From 83e82266b6c3eeea01912df35133c06effe7ccec Mon Sep 17 00:00:00 2001 From: dim Date: Wed, 12 Nov 2014 20:01:10 +0000 Subject: [PATCH] =?UTF-8?q?=EF=BB=BFPull=20in=20r221709=20from=20upstream?= =?UTF-8?q?=20llvm=20trunk=20(by=20Fr=C3=A9d=C3=A9ric=20Riss):?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Totally forget deallocated SDNodes in SDDbgInfo. What would happen before that commit is that the SDDbgValues associated with a deallocated SDNode would be marked Invalidated, but SDDbgInfo would keep a map entry keyed by the SDNode pointer pointing to this list of invalidated SDDbgNodes. As the memory gets reused, the list might get wrongly associated with another new SDNode. As the SDDbgValues are cloned when they are transfered, this can lead to an exponential number of SDDbgValues being produced during DAGCombine like in http://llvm.org/bugs/show_bug.cgi?id=20893 Note that the previous behavior wasn't really buggy as the invalidation made sure that the SDDbgValues won't be used. This commit can be considered a memory optimization and as such is really hard to validate in a unit-test. This should fix abnormally large memory usage and resulting OOM crashes when compiling certain ports with debug information. Reported by: Dmitry Marakasov Upstream PRs: http://llvm.org/PR19031 http://llvm.org/PR20893 MFC after: 1 week --- contrib/llvm/include/llvm/CodeGen/SelectionDAG.h | 4 ++++ .../lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 16 ++++++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-) diff --git a/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h b/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h index 82becca315a1..9e1115b117ce 100644 --- a/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h +++ b/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h @@ -127,6 +127,10 @@ class SDDbgInfo { DbgValMap[Node].push_back(V); } + /// \brief Invalidate all DbgValues attached to the node and remove + /// it from the Node-to-DbgValues map. + void erase(const SDNode *Node); + void clear() { DbgValMap.clear(); DbgValues.clear(); diff --git a/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 45d5a4fa69e8..a702bee3d687 100644 --- a/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -625,6 +625,15 @@ void SelectionDAG::DeleteNodeNotInCSEMaps(SDNode *N) { DeallocateNode(N); } +void SDDbgInfo::erase(const SDNode *Node) { + DbgValMapType::iterator I = DbgValMap.find(Node); + if (I == DbgValMap.end()) + return; + for (auto &Val: I->second) + Val->setIsInvalidated(); + DbgValMap.erase(I); +} + void SelectionDAG::DeallocateNode(SDNode *N) { if (N->OperandsNeedDelete) delete[] N->OperandList; @@ -635,10 +644,9 @@ void SelectionDAG::DeallocateNode(SDNode *N) { NodeAllocator.Deallocate(AllNodes.remove(N)); - // If any of the SDDbgValue nodes refer to this SDNode, invalidate them. - ArrayRef DbgVals = DbgInfo->getSDDbgValues(N); - for (unsigned i = 0, e = DbgVals.size(); i != e; ++i) - DbgVals[i]->setIsInvalidated(); + // If any of the SDDbgValue nodes refer to this SDNode, invalidate + // them and forget about that node. + DbgInfo->erase(N); } /// RemoveNodeFromCSEMaps - Take the specified node out of the CSE map that