Add range adapters predecessors() and successors() for BBs

Use them in two isolated transforms so we know they work and aren't dead
code.

llvm-svn: 228173
diff --git a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
index 3282022..7e48ce3 100644
--- a/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/llvm/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -561,8 +561,7 @@
     // Now check every path from the entry block to the load for transparency.
     // To do this, we perform a depth first search on the inverse CFG from the
     // loading block.
-    for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
-      BasicBlock *P = *PI;
+    for (BasicBlock *P : predecessors(BB)) {
       for (BasicBlock *TranspBB : inverse_depth_first_ext(P, TranspBlocks))
         if (AA.canBasicBlockModify(*TranspBB, Loc))
           return false;
diff --git a/llvm/lib/Transforms/IPO/PartialInlining.cpp b/llvm/lib/Transforms/IPO/PartialInlining.cpp
index 76d6dfa..4a7cb7b 100644
--- a/llvm/lib/Transforms/IPO/PartialInlining.cpp
+++ b/llvm/lib/Transforms/IPO/PartialInlining.cpp
@@ -58,13 +58,13 @@
   BasicBlock* returnBlock = nullptr;
   BasicBlock* nonReturnBlock = nullptr;
   unsigned returnCount = 0;
-  for (succ_iterator SI = succ_begin(entryBlock), SE = succ_end(entryBlock);
-       SI != SE; ++SI)
-    if (isa<ReturnInst>((*SI)->getTerminator())) {
-      returnBlock = *SI;
+  for (BasicBlock *BB : successors(entryBlock)) {
+    if (isa<ReturnInst>(BB->getTerminator())) {
+      returnBlock = BB;
       returnCount++;
     } else
-      nonReturnBlock = *SI;
+      nonReturnBlock = BB;
+  }
   
   if (returnCount != 1)
     return nullptr;