Subzero: Refactor x86 register definitions to use the alias mechanism.

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 364 matching lines @@
   InstCall() = delete;
   InstCall(const InstCall &) = delete;
   InstCall &operator=(const InstCall &) = delete;
 
 public:
   static InstCall *create(Cfg *Func, SizeT NumArgs, Variable *Dest,
                           Operand *CallTarget, bool HasTailCall) {
     /// Set HasSideEffects to true so that the call instruction can't be
     /// dead-code eliminated. IntrinsicCalls can override this if the particular
     /// intrinsic is deletable and has no side-effects.
-    const bool HasSideEffects = true;
-    const InstKind Kind = Inst::Call;
+    constexpr bool HasSideEffects = true;
+    constexpr InstKind Kind = Inst::Call;
     return new (Func->allocate<InstCall>()) InstCall(
         Func, NumArgs, Dest, CallTarget, HasTailCall, HasSideEffects, Kind);
   }
   void addArg(Operand *Arg) { addSource(Arg); }
   Operand *getCallTarget() const { return getSrc(0); }
   Operand *getArg(SizeT I) const { return getSrc(I + 1); }
   SizeT getNumArgs() const { return getSrcSize() - 1; }
   bool isTailcall() const { return HasTailCall; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Call; }
@@ skipping 582 matching lines @@
   static void noteHead(Ice::Inst *, Ice::Inst *) {}
   void deleteNode(Ice::Inst *) {}
 
 private:
   mutable ilist_half_node<Ice::Inst> Sentinel;
 };
 
 } // end of namespace llvm
 
 #endif // SUBZERO_SRC_ICEINST_H