diff --git a/src/configuration/ArcanistSettings.php b/src/configuration/ArcanistSettings.php
--- a/src/configuration/ArcanistSettings.php
+++ b/src/configuration/ArcanistSettings.php
@@ -21,6 +21,14 @@
           'details.'),
         'example' => '"arc:amended, arc:prompt"',
       ),
+      'generated-paths' => array(
+        'type' => 'list<regex>',
+        'help' => pht(
+          'Paths that are generated. These paths are not normally useful for '.
+          'code review and will be shown as collapsed in the Differential UI.'),
+        'default' => array(),
+        'example' => '["(^src/__phutil_library_map__\\.php$)"]',
+      ),
       'load' => array(
         'type' => 'list',
         'legacy' => 'phutil_libraries',
diff --git a/src/workflow/ArcanistDiffWorkflow.php b/src/workflow/ArcanistDiffWorkflow.php
--- a/src/workflow/ArcanistDiffWorkflow.php
+++ b/src/workflow/ArcanistDiffWorkflow.php
@@ -525,6 +525,7 @@
     $this->updateLintDiffProperty();
     $this->updateUnitDiffProperty();
     $this->updateLocalDiffProperty();
+    $this->updateGeneratedDiffProperty();
     $this->resolveDiffPropertyUpdates();
 
     $output_json = $this->getArgument('json');
@@ -2411,6 +2412,18 @@
     $this->updateDiffProperty('local:commits', json_encode($local_info));
   }
 
+  /**
+   * Update generated paths for the diff.
+   *
+   * @task diffprop
+   */
+  private function updateGeneratedDiffProperty() {
+    $paths = $this->getWorkingCopy()->getProjectConfig('generated-paths');
+
+    if ($paths) {
+      $this->updateDiffProperty('arc:generated', json_encode($paths));
+    }
+  }
 
   /**
    * Update an arbitrary diff property.