[mlir][AsmPrinter] WIP - Attempt to fix roundtripping issue on op names containing multiple '.' characters.

[nicolasvasilache]

Summary

Operations such as transform.structured.tile currently do not properly roundtrip.
I am looking for guidance on how to fix and what generic test to add.
This current change solves the problem on my end but may not be desirable.

Please advise.

[rriddle]

We should have some test dialect operations that use default dialect, should be easy to use a test dialect operation with multiple dots within the regions of one of those operations.

mlir/lib/IR/AsmPrinter.cpp

2713

We'll likely want to shift checks like this to OpState::printOpName(in Operation.cpp). I agree with the direction of the patch though, if there are multiple . I think we should always print the full name. We only need to check for that if we would have stripped the dialect prefix, though. It should be easy to work that check into the function mentioned above.

mlir/lib/IR/AsmPrinter.cpp

private:
   unsigned nextConflictID = 0;
 
   /// These are the printing flags.  They control, eg., whether to print in
   /// generic form.
   OpPrintingFlags printerFlags;
 };
 } // namespace
 
-SSANameState::SSANameState(
-    Operation *op, const OpPrintingFlags &printerFlags)
+SSANameState::SSANameState(Operation *op, const OpPrintingFlags &printerFlags)
     : printerFlags(printerFlags) {
   llvm::SaveAndRestore<unsigned> valueIDSaver(nextValueID);
   llvm::SaveAndRestore<unsigned> argumentIDSaver(nextArgumentID);
   llvm::SaveAndRestore<unsigned> conflictIDSaver(nextConflictID);
 
   // The naming context includes `nextValueID`, `nextArgumentID`,
   // `nextConflictID` and `usedNames` scoped HashTable. This information is
   // carried from the parent region.
if (size_t numResults = op->getNumResults()) {
     os << " = ";
   }
 
   // If requested, always print the generic form.
   if (!printerFlags.shouldPrintGenericOpForm()) {
     // Check to see if this is a known operation. If so, use the registered
     // custom printer hook.
     if (auto opInfo = op->getRegisteredInfo()) {
+      StringRef name = op->getName().getStringRef();
+      if (llvm::count(name, '.') > 1)
+        opInfo->printAssembly(op, *this, "");
+      else
         opInfo->printAssembly(op, *this, defaultDialectStack.back());
       return;
     }
     // Otherwise try to dispatch to the dialect, if available.
     if (Dialect *dialect = op->getDialect()) {
       if (auto opPrinter = dialect->getOperationPrinter(op)) {
         // Print the op name first.
         StringRef name = op->getName().getStringRef();
         name.consume_front((defaultDialectStack.back() + ".").str());