Extend the IL for selecting TLS models (PR9788)

This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as

  @x = thread_local(initialexec) global i32 42

if it will not be used in a shared library that is dlopen'ed.

If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159077 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Utils/CloneModule.cpp

@@ -53,7 +53,7 @@ Module *llvm::CloneModule(const Module *M, ValueToValueMapTy &VMap) {
                                             I->isConstant(), I->getLinkage(),
                                             (Constant*) 0, I->getName(),
                                             (GlobalVariable*) 0,
-                                            I->isThreadLocal(),
+                                            I->getThreadLocalMode(),
                                             I->getType()->getAddressSpace());
     GV->copyAttributesFrom(I);
     VMap[I] = GV;