On X86, MEMBARRIER, MFENCE, SFENCE, LFENCE are not target memory intrinsics,
so don't claim they are.  They are allocated using DAG.getNode, so attempts
to access MemSDNode fields results in reading off the end of the allocated
memory.  This fixes crashes with "llc -debug" due to debug code trying to
print MemSDNode fields for these barrier nodes (since the crashes are not
deterministic, use valgrind to see this).  Add some nasty checking to try
to catch this kind of thing in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119901 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 82a1746..63f998a 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -745,8 +745,8 @@
   return Node;
 }
 
-/// VerifyNode - Sanity check the given node.  Aborts if it is invalid.
-void SelectionDAG::VerifyNode(SDNode *N) {
+/// VerifyNodeCommon - Sanity check the given node.  Aborts if it is invalid.
+static void VerifyNodeCommon(SDNode *N) {
   switch (N->getOpcode()) {
   default:
     break;
@@ -780,6 +780,43 @@
   }
 }
 
+/// VerifySDNode - Sanity check the given SDNode.  Aborts if it is invalid.
+static void VerifySDNode(SDNode *N) {
+  // The SDNode allocators cannot be used to allocate nodes with fields that are
+  // not present in an SDNode!
+  assert(!isa<MemSDNode>(N) && "Bad MemSDNode!");
+  assert(!isa<ShuffleVectorSDNode>(N) && "Bad ShuffleVectorSDNode!");
+  assert(!isa<ConstantSDNode>(N) && "Bad ConstantSDNode!");
+  assert(!isa<ConstantFPSDNode>(N) && "Bad ConstantFPSDNode!");
+  assert(!isa<GlobalAddressSDNode>(N) && "Bad GlobalAddressSDNode!");
+  assert(!isa<FrameIndexSDNode>(N) && "Bad FrameIndexSDNode!");
+  assert(!isa<JumpTableSDNode>(N) && "Bad JumpTableSDNode!");
+  assert(!isa<ConstantPoolSDNode>(N) && "Bad ConstantPoolSDNode!");
+  assert(!isa<BasicBlockSDNode>(N) && "Bad BasicBlockSDNode!");
+  assert(!isa<SrcValueSDNode>(N) && "Bad SrcValueSDNode!");
+  assert(!isa<MDNodeSDNode>(N) && "Bad MDNodeSDNode!");
+  assert(!isa<RegisterSDNode>(N) && "Bad RegisterSDNode!");
+  assert(!isa<BlockAddressSDNode>(N) && "Bad BlockAddressSDNode!");
+  assert(!isa<EHLabelSDNode>(N) && "Bad EHLabelSDNode!");
+  assert(!isa<ExternalSymbolSDNode>(N) && "Bad ExternalSymbolSDNode!");
+  assert(!isa<CondCodeSDNode>(N) && "Bad CondCodeSDNode!");
+  assert(!isa<CvtRndSatSDNode>(N) && "Bad CvtRndSatSDNode!");
+  assert(!isa<VTSDNode>(N) && "Bad VTSDNode!");
+  assert(!isa<MachineSDNode>(N) && "Bad MachineSDNode!");
+
+  VerifyNodeCommon(N);
+}
+
+/// VerifyMachineNode - Sanity check the given MachineNode.  Aborts if it is
+/// invalid.
+static void VerifyMachineNode(SDNode *N) {
+  // The MachineNode allocators cannot be used to allocate nodes with fields
+  // that are not present in a MachineNode!
+  // Currently there are no such nodes.
+
+  VerifyNodeCommon(N);
+}
+
 /// getEVTAlignment - Compute the default alignment value for the
 /// given type.
 ///
@@ -2297,7 +2334,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -2537,7 +2574,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -2979,7 +3016,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -3047,7 +3084,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -4211,7 +4248,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -4293,7 +4330,7 @@
   }
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifySDNode(N);
 #endif
   return SDValue(N, 0);
 }
@@ -4901,7 +4938,7 @@
 
   AllNodes.push_back(N);
 #ifndef NDEBUG
-  VerifyNode(N);
+  VerifyMachineNode(N);
 #endif
   return N;
 }