Split SelectionDAGISel::IsLegalAndProfitableToFold to

[oota-llvm.git] / lib / Target / X86 / X86ISelDAGToDAG.cpp

diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 7bd935d2bb64d50d7d8dd764eeb48099a7bbb4e0..7b349f6a16fb166d59a9e39648a45e9d327f4779 100644 (file)
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -183,8 +183,9 @@ namespace {
 
     virtual void EmitFunctionEntryCode(Function &Fn, MachineFunction &MF);
 
-    virtual
-      bool IsLegalAndProfitableToFold(SDNode *N, SDNode *U, SDNode *Root) const;
+    virtual bool IsProfitableToFold(SDValue N, SDNode *U, SDNode *Root) const;
+
+    virtual bool IsLegalToFold(SDValue N, SDNode *U, SDNode *Root) const;
 
 // Include the pieces autogenerated from the target description.
 #include "X86GenDAGISel.inc"
@@ -303,11 +304,18 @@ namespace {
 }
 
 
-bool X86DAGToDAGISel::IsLegalAndProfitableToFold(SDNode *N, SDNode *U,
-                                                 SDNode *Root) const {
+bool
+X86DAGToDAGISel::IsProfitableToFold(SDValue N, SDNode *U, SDNode *Root) const {
   if (OptLevel == CodeGenOpt::None) return false;
 
-  if (U == Root)
+  if (!N.hasOneUse())
+    return false;
+
+  if (N.getOpcode() != ISD::LOAD)
+    return true;
+
+  // If N is a load, do additional profitability checks.
+  if (U == Root) {
     switch (U->getOpcode()) {
     default: break;
     case X86ISD::ADD:
@@ -354,9 +362,17 @@ bool X86DAGToDAGISel::IsLegalAndProfitableToFold(SDNode *N, SDNode *U,
       }
     }
     }
+  }
+
+  return true;
+}
+
+
+bool X86DAGToDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root) const {
+  if (OptLevel == CodeGenOpt::None) return false;
 
   // Proceed to 'generic' cycle finder code
-  return SelectionDAGISel::IsLegalAndProfitableToFold(N, U, Root);
+  return SelectionDAGISel::IsLegalToFold(N, U, Root);
 }
 
 /// MoveBelowTokenFactor - Replace TokenFactor operand with load's chain operand
@@ -1311,8 +1327,8 @@ bool X86DAGToDAGISel::SelectScalarSSELoad(SDNode *Op, SDValue Pred,
     InChain = N.getOperand(0).getValue(1);
     if (ISD::isNON_EXTLoad(InChain.getNode()) &&
         InChain.getValue(0).hasOneUse() &&
-        N.hasOneUse() &&
-        IsLegalAndProfitableToFold(N.getNode(), Pred.getNode(), Op)) {
+        IsProfitableToFold(N, Pred.getNode(), Op) &&
+        IsLegalToFold(N, Pred.getNode(), Op)) {
       LoadSDNode *LD = cast<LoadSDNode>(InChain);
       if (!SelectAddr(Op, LD->getBasePtr(), Base, Scale, Index, Disp, Segment))
         return false;
@@ -1436,8 +1452,8 @@ bool X86DAGToDAGISel::TryFoldLoad(SDNode *P, SDValue N,
                                   SDValue &Index, SDValue &Disp,
                                   SDValue &Segment) {
   if (ISD::isNON_EXTLoad(N.getNode()) &&
-      N.hasOneUse() &&
-      IsLegalAndProfitableToFold(N.getNode(), P, P))
+      IsProfitableToFold(N, P, P) &&
+      IsLegalToFold(N, P, P))
     return SelectAddr(P, N.getOperand(1), Base, Scale, Index, Disp, Segment);
   return false;
 }