From 02b10347bb2497e18d3a4019beed2974aa715cd4 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Sat, 22 Aug 2009 06:32:36 +0000 Subject: [PATCH] Reapply r79708 with the appropriate fix for the case that still requires locking. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79731 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 72f21125263..6ce30f6864b 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -5022,12 +5022,16 @@ static ManagedStatic > VTMutex; /// getValueTypeList - Return a pointer to the specified value type. /// const EVT *SDNode::getValueTypeList(EVT VT) { - sys::SmartScopedLock Lock(*VTMutex); if (VT.isExtended()) { + sys::SmartScopedLock Lock(*VTMutex); return &(*EVTs->insert(VT).first); } else { + // All writes to this location will have the same value, so it's ok + // to race on it. We only need to ensure that at least one write has + // succeeded before we return the pointer into the array. VTs[VT.getSimpleVT().SimpleTy] = VT; - return &VTs[VT.getSimpleVT().SimpleTy]; + sys::MemoryFence(); + return VTs + VT.getSimpleVT().SimpleTy; } }