torch-mlir/python/npcomp/compiler/pytorch/backend/refjit.py

131 lines
4.3 KiB
Python

# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
import os
import torch
from mlir.ir import *
from mlir.passmanager import *
from npcomp.compiler.generic.backend import refjit as refjit_backend
from npcomp.compiler.utils import logging
__all__ = [
"is_enabled",
"CompilerBackend",
]
# The set of passes that lowers from a TorchScript object graph representation
# to a module semantics where symbols correspond to dotted paths into the
# module.
OBJECT_GRAPH_LOWERING_PASSES = (
"torch-globalize-pipeline",
# symbol-dce is currently needed for correctness, as we don't have a lowering
# in the backend for torch.global_slot's.
# Torch usually inserts a few unused global slots that are otherwise
# bothersome because we don't currently have a lowering for them.
# TODO: Support global slots in backends.
"symbol-dce",
"torch-adjust-calling-conventions",
)
TORCH_TO_TCF_PASSES = (
"func(aten-recognize-kernels)",
"func(convert-aten-to-tcf)",
"numpy-public-functions-to-tensor",
"canonicalize",
)
# Re-export.
is_enabled = refjit_backend.is_enabled
class TorchJitModuleInvoker(refjit_backend.JitModuleInvoker):
"""Allows torch.Tensor inputs to be passed to module invocations."""
def __getitem__(self, function_name: str):
numpy_invoke = super().__getitem__(function_name)
def invoke(*args):
args = tuple(
arg.numpy() if isinstance(arg, torch.Tensor) else arg for arg in args)
return numpy_invoke(*args)
return invoke
class CompilerBackend:
"""Main entry-point for the backend."""
def __init__(self):
super().__init__()
self._refjit = refjit_backend.get_refjit()
self._debug = logging.debug_enabled()
def compile(self, imported_module: Module):
"""Compiles an imported module, with a flat list of functions.
Args:
imported_module: The MLIR module consisting of funcs in the torch
dialect.
Returns:
An opaque, backend specific module object that can be passed to load.
The object may actually be something more specific to the backend (i.e.
for IREE, it is a serialized VM flatbuffer) but the contract is that
it is operated on by methods on this class.
"""
with imported_module.context as context:
if self._debug:
logging.debug("Initial PyTorch IR:\n{}", imported_module)
# Frontend.
pipeline_str = ",".join(TORCH_TO_TCF_PASSES)
if self._debug:
logging.debug("Running Torch->TCF pipeline '{}'", pipeline_str)
pm = PassManager.parse(pipeline_str)
pm.run(imported_module)
if self._debug:
logging.debug("TCF IR:\n{}", imported_module)
# Backend.
# Note that this is a separate pass manager purely to aid in debugging.
pm = PassManager()
self._refjit.build_backend_compilation_pipeline(pm)
pm.run(imported_module)
if self._debug:
logging.debug("Backend IR:\n{}", imported_module)
jit_module = self._refjit.JITModule.from_compiled_module(
imported_module, refjit_backend.get_runtime_libs())
return jit_module
def compile_object_graph(self, imported_module: Module):
"""Compiles an imported module, with TorchScript object graph semantics.
Args:
imported_module: The MLIR module consisting of IR as imported by the
torch_mlir.import_module
Returns:
An opaque, backend specific module object that can be passed to load.
The object may actually be something more specific to the backend (i.e.
for IREE, it is a serialized VM flatbuffer) but the contract is that
it is operated on by methods on this class.
"""
with imported_module.context as context:
if self._debug:
logging.debug("Initial PyTorch object graph IR:\n{}", imported_module)
# Frontend.
pipeline_str = ",".join(OBJECT_GRAPH_LOWERING_PASSES)
if self._debug:
logging.debug(
"Running Torch object graph lowering pipeline '{}'", pipeline_str)
pm = PassManager.parse(pipeline_str)
pm.run(imported_module)
return self.compile(imported_module)
def load(self, jit_module) -> TorchJitModuleInvoker:
"""Loads a compiled artifact into the runtime."""
return TorchJitModuleInvoker(jit_module)