From 98b4cf8fcaf391794de17bb10bea1ec03bc0133a Mon Sep 17 00:00:00 2001 From: Diego Novillo Date: Wed, 27 May 2015 16:44:47 +0000 Subject: [PATCH] Fix PR 23499 - Avoid multiple profile counters for functions in comdat sections. Counter symbols created for linkonce functions are not discarded by ELF linkers unless the symbols are placed in the same comdat section as its associated function. llvm-svn: 238335 --- llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp index 0718ddcb6ec7..610ff52ba9db 100644 --- a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp +++ b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp @@ -203,6 +203,7 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) { uint64_t NumCounters = Inc->getNumCounters()->getZExtValue(); LLVMContext &Ctx = M->getContext(); ArrayType *CounterTy = ArrayType::get(Type::getInt64Ty(Ctx), NumCounters); + Function *Fn = Inc->getParent()->getParent(); // Create the counters variable. auto *Counters = new GlobalVariable(*M, CounterTy, false, Name->getLinkage(), @@ -211,6 +212,10 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) { Counters->setVisibility(Name->getVisibility()); Counters->setSection(getCountersSection()); Counters->setAlignment(8); + // Place the counters in the same comdat section as its parent function. + // Otherwise, we may get multiple counters for the same function in certain + // cases. + Counters->setComdat(Fn->getComdat()); RegionCounters[Inc->getName()] = Counters; @@ -235,6 +240,7 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) { Data->setVisibility(Name->getVisibility()); Data->setSection(getDataSection()); Data->setAlignment(8); + Data->setComdat(Fn->getComdat()); // Mark the data variable as used so that it isn't stripped out. UsedVars.push_back(Data);