Translations performed by mlir-translate only have MLIR on one end.
MLIR-to-MLIR conversions (including dialect changes) should be treated as
passes and run by mlir-opt. Individual translations should not care about
reading or writing MLIR and should work on in-memory representation of MLIR
modules instead. Split the TranslateFunction interface and the translate
registry into two parts: "from MLIR" and "to MLIR".
Update mlir-translate to handle both registries together by wrapping
translation functions into source-to-source convresions. Remove MLIR parsing
and writing from individual translations and make them operate on Modules
instead. This removes the need for individual translators to include
tools/mlir-translate/mlir-translate.h, which can now be safely removed.
Remove mlir-to-mlir translation that only existed as a registration example and
use mlir-opt instead for tests.
PiperOrigin-RevId: 222398707
The mlir-translate tool is expected to discover individual translations at link
time. These translations must register themselves and may need the utilities
that are currently defined in mlir-translate.cpp for their entry point
functions. Since mlir-translate is linking against individual translations,
the translations cannot link against mlir-translate themselves. Extract out
the utilities into a separate "Translation" library to avoid the potential
dependency cycle. Individual translations link to that library to access
TranslateRegistration. The mlir-translate tool links to individual translations
and to the "Translation" library because it needs the utilities as well.
The main header of the new library is located in include/mlir/Translation.h to
make it easily accessible by translators. The rationale for putting it to
include/mlir rather than to one of its subdirectories is that its purpose is
similar to that of include/mlir/Pass.h so it makes sense to put them at the
same level.
PiperOrigin-RevId: 222398617
Jacques Pienaar