[llvm] [llvm][llvm-lit] Add option to create unique result file names if results already exist (PR #112729)

[James Henderson via llvm-commits]

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@@ -0,0 +1,28 @@
+# Check that lit will not overwrite existing result files when given
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jh7370 wrote:

Something I've been encouraging people to do with tests I've reviewed is use `##` (or equivalent) for "true" comments, to help distinguish them from `RUN` and `CHECK` style lines. I feel it makes the test file easier to read.

https://github.com/llvm/llvm-project/pull/112729