test_onnx_export.py

# Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
#
# See LICENSE for license information.

"""
This file contains tests for exporting TransformerEngine models to ONNX.

The purpose of these tests is validation that TE models are converted to their correct ONNX
representation. Toward this end, each test captures the output of a TE module forward pass,
converts the TE module to ONNX, and uses ONNX Runtime (ORT) to execute the ONNX graph and
validate the output against TE's output.

Until FP8 is introduced to the ONNX standard, FP8 QuantizeLinear/DequantizeLinear is implemented
using custom ORT operations.

To run many repetitive tests use pytest-loop:
    $ python3 -m pip install pytest-loop
    $ pytest --loop 1000 tests/pytorch/test_onnx_export.py::test_export_layernorm

For reproducability use: torch.manual_seed(0)
"""


import os
import tempfile
import pytest
import warnings
import numpy as np
import onnxruntime as ort
import torch
from torch import nn as nn
from typing import Union, Tuple
import transformer_engine.pytorch as te
from transformer_engine.common import recipe
import transformer_engine_extensions as tex
from transformer_engine.pytorch.cpp_extensions import gemm, fp8_gemm, fp8_gelu, cast_to_fp8, cast_from_fp8
from transformer_engine.pytorch.module import get_workspace
import transformer_engine.pytorch.cpp_extensions as texcpp
import transformer_engine.pytorch.softmax as softmax_defs
from transformer_engine.pytorch.utils import get_default_init_method
from transformer_engine.pytorch.export import is_in_onnx_export_mode
from transformer_engine.pytorch.fp8 import is_fp8_available

# Global test configuration knobs.

# Enable this to serialize test inputs and outputs to file (as a Polygraphy RunResults instance).
SAVE_TEST_IO = False
if SAVE_TEST_IO:
    from polygraphy.json import save_json
    from polygraphy.comparator import RunResults

# The directory where generated ONNX test models are stored.
NVTE_TEST_ARTIFACTS_DIR = os.environ.get('NVTE_TEST_ARTIFACTS_DIR')
NVTE_TEST_ARTIFACTS_DIR = NVTE_TEST_ARTIFACTS_DIR or os.path.join(tempfile.gettempdir(), "./gen_onnx_models")


# The directory where this file is stored.
TESTS_DIR = os.path.dirname(os.path.abspath(__file__))

# ScaledUpperTriangMaskedSoftmax is exported via ONNX::Trilu which was introduced in opset 14.
TRILU_OPSET = 14
# Opset used in the ONNX files generated by the tests.
OPSET = 17
assert OPSET >= TRILU_OPSET

# Shared library implementing custom FP8 Q/DQ operators for ONNX Runtime (ORT).
ORT_CUSTOM_OPS_LIB = os.path.join(TESTS_DIR, "./libcustom_ort_fp8_qdq_ops.so")

fp8_available, reason_for_no_fp8 = is_fp8_available()
skip_FP8 = pytest.mark.skipif(not fp8_available, reason=reason_for_no_fp8)

def create_fp8_recipe():
    return recipe.DelayedScaling(margin=0, interval=1, fp8_format=recipe.Format.E4M3)


def do_export(
    model: torch.nn.Module,
    inp: torch.Tensor,
    fname: str,
    use_fp8: bool=True,
    opset: int=OPSET,
    input_names: list=["input"],
    output_names: list=["output"],
):
    """Export to ONNX"""
    fp8_recipe = create_fp8_recipe()

    with torch.inference_mode(), te.fp8_autocast(enabled=use_fp8, fp8_recipe=fp8_recipe), warnings.catch_warnings():
        warnings.filterwarnings(
            action='ignore',
            category=torch.jit.TracerWarning,
            module=r'.*'
        )

        model.cuda().eval()
        os.makedirs(NVTE_TEST_ARTIFACTS_DIR, exist_ok=True)
        fname = os.path.join(NVTE_TEST_ARTIFACTS_DIR, fname)
        inps = inp if isinstance(inp, list) or isinstance(inp, tuple) else (inp,)
        with te.onnx_export(True):
            torch.onnx.export(
                model,
                inps,
                fname,
                verbose=True,
                opset_version=opset,
                input_names=input_names,
                output_names=output_names,
                # Do not constant-fold because torch.onnx incorrectly folds
                # layer_norm(data, scale=add(gamma,1)) to layer_norm(data, scale=gamma)
                # when we use LN with zero-centered gamma.
                do_constant_folding=False,
                operator_export_type=torch.onnx.OperatorExportTypes.ONNX_FALLTHROUGH)


def to_numpy(tensor):
    return tensor.cpu().numpy()


def set_layer_scale(module: torch.nn.Module, scale: float, num_gemms: int):
    """Initialize the FP8 quantization scales in module"""
    NB_SCALES_PER_GEMM = 3  # One scale per: input, weights, and output GEMM tensors.
    nb_total_scales = num_gemms * NB_SCALES_PER_GEMM
    module.fp8_init(num_gemms)
    module.fp8_meta["scaling_fwd"].scale = torch.ones(
        nb_total_scales, dtype=torch.float32, device="cuda") / scale
    module.fp8_meta["scaling_fwd"].scale_inv = torch.ones(
        nb_total_scales, dtype=torch.float32, device="cuda") * scale


def te_infer(model: torch.nn.Module, inps: Union[Tuple[torch.tensor], torch.tensor], is_fp8: bool):
    """Transformer Engine forward prpoagtation.

