Reapply things reverted back in 97220, with the fixed test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97228 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PIC16/PIC16ISelLowering.cpp b/lib/Target/PIC16/PIC16ISelLowering.cpp
index d2fc8db..e167bda 100644
--- a/lib/Target/PIC16/PIC16ISelLowering.cpp
+++ b/lib/Target/PIC16/PIC16ISelLowering.cpp
@@ -1527,10 +1527,24 @@
return true;
if (isDirectLoad(Op.getOperand(1))) {
- if (Op.getOperand(1).hasOneUse())
- return false;
- else
- MemOp = 1;
+ if (Op.getOperand(1).hasOneUse()) {
+ // Legal and profitable folding check uses the NodeId of DAG nodes.
+ // This NodeId is assigned by topological order. Therefore first
+ // assign topological order then perform legal and profitable check.
+ // Note:- Though this ordering is done before begining with legalization,
+ // newly added node during legalization process have NodeId=-1 (NewNode)
+ // therefore before performing any check proper ordering of the node is
+ // required.
+ DAG.AssignTopologicalOrder();
+
+ // Direct load operands are folded in binary operations. But before folding
+ // verify if this folding is legal. Fold only if it is legal otherwise
+ // convert this direct load to a separate memory operation.
+ if(ISel->IsLegalToFold(Op.getOperand(1), Op.getNode(), Op.getNode()))
+ return false;
+ else
+ MemOp = 1;
+ }
}
return true;
}