SelectionDAG &DAG) const {
if (DisablePPCPreinc) return false;
+ bool isLoad = true;
SDValue Ptr;
EVT VT;
unsigned Alignment;
Ptr = ST->getBasePtr();
VT = ST->getMemoryVT();
Alignment = ST->getAlignment();
+ isLoad = false;
} else
return false;
if (VT.isVector())
return false;
- if (SelectAddressRegReg(Ptr, Offset, Base, DAG)) {
+ if (SelectAddressRegReg(Ptr, Base, Offset, DAG)) {
+
+ // Common code will reject creating a pre-inc form if the base pointer
+ // is a frame index, or if N is a store and the base pointer is either
+ // the same as or a predecessor of the value being stored. Check for
+ // those situations here, and try with swapped Base/Offset instead.
+ bool Swap = false;
+
+ if (isa<FrameIndexSDNode>(Base) || isa<RegisterSDNode>(Base))
+ Swap = true;
+ else if (!isLoad) {
+ SDValue Val = cast<StoreSDNode>(N)->getValue();
+ if (Val == Base || Base.getNode()->isPredecessorOf(Val.getNode()))
+ Swap = true;
+ }
+
+ if (Swap)
+ std::swap(Base, Offset);
+
AM = ISD::PRE_INC;
return true;
}