    Return results after copying to the CPU and converting to numpy.
    """
    fp8_recipe = create_fp8_recipe()
    with torch.inference_mode(), te.fp8_autocast(enabled=is_fp8, fp8_recipe=fp8_recipe), warnings.catch_warnings():
        te_outputs = model(*inps if isinstance(inps, tuple) else (inps,))
        if not isinstance(te_outputs, tuple):
            te_outputs = (te_outputs,)
        te_outputs_np = [to_numpy(te_output) for te_output in te_outputs]
        return te_outputs_np


def validate_result(
    fname: str,
    inps: Union[Tuple[torch.Tensor], torch.Tensor],
    model: torch.nn.Module,
    atol: float=1.e-8, # np.isclose default atol
    rtol: float=1.e-5, # np.isclose default rtol
    max_errors_printed: int=10,
    is_fp8: bool=False,
    allow_cnt_errors: int=0,
    input_names: list=["input"],
    output_names: list=["output"],
    infer_ort=True
):
    """Compare the outputs of a Transformer Engine (TE) module vs the outputs of its ONNX
    representation using ONNX Runtime (ORT) and ensure they are close.

    The purpose of the output comparison is to validate that TE models are converted to
    their correct ONNX representation by testing that TE and ORT outputs match within some
    small threshold (allowing for finite precision errors).

    Argument `allow_cnt_errors` reduces test failure noise due to spurious errors by ignoring,
    a very small number (0-3) of outliers. This is fine to do because these outliers are due to
    small kernel implementation differences between TE and ORT and do not imply an incorrect ONNX
    representation (the tests assume both ORT or TE kernels are correct).
    """

    def create_ort_session(fname: str, is_fp8: bool):
        def load_custom_ops(session_opts: ort.SessionOptions):
            """For FP8 validation with ORT we need to load our custom FP8 Q/DQ extension."""
            if not os.path.exists(ORT_CUSTOM_OPS_LIB):
                raise FileNotFoundError(f"Unable to find {ORT_CUSTOM_OPS_LIB}")
            session_opts.register_custom_ops_library(ORT_CUSTOM_OPS_LIB)
            print("registered custom FP8 Q/DQ ops!")

        """Create an ONNX Runtime session for validation."""
        kwargs = {}
        if is_fp8:
            sess_options = ort.SessionOptions()
            load_custom_ops(sess_options)
            kwargs["sess_options"] = sess_options

        s = ort.InferenceSession(fname, **kwargs)
        return s

    def create_ort_input_dict(session, inps):
        inp_dict = {}
        if isinstance(inps, tuple) or isinstance(inps, list):
            nonetype_inputs = 0
            for idx, inp in enumerate(inps):
                if inp is None:
                    nonetype_inputs += 1
                    continue
                inp_dict[session.get_inputs()[idx - nonetype_inputs].name] = to_numpy(inp)
        else:
            inp_dict[session.get_inputs()[0].name] = to_numpy(inps)
        return inp_dict

    def serialize_inputs_outputs(fname, inputs, inputs_names, te_outputs, output_names):
        if not SAVE_TEST_IO:
            return
        inputs = inputs if isinstance(inputs, list) or isinstance(inputs, tuple) else (inputs,)
        named_inputs = zip(inputs_names, inputs)
        input_data = [{k: to_numpy(v) for k, v in named_inputs if v is not None}]
        json_fname = fname[:-len(".onnx")] + "_inputs.json"
        save_json(input_data, json_fname, description="custom input data")

        if "bf16" in fname:
            return
        json_fname = fname[:-len(".onnx")] + "_output.json"
        named_outputs = zip(output_names, te_outputs)
        output_data = dict()
        for out_name, outp in named_outputs:
            if outp is not None:
                assert out_name not in output_data
                output_data[out_name] = outp
        custom_outputs = RunResults()
        custom_outputs.add([output_data], runner_name="custom_runner")
        custom_outputs.save(json_fname)

    def compare_outputs(onnx_outputs, te_outputs):
        """ Compare ORT and TE outputs."""
        assert len(onnx_outputs) == len(te_outputs)
        # Compare ORT and PyTorch outputs.
        for onnx_output, te_output in zip(onnx_outputs, te_outputs):
            # np.isclose: abs(a - b) <= (atol + rtol * abs(b))
            ac = ~np.isclose(onnx_output, te_output, atol=atol, rtol=rtol)
            mismatches = ac.nonzero()
            mismatched_ids = [loc for loc in zip(*mismatches)]
            if mismatched_ids:
                # Log some information in case of error.
                print("*" * 100)
                nb_errors = len(mismatched_ids)
                nb_vals = min(nb_errors, max_errors_printed)
                print(f"Detected {nb_errors} diverging values (output shape={onnx_output.shape})")
                print(f"Showing first {nb_vals} errors (ONNX -- TE):")
                abs_err = np.abs(onnx_output - te_output)
                errors = abs_err[mismatches]
                for loc in mismatched_ids[:nb_vals]:
                    ref = te_output[loc]
                    print(f"{onnx_output[loc]} -- {te_output[loc]} err={abs_err[loc]} > {atol + rtol * abs(ref)}")
                print(f"Max error: {np.max(errors)}")
                if nb_errors > allow_cnt_errors:
                    raise ValueError(f"Output validation of {fname} failed with {nb_errors} errors")

