1 files changed, 6 insertions, 7 deletions
diff --git a/include/llvm/IR/ValueMap.h b/include/llvm/IR/ValueMap.h
index 43a79c7..aa8a29d 100644
--- a/include/llvm/IR/ValueMap.h
+++ b/include/llvm/IR/ValueMap.h
@@ -29,6 +29,7 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/IR/ValueHandle.h"
 #include "llvm/Support/Mutex.h"
+#include "llvm/Support/UniqueLock.h"
 #include "llvm/Support/type_traits.h"
 #include <iterator>
 
@@ -111,7 +112,7 @@ public:
 
   void clear() { Map.clear(); }
 
-  /// Return 1 if the specified key is in the map, 0 otherwise.
+  /// Return 1 if the specified key is in the map, 0 otherwise.
   size_type count(const KeyT &Val) const {
     return Map.find_as(Val) == Map.end() ? 0 : 1;
   }
@@ -216,12 +217,11 @@ public:
     // Make a copy that won't get changed even when *this is destroyed.
     ValueMapCallbackVH Copy(*this);
     typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
+    unique_lock<typename Config::mutex_type> Guard;
     if (M)
-      M->acquire();
+      Guard = unique_lock<typename Config::mutex_type>(*M);
     Config::onDelete(Copy.Map->Data, Copy.Unwrap());  // May destroy *this.
     Copy.Map->Map.erase(Copy);  // Definitely destroys *this.
-    if (M)
-      M->release();
   }
   void allUsesReplacedWith(Value *new_key) override {
     assert(isa<KeySansPointerT>(new_key) &&
@@ -229,8 +229,9 @@ public:
     // Make a copy that won't get changed even when *this is destroyed.
     ValueMapCallbackVH Copy(*this);
     typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
+    unique_lock<typename Config::mutex_type> Guard;
     if (M)
-      M->acquire();
+      Guard = unique_lock<typename Config::mutex_type>(*M);
 
     KeyT typed_new_key = cast<KeySansPointerT>(new_key);
     // Can destroy *this:
@@ -245,8 +246,6 @@ public:
         Copy.Map->insert(std::make_pair(typed_new_key, Target));
       }
     }
-    if (M)
-      M->release();
   }
 };