Iasm and obj lowering for advanced switch lowering.

src/IceInst.h

Index: src/IceInst.h
diff --git a/src/IceInst.h b/src/IceInst.h
index 48b18f4415b88db94c09a3cd9c8a091663e262e3..6bfd7af171f140db67b2b8390855b59f0be58ebf 100644
--- a/src/IceInst.h
+++ b/src/IceInst.h
@@ -914,17 +914,24 @@ public:
     return new (Func->allocate<InstJumpTable>())
         InstJumpTable(Func, NumTargets, Default);
   }
-  void emit(const Cfg *Func) const override;
-  void emitIAS(const Cfg *Func) const override;
   void addTarget(SizeT TargetIndex, CfgNode *Target) {
     assert(TargetIndex < NumTargets);
     Targets[TargetIndex] = Target;
   }
   bool repointEdges(CfgNode *OldNode, CfgNode *NewNode) override;
-  IceString getName(const Cfg *Func) const;
+  SizeT getId() const { return Id; }
+  SizeT getNumTargets() const { return NumTargets; }
+  CfgNode *getTarget(SizeT I) const {
+    assert(I < NumTargets);
+    return Targets[I];
+  }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == JumpTable; }
 
+  static IceString makeName(const IceString &FuncName, SizeT Id) {
+    return ".L" + FuncName + "$jumptable$__" + std::to_string(Id);
+  }
+
 private:
   InstJumpTable(Cfg *Func, SizeT NumTargets, CfgNode *Default);
   void destroy(Cfg *Func) override {
@@ -932,7 +939,7 @@ private:
     Inst::destroy(Func);
   }
 
-  const SizeT LabelNumber;
+  const SizeT Id;
   const SizeT NumTargets;
   CfgNode **Targets;
 };