Fix the xfail I added a couple of patches back. The issue
was that we weren't properly handling the case when interior
nodes of a matched pattern become dead after updating chain
and flag uses. Now we handle this explicitly in
UpdateChainsAndFlags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97561 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 7e1ce42..68eb4cb 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -796,8 +796,11 @@
SDNode *ResNode = Select(Node);
+ // FIXME: This is pretty gross. 'Select' should be changed to not return
+ // anything at all and this code should be nuked with a tactical strike.
+
// If node should not be replaced, continue with the next one.
- if (ResNode == Node)
+ if (ResNode == Node || Node->getOpcode() == ISD::DELETED_NODE)
continue;
// Replace node.
if (ResNode)
@@ -1532,11 +1535,16 @@
/// UpdateChainsAndFlags - When a match is complete, this method updates uses of
/// interior flag and chain results to use the new flag and chain results.
-static void UpdateChainsAndFlags(SDNode *NodeToMatch, SDValue InputChain,
- const SmallVectorImpl<SDNode*> &ChainNodesMatched,
- SDValue InputFlag,
- const SmallVectorImpl<SDNode*> &FlagResultNodesMatched,
- bool isMorphNodeTo, SelectionDAG *CurDAG) {
+void SelectionDAGISel::
+UpdateChainsAndFlags(SDNode *NodeToMatch, SDValue InputChain,
+ const SmallVectorImpl<SDNode*> &ChainNodesMatched,
+ SDValue InputFlag,
+ const SmallVectorImpl<SDNode*> &FlagResultNodesMatched,
+ bool isMorphNodeTo) {
+ SmallVector<SDNode*, 4> NowDeadNodes;
+
+ ISelUpdater ISU(ISelPosition);
+
// Now that all the normal results are replaced, we replace the chain and
// flag results if present.
if (!ChainNodesMatched.empty()) {
@@ -1547,6 +1555,10 @@
for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
SDNode *ChainNode = ChainNodesMatched[i];
+ // If this node was already deleted, don't look at it.
+ if (ChainNode->getOpcode() == ISD::DELETED_NODE)
+ continue;
+
// Don't replace the results of the root node if we're doing a
// MorphNodeTo.
if (ChainNode == NodeToMatch && isMorphNodeTo)
@@ -1556,7 +1568,11 @@
if (ChainVal.getValueType() == MVT::Flag)
ChainVal = ChainVal.getValue(ChainVal->getNumValues()-2);
assert(ChainVal.getValueType() == MVT::Other && "Not a chain?");
- CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain);
+ CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain, &ISU);
+
+ // If the node became dead, delete it.
+ if (ChainNode->use_empty())
+ NowDeadNodes.push_back(ChainNode);
}
}
@@ -1566,13 +1582,25 @@
// Handle any interior nodes explicitly marked.
for (unsigned i = 0, e = FlagResultNodesMatched.size(); i != e; ++i) {
SDNode *FRN = FlagResultNodesMatched[i];
+
+ // If this node was already deleted, don't look at it.
+ if (FRN->getOpcode() == ISD::DELETED_NODE)
+ continue;
+
assert(FRN->getValueType(FRN->getNumValues()-1) == MVT::Flag &&
"Doesn't have a flag result");
CurDAG->ReplaceAllUsesOfValueWith(SDValue(FRN, FRN->getNumValues()-1),
- InputFlag);
+ InputFlag, &ISU);
+
+ // If the node became dead, delete it.
+ if (FRN->use_empty())
+ NowDeadNodes.push_back(FRN);
}
}
+ if (!NowDeadNodes.empty())
+ CurDAG->RemoveDeadNodes(NowDeadNodes, &ISU);
+
DEBUG(errs() << "ISEL: Match complete!\n");
}
@@ -2363,7 +2391,7 @@
// If the node had chain/flag results, update our notion of the current
// chain and flag.
- if (VTs.back() == MVT::Flag) {
+ if (EmitNodeInfo & OPFL_FlagOutput) {
InputFlag = SDValue(Res, VTs.size()-1);
if (EmitNodeInfo & OPFL_Chain)
InputChain = SDValue(Res, VTs.size()-2);
@@ -2392,8 +2420,8 @@
if (Opcode == OPC_MorphNodeTo) {
// Update chain and flag uses.
UpdateChainsAndFlags(NodeToMatch, InputChain, ChainNodesMatched,
- InputFlag, FlagResultNodesMatched, true, CurDAG);
- return 0;
+ InputFlag, FlagResultNodesMatched, true);
+ return Res;
}
continue;
@@ -2452,7 +2480,7 @@
// Update chain and flag uses.
UpdateChainsAndFlags(NodeToMatch, InputChain, ChainNodesMatched,
- InputFlag, FlagResultNodesMatched, false, CurDAG);
+ InputFlag, FlagResultNodesMatched, false);
assert(NodeToMatch->use_empty() &&
"Didn't replace all uses of the node?");