Resources are encoded in two separate sections similarly to
attributes/types, one for the actual data and one for the data
offsets. Unlike other sections, the resource sections are optional
given that in many cases they won't be present. For testing,
bytecode serialization is added for DenseResourceElementsAttr.
Differential Revision: https://reviews.llvm.org/D132729
Dialects can opt-in to providing custom encodings by implementing the
`BytecodeDialectInterface`. This interface provides hooks, namely
`readAttribute`/`readType` and `writeAttribute`/`writeType`, that will be used
by the bytecode reader and writer. These hooks are provided a reader and writer
implementation that can be used to encode various constructs in the underlying
bytecode format. A unique feature of this interface is that dialects may choose
to only encode a subset of their attributes and types in a custom bytecode
format, which can simplify adding new or experimental components that aren't
fully baked.
Differential Revision: https://reviews.llvm.org/D132498
This commit adds a new bytecode serialization format for MLIR.
The actual serialization of MLIR to binary is relatively straightforward,
given the very very general structure of MLIR. The underlying basis for
this format is a variable-length encoding for integers, which gets heavily
used for nearly all aspects of the encoding (given that most of the encoding
is just indexing into lists).
The format currently does not provide support for custom attribute/type
serialization, and thus always uses an assembly format fallback. It also
doesn't provide support for resources. These will be added in followups,
the intention for this patch is to provide something that supports the
basic cases, and can be built on top of.
https://discourse.llvm.org/t/rfc-a-binary-serialization-format-for-mlir/63518
Differential Revision: https://reviews.llvm.org/D131747
Jacques Pienaar