[IR] Use range-based for loops (NFC) (#97575)

Author: kazutakahirata

llvm/lib/IR/DIBuilder.cpp

@@ -79,9 +79,9 @@ void DIBuilder::finalize() {
   // list. Use a set to remove the duplicates while we transform the
   // TrackingVHs back into Values.
   SmallPtrSet<Metadata *, 16> RetainSet;
-  for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
-    if (RetainSet.insert(AllRetainTypes[I]).second)
-      RetainValues.push_back(AllRetainTypes[I]);
+  for (const TrackingMDNodeRef &N : AllRetainTypes)
+    if (RetainSet.insert(N).second)
+      RetainValues.push_back(N);
 
   if (!RetainValues.empty())
     CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));

llvm/lib/IR/LegacyPassManager.cpp

@@ -823,9 +823,8 @@ void PMTopLevelManager::dumpPasses() const {
     return;
 
   // Print out the immutable passes
-  for (unsigned i = 0, e = ImmutablePasses.size(); i != e; ++i) {
-    ImmutablePasses[i]->dumpPassStructure(0);
-  }
+  for (ImmutablePass *Pass : ImmutablePasses)
+    Pass->dumpPassStructure(0);
 
   // Every class that derives from PMDataManager also derives from Pass
   // (sometimes indirectly), but there's no inheritance relationship