This makes the bytecode reader/writer work on big-endian platforms.
The only problem was related to encoding of multi-byte integers,
where both reader and writer code make implicit assumptions about
endianness of the host platform.
This fixes the current test failures on s390x, and in addition allows
to remove the UNSUPPORTED markers from all other bytecode-related
test cases - they now also all pass on s390x.
Also adding a GFAIL_SKIP to the MultiModuleWithResource unit test,
as this still fails due to an unrelated endian bug regarding
decoding of external resources.
Differential Revision: https://reviews.llvm.org/D153567
Reviewed By: mehdi_amini, jpienaar, rriddle
Some tests still pass even though we don't claim big-endian support. Using
UNSUPPORTED is a better indicator than XFAIL that we don't guarantee that
the tests work.
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