    # Run ORT session and TE model.
    fname = os.path.join(NVTE_TEST_ARTIFACTS_DIR, fname)
    te_outputs = te_infer(model, inps, is_fp8)
    if infer_ort:
        ort_s = create_ort_session(fname, is_fp8)
        input_feed = create_ort_input_dict(ort_s, inps)
        onnx_outputs = ort_s.run(None, input_feed=input_feed)
        compare_outputs(onnx_outputs, te_outputs)
    serialize_inputs_outputs(fname, inps, input_names, te_outputs, output_names)


def create_meta(scale_factor: float, size: int=1):
    meta = tex.FP8TensorMeta()
    meta.amax_history = torch.zeros(1, size, dtype=torch.float32, device="cuda")
    meta.scale_inv = torch.ones(size, dtype=torch.float32, device="cuda") / scale_factor
    meta.scale = torch.ones(size, dtype=torch.float32, device="cuda") * scale_factor
    return meta


def dtype2str(dtype: torch.dtype):
    return {
        torch.float32: "_fp32",
        torch.float16: "_fp16",
        torch.bfloat16: "_bf16",
    }[dtype]


def as_te_type(dtype: torch.dtype):
    return {
        torch.float32: tex.DType.kFloat32,
        torch.float16: tex.DType.kFloat16,
        torch.bfloat16: tex.DType.kBFloat16,
    }[dtype]


def get_attn_mask_str(use_mask, attn_mask_type):
    # See FusedScaleMaskSoftmax::forward_fused_softmax for logic behind names.
    if attn_mask_type is None:
        return "_mask" if use_mask else "_no-mask"
    attn_mask_str = "_padding-no-mask"
    attn_mask_str = "_causal-mask" if attn_mask_type == "causal" else attn_mask_str
    attn_mask_str = "_padding-mask" if use_mask and attn_mask_type == "padding" else attn_mask_str
    return attn_mask_str


@skip_FP8
@pytest.mark.parametrize("scale_factor, atol", [
    (1, 1e-7),
    (224, 1e-7)
])
@pytest.mark.parametrize("precision", [torch.float32, torch.float16])
def test_export_cast_ops(scale_factor: float, atol: float, precision: torch.dtype):
    class TestFP8_QDQ(nn.Module):
        def __init__(self):
            super().__init__()
            self.fp8_tensor = 0
            self.meta = create_meta(scale_factor)
            self.highprec_type = as_te_type(precision)
            self.fp8_type = tex.DType.kFloat8E4M3

        def forward(self, inp):
            ret = cast_to_fp8(
                inp,
                self.meta,
                self.fp8_tensor,
                self.fp8_type)

            ret = cast_from_fp8(
                ret,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                self.highprec_type)
            return ret

    # Set dimensions (these are arbitrary).
    in_features = 64
    hidden_size = 256
    inp = torch.randn(hidden_size, in_features, device="cuda", dtype=precision)
    high_prec_str = dtype2str(precision)
    fname = f"te.cast_fp8_{scale_factor}{high_prec_str}.onnx"
    model = TestFP8_QDQ()
    do_export(model, inp, fname)
    validate_result(fname, inp, model, atol=atol, is_fp8=True)


@skip_FP8
@pytest.mark.parametrize("scale_factor", [448])
@pytest.mark.parametrize(
    "precision,     atol", [
    [torch.float32, 1e-5],
    [torch.float16, 1e-5]
])
def test_export_gelu_fp8(scale_factor: float, precision: torch.dtype, atol: float):
    class TestFP8_Gelu(nn.Module):
        def __init__(self):
            super().__init__()
            self.fp8_tensor = 0
            self.meta = create_meta(scale_factor)
            self.highprec_type = as_te_type(precision)
            self.fp8_type = tex.DType.kFloat8E4M3

        def forward(self, inp):
            ret = fp8_gelu(
                inp,
                self.meta,
                self.fp8_tensor,
                self.fp8_type)
            ret = cast_from_fp8(
                ret,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                self.highprec_type)
            return ret

    # Set dimensions (these are arbitrary).
    in_features = 64
    hidden_size = 256
    inp = torch.randn(hidden_size, in_features, device="cuda", dtype=precision)
    high_prec_str = dtype2str(precision)
    fname = f"te.gelu_fp8_{scale_factor}{high_prec_str}.onnx"
    model = TestFP8_Gelu()
    do_export(model, inp, fname)
    validate_result(fname, inp, model, rtol=0, atol=atol, is_fp8=True, allow_cnt_errors=2)


