Subzero: Refactor some common TargetLowering initializations.

src/IceTargetLoweringX86BaseImpl.h

 //===- subzero/src/IceTargetLoweringX86BaseImpl.h - x86 lowering -*- C++ -*-==//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 263 matching lines @@
           (TargetInstructionSet::X86InstructionSet_End -
            TargetInstructionSet::X86InstructionSet_Begin),
       "Traits::InstructionSet range different from TargetInstructionSet");
   if (Func->getContext()->getFlags().getTargetInstructionSet() !=
       TargetInstructionSet::BaseInstructionSet) {
     InstructionSet = static_cast<typename Traits::InstructionSet>(
         (Func->getContext()->getFlags().getTargetInstructionSet() -
          TargetInstructionSet::X86InstructionSet_Begin) +
         Traits::InstructionSet::Begin);
   }
-  // TODO: Don't initialize IntegerRegisters and friends every time. Instead,
-  // initialize in some sort of static initializer for the class.
+}
+
+template <class Machine> void TargetX86Base<Machine>::staticInit() {
   Traits::initRegisterSet(&TypeToRegisterSet, &RegisterAliases, &ScratchRegs);
 }
 
 template <class Machine> void TargetX86Base<Machine>::translateO2() {
   TimerMarker T(TimerStack::TT_O2, Func);
 
   if (!Ctx->getFlags().getPhiEdgeSplit()) {
     // Lower Phi instructions.
     Func->placePhiLoads();
     if (Func->hasError())
@@ skipping 5562 matching lines @@
   }
   // the offset is not eligible for blinding or pooling, return the original
   // mem operand
   return MemOperand;
 }
 
 } // end of namespace X86Internal
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERINGX86BASEIMPL_H