[llvm] [lit] Add --per-test-output-subdir to isolate test_exec_root across concurrent runs (PR #206826)

[David Young via llvm-commits]

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@@ -363,6 +363,22 @@ def parse_args():
         action="store_true",
         help="Enable individual test case coverage",
     )
+    execution_group.add_argument(
+        "--test-output-root",
+        dest="test_output_root",
+        metavar="DIR",
+        default=None,
+        help="Write all test output under DIR instead of each test suite's "
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youngd007 wrote:

updated

https://github.com/llvm/llvm-project/pull/206826