4 files changed, 45 insertions, 4 deletions

diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index 66be26c..d84f882 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -419,6 +419,30 @@ private:
   void AddRegOperandsToUseLists(MachineRegisterInfo &RegInfo);
 };
 
+/// MachineInstrExpressionTrait - Special DenseMapInfo traits to compare
+/// MachineInstr* by *value* of the instruction rather than by pointer value.
+/// The hashing and equality testing functions ignore definitions so this is
+/// useful for CSE, etc.
+struct MachineInstrExpressionTrait : DenseMapInfo<MachineInstr*> {
+  static inline MachineInstr *getEmptyKey() {
+    return 0;
+  }
+
+  static inline MachineInstr *getTombstoneKey() {
+    return reinterpret_cast<MachineInstr*>(-1);
+  }
+
+  static unsigned getHashValue(const MachineInstr* const &MI);
+
+  static bool isEqual(const MachineInstr* const &LHS,
+                      const MachineInstr* const &RHS) {
+    if (RHS == getEmptyKey() || RHS == getTombstoneKey() ||
+        LHS == getEmptyKey() || LHS == getTombstoneKey())
+      return LHS == RHS;
+    return LHS->isIdenticalTo(RHS, MachineInstr::IgnoreVRegDefs);
+  }
+};
+
 //===----------------------------------------------------------------------===//
 // Debugging Support
 
diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h
index 01dc018..f2e5e10 100644
--- a/include/llvm/CodeGen/MachineRegisterInfo.h
+++ b/include/llvm/CodeGen/MachineRegisterInfo.h
@@ -115,6 +115,10 @@ public:
   /// register.
   bool use_empty(unsigned RegNo) const { return use_begin(RegNo) == use_end(); }
 
+  /// hasOneUse - Return true if there is exactly one instruction using the
+  /// specified register.
+  bool hasOneUse(unsigned RegNo) const;
+
   /// use_nodbg_iterator/use_nodbg_begin/use_nodbg_end - Walk all uses of the
   /// specified register, skipping those marked as Debug.
   typedef defusechain_iterator<true,false,true> use_nodbg_iterator;
@@ -129,6 +133,10 @@ public:
     return use_nodbg_begin(RegNo) == use_nodbg_end();
   }
 
+  /// hasOneNonDBGUse - Return true if there is exactly one non-Debug
+  /// instruction using the specified register.
+  bool hasOneNonDBGUse(unsigned RegNo) const;
+
   /// replaceRegWith - Replace all instances of FromReg with ToReg in the
   /// machine function.  This is like llvm-level X->replaceAllUsesWith(Y),
   /// except that it also changes any definitions of the register as well.
diff --git a/include/llvm/CodeGen/SelectionDAGISel.h b/include/llvm/CodeGen/SelectionDAGISel.h
index 23ff001..d9c1374 100644
--- a/include/llvm/CodeGen/SelectionDAGISel.h
+++ b/include/llvm/CodeGen/SelectionDAGISel.h
@@ -276,7 +276,6 @@ private:
   SDNode *Select_UNDEF(SDNode *N);
   SDNode *Select_EH_LABEL(SDNode *N);
   void CannotYetSelect(SDNode *N);
-  void CannotYetSelectIntrinsic(SDNode *N);
 
 private:
   void DoInstructionSelection();
diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index 950963e..21a0b98 100644
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -1027,11 +1027,15 @@ private:
   /// then they will be delete[]'d when the node is destroyed.
   uint16_t OperandsNeedDelete : 1;
 
+  /// HasDebugValue - This tracks whether this node has one or more dbg_value
+  /// nodes corresponding to it.
+  uint16_t HasDebugValue : 1;
+
 protected:
   /// SubclassData - This member is defined by this class, but is not used for
   /// anything.  Subclasses can use it to hold whatever state they find useful.
   /// This field is initialized to zero by the ctor.
-  uint16_t SubclassData : 15;
+  uint16_t SubclassData : 14;
 
 private:
   /// NodeId - Unique id per SDNode in the DAG.
@@ -1094,6 +1098,12 @@ public:
     return ~NodeType;
   }
 
+  /// getHasDebugValue - get this bit.
+  bool getHasDebugValue() const { return HasDebugValue; }
+
+  /// setHasDebugValue - set this bit.
+  void setHasDebugValue(bool b) { HasDebugValue = b; }
+
   /// use_empty - Return true if there are no uses of this node.
   ///
   bool use_empty() const { return UseList == NULL; }
@@ -1357,8 +1367,8 @@ protected:
 
   SDNode(unsigned Opc, const DebugLoc dl, SDVTList VTs, const SDValue *Ops,
          unsigned NumOps)
-    : NodeType(Opc), OperandsNeedDelete(true), SubclassData(0),
-      NodeId(-1),
+    : NodeType(Opc), OperandsNeedDelete(true), HasDebugValue(false),
+      SubclassData(0), NodeId(-1),
       OperandList(NumOps ? new SDUse[NumOps] : 0),
       ValueList(VTs.VTs), UseList(NULL),
       NumOperands(NumOps), NumValues(VTs.NumVTs),