@pytest.mark.parametrize("scale_factors",
    [(224, 224,),
])
@pytest.mark.parametrize(
    "precision,     use_fp8, use_bias, use_gelu", [
    (torch.float32, False,   False,    False),
    (torch.float16, False,   False,    False),
    (torch.float32, False,   True,     False),
    (torch.float16, False,   True,     False),
    (torch.float32, False,   True,     True),
    (torch.float16, False,   True,     True),

    # For FP8 GEMM GeLU is not used.
    (torch.float32, True,    False,    False),
    (torch.float16, True,    False,    False),
    # When enabling bias we must use float16 or bfloat16 (because of kernel limitations)
    (torch.float16, True,    True,     False),
    (torch.bfloat16, True,   True,     False),
])
def test_export_gemm(
    precision, # Precision of inputs, weights, output and bias
    use_fp8,
    use_bias,
    use_gelu,
    scale_factors
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    class TestFP8_GEMM(nn.Module):
        def __init__(self, precision, use_bias, gelu, scale_factors):
            super().__init__()
            self.use_bias = use_bias
            self.gelu = gelu
            self.precision = precision

            self.fp8_tensor_inp = tex.FP8FwdTensors.GEMM1_INPUT
            self.fp8_tensor_weight = tex.FP8FwdTensors.GEMM1_WEIGHT
            nb_inp_scales, nb_weight_scales = 1, out_features
            act_scale_factor, weight_scale_factor = scale_factors
            self.meta_inp = create_meta(act_scale_factor, nb_inp_scales)
            self.meta_weight = create_meta(weight_scale_factor, nb_weight_scales)

            bias_size = nb_weight_scales
            self.bias = torch.randn(bias_size, dtype=precision, device="cuda")
            self.gelu_input = torch.randn(hidden_size, out_features, dtype=precision, device="cuda")

            self.inp_type = tex.DType.kFloat8E4M3
            self.weights_type = tex.DType.kFloat8E4M3
            self.outp_type = precision

        def forward(self, inp, weight):
            inp_fp8 = cast_to_fp8(
                inp,
                self.meta_inp,
                self.fp8_tensor_inp,
                self.inp_type)

            weight_fp8 = cast_to_fp8(
                weight,
                self.meta_weight,
                self.fp8_tensor_weight,
                self.weights_type)

            ret = fp8_gemm(
                weight_fp8,
                self.meta_weight.scale_inv,
                self.fp8_tensor_weight,
                self.inp_type,
                inp_fp8,
                self.meta_inp.scale_inv,
                self.fp8_tensor_inp,
                self.weights_type,
                self.outp_type,
                get_workspace(),
                bias=self.bias,
                use_bias=self.use_bias,
                use_split_accumulator=False)
            return ret

    class Test_GEMM(nn.Module):
        def __init__(self, precision, use_bias=False, gelu=False):
            super().__init__()
            self.use_bias = use_bias
            self.gelu = gelu
            self.precision = precision
            bias_size = out_features
            self.bias = torch.randn(bias_size, dtype=precision, device="cuda")
            self.gelu_input = torch.randn(hidden_size, out_features, dtype=precision, device="cuda")

        def forward(self, inp, weight):
            outp_type = self.precision

            # note: due to logic in lines 104:116 and L129 in cpp_extensions.py
            # it appears either bias OR gelu can be activated, not both
            ret, _, _ = gemm(
                weight,
                inp,
                outp_type,
                get_workspace(),

                # test bias
                bias=self.bias,
                use_bias=self.use_bias,

                # test gelu
                gelu=self.gelu,
                gelu_input=self.gelu_input,
                grad=False # only True for backward pass
            )
            return ret

    # If gelu is applied then bias must be added, as defined by TE kernel.
    if use_gelu: assert use_bias
    # Set dimensions (these are arbitrary).
    out_features = 128
    hidden_size = 256
    in_features = 64
    inp = torch.randn(hidden_size, in_features, dtype=precision, device="cuda")
    weight = torch.randn(out_features, in_features, dtype=precision, device="cuda")
    fp8_str = "_fp8" if use_fp8 else ""
    bias_str = "_bias" if use_bias else ""
    gelu_str = "_gelu" if use_gelu else ""
    high_prec_str = dtype2str(precision)
    fname = f"te.gemm{fp8_str}{bias_str}{gelu_str}{high_prec_str}.onnx"
    if use_fp8:
        model = TestFP8_GEMM(precision, use_bias, use_gelu, scale_factors)
        do_export(model, (inp, weight), fname, use_fp8)
        if precision == torch.bfloat16:
            return
        infer_ort = precision != torch.float16  # temporarily skipping onnxrt inference due to input type mismatch bug
        validate_result(fname, (inp, weight), model, rtol=1e-2, atol=1e-2, is_fp8=True, infer_ort=infer_ort)
    else:
        model = Test_GEMM(precision, use_bias, use_gelu)
        do_export(model, (inp, weight), fname, use_fp8)
        validate_result(fname, (inp, weight), model, rtol=1e-2, atol=2e-2)


