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diff --git a/contrib/llvm/lib/CodeGen/SpillPlacement.h b/contrib/llvm/lib/CodeGen/SpillPlacement.h
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+//===-- SpillPlacement.h - Optimal Spill Code Placement --------*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This analysis computes the optimal spill code placement between basic blocks.
+//
+// The runOnMachineFunction() method only precomputes some profiling information
+// about the CFG. The real work is done by placeSpills() which is called by the
+// register allocator.
+//
+// Given a variable that is live across multiple basic blocks, and given
+// constraints on the basic blocks where the variable is live, determine which
+// edge bundles should have the variable in a register and which edge bundles
+// should have the variable in a stack slot.
+//
+// The returned bit vector can be used to place optimal spill code at basic
+// block entries and exits. Spill code placement inside a basic block is not
+// considered.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_SPILLPLACEMENT_H
+#define LLVM_CODEGEN_SPILLPLACEMENT_H
+
+#include "llvm/CodeGen/MachineFunctionPass.h"
+
+namespace llvm {
+
+class BitVector;
+class EdgeBundles;
+class MachineBasicBlock;
+class MachineLoopInfo;
+template <typename> class SmallVectorImpl;
+
+class SpillPlacement  : public MachineFunctionPass {
+  struct Node;
+  const MachineFunction *MF;
+  const EdgeBundles *bundles;
+  const MachineLoopInfo *loops;
+  Node *nodes;
+
+  // Nodes that are active in the current computation. Owned by the placeSpills
+  // caller.
+  BitVector *ActiveNodes;
+
+public:
+  static char ID; // Pass identification, replacement for typeid.
+
+  SpillPlacement() : MachineFunctionPass(ID), nodes(0) {}
+  ~SpillPlacement() { releaseMemory(); }
+
+  /// BorderConstraint - A basic block has separate constraints for entry and
+  /// exit.
+  enum BorderConstraint {
+    DontCare,  ///< Block doesn't care / variable not live.
+    PrefReg,   ///< Block entry/exit prefers a register.
+    PrefSpill, ///< Block entry/exit prefers a stack slot.
+    MustSpill  ///< A register is impossible, variable must be spilled.
+  };
+
+  /// BlockConstraint - Entry and exit constraints for a basic block.
+  struct BlockConstraint {
+    unsigned Number;            ///< Basic block number (from MBB::getNumber()).
+    BorderConstraint Entry : 8; ///< Constraint on block entry.
+    BorderConstraint Exit : 8;  ///< Constraint on block exit.
+  };
+
+  /// placeSpills - Compute the optimal spill code placement given the
+  /// constraints. No MustSpill constraints will be violated, and the smallest
+  /// possible number of PrefX constraints will be violated, weighted by
+  /// expected execution frequencies.
+  /// @param LiveBlocks Constraints for blocks that have the variable live in or
+  ///                   live out. DontCare/DontCare means the variable is live
+  ///                   through the block. DontCare/X means the variable is live
+  ///                   out, but not live in.
+  /// @param RegBundles Bit vector to receive the edge bundles where the
+  ///                   variable should be kept in a register. Each bit
+  ///                   corresponds to an edge bundle, a set bit means the
+  ///                   variable should be kept in a register through the
+  ///                   bundle. A clear bit means the variable should be
+  ///                   spilled.
+  /// @return True if a perfect solution was found, allowing the variable to be
+  ///         in a register through all relevant bundles.
+  bool placeSpills(const SmallVectorImpl<BlockConstraint> &LiveBlocks,
+                   BitVector &RegBundles);
+
+  /// getBlockFrequency - Return the estimated block execution frequency per
+  /// function invocation.
+  float getBlockFrequency(const MachineBasicBlock*);
+
+private:
+  virtual bool runOnMachineFunction(MachineFunction&);
+  virtual void getAnalysisUsage(AnalysisUsage&) const;
+  virtual void releaseMemory();
+
+  void activate(unsigned);
+  void prepareNodes(const SmallVectorImpl<BlockConstraint>&);
+  void iterate(const SmallVectorImpl<unsigned>&);
+};
+
+} // end namespace llvm
+
+#endif