Revert the SelectionDAG optimization that makes
it impossible to create a MERGE_VALUES node with
only one result: sometimes it is useful to be able
to create a node with only one result out of one of
the results of a node with more than one result, for
example because the new node will eventually be used
to replace a one-result node using ReplaceAllUsesWith,
cf X86TargetLowering::ExpandFP_TO_SINT. On the other
hand, most users of MERGE_VALUES don't need this and
for them the optimization was valuable. So add a new
utility method getMergeValues for creating MERGE_VALUES
nodes which by default performs the optimization.
Change almost everywhere to use getMergeValues (and
tidy some stuff up at the same time).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52893 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Sparc/SparcISelLowering.cpp b/lib/Target/Sparc/SparcISelLowering.cpp
index 5c06174..48b4fec 100644
--- a/lib/Target/Sparc/SparcISelLowering.cpp
+++ b/lib/Target/Sparc/SparcISelLowering.cpp
@@ -450,8 +450,8 @@
ResultVals.push_back(Chain);
// Merge everything together with a MERGE_VALUES node.
- return DAG.getNode(ISD::MERGE_VALUES, Op.Val->getVTList(),
- &ResultVals[0], ResultVals.size());
+ return DAG.getMergeValues(Op.Val->getVTList(), &ResultVals[0],
+ ResultVals.size());
}
@@ -829,8 +829,7 @@
DAG.getNode(ISD::BIT_CONVERT, MVT::f64, V),
V.getValue(1)
};
- return DAG.getNode(ISD::MERGE_VALUES, DAG.getVTList(MVT::f64, MVT::Other),
- Ops, 2);
+ return DAG.getMergeValues(DAG.getVTList(MVT::f64, MVT::Other), Ops, 2);
}
static SDOperand LowerDYNAMIC_STACKALLOC(SDOperand Op, SelectionDAG &DAG) {
@@ -846,11 +845,8 @@
// to provide a register spill area.
SDOperand NewVal = DAG.getNode(ISD::ADD, MVT::i32, NewSP,
DAG.getConstant(96, MVT::i32));
- std::vector<MVT> Tys;
- Tys.push_back(MVT::i32);
- Tys.push_back(MVT::Other);
SDOperand Ops[2] = { NewVal, Chain };
- return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops, 2);
+ return DAG.getMergeValues(DAG.getVTList(MVT::i32, MVT::Other), Ops, 2);
}