diff --git a/include/llvm/LLVMContext.h b/include/llvm/LLVMContext.h index f5916c47a0a..d74fa11f3fe 100644 --- a/include/llvm/LLVMContext.h +++ b/include/llvm/LLVMContext.h @@ -30,7 +30,7 @@ struct LLVMContextImpl; /// to have one context per thread. struct LLVMContext { LLVMContextImpl* pImpl; - + bool RemoveDeadMetadata(); LLVMContext(); ~LLVMContext(); }; diff --git a/lib/Transforms/IPO/GlobalDCE.cpp b/lib/Transforms/IPO/GlobalDCE.cpp index 8e57768570a..09f9e7c4f68 100644 --- a/lib/Transforms/IPO/GlobalDCE.cpp +++ b/lib/Transforms/IPO/GlobalDCE.cpp @@ -148,6 +148,9 @@ bool GlobalDCE::runOnModule(Module &M) { // Make sure that all memory is released AliveGlobals.clear(); + + // Remove dead metadata. + Changed |= M.getContext().RemoveDeadMetadata(); return Changed; } diff --git a/lib/VMCore/ConstantsContext.h b/lib/VMCore/ConstantsContext.h index 2868f87fa4a..f1d4b25e1bc 100644 --- a/lib/VMCore/ConstantsContext.h +++ b/lib/VMCore/ConstantsContext.h @@ -572,6 +572,7 @@ private: public: // NOTE: This function is not locked. It is the caller's responsibility // to enforce proper synchronization. + typename MapTy::iterator map_begin() { return Map.begin(); } typename MapTy::iterator map_end() { return Map.end(); } /// InsertOrGetItem - Return an iterator for the specified element. diff --git a/lib/VMCore/LLVMContext.cpp b/lib/VMCore/LLVMContext.cpp index 22882711a06..3ca1b0afca4 100644 --- a/lib/VMCore/LLVMContext.cpp +++ b/lib/VMCore/LLVMContext.cpp @@ -20,6 +20,7 @@ #include "llvm/Support/ManagedStatic.h" #include "LLVMContextImpl.h" #include +#include using namespace llvm; @@ -44,3 +45,27 @@ GetElementPtrConstantExpr::GetElementPtrConstantExpr for (unsigned i = 0, E = IdxList.size(); i != E; ++i) OperandList[i+1] = IdxList[i]; } + +bool LLVMContext::RemoveDeadMetadata() { + std::vector DeadMDNodes; + bool Changed = false; + while (1) { + + for (LLVMContextImpl::MDNodeMapTy::MapTy::iterator + I = pImpl->MDNodes.map_begin(), + E = pImpl->MDNodes.map_end(); I != E; ++I) { + const MDNode *N = cast(I->second); + if (N->use_empty()) + DeadMDNodes.push_back(N); + } + + if (DeadMDNodes.empty()) + return Changed; + + while (!DeadMDNodes.empty()) { + const MDNode *N = DeadMDNodes.back(); DeadMDNodes.pop_back(); + delete N; + } + } + return Changed; +} diff --git a/lib/VMCore/LLVMContextImpl.h b/lib/VMCore/LLVMContextImpl.h index 3d1f3b26a5c..245aa4a7043 100644 --- a/lib/VMCore/LLVMContextImpl.h +++ b/lib/VMCore/LLVMContextImpl.h @@ -105,7 +105,10 @@ struct LLVMContextImpl { ValueMap AggZeroConstants; - ValueMap, Type, MDNode, true /*largekey*/> MDNodes; + typedef ValueMap, Type, MDNode, true /*largekey*/> + MDNodeMapTy; + + MDNodeMapTy MDNodes; typedef ValueMap, ArrayType, ConstantArray, true /*largekey*/> ArrayConstantsTy;