[lldb] Add extra debugging info to TSan Swift access race test

This test has failed once, and this commit adds more detail to the assertion so that any future failures can be more easily diagnosed.

Author: DanBlackwell

lldb/test/API/functionalities/tsan/swift-access-race/TestTsanSwiftAccessRace.py

@@ -53,20 +53,27 @@ def do_test(self):
                 runtimes.append(os.path.join(libspec.GetDirectory(), libspec.GetFilename()))
         self.registerSharedLibrariesWithTarget(target, runtimes)
 
-        # Unfortunatley the runtime itself isn't 100% reliable in reporting TSAN errors.
-        process = None
-        stop_reason = lldb.eStopReasonInvalid
+        # Unfortunately the runtime itself isn't 100% reliable in reporting TSAN errors.
+        failure_reasons = []
+        stop_reason = None
         for retry in range(5):
-            process = target.LaunchSimple(None, None, self.get_process_working_directory())
-            if not process:
+            error = lldb.SBError()
+            info = lldb.SBLaunchInfo([exe_name])
+            info.SetWorkingDirectory(self.get_process_working_directory())
+            process = target.Launch(info, error)
+            if not error.success:
+                failure_reasons.append(f"Failed to bring up process, error: {error.value}")
                 continue
+
             stop_reason = process.GetSelectedThread().GetStopReason()
             if stop_reason == lldb.eStopReasonInstrumentation:
                 break
+            failure_reasons.append(f"Invalid stop_reason: {stop_reason}")
 
         self.assertEqual(
-            process.GetSelectedThread().GetStopReason(),
-            lldb.eStopReasonInstrumentation)
+            stop_reason, 
+            lldb.eStopReasonInstrumentation,
+            f"Failed with {len(failure_reasons)} attempts with reasons: {failure_reasons}")
 
         # the stop reason of the thread should be a TSan report.
         self.expect("thread list", "A Swift access race should be detected",