `" << GV.getName() << "` from " << GV.getLinkage() << " to " << NewLinkage << "\n"); GV.setLinkage(NewLinkage); + // Remove functions converted to available_externally from comdats, + // as this is a declaration for the linker, and will be dropped eventually. + // It is illegal for comdats to contain declarations. + auto *GO = dyn_cast_or_null<GlobalObject>(&GV); + if (GO && GO->isDeclarationForLinker() && GO->hasComdat()) { + assert(GO->hasAvailableExternallyLinkage() && + "Expected comdat on definition (possibly available external)"); + GO->setComdat(nullptr); + } }; // Process functions and global now diff --git a/llvm/test/ThinLTO/X86/Inputs/linkonce_resolution_comdat.ll b/llvm/test/ThinLTO/X86/Inputs/linkonce_resolution_comdat.ll new file mode 100644 index 00000000000..59434a81986 --- /dev/null +++ b/llvm/test/ThinLTO/X86/Inputs/linkonce_resolution_comdat.ll @@ -0,0 +1,13 @@ +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +$c2 = comdat any + +define linkonce_odr i32 @f(i8*) unnamed_addr comdat($c2) { + ret i32 41 +} + +define i32 @g() { + %i = call i32 @f(i8* null) + ret i32 %i +} diff --git a/llvm/test/ThinLTO/X86/linkonce_resolution_comdat.ll b/llvm/test/ThinLTO/X86/linkonce_resolution_comdat.ll new file mode 100644 index 00000000000..689ea68f3e4 --- /dev/null +++ b/llvm/test/ThinLTO/X86/linkonce_resolution_comdat.ll @@ -0,0 +1,23 @@ +; This test ensures that we drop the preempted copy of @f from %t2.bc from its +; comdat after making it available_externally. If not we would get a +; verification error. +; RUN: opt -module-summary %s -o %t1.bc +; RUN: opt -module-summary %p/Inputs/linkonce_resolution_comdat.ll -o %t2.bc +; RUN: llvm-lto -thinlto-action=run %t1.bc %t2.bc -exported-symbol=f -exported-symbol=g -disable-inlining + +; RUN: llvm-nm -o - < %t1.bc.thinlto.o | FileCheck %s --check-prefix=NM1 +; NM1: W f + +; RUN: llvm-nm -o - < %t2.bc.thinlto.o | FileCheck %s --check-prefix=NM2 +; f() would have been turned into available_externally since it is preempted, +; and inlined into g() +; NM2-NOT: f + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +$c1 = comdat any + +define linkonce_odr i32 @f(i8*) unnamed_addr comdat($c1) { + ret i32 43 +} |
