[CFG/BasicBlock] Rename pred_const to const_pred. [NFC]

[asbirlea]

Summary

Rename pred_const_range to const_pred_range to make it consistent with
the other pred/succ iterator definitions: for successors this file defines const_succ_range; the predecessors constant iterators also use const as the first token: const_pred_iterator; there is also a definition in clang for const_pred_range.

[dblaikie]

I don't mind too strongly either way - but if you want to commit this, could you mention in the commit message which other types this is consistent with?

llvm/include/llvm/IR/CFG.h

Use &getUse() const {
     return It.getUse();
   }
 };
 
 using pred_iterator = PredIterator<BasicBlock, Value::user_iterator>;
 using const_pred_iterator =
     PredIterator<const BasicBlock, Value::const_user_iterator>;
 using pred_range = iterator_range<pred_iterator>;
-using pred_const_range = iterator_range<const_pred_iterator>;
+using const_pred_range = iterator_range<const_pred_iterator>;
 
 inline pred_iterator pred_begin(BasicBlock *BB) { return pred_iterator(BB); }
 inline const_pred_iterator pred_begin(const BasicBlock *BB) {
   return const_pred_iterator(BB);
 }
 inline pred_iterator pred_end(BasicBlock *BB) { return pred_iterator(BB, true);}
 inline const_pred_iterator pred_end(const BasicBlock *BB) {
   return const_pred_iterator(BB, true);
 }
 inline bool pred_empty(const BasicBlock *BB) {
   return pred_begin(BB) == pred_end(BB);
 }
 /// Get the number of predecessors of \p BB. This is a linear time operation.
 /// Use \ref BasicBlock::hasNPredecessors() or hasNPredecessorsOrMore if able.
 inline unsigned pred_size(const BasicBlock *BB) {
   return std::distance(pred_begin(BB), pred_end(BB));
 }
 inline pred_range predecessors(BasicBlock *BB) {
   return pred_range(pred_begin(BB), pred_end(BB));
 }
-inline pred_const_range predecessors(const BasicBlock *BB) {
-  return pred_const_range(pred_begin(BB), pred_end(BB));
+inline const_pred_range predecessors(const BasicBlock *BB) {
+  return const_pred_range(pred_begin(BB), pred_end(BB));
 }
 
 //===----------------------------------------------------------------------===//
 // Instruction and BasicBlock succ_iterator helpers
 //===----------------------------------------------------------------------===//
 
 template <class InstructionT, class BlockT>
 class SuccIterator