llvm-project

84564e10 - [flang][NFC] Cache derived type translation in lowering (#80179)

[flang][NFC] Cache derived type translation in lowering (#80179) Derived type translation is proving expensive in modern fortran apps with many big derived types with dozens of components and parents. Extending the cache that prevent recursion is proving to have little cost on apps with small derived types and significant gain (can divide compile time by 2) on modern fortran apps. It is legal since the cache lifetime is less than the MLIRContext lifetime that owns the cached mlir::Type. Doing so also exposed that the current caching was incorrect, the type symbol is the same for kind parametrized derived types regardless of the kind parameters. Instances with different kinds should lower to different MLIR types. See added test. Using the type scopes fixes the problem.