@pytest.mark.parametrize("use_fp8", [False, True])
@pytest.mark.parametrize("scale_factor", [448, 112])
@pytest.mark.parametrize("precision", [torch.float32, torch.float16, torch.bfloat16])
@pytest.mark.parametrize("zero_centered_gamma", [False, True])
def test_export_layernorm(
    use_fp8: bool,
    scale_factor: float,
    precision: torch.dtype,
    zero_centered_gamma: bool
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    # Set dimensions (these are arbitrary).
    inp_shape = [64, 32]

    class Test_Layernorm(nn.Module):
        def __init__(self) -> None:
            super().__init__()
            normalized_shape = torch.Size(inp.shape[1:])
            self.weight = torch.randn(*normalized_shape, dtype=precision, device="cuda")
            self.bias = torch.zeros(*normalized_shape, dtype=precision, device="cuda")
            self.eps = 1e-6 # An arbitrary small value

        def forward(self, inp):
            ret = texcpp.layernorm_fwd_inf(
                inp,
                self.weight,
                self.bias,
                self.eps,
                zero_centered_gamma)
            return ret

    class TestFP8_Layernorm(nn.Module):
        def __init__(self) -> None:
            super().__init__()
            normalized_shape = torch.Size(inp.shape[1:])
            self.weight = torch.randn(*normalized_shape, dtype=precision, device="cuda")
            self.bias = torch.zeros(*normalized_shape, dtype=precision, device="cuda")
            self.eps = 1e-6 # An arbitrary small value

            self.fp8_tensor = tex.FP8FwdTensors.GEMM1_INPUT
            self.meta = create_meta(scale_factor)
            self.fp8_type = tex.DType.kFloat8E4M3

        def forward(self, inp):
            ret = texcpp.layernorm_fwd_fp8_inf(
                inp,
                self.weight,
                self.bias,
                self.eps,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                zero_centered_gamma)

            ret = cast_from_fp8(
                ret,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                tex.DType.kFloat32 if precision == torch.float32 else tex.DType.kFloat16)
            return ret

    inp = torch.randn(*inp_shape, device="cuda", dtype=precision)
    model = TestFP8_Layernorm() if use_fp8 else Test_Layernorm()
    high_prec_str = dtype2str(precision)
    fp8_str = f"_fp8-{scale_factor}" if use_fp8 else ""
    fname = f"te.layernorm{fp8_str}{high_prec_str}.onnx"
    do_export(model, inp, fname, use_fp8=use_fp8)
    if precision not in (torch.bfloat16, ):
        validate_result(
            fname, inp, model, atol=1e-4, is_fp8=use_fp8, allow_cnt_errors=3)


@skip_FP8
@pytest.mark.parametrize("softmax_def", [
    softmax_defs.ScaledUpperTriangMaskedSoftmax,
    softmax_defs.ScaledMaskedSoftmax,
    softmax_defs.ScaledSoftmax,
])
# Softmax kernel only supports FP16 or BF16!
@pytest.mark.parametrize("precision", [torch.float16, torch.bfloat16])
def test_export_softmax(softmax_def, precision):
    class Test_Softmax(nn.Module):
        def __init__(self, softmax_function, mask_inp=False):
            super().__init__()
            self.softmax_fn = softmax_function
            self.mask_inp = mask_inp

        def forward(self, inp, mask):
            scale_factor = 8 # arbitrary value
            if self.mask_inp:
                ret = self.softmax_fn.apply(inp, mask, scale_factor)
            else:
                ret = self.softmax_fn.apply(inp, scale_factor)
            return ret

    # Set dimensions (these are arbitrary).
    in_features = 64
    hidden_size = 256
    mask = None
    input_names = ["input"]
    inp_shape = [hidden_size, in_features, in_features, in_features]
    if softmax_def == softmax_defs.ScaledUpperTriangMaskedSoftmax:
        inp_shape = [hidden_size, in_features, in_features]
        kernel_str = "ScaledUpperTriangMaskedSoftmax"
        model = Test_Softmax(softmax_def)
    elif softmax_def == softmax_defs.ScaledMaskedSoftmax:
        # Generate a random mask with 50% probability for 0 or 1.
        probs = 0.5 * torch.ones(hidden_size, 1, in_features, in_features, device="cuda", dtype=precision)
        mask = torch.bernoulli(probs).to("cuda", dtype=torch.bool)
        input_names.append("mask")
        kernel_str = "ScaledMaskedSoftmax"
        model = Test_Softmax(softmax_def, mask_inp=True)
    elif softmax_def == softmax_defs.ScaledSoftmax:
        kernel_str = "ScaledSoftmax"
        model = Test_Softmax(softmax_def)
    input_tensor = torch.randn(*inp_shape, device="cuda")
    input_tensor = input_tensor.to(torch.bfloat16) if precision == torch.bfloat16 else input_tensor.half()
    high_prec_str = dtype2str(precision)
    fname = f"{kernel_str}{high_prec_str}.onnx"
    inp = (input_tensor, mask)
    do_export(model, inp, fname, input_names=input_names)
    if precision != torch.bfloat16:
        validate_result(fname, inp, model, atol=1e-3, input_names=input_names)


