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diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
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+//===---- LiveRangeEdit.h - Basic tools for split and spill -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// The LiveRangeEdit class represents changes done to a virtual register when it
+// is spilled or split.
+//
+// The parent register is never changed. Instead, a number of new virtual
+// registers are created and added to the newRegs vector.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_LIVERANGEEDIT_H
+#define LLVM_CODEGEN_LIVERANGEEDIT_H
+
+#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/ADT/SmallPtrSet.h"
+
+namespace llvm {
+
+class AliasAnalysis;
+class LiveIntervals;
+class MachineRegisterInfo;
+class VirtRegMap;
+
+class LiveRangeEdit {
+  LiveInterval &parent_;
+  SmallVectorImpl<LiveInterval*> &newRegs_;
+  const SmallVectorImpl<LiveInterval*> &uselessRegs_;
+
+  /// firstNew_ - Index of the first register added to newRegs_.
+  const unsigned firstNew_;
+
+  /// scannedRemattable_ - true when remattable values have been identified.
+  bool scannedRemattable_;
+
+  /// remattable_ - Values defined by remattable instructions as identified by
+  /// tii.isTriviallyReMaterializable().
+  SmallPtrSet<VNInfo*,4> remattable_;
+
+  /// rematted_ - Values that were actually rematted, and so need to have their
+  /// live range trimmed or entirely removed.
+  SmallPtrSet<VNInfo*,4> rematted_;
+
+  /// scanRemattable - Identify the parent_ values that may rematerialize.
+  void scanRemattable(LiveIntervals &lis,
+                      const TargetInstrInfo &tii,
+                      AliasAnalysis *aa);
+
+  /// allUsesAvailableAt - Return true if all registers used by OrigMI at
+  /// OrigIdx are also available with the same value at UseIdx.
+  bool allUsesAvailableAt(const MachineInstr *OrigMI, SlotIndex OrigIdx,
+                          SlotIndex UseIdx, LiveIntervals &lis);
+
+public:
+  /// Create a LiveRangeEdit for breaking down parent into smaller pieces.
+  /// @param parent The register being spilled or split.
+  /// @param newRegs List to receive any new registers created. This needn't be
+  ///                empty initially, any existing registers are ignored.
+  /// @param uselessRegs List of registers that can't be used when
+  ///        rematerializing values because they are about to be removed.
+  LiveRangeEdit(LiveInterval &parent,
+                SmallVectorImpl<LiveInterval*> &newRegs,
+                const SmallVectorImpl<LiveInterval*> &uselessRegs)
+    : parent_(parent), newRegs_(newRegs), uselessRegs_(uselessRegs),
+      firstNew_(newRegs.size()), scannedRemattable_(false) {}
+
+  LiveInterval &getParent() const { return parent_; }
+  unsigned getReg() const { return parent_.reg; }
+
+  /// Iterator for accessing the new registers added by this edit.
+  typedef SmallVectorImpl<LiveInterval*>::const_iterator iterator;
+  iterator begin() const { return newRegs_.begin()+firstNew_; }
+  iterator end() const { return newRegs_.end(); }
+  unsigned size() const { return newRegs_.size()-firstNew_; }
+  bool empty() const { return size() == 0; }
+  LiveInterval *get(unsigned idx) const { return newRegs_[idx+firstNew_]; }
+
+  /// create - Create a new register with the same class and stack slot as
+  /// parent.
+  LiveInterval &create(MachineRegisterInfo&, LiveIntervals&, VirtRegMap&);
+
+  /// anyRematerializable - Return true if any parent values may be
+  /// rematerializable.
+  /// This function must be called before ny rematerialization is attempted.
+  bool anyRematerializable(LiveIntervals&, const TargetInstrInfo&,
+                           AliasAnalysis*);
+
+  /// Remat - Information needed to rematerialize at a specific location.
+  struct Remat {
+    VNInfo *ParentVNI;      // parent_'s value at the remat location.
+    MachineInstr *OrigMI;   // Instruction defining ParentVNI.
+    explicit Remat(VNInfo *ParentVNI) : ParentVNI(ParentVNI), OrigMI(0) {}
+  };
+
+  /// canRematerializeAt - Determine if ParentVNI can be rematerialized at
+  /// UseIdx. It is assumed that parent_.getVNINfoAt(UseIdx) == ParentVNI.
+  /// When cheapAsAMove is set, only cheap remats are allowed.
+  bool canRematerializeAt(Remat &RM,
+                          SlotIndex UseIdx,
+                          bool cheapAsAMove,
+                          LiveIntervals &lis);
+
+  /// rematerializeAt - Rematerialize RM.ParentVNI into DestReg by inserting an
+  /// instruction into MBB before MI. The new instruction is mapped, but
+  /// liveness is not updated.
+  /// Return the SlotIndex of the new instruction.
+  SlotIndex rematerializeAt(MachineBasicBlock &MBB,
+                            MachineBasicBlock::iterator MI,
+                            unsigned DestReg,
+                            const Remat &RM,
+                            LiveIntervals&,
+                            const TargetInstrInfo&,
+                            const TargetRegisterInfo&);
+
+  /// markRematerialized - explicitly mark a value as rematerialized after doing
+  /// it manually.
+  void markRematerialized(VNInfo *ParentVNI) {
+    rematted_.insert(ParentVNI);
+  }
+
+  /// didRematerialize - Return true if ParentVNI was rematerialized anywhere.
+  bool didRematerialize(VNInfo *ParentVNI) const {
+    return rematted_.count(ParentVNI);
+  }
+};
+
+}
+
+#endif