The dialect-specific cast between builtin (ex-standard) types and LLVM
dialect types was introduced long time before built-in support for
unrealized_conversion_cast. It has a similar purpose, but is restricted
to compatible builtin and LLVM dialect types, which may hamper
progressive lowering and composition with types from other dialects.
Replace llvm.mlir.cast with unrealized_conversion_cast, and drop the
operation that became unnecessary.
Also make unrealized_conversion_cast legal by default in
LLVMConversionTarget as the majority of convesions using it are partial
conversions that actually want the casts to persist in the IR. The
standard-to-llvm conversion, which is still expected to run last, cleans
up the remaining casts standard-to-llvm conversion, which is still
expected to run last, cleans up the remaining casts
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D105880
It is no longer necessary to also convert other "standard" ops along with the
complex dialect: the element types are now built-in integers or floating point
types, and the top-level cast between complex and struct is automatically
inserted and removed in progressive lowering.
Reviewed By: herhut
Differential Revision: https://reviews.llvm.org/D95625
Alex Zinenko