Subzero : Live Range Splitting after initial Register Allocation

src/IceInst.h

 //===- subzero/src/IceInst.h - High-level instructions ----------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 93 matching lines @@
   Variable *getDest() const { return Dest; }
 
   SizeT getSrcSize() const { return Srcs.size(); }
   Operand *getSrc(SizeT I) const {
     assert(I < getSrcSize());
     return Srcs[I];
   }
   void replaceSource(SizeT Index, Operand *Replacement) {
     assert(Index < getSrcSize());
     assert(!isDeleted());
-    assert(LiveRangesEnded == 0);
+    //     assert(LiveRangesEnded == 0);
     // Invalidates liveness info because the use Srcs[Index] is removed.
     Srcs[Index] = Replacement;
   }
 
   bool isLastUse(const Operand *Src) const;
   void spliceLivenessInfo(Inst *OrigInst, Inst *SpliceAssn);
 
   /// Returns a list of out-edges corresponding to a terminator instruction,
   /// which is the last instruction of the block. The list must not contain
   /// duplicates.
@@ skipping 52 matching lines @@
   virtual void emitIAS(const Cfg *Func) const { emit(Func); }
   virtual void dump(const Cfg *Func) const;
   virtual void dumpExtras(const Cfg *Func) const;
   void dumpDecorated(const Cfg *Func) const;
   void emitSources(const Cfg *Func) const;
   void dumpSources(const Cfg *Func) const;
   void dumpDest(const Cfg *Func) const;
   virtual bool isRedundantAssign() const { return false; }
 
   virtual ~Inst() = default;
+  void replaceDest(Variable *Var) { Dest = Var; }
 
 protected:
   Inst(Cfg *Func, InstKind Kind, SizeT MaxSrcs, Variable *Dest);
   void addSource(Operand *Src) {
     assert(Src);
     Srcs.push_back(Src);
   }
   void setLastUse(SizeT VarIndex) {
     if (VarIndex < CHAR_BIT * sizeof(LiveRangesEnded))
       LiveRangesEnded |= (((LREndedBits)1u) << VarIndex);
@@ skipping 950 matching lines @@
 
 inline Inst *iteratorToInst(InstList::iterator Iter) { return &*Iter; }
 
 inline const Inst *iteratorToInst(InstList::const_iterator Iter) {
   return &*Iter;
 }
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEINST_H