core changes for varargs

llvm-svn: 22254
diff --git a/llvm/lib/Target/X86/X86ISelPattern.cpp b/llvm/lib/Target/X86/X86ISelPattern.cpp
index 8ffcc82..d28de28 100644
--- a/llvm/lib/Target/X86/X86ISelPattern.cpp
+++ b/llvm/lib/Target/X86/X86ISelPattern.cpp
@@ -176,12 +176,16 @@
                 SelectionDAG &DAG);
 
     virtual std::pair<SDOperand, SDOperand>
-    LowerVAStart(SDOperand Chain, SelectionDAG &DAG);
+    LowerVAStart(SDOperand Chain, SelectionDAG &DAG, SDOperand Dest);
 
     virtual std::pair<SDOperand,SDOperand>
-    LowerVAArgNext(bool isVANext, SDOperand Chain, SDOperand VAList,
+    LowerVAArgNext(SDOperand Chain, SDOperand VAList,
                    const Type *ArgTy, SelectionDAG &DAG);
 
+    virtual std::pair<SDOperand,SDOperand>
+    LowerVACopy(SDOperand Chain, SDOperand Src, SDOperand Dest, 
+                SelectionDAG &DAG);
+
     virtual std::pair<SDOperand, SDOperand>
     LowerFrameReturnAddress(bool isFrameAddr, SDOperand Chain, unsigned Depth,
                             SelectionDAG &DAG);
@@ -442,35 +446,44 @@
   return std::make_pair(ResultVal, Chain);
 }
 
-std::pair<SDOperand, SDOperand>
-X86TargetLowering::LowerVAStart(SDOperand Chain, SelectionDAG &DAG) {
-  // vastart just returns the address of the VarArgsFrameIndex slot.
-  return std::make_pair(DAG.getFrameIndex(VarArgsFrameIndex, MVT::i32), Chain);
+std::pair<SDOperand,SDOperand> 
+X86TargetLowering::LowerVAStart(SDOperand Chain, SelectionDAG &DAG, SDOperand Dest) {
+  // vastart just stores the address of the VarArgsFrameIndex slot.
+  SDOperand FR = DAG.getFrameIndex(VarArgsFrameIndex, MVT::i32);
+  SDOperand Result = DAG.getNode(ISD::STORE, MVT::Other, Chain, FR, Dest, DAG.getSrcValue(NULL));
+  return std::make_pair(Result, Result);
 }
 
-std::pair<SDOperand,SDOperand> X86TargetLowering::
-LowerVAArgNext(bool isVANext, SDOperand Chain, SDOperand VAList,
-               const Type *ArgTy, SelectionDAG &DAG) {
+std::pair<SDOperand,SDOperand> 
+X86TargetLowering::LowerVAArgNext(SDOperand Chain, SDOperand VAList,
+                                  const Type *ArgTy, SelectionDAG &DAG) {
   MVT::ValueType ArgVT = getValueType(ArgTy);
-  SDOperand Result;
-  if (!isVANext) {
-    Result = DAG.getLoad(ArgVT, DAG.getEntryNode(), VAList,
-                         DAG.getSrcValue(NULL));
-  } else {
-    unsigned Amt;
-    if (ArgVT == MVT::i32)
-      Amt = 4;
-    else {
-      assert((ArgVT == MVT::i64 || ArgVT == MVT::f64) &&
-             "Other types should have been promoted for varargs!");
-      Amt = 8;
-    }
-    Result = DAG.getNode(ISD::ADD, VAList.getValueType(), VAList,
-                         DAG.getConstant(Amt, VAList.getValueType()));
+  SDOperand Val = DAG.getLoad(MVT::i32, Chain, VAList, DAG.getSrcValue(NULL));
+  SDOperand Result = DAG.getLoad(ArgVT, Val.getValue(1), Val, DAG.getSrcValue(NULL));
+  unsigned Amt;
+  if (ArgVT == MVT::i32)
+    Amt = 4;
+  else {
+    assert((ArgVT == MVT::i64 || ArgVT == MVT::f64) &&
+           "Other types should have been promoted for varargs!");
+    Amt = 8;
   }
+  Val = DAG.getNode(ISD::ADD, Val.getValueType(), Val,
+                    DAG.getConstant(Amt, Val.getValueType()));
+  Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain,
+                      Val, VAList, DAG.getSrcValue(NULL));
   return std::make_pair(Result, Chain);
 }
 
+std::pair<SDOperand,SDOperand>
+X86TargetLowering::LowerVACopy(SDOperand Chain, SDOperand Src, 
+                               SDOperand Dest, SelectionDAG &DAG)
+{
+  SDOperand Result = DAG.getNode(ISD::STORE, MVT::Other, Chain,
+                                 Src, Dest, DAG.getSrcValue(NULL));
+  return std::make_pair(Result, Result);
+}
+
 //===----------------------------------------------------------------------===//
 //                    Fast Calling Convention implementation
 //===----------------------------------------------------------------------===//