From 91987b5c3c398b2e8d59b3ed6b56b0aa2a3fecb4 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 19 Dec 2005 22:21:21 +0000 Subject: [PATCH] Fix a case where the DAG Combiner would accidentally CSE flag-producing nodes, creating graphs that cannot be scheduled. llvm-svn: 24866 --- lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 2fe1b0df0de..86ad89e958d 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -389,9 +389,14 @@ SDNode *SelectionDAG::AddNonLeafNodeToCSEMaps(SDNode *N) { assert(N->getNumOperands() && "This is a leaf node!"); if (N->getOpcode() == ISD::CALLSEQ_START || N->getOpcode() == ISD::CALLSEQ_END || - N->getOpcode() == ISD::HANDLENODE) + N->getOpcode() == ISD::HANDLENODE || N->getValueType(0) == MVT::Flag) return 0; // Never add these nodes. + // Check that remaining values produced are not flags. + for (unsigned i = 1, e = N->getNumValues(); i != e; ++i) + if (N->getValueType(i) == MVT::Flag) + return 0; // Never CSE anything that produces a flag. + if (N->getNumValues() == 1) { if (N->getNumOperands() == 1) { SDNode *&U = UnaryOps[std::make_pair(N->getOpcode(),