refactor some code out of OPC_EmitMergeInputChains into a
new helper function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97525 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 3c5e90b..7fd2756 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -1574,7 +1574,34 @@
DEBUG(errs() << "ISEL: Match complete!\n");
}
-
+/// HandleMergeInputChains - This implements the OPC_EmitMergeInputChains
+/// operation for when the pattern matched multiple nodes with chains.
+static SDValue
+HandleMergeInputChains(const SmallVectorImpl<SDNode*> &ChainNodesMatched,
+ SelectionDAG *CurDAG) {
+ assert(ChainNodesMatched.size() > 1 &&
+ "Should only happen for multi chain node case");
+
+ // Walk all the chained nodes, adding the input chains if they are not in
+ // ChainedNodes (and this, not in the matched pattern). This is an N^2
+ // algorithm, but # chains is usually 2 here, at most 3 for MSP430.
+ SmallVector<SDValue, 3> InputChains;
+ for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
+ SDValue InChain = ChainNodesMatched[i]->getOperand(0);
+ assert(InChain.getValueType() == MVT::Other && "Not a chain");
+ bool Invalid = false;
+ for (unsigned j = 0; j != e; ++j)
+ Invalid |= ChainNodesMatched[j] == InChain.getNode();
+ if (!Invalid)
+ InputChains.push_back(InChain);
+ }
+
+ SDValue Res;
+ if (InputChains.size() == 1)
+ return InputChains[0];
+ return CurDAG->getNode(ISD::TokenFactor, ChainNodesMatched[0]->getDebugLoc(),
+ MVT::Other, &InputChains[0], InputChains.size());
+}
struct MatchScope {
/// FailIndex - If this match fails, this is the index to continue with.
@@ -2026,28 +2053,17 @@
break;
}
}
+
+ // If the inner loop broke out, the match fails.
+ if (ChainNodesMatched.empty())
+ break;
- // Walk all the chained nodes, adding the input chains if they are not in
- // ChainedNodes (and this, not in the matched pattern). This is an N^2
- // algorithm, but # chains is usually 2 here, at most 3 for MSP430.
- SmallVector<SDValue, 3> InputChains;
- for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
- SDValue InChain = ChainNodesMatched[i]->getOperand(0);
- assert(InChain.getValueType() == MVT::Other && "Not a chain");
- bool Invalid = false;
- for (unsigned j = 0; j != e; ++j)
- Invalid |= ChainNodesMatched[j] == InChain.getNode();
- if (!Invalid)
- InputChains.push_back(InChain);
- }
+ // Merge the input chains if they are not intra-pattern references.
+ InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
+
+ if (InputChain.getNode() == 0)
+ break; // Failed to merge.
- SDValue Res;
- if (InputChains.size() == 1)
- InputChain = InputChains[0];
- else
- InputChain = CurDAG->getNode(ISD::TokenFactor,
- NodeToMatch->getDebugLoc(), MVT::Other,
- &InputChains[0], InputChains.size());
continue;
}