@pytest.mark.parametrize("scale_factor", [1])
@pytest.mark.parametrize("use_fp8", [False, True])
# Returning the bias is a TE fusion optimization we don't care about.
@pytest.mark.parametrize("return_bias", [False])
@pytest.mark.parametrize(
    "precision,     use_bias",[
    (torch.float32, False),
    (torch.float32, True),
    (torch.float16, False),
    (torch.float16, True),
    # Todo: cannot configure BF16 when bias is disabled (ORT issue?)
    (torch.bfloat16, False),
    # Todo: cannot configure BF16 when bias is enabled (ORT issue?)
    # (torch.bfloat16, True),
])
def test_export_linear(
    scale_factor: float,
    use_fp8: bool,
    use_bias: bool,
    return_bias: bool,
    precision: torch.dtype
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    # Set dimensions (these are arbitrary).
    in_features = 64
    out_features = 256
    hidden_size = 256

    class Test_Linear(nn.Module):
        def __init__(self,
                in_features,
                out_features,
                use_bias,
                return_bias,
                precision
            ):
            super().__init__()
            self.linear = te.Linear(
                in_features,
                out_features,
                bias=use_bias,
                return_bias=return_bias,
                params_dtype=precision
            )

        def forward(self, inp):
            ret = self.linear(inp)
            return ret

    inp = torch.randn(hidden_size, in_features, device="cuda", dtype=precision)
    fp8_str = "_fp8" if use_fp8 else ""
    bias_str = "_bias" if use_bias else ""
    high_prec_str = dtype2str(precision)
    fname = f"te.linear{fp8_str}{bias_str}{high_prec_str}.onnx"
    with te.fp8_autocast(enabled=use_fp8):
        model = Test_Linear(
            in_features,
            out_features,
            use_bias,
            return_bias,
            precision
        ).to(device='cuda')
        if use_fp8:
            set_layer_scale(model.linear, scale_factor, num_gemms=1)
        do_export(model, inp, fname, use_fp8)

        if precision in (torch.bfloat16, ):
            return
        if not use_fp8:
            validate_result(fname, inp, model, atol=1e-3)
        else:
            validate_result(fname, inp, model, atol=1e-3, is_fp8=use_fp8)


@pytest.mark.parametrize("scale_factor", [112])
@pytest.mark.parametrize("use_fp8", [False, True])
# Returning the bias is a TE fusion optimization we don't care about.
@pytest.mark.parametrize("return_bias", [False])
@pytest.mark.parametrize("return_layernorm_output", [False])
@pytest.mark.parametrize(
    "precision,     use_bias",[
    (torch.float32, False),
    (torch.float32, True),
    (torch.float16, True),
    (torch.float16, False),
])
@pytest.mark.parametrize("zero_centered_gamma", [False, True])
def test_export_layernorm_linear(
    scale_factor: float,
    use_fp8: bool,
    use_bias: bool,
    return_bias: bool,
    return_layernorm_output: bool,
    precision: torch.dtype,
    zero_centered_gamma: bool
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    # Set dimensions (these are arbitrary).
    in_features = 64
    out_features = 256
    hidden_size = 256

    inp = torch.randn(in_features, out_features, device="cuda", dtype=precision)
    fp8_str = "_fp8" if use_fp8 else ""
    bias_str = "_bias" if use_bias else ""
    high_prec_str = dtype2str(precision)
    fname = f"te.layernorm_linear{fp8_str}{bias_str}{high_prec_str}.onnx"

    with te.fp8_autocast(enabled=use_fp8):
        model = te.LayerNormLinear(
            hidden_size,
            3 * hidden_size,
            bias=use_bias,
            return_bias=return_bias,
            return_layernorm_output=return_layernorm_output,
            params_dtype=precision,
            zero_centered_gamma=zero_centered_gamma,
        ).to(device='cuda')
        if use_fp8:
            set_layer_scale(model, scale_factor, num_gemms=1)
        do_export(model, inp, fname, use_fp8)
        if not use_fp8:
            validate_result(fname, inp, model, atol=1e-3)
        elif precision not in (torch.bfloat16,):
            validate_result(fname, inp, model, atol=1e-2, is_fp8=use_fp8)


