[LowerTypeTests] Don't rely on doInitialization()

[davide]

Summary

In preparation for porting this pass to the new PM. Similar to what I did for CrossDSOCFI in http://reviews.llvm.org/D21357

[pcc]

lgtm

lib/Transforms/IPO/LowerTypeTests.cpp

struct LowerTypeTests : public ModulePass {
   Constant *createJumpTableEntry(GlobalObject *Src, Function *Dest,
                                  unsigned Distance);
   void verifyTypeMDNode(GlobalObject *GO, MDNode *Type);
   void buildBitSetsFromFunctions(ArrayRef<Metadata *> TypeIds,
                                  ArrayRef<Function *> Functions);
   void buildBitSetsFromDisjointSet(ArrayRef<Metadata *> TypeIds,
                                    ArrayRef<GlobalObject *> Globals);
   bool lower();
-
-  bool doInitialization(Module &M) override;
   bool runOnModule(Module &M) override;
 };
 
 } // anonymous namespace
 
 INITIALIZE_PASS(LowerTypeTests, "lowertypetests", "Lower type metadata", false,
                 false)
 char LowerTypeTests::ID = 0;
 
 ModulePass *llvm::createLowerTypeTestsPass() { return new LowerTypeTests; }
 
-bool LowerTypeTests::doInitialization(Module &Mod) {
-  M = &Mod;
-  const DataLayout &DL = Mod.getDataLayout();
-
-  Triple TargetTriple(M->getTargetTriple());
-  LinkerSubsectionsViaSymbols = TargetTriple.isMacOSX();
-  Arch = TargetTriple.getArch();
-  ObjectFormat = TargetTriple.getObjectFormat();
-
-  Int1Ty = Type::getInt1Ty(M->getContext());
-  Int8Ty = Type::getInt8Ty(M->getContext());
-  Int32Ty = Type::getInt32Ty(M->getContext());
-  Int32PtrTy = PointerType::getUnqual(Int32Ty);
-  Int64Ty = Type::getInt64Ty(M->getContext());
-  IntPtrTy = DL.getIntPtrType(M->getContext(), 0);
-
-  TypeTestCallSites.clear();
-
-  return false;
-}
-
 /// Build a bit set for TypeId using the object layouts in
 /// GlobalLayout.
 BitSetInfo LowerTypeTests::buildBitSet(
     Metadata *TypeId,
     const DenseMap<GlobalObject *, uint64_t> &GlobalLayout) {
   BitSetBuilder BSB;
 
   // Compute the byte offset of each address associated with this type
bool LowerTypeTests::lower() {
 
   return true;
 }
 
 bool LowerTypeTests::runOnModule(Module &M) {
   if (skipModule(M))
     return false;
 
+  this->M = &M;
+  const DataLayout &DL = M.getDataLayout();
+
+  Triple TargetTriple(M.getTargetTriple());
+  LinkerSubsectionsViaSymbols = TargetTriple.isMacOSX();
+  Arch = TargetTriple.getArch();
+  ObjectFormat = TargetTriple.getObjectFormat();
+
+  Int1Ty = Type::getInt1Ty(M.getContext());
+  Int8Ty = Type::getInt8Ty(M.getContext());
+  Int32Ty = Type::getInt32Ty(M.getContext());
+  Int32PtrTy = PointerType::getUnqual(Int32Ty);
+  Int64Ty = Type::getInt64Ty(M.getContext());
+  IntPtrTy = DL.getIntPtrType(M.getContext(), 0);
+
+  TypeTestCallSites.clear();
   return lower();
 }