[llvm] [mlir] Default DEBUG_TYPE to the current filename for logging (PR #158494)

[Jacques Pienaar via llvm-commits]

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@@ -1180,7 +1181,7 @@ The debug output can be enabled by passing the ``-debug`` command line argument.
   $ opt < a.bc > /dev/null -mypass
   <no output>
   $ opt < a.bc > /dev/null -mypass -debug
-  [my-pass:2] MyPass.cpp:123 I am here!
+  [2 my-pass MyPass.cpp:123 I am here!
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jpienaar wrote:

I think the examples maybe out of date.

https://github.com/llvm/llvm-project/pull/158494