add some helper methods, and a new TargetConstant node, which is not

subjected to folding.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22812 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 22 insertions, 4 deletions

diff --git a/include/llvm/CodeGen/SelectionDAG.h b/include/llvm/CodeGen/SelectionDAG.h
index 755cbfd3c5..bebcd1d944 100644
--- a/include/llvm/CodeGen/SelectionDAG.h
+++ b/include/llvm/CodeGen/SelectionDAG.h
@@ -94,6 +94,7 @@ public:
   void RemoveDeadNodes(SDNode *N = 0);
 
   SDOperand getConstant(uint64_t Val, MVT::ValueType VT);
+  SDOperand getTargetConstant(uint64_t Val, MVT::ValueType VT);
   SDOperand getConstantFP(double Val, MVT::ValueType VT);
   SDOperand getGlobalAddress(const GlobalValue *GV, MVT::ValueType VT);
   SDOperand getFrameIndex(int FI, MVT::ValueType VT);
@@ -226,7 +227,18 @@ public:
   void SelectNodeTo(SDNode *N, MVT::ValueType VT, unsigned TargetOpc,
                     SDOperand Op1, SDOperand Op2, SDOperand Op3);
   
-  
+  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
+                          SDOperand Op1) {
+    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1);
+  }
+  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
+                          SDOperand Op1, SDOperand Op2) {
+    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2);
+  }
+  SDOperand getTargetNode(unsigned Opcode, MVT::ValueType VT,
+                          SDOperand Op1, SDOperand Op2, SDOperand Op3) {
+    return getNode(ISD::BUILTIN_OP_END+Opcode, VT, Op1, Op2, Op3);
+  }
   void dump() const;
 
 private:
@@ -258,6 +270,7 @@ private:
 
   std::map<const GlobalValue*, SDNode*> GlobalValues;
   std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> Constants;
+  std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> TargetConstants;
   std::map<std::pair<uint64_t, MVT::ValueType>, SDNode*> ConstantFPs;
   std::map<int, SDNode*> FrameIndices;
   std::map<unsigned, SDNode*> ConstantPoolIndices;
diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index 4eecb0a6b7..00b94037ad 100644
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -56,6 +56,10 @@ namespace ISD {
     // Various leaf nodes.
     Constant, ConstantFP, GlobalAddress, FrameIndex, ConstantPool,
     BasicBlock, ExternalSymbol, VALUETYPE, CONDCODE, Register,
+    
+    // TargetConstant - Like Constant, but the DAG does not do any folding or
+    // simplification of the constant.  This is used by the DAG->DAG selector.
+    TargetConstant,
 
     // CopyToReg - This node has three operands: a chain, a register number to
     // set to this value, and a value.  
@@ -681,8 +685,8 @@ class ConstantSDNode : public SDNode {
   uint64_t Value;
 protected:
   friend class SelectionDAG;
-  ConstantSDNode(uint64_t val, MVT::ValueType VT)
-    : SDNode(ISD::Constant, VT), Value(val) {
+  ConstantSDNode(bool isTarget, uint64_t val, MVT::ValueType VT)
+    : SDNode(isTarget ? ISD::TargetConstant : ISD::Constant, VT), Value(val) {
   }
 public:
 
@@ -702,7 +706,8 @@ public:
 
   static bool classof(const ConstantSDNode *) { return true; }
   static bool classof(const SDNode *N) {
-    return N->getOpcode() == ISD::Constant;
+    return N->getOpcode() == ISD::Constant ||
+           N->getOpcode() == ISD::TargetConstant;
   }
 };