Index: lldb/include/lldb/Core/DataFileCache.h
===================================================================
--- lldb/include/lldb/Core/DataFileCache.h
+++ lldb/include/lldb/Core/DataFileCache.h
@@ -15,6 +15,7 @@
 #include "lldb/lldb-forward.h"
 #include "llvm/Support/Caching.h"
 #include <mutex>
+#include <unordered_map>
 
 namespace lldb_private {
 
@@ -190,7 +191,7 @@
 
 private:
   std::vector<ConstString> m_strings;
-  std::map<ConstString, uint32_t> m_string_to_offset;
+  std::unordered_map<ConstString, uint32_t> m_string_to_offset;
   /// Skip one byte to start the string table off with an empty string.
   uint32_t m_next_offset = 1;
 };
Index: lldb/include/lldb/Utility/ConstString.h
===================================================================
--- lldb/include/lldb/Utility/ConstString.h
+++ lldb/include/lldb/Utility/ConstString.h
@@ -464,6 +464,16 @@
 }
 } // namespace llvm
 
+namespace std {
+
+template <> struct hash<lldb_private::ConstString> {
+  std::size_t operator()(const lldb_private::ConstString &str) const {
+    return reinterpret_cast<std::size_t>(str.GetCString());
+  }
+};
+
+} // namespace std
+
 LLVM_YAML_IS_SEQUENCE_VECTOR(lldb_private::ConstString)
 
 #endif // LLDB_UTILITY_CONSTSTRING_H