@pytest.mark.parametrize("scale_factor", [112])
@pytest.mark.parametrize("use_fp8", [False, True])
# Returning the bias is a TE fusion optimization we don't care about.
@pytest.mark.parametrize("return_bias", [False])
@pytest.mark.parametrize("return_layernorm_output", [False])
@pytest.mark.parametrize(
    "precision,     use_bias",[
    (torch.float32, False),
    (torch.float32, True),
    (torch.float16, True),
    (torch.float16, False),
])
@pytest.mark.parametrize("zero_centered_gamma", [False, True])
def test_export_layernorm_mlp(
    scale_factor: float,
    use_fp8: bool,
    use_bias: bool,
    return_bias: bool,
    return_layernorm_output: bool,
    precision: torch.dtype,
    zero_centered_gamma: bool
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    # Set dimensions (these are arbitrary).
    in_features = 64
    out_features = 256
    hidden_size = 256
    ffn_hidden_size = 256

    inp = torch.randn(in_features, out_features, device="cuda", dtype=precision)
    fp8_str = "_fp8" if use_fp8 else ""
    bias_str = "_bias" if use_bias else ""
    high_prec_str = dtype2str(precision)
    fname = f"te.layernorm_mlp{fp8_str}{bias_str}{high_prec_str}.onnx"
    with te.fp8_autocast(enabled=use_fp8):
        model = te.LayerNormMLP(
            hidden_size,
            ffn_hidden_size,
            bias=use_bias,
            return_bias=return_bias,
            return_layernorm_output=return_layernorm_output,
            params_dtype=precision,
            zero_centered_gamma=zero_centered_gamma,
        ).to(device='cuda')
        if use_fp8:
            set_layer_scale(model, scale_factor, num_gemms=2)
        do_export(model, inp, fname, use_fp8)
        if not use_fp8:
            validate_result(fname, inp, model, atol=1e-3)
        else:
            validate_result(fname, inp, model, atol=2e-2, is_fp8=use_fp8)

@skip_FP8
@pytest.mark.parametrize(
    "precision,     use_mask, attn_mask_type", [
    (torch.float32, False,    None),      # calls forward_torch_softmax
    (torch.float32, True,     None),      # calls forward_torch_softmax
    (torch.float16, False,    "causal"),  # calls ScaledUpperTriangMaskedSoftmax
    (torch.float16, True,     "padding"), # calls ScaledMaskedSoftmax
    (torch.float16, False,    "padding"), # calls ScaledSoftmax
])
def test_export_core_attention(
    precision: torch.dtype,
    use_mask: bool,
    attn_mask_type: str,
):
    # Set dimensions (these are arbitrary).
    kv_channels = 64
    num_attention_heads = 1
    qkv_size = (2048, 4, num_attention_heads, kv_channels)

    query_layer = torch.randn(qkv_size, dtype=precision, device="cuda")
    key_layer = torch.randn(qkv_size, dtype=precision, device="cuda")
    value_layer = torch.randn(qkv_size, dtype=precision, device="cuda")
    input_names = ["query", "key", "value"]
    attention_mask = None
    if use_mask:
        # Generate a random mask with 50% probability for 0 or 1.
        probs = 0.5 * torch.ones(qkv_size[1], qkv_size[2], qkv_size[0], qkv_size[0], device="cuda", dtype=precision)
        attention_mask = torch.bernoulli(probs).to("cuda", dtype=torch.bool)
        input_names.append("attention_mask")
    inp = (query_layer, key_layer, value_layer, attention_mask)

    mask_str = get_attn_mask_str(use_mask, attn_mask_type)
    high_prec_str = dtype2str(precision)
    fname = f"te.core_attention{mask_str}{high_prec_str}.onnx"

    if attn_mask_type is None:
        attn_mask_type = 'causal'
        inp = (query_layer, key_layer, value_layer)
    model = te.transformer.DotProductAttention(
        num_attention_heads=num_attention_heads,
        kv_channels=kv_channels,
        attention_dropout=0.5,
        attn_mask_type=attn_mask_type,
    ).to(device='cuda')
    do_export(model,
            inp,
            fname,
            input_names=input_names,
            use_fp8=True)
    validate_result(fname, inp, model, atol=1e-2, input_names=input_names)


test_configs_multihead_attention = [
    #"use_mask, attn_mask_type"
    (False,    "causal"),  # calls ScaledUpperTriangMaskedSoftmax
    (True,     "padding"), # calls ScaledMaskedSoftmax
    (False,    "padding"), # calls ScaledSoftmax
]
test_configs_attention_type = [
    #"input_layernorm, attention_type, fuse_qkv_params"
    (True,             "self",         True),
    (False,            "self",         True),
    (True,             "self",         False),
    (False,            "self",         False),
    # disabled because query_bias (reqd for cross attention) is defined when fuse_qkv_params is False
    # (True,           "cross",        True),
    # (False,          "cross",        True),
    (True,             "cross",        False),
    # disabled because TypeError: cannot assign 'transformer_engine.pytorch.module.Linear'
    # as parameter 'query' (torch.nn.Parameter or None expected)
    # (False,          "cross",        False),
]
@pytest.mark.parametrize("use_fp8", [False, True])
@pytest.mark.parametrize("use_mask, attn_mask_type", test_configs_multihead_attention)
@pytest.mark.parametrize("precision", [torch.float32, torch.float16])
@pytest.mark.parametrize("return_layernorm_output", [False])
@pytest.mark.parametrize("input_layernorm, attention_type, fuse_qkv_params", test_configs_attention_type)
def test_export_multihead_attention(
    use_fp8: bool,
    use_mask: bool,
    attn_mask_type: str,
    precision: torch.dtype,
    return_layernorm_output: bool,
    input_layernorm: bool,
    attention_type: str,
    fuse_qkv_params: bool
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    hidden_size = 256
    sequence_length = 128
    batch_size = 4
    num_attention_heads = 32
    kv_channels = 8
    attention_dropout = 0.1
    layernorm_epsilon = 1e-5
    init_method = output_layer_init_method = get_default_init_method()
    attention_args = (
        hidden_size,
        num_attention_heads,
        kv_channels,
        attention_dropout,
        layernorm_epsilon,
        init_method,
        output_layer_init_method,
    )
    hidden_states = torch.randn(sequence_length, batch_size, hidden_size, dtype=precision, device="cuda")

