Index: lib/Transforms/Scalar/ADCE.cpp
===================================================================
--- lib/Transforms/Scalar/ADCE.cpp
+++ lib/Transforms/Scalar/ADCE.cpp
@@ -18,6 +18,7 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/GraphTraits.h"
+#include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/PostOrderIterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
@@ -118,7 +119,8 @@
   PostDominatorTree &PDT;
 
   /// Mapping of blocks to associated information, an element in BlockInfoVec.
-  DenseMap<BasicBlock *, BlockInfoType> BlockInfo;
+  /// Use MapVector to get deterministic iteration order.
+  MapVector<BasicBlock *, BlockInfoType> BlockInfo;
   bool isLive(BasicBlock *BB) { return BlockInfo[BB].Live; }
 
   /// Mapping of instructions to associated information.
@@ -209,11 +211,6 @@
 }
 
 void AggressiveDeadCodeElimination::initialize() {
-  auto NumBlocks = F.size();
-
-  // We will have an entry in the map for each block so we grow the
-  // structure to twice that size to keep the load factor low in the hash table.
-  BlockInfo.reserve(NumBlocks);
   size_t NumInsts = 0;
 
   // Iterate over blocks and initialize BlockInfoVec entries, count