[Mem2Reg] Delete unused PointerAllocaValues

It is unused after AliasSetTracker support was removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358352 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index 4cdef6d..d58e1ea 100644
--- a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -249,11 +249,6 @@
   /// to.
   DenseMap<PHINode *, unsigned> PhiToAllocaMap;
 
-  /// If we are updating an AliasSetTracker, then for each alloca that is of
-  /// pointer type, we keep track of what to copyValue to the inserted PHI
-  /// nodes here.
-  std::vector<Value *> PointerAllocaValues;
-
   /// For each alloca, we keep track of the dbg.declare intrinsic that
   /// describes it, if any, so that we can convert it to a dbg.value
   /// intrinsic if the alloca gets promoted.