`TensorLambdaArgument` uses an `llvm::MutableArrayRef` to reference
the tensor values. This prevents temporary tensors from being used as
an argument, due to the data of the `TensorLambdaArgument` being
accessed after the destruction of the temporary.
This patch changes the type of the data field of
`TensorLambdaArgument` from `llvm::MutableArrayRef` to `std::vector`
and causes input data to be copied in order to guarantee that all data
remains available until invocation of the destructor.
All results in code compiled by zamacompiler are passed as return
values, which means that all tensors passed as function arguments are
constant inputs that are never written.
This patch changes the arguments used as data pointers for input
tensors in `JITLambda::Arguments::setArg()` from `void*` to `const
void*` to emphasize their use as inputs and to allow for constant
arrays to be passed as function inputs.
This adds a new overload for `JitCompilerEngine::Lambda::operator()`,
returning a result wrapped in a `std::unique_ptr<LambdaArgument>` with
meta information about the result. This allows for generic invocations
of JitCompilerEngine::Lambda::operator(), where the result type is
unknown before the invocation.
This commit contains several incremental improvements towards a clear
interface for lambdas:
- Unification of static and JIT compilation by using the static
compilation path of `CompilerEngine` within a new subclass
`JitCompilerEngine`.
- Clear ownership for compilation artefacts through
`CompilationContext`, making it impossible to destroy objects used
directly or indirectly before destruction of their users.
- Clear interface for lambdas generated by the compiler through
`JitCompilerEngine::Lambda` with a templated call operator,
encapsulating otherwise manual orchestration of `CompilerEngine`,
`JITLambda`, and `CompilerEngine::Argument`.
- Improved error handling through `llvm::Expected<T>` and proper
error checking following the conventions for `llvm::Expected<T>`
and `llvm::Error`.
Co-authored-by: youben11 <ayoub.benaissa@zama.ai>
As we store the funcname for the entrypoint for later use, a pointer
might point to some random memory when used as there is no special
management for that name at the higher levels.
Composing error messages for `llvm::Error` is either done by using
`llvm::createStringError()` with an appropriate format string and
arguments or by writing to a `std::string`-backed
`llvm::raw_string_ostream` and passing the result to
`llvm::make_error<llvm::StringError>()` verbatim.
The new class `StreamStringError` encapsulates the latter solution
into a class with an appropriate stream operator and implicit cast
operators to `llvm::Error` and `llvm::Expected`.
Example usage:
llvm::Error foo(int i, size_t s, ...) {
...
if(...) {
return StreamStringError()
<< "Some error message with an integer: "
<< i << " and a size_t: " << s;
}
...
}
This replaces the default FHE circuit constrains (maximum encrypted
integer width of 7 bits and a Minimal Arithmetic Noise Padding of 10
with the results of the `MaxMANP` pass, which determines these values
automatically from the input program.
Since the maximum encrypted integer width and the maximum value for
the Minimal Arithmetic Noise Padding can only be derived from HLFHE
operations, the circuit constraints are determined automatically by
`zamacompiler` only if the option `--entry-dialect=hlfhe` was
specified.
For lower-level dialects, `zamacompiler` has been provided with the
options `--assume-max-eint-precision=...` and `--assume-max-manp=...`
that allow a user to specify the values for the maximum required
precision and maximum values for the Minimal Arithmetic Noise Padding.
The new option --acion=dump-hlfhe-manp invokes the Minimal Arithmetic
Noise Padding Analysis pass based on the squared 2-norm metric from
`lib/Dialect/HLFHE/Analysis/MANP.cpp` and dumps the module afterwards
with an extra attribute `MANP` for each HLFHE operation.
This refactoring commit restructures the compilation pipeline of
`zamacompiler`, such that it is possible to enter and exit the
pipeline at different points, effectively defining the level of
abstraction at the input and the required level of abstraction for the
output.
The entry point is specified using the `--entry-dialect`
argument. Valid choices are:
`--entry-dialect=hlfhe`: Source contains HLFHE operations
`--entry-dialect=midlfhe`: Source contains MidLFHE operations
`--entry-dialect=lowlfhe`: Source contains LowLFHE operations
`--entry-dialect=std`: Source does not contain any FHE Operations
`--entry-dialect=llvm`: Source is in LLVM dialect
The exit point is defined by an action, specified using --action.
`--action=roundtrip`:
Parse the source file to in-memory representation and immediately
dump as text without any processing
`--action=dump-midlfhe`:
Lower source to MidLFHE and dump result as text
`--action=dump-lowlfhe`:
Lower source to LowLFHE and dump result as text
`--action=dump-std`:
Lower source to only standard MLIR dialects (i.e., all FHE
operations have already been lowered)
`--action=dump-llvm-dialect`:
Lower source to MLIR's LLVM dialect (i.e., the LLVM dialect, not
LLVM IR)
`--action=dump-llvm-ir`:
Lower source to plain LLVM IR (i.e., not the LLVM dialect, but
actual LLVM IR)
`--action=dump-optimized-llvm-ir`:
Lower source to plain LLVM IR (i.e., not the LLVM dialect, but
actual LLVM IR), pass the result through the LLVM optimizer and
print the result.
`--action=dump-jit-invoke`:
Execute the full lowering pipeline to optimized LLVM IR, JIT
compile the result, invoke the function specified in
`--jit-funcname` with the parameters from `--jit-args` and print
the functions return value.
The function `getV0Parameter()` returns a pointer to a static array,
which is not intended to be mutable. Reflect this in the return type
of the function.
Replace the macros `LOG_VERBOSE` and `LOG_ERROR` with C++-style
streams retrieved through `log_verbose()` and `log_error()`. This
aligns with the `MLIR` infrastructure and avoids pollution of the
global namespace through a common header file in subsequent
refactoring commits splitting the functionality of `src/main.cpp` into
multiple files.
