[Mlir-commits] [mlir] [mlir] Add dialect hooks for registering custom type and attribute alias printers (PR #173091)

[Fabian Mora]

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@@ -1799,6 +1812,30 @@ class OpAsmDialectInterface
     return AliasResult::NoAlias;
   }
 
+  /// Hooks for registering alias printers for types and attributes. These
+  /// printers are invoked when printing types or attributes of the given
+  /// TypeID. Printers are invoked in the order they are registered, and the
+  /// first one to print an alias is used.
+  /// The precedence of these printers is as follow:
+  /// 1. The type and attribute aliases returned by `getAlias`.
+  /// 2. Dialect-specific alias printers registered here.
+  /// 3. The type and attribute printers.
+  /// The boolean argument to the printer indicates whether the stripped form
+  /// of the type or attribute is being printed.
+  /// NOTE: This mechanism caches the printed object, therefore the printer
+  /// must always produce the same output for the same input.
+  using AttributeAliasPrinter =
+      llvm::function_ref<void(Attribute, AsmPrinter &, bool)>;
+  using InsertAttrAliasPrinter =
+      llvm::function_ref<void(TypeID, AttributeAliasPrinter)>;
+  virtual void registerAttrAliasPrinter(InsertAttrAliasPrinter insertFn) const {
+  }
+  using TypeAliasPrinter = llvm::function_ref<void(Type, AsmPrinter &, bool)>;
+  using InsertTypeAliasPrinter =
+      llvm::function_ref<void(TypeID, TypeAliasPrinter)>;
+  virtual void registerTypeAliasPrinter(InsertTypeAliasPrinter insertFn) const {
+  }
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fabianmcg wrote:

Note, that the current mechanism https://github.com/llvm/llvm-project/blob/main/mlir/lib/IR/AsmPrinter.cpp#L1223-L1233 is not scoped to its own entities.

The pattern you describe can be included, but it wouldn't help the `ptr` situation. So perhaps it makes more sense to settle the `!llvm.ptr` discussion first, and then comeback to this.

https://github.com/llvm/llvm-project/pull/173091