[llvm] [mlir][Transform] Create a transform interpreter and a preloader pass (PR #68661)

[Nicolas Vasilache via llvm-commits]

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@@ -42,4 +42,35 @@ def InferEffectsPass : Pass<"transform-infer-effects"> {
   }];
 }
 
+def PreloadLibraryPass : Pass<"transform-preload-library"> {
+  let summary = "preload transform dialect library";
+  let description = [{
+    This pass preloads a transform library and makes it available to a subsequent
+    transform interpreter passes. The preloading occurs into the Transform
+    dialect and thus provides very limited functionality that does not scale.
+
+    Warning: Only a single such pass should exist for a given MLIR context.
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nicolasvasilache wrote:

good point, I'll investigate and see if we can relax that once I plug into a more complex use case like IREE.
For now let's just say I feel safer with a conservative disclaimer.

https://github.com/llvm/llvm-project/pull/68661