Improve use of CfgLocalAllocator and introduce containers that use it.

src/IceGlobalContext.cpp

 //===- subzero/src/IceGlobalContext.cpp - Global context defs -------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 704 matching lines @@
 
   // Transform bar ==> Prefixbar
   //                   ^^^^^^
   return TestPrefix + Name;
 }
 
 GlobalContext::~GlobalContext() {
   llvm::DeleteContainerPointers(AllThreadContexts);
   LockedPtr<DestructorArray> Dtors = getDestructors();
   // Destructors are invoked in the opposite object construction order.
-  for (auto DtorIter = Dtors->crbegin(); DtorIter != Dtors->crend();
-       ++DtorIter) {
-    (*DtorIter)();
-  }
+  for (const auto &Dtor : reverse_range(*Dtors))
+    Dtor();
 }
 
 // TODO(stichnot): Consider adding thread-local caches of constant pool entries
 // to reduce contention.
 
 // All locking is done by the getConstantInt[0-9]+() target function.
 Constant *GlobalContext::getConstantInt(Type Ty, int64_t Value) {
   switch (Ty) {
   case IceType_i1:
     return getConstantInt1(Value);
@@ skipping 270 matching lines @@
   Ctx = Func->getContext();
   Active =
       Func->getFocusedTiming() || Ctx->getFlags().getSubzeroTimingEnabled();
   if (Active)
     Ctx->pushTimer(ID, StackID);
 }
 
 ICE_TLS_DEFINE_FIELD(GlobalContext::ThreadContext *, GlobalContext, TLS);
 
 } // end of namespace Ice