Start adding an integrated assembler.

src/IceInst.h

Index: src/IceInst.h
diff --git a/src/IceInst.h b/src/IceInst.h
index fd01e92eaeaca25d077fee7893f7c61ef07e44f3..41895d90cc69ae506f25398f2c0aadd579f653e0 100644
--- a/src/IceInst.h
+++ b/src/IceInst.h
@@ -102,6 +102,7 @@ public:
   void liveness(InstNumberT InstNumber, llvm::BitVector &Live,
                 Liveness *Liveness, const CfgNode *Node);
   virtual void emit(const Cfg *Func) const;
+  virtual void emitIAS(const Cfg *Func) const;
   virtual void dump(const Cfg *Func) const;
   virtual void dumpExtras(const Cfg *Func) const;
   void dumpDecorated(const Cfg *Func) const;
@@ -739,6 +740,7 @@ private:
 class InstTarget : public Inst {
 public:
   virtual void emit(const Cfg *Func) const = 0;
+  virtual void emitIAS(const Cfg *Func) const = 0;
   virtual void dump(const Cfg *Func) const;
   virtual void dumpExtras(const Cfg *Func) const;
   static bool classof(const Inst *Inst) { return Inst->getKind() >= Target; }