move GetOrCreateFunctionComdat to Instrumentation.cpp/Instrumentation.h

Summary:
GetOrCreateFunctionComdat is currently used in SanitizerCoverage,
where it's defined. I'm planing to use it in HWASAN as well,
so moving it into a common location.
NFC

Reviewers: morehouse

Reviewed By: morehouse

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53218

llvm-svn: 344433

2 files changed, 19 insertions, 18 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/Instrumentation.cpp b/llvm/lib/Transforms/Instrumentation/Instrumentation.cpp
index 1c739c09e39..55b449ffca1 100644
--- a/llvm/lib/Transforms/Instrumentation/Instrumentation.cpp
+++ b/llvm/lib/Transforms/Instrumentation/Instrumentation.cpp
@@ -70,6 +70,21 @@ GlobalVariable *llvm::createPrivateGlobalForString(Module &M, StringRef Str,
   return GV;
 }
 
+Comdat *llvm::GetOrCreateFunctionComdat(Function &F,
+                                        const std::string &ModuleId) {
+  if (auto Comdat = F.getComdat()) return Comdat;
+  assert(F.hasName());
+  Module *M = F.getParent();
+  std::string Name = F.getName();
+  if (F.hasLocalLinkage()) {
+    if (ModuleId.empty())
+      return nullptr;
+    Name += ModuleId;
+  }
+  F.setComdat(M->getOrInsertComdat(Name));
+  return F.getComdat();
+}
+
 /// initializeInstrumentation - Initialize all passes in the TransformUtils
 /// library.
 void llvm::initializeInstrumentation(PassRegistry &Registry) {
diff --git a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
index 0bed4139518..b3450728f04 100644
--- a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
+++ b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
@@ -220,8 +220,6 @@ private:
                    MDNode::get(*C, None));
   }
 
-  Comdat *GetOrCreateFunctionComdat(Function &F);
-
   std::string getSectionName(const std::string &Section) const;
   std::string getSectionStart(const std::string &Section) const;
   std::string getSectionEnd(const std::string &Section) const;
@@ -590,28 +588,16 @@ bool SanitizerCoverageModule::runOnFunction(Function &F) {
   return true;
 }
 
-Comdat *SanitizerCoverageModule::GetOrCreateFunctionComdat(Function &F) {
-  if (auto Comdat = F.getComdat()) return Comdat;
-  if (!TargetTriple.isOSBinFormatELF()) return nullptr;
-  assert(F.hasName());
-  std::string Name = F.getName();
-  if (F.hasLocalLinkage()) {
-    if (CurModuleUniqueId.empty()) return nullptr;
-    Name += CurModuleUniqueId;
-  }
-  auto Comdat = CurModule->getOrInsertComdat(Name);
-  F.setComdat(Comdat);
-  return Comdat;
-}
-
 GlobalVariable *SanitizerCoverageModule::CreateFunctionLocalArrayInSection(
     size_t NumElements, Function &F, Type *Ty, const char *Section) {
   ArrayType *ArrayTy = ArrayType::get(Ty, NumElements);
   auto Array = new GlobalVariable(
       *CurModule, ArrayTy, false, GlobalVariable::PrivateLinkage,
       Constant::getNullValue(ArrayTy), "__sancov_gen_");
-  if (auto Comdat = GetOrCreateFunctionComdat(F))
-    Array->setComdat(Comdat);
+
+  if (TargetTriple.isOSBinFormatELF())
+    if (auto Comdat = GetOrCreateFunctionComdat(F, CurModuleUniqueId))
+      Array->setComdat(Comdat);
   Array->setSection(getSectionName(Section));
   Array->setAlignment(Ty->isPointerTy() ? DL->getPointerSize()
                                         : Ty->getPrimitiveSizeInBits() / 8);