If you include bitcode when you upload your app to iTunes Connect, the App Store compiles the bitcode and generates the dSYM files. In Xcode, you can download the dSYM files from iTunes Connect before you view crash logs in the Devices and Simulators window.
In the Archives organizer, select the archive.
Click the Download dSYMs button.
Xcode inserts the .dSYM files in the selected archive.
Important: Xcode uses the version number and build string in the archive to request the .dSYM files. Therefore, set the version number and build string before distributing your app.
When the dSYM files are indexed by Spotlight they will be used to automatically symbolicate crash logs in the Crashes organizer. In addition, the dSYM files will be used to symbolicate crash logs that are found on devices that appear in the Devices and Simulators window.