This adds a new dialect called `Optimizer` with operations related to
the Concrete Optimizer. Currently, there is only one operation
`optimizer.partition_frontier` that can be inserted between a producer
and a consumer which belong to different partitions computed by the
optimizer. The purpose of this operation is to preserve explicit key
changes from the invocation of the optimizer on high-level dialects
(i.e., FHELinalg / FHE) until the IR is provided with actual
references to keys in low-level dialects (i.e., TFHE).
The `TypeInference` dialect provides three operations.
The operation `TypeInference.propagate_downwards` respresents a type
barrier, which is supposed to forward the type of its operand as its
result type during type inference.
The operation `TypeInference.propagate_upwards` also respresents a
type barrier, but is supposed to forward the type of its result as the
type for its operand during type inference.
The operation `TypeInference.unresolved_conflict` can be used as a
marker when two different types have beed inferred for a value (e.g.,
one type during forward dataflow analysis and the other during
backward dataflow analysis)
This commit:
+ Adds support for a protocol which enables inter-op between concrete,
tfhe-rs and potentially other contributors to the fhe ecosystem.
+ Gets rid of hand-made serialization in the compiler, and
client/server libs.
+ Refactors client/server libs to allow more pre/post processing of
circuit inputs/outputs.
The protocol is supported by a definition in the shape of a capnp file,
which defines different types of objects among which:
+ ProgramInfo object, which is a precise description of a set of fhe
circuit coming from the same compilation (understand function type
information), and the associated key set.
+ *Key objects, which represent secret/public keys used to
encrypt/execute fhe circuits.
+ Value object, which represent values that can be transferred between
client and server to support calls to fhe circuits.
The hand-rolled serialization that was previously used is completely
dropped in favor of capnp in the whole codebase.
The client/server libs, are refactored to introduce a modular design for
pre-post processing. Reading the ProgramInfo file associated with a
compilation, the client and server libs assemble a pipeline of
transformers (functions) for pre and post processing of values coming in
and out of a circuit. This design properly decouples various aspects of
the processing, and allows these capabilities to be safely extended.
In practice this commit includes the following:
+ Defines the specification in a concreteprotocol package
+ Integrate the compilation of this package as a compiler dependency
via cmake
+ Modify the compiler to use the Encodings objects defined in the
protocol
+ Modify the compiler to emit ProgramInfo files as compilation
artifact, and gets rid of the bloated ClientParameters.
+ Introduces a new Common library containing the functionalities shared
between the compiler and the client/server libs.
+ Introduces a functional pre-post processing pipeline to this common
library
+ Modify the client/server libs to support loading ProgramInfo objects,
and calling circuits using Value messages.
+ Drops support of JIT.
+ Drops support of C-api.
+ Drops support of Rust bindings.
Co-authored-by: Nikita Frolov <nf@mkmks.org>
