Previously we only check that each field is of the correct
mlir::Attribute subclass. This commit enhances to also consider
the attribute's types, by leveraging the constraints already
encoded in TableGen attribute definitions.
Reviewed By: rsuderman
Differential Revision: https://reviews.llvm.org/D72162
BitEnumAttr is a mechanism for modelling attributes whose value is
a bitfield. It should not be scoped to the SPIR-V dialect and can
be used by other dialects too.
This CL is mostly shuffling code around and adding tests and docs.
Functionality changes are:
* Fixed to use `getZExtValue()` instead of `getSExtValue()` when
getting the value from the underlying IntegerAttr for a case.
* Changed to auto-detect whether there is a case whose value is
all bits unset (i.e., zero). If so handle it specially in all
helper methods.
PiperOrigin-RevId: 277964926
Similar to enum, added a generator for structured data. This provide Dictionary that stores a fixed set of values and guarantees the values are valid. It is intended to store a fixed number of values by a given name.
PiperOrigin-RevId: 266437460
In ODS, right now we use StringAttrs to emulate enum attributes. It is
suboptimal if the op actually can and wants to store the enum as a
single integer value; we are paying extra cost on storing and comparing
the attribute value.
This CL introduces a new enum attribute subclass that are backed by
IntegerAttr. The downside with IntegerAttr-backed enum attributes is
that the assembly form now uses integer values, which is less obvious
than the StringAttr-backed ones. However, that can be remedied by
defining custom assembly form with the help of the conversion utility
functions generated via EnumsGen.
Choices are given to the dialect writers to decide which one to use for
their enum attributes.
PiperOrigin-RevId: 255935542
Enum attributes can be defined using `EnumAttr`, which requires all its cases
to be defined with `EnumAttrCase`. To facilitate the interaction between
`EnumAttr`s and their C++ consumers, add a new EnumsGen TableGen backend
to generate a few common utilities, including an enum class, `llvm::DenseMapInfo`
for the enum class, conversion functions from/to strings.
This is controlled via the `-gen-enum-decls` and `-gen-enum-defs` command-line
options of `mlir-tblgen`.
PiperOrigin-RevId: 252209623
Currently predicates are written with positional placeholders `{N}` and rely on
`formatv` as the engine to do substitution. The problem with this approach is that
the definitions of those positional placeholders are not consistent; they are
entirely up to the defining predicate of question. For example, `{0}` in various
attribute constraints is used to mean the attribute, while it is used to main the
builder for certain attribute transformations. This can become very confusing.
This CL introduces `tgfmt` as a new mechanism to better support for predicate and
rewrite rule specification. Instead of entirely relying on positional placeholders,
`tgfmt` support both positional and special placeholders. The former is used for
DAG operands. The latter, including $_builder, $_op, $_self, are used as special
"hooks" to entities in the context. With this, the predicate and rewrite rules
specification can be more consistent is more readable.
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PiperOrigin-RevId: 243249671
Lei Zhang