Added a target specific hook to check whether / how a node can be transformed

into a pair of base / offset nodes for pre-indexed load / store ops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31407 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/TargetLowering.h

@@ -371,6 +371,16 @@ public:
   unsigned getJumpBufAlignment() const {
     return JumpBufAlignment;
   }
+
+  /// getLegalPreIndexedAddressBase - returns true by value, base pointer and
+  /// offset pointer and addressing mode by reference if the node's address
+  /// can be legally represented as pre-indexed load / store address.
+  virtual bool getLegalPreIndexedAddressBase(SDNode *N, SDOperand &Base,
+                                             SDOperand &Offset,
+                                             ISD::MemOpAddrMode &AM,
+                                             SelectionDAG &DAG) {
+    return false;
+  }
   
   //===--------------------------------------------------------------------===//
   // TargetLowering Optimization Methods