Multi-Level IR Compiler Framework

Deprecations & Current Refactoring

This page collects current deprecations in MLIR of API and features we intend to remove soon, as well as large refactoring an migration on-going. We try to list these here for the purpose of helping downstream users keeping up with MLIR development.


preloadDialectInContext has been deprecated for >1y and will be removed

If you have an mlir-opt tool and you’re still depending on preloadDialectInContext, you need to revisit your pipeline. This option used with mlir-opt is hiding issues with the pipeline, and indications of missing getDependentDialects(). Discussion on Discourse

Migrating mlir-opt-like tools to use MlirOptMainConfig

If your mlir-opt-like tool is using the MlirOptMain(int argc, char **argv, ...) entry point you won’t be affected, otherwise, see the Discussion on Discourse

Use the free function variants for dyn_cast/cast/isa/…

When casting attributes or type, use the free functions variants, e.g., dyn_cast<T>(x), isa<T>(x), etc. Use of the cast methods variants (e.g., x.dyn_cast<T>()) should be avoided in new code as we’ll remove these methods in the future. Discussion on Discourse

Port uses of LLVM Dialect to opaque pointers

LLVM 17 has stopped officially supporting typed pointers and MLIRs LLVM Dialect will follow suit soon by removing them. Users of the LLVM Dialect must switch to using opaque pointers and stop relying on pointers having an element type. See the initial PSA post for precise instructions and timeline.

On-going Refactoring

Past Deprecation and Refactoring