Attempt to fix MSAN failures in benchmarks

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@369482 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/benchmarks/algorithms.bench.cpp b/benchmarks/algorithms.bench.cpp
index eee8a4d..f5f0a02 100644
--- a/benchmarks/algorithms.bench.cpp
+++ b/benchmarks/algorithms.bench.cpp
@@ -256,7 +256,13 @@
     return 1;
 
   const std::vector<size_t> Quantities = {1 << 0, 1 << 2,  1 << 4,  1 << 6,
-                                          1 << 8, 1 << 10, 1 << 14, 1 << 18};
+                                          1 << 8, 1 << 10, 1 << 14,
+    // Running each benchmark in parallel consumes too much memory with MSAN
+    // and can lead to the test process being killed.
+#if !TEST_HAS_FEATURE(memory_sanitizer)
+                                          1 << 18
+#endif
+  };
   makeCartesianProductBenchmark<Sort, AllValueTypes, AllOrders>(Quantities);
   makeCartesianProductBenchmark<StableSort, AllValueTypes, AllOrders>(
       Quantities);