[mlir] [llvm] [mlir] Add config for PDL (PR #69927)

[Mehdi Amini via llvm-commits]

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@@ -3312,6 +3312,7 @@ auto ConversionTarget::getOpInfo(OperationName op) const
   return std::nullopt;
 }
 
+#if MLIR_ENABLE_PDL
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joker-eph wrote:

Can we extract all of this in a separate .cpp and handle this with separate CMakeLibraries?

https://github.com/llvm/llvm-project/pull/69927