    attention_mask = None
    if use_mask and attn_mask_type != "causal":
        # Generate a random mask with 50% probability for 0 or 1.
        probs = 0.5 * torch.ones(batch_size, 1, sequence_length, sequence_length, device="cuda", dtype=precision)
        attention_mask = torch.bernoulli(probs).to("cuda", dtype=torch.bool)

    encoder_output = None
    if attention_type == "cross":
        encoder_output = torch.randn(sequence_length, batch_size, hidden_size, dtype=precision, device="cuda")
    inp = (hidden_states, attention_mask, encoder_output)
    input_names = ["hidden_states", "attention_mask", "encoder_output"]
    output_names=["output", "output_1"]

    fp8_str = "_fp8" if use_fp8 else ""
    dtype_str = dtype2str(precision)
    attn_type_str = "_self-attention" if attention_type == "self" else "_cross-attention"
    fuse_qkv_str = "_fused-qkv" if fuse_qkv_params else ""
    attn_mask_str = get_attn_mask_str(use_mask, attn_mask_type)
    input_ln_str = "_input-ln" if input_layernorm else ""
    fname = f"te.multihead_attention{fp8_str}{attn_mask_str}{attn_type_str}{input_ln_str}{fuse_qkv_str}{dtype_str}.onnx"

    model = te.transformer.MultiHeadAttention(
        *attention_args,
        attn_mask_type=attn_mask_type,
        params_dtype=precision,
        return_layernorm_output=return_layernorm_output,
        input_layernorm=input_layernorm,
        attention_type=attention_type,
        fuse_qkv_params=fuse_qkv_params,
    ).to(device='cuda')
    do_export(model, inp, fname, use_fp8, input_names=input_names, output_names=output_names)
    infer_ort = precision != torch.float16  # temporarily skipping onnxrt inference due to input type mismatch bug
    if not use_fp8:
        validate_result(fname, inp, model, atol=1e-3, input_names=input_names, output_names=output_names)
    else:
        validate_result(fname, inp, model, atol=1e-2, is_fp8=use_fp8, input_names=input_names, output_names=output_names, infer_ort=infer_ort)


@pytest.mark.parametrize("use_fp8", [False, True])
@pytest.mark.parametrize("use_mask, attn_mask_type", test_configs_multihead_attention)
@pytest.mark.parametrize("output_layernorm", [
    #True, # TO DO: handle this
    False
])
@pytest.mark.parametrize("precision", [torch.float32, torch.float16])
@pytest.mark.parametrize("fuse_qkv_params", [False, True])
@pytest.mark.parametrize("zero_centered_gamma", [False, True])
def test_export_transformer_layer(
    use_fp8: bool,
    use_mask: bool,
    attn_mask_type: str,
    output_layernorm: bool,
    precision: torch.dtype,
    fuse_qkv_params: bool,
    zero_centered_gamma: bool
):
    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)

    # Layer configuration
    hidden_size = 64
    sequence_length = 128
    batch_size = 1
    ffn_hidden_size = 256
    num_attention_heads = 4

    input_tensor = torch.rand(sequence_length, batch_size, hidden_size, dtype=precision, device="cuda")
    input_names = ["input"]
    attention_mask = None
    if use_mask and attn_mask_type != "causal":
        # Generate a random mask with 50% probability for 0 or 1.
        probs = 0.5 * torch.ones(batch_size, 1, sequence_length, sequence_length, device="cuda", dtype=precision)
        attention_mask = torch.bernoulli(probs).to("cuda", dtype=torch.bool)
        input_names.append("attention_mask")
    inp = (input_tensor, attention_mask)

    fp8_str = "_fp8" if use_fp8 else ""
    fuse_qkv_params_str = "_fused-qkv" if fuse_qkv_params else ""
    high_prec_str = dtype2str(precision)
    attn_mask_str = get_attn_mask_str(use_mask, attn_mask_type)
    fname = f"te.transformer_layer{fp8_str}{attn_mask_str}{fuse_qkv_params_str}{high_prec_str}.onnx"

    model = te.TransformerLayer(
        hidden_size,
        ffn_hidden_size,
        num_attention_heads,
        self_attn_mask_type=attn_mask_type,
        output_layernorm=output_layernorm,
        params_dtype=precision,
        fuse_qkv_params=fuse_qkv_params,
        zero_centered_gamma=zero_centered_gamma).to(device='cuda')
    do_export(model, inp, fname, use_fp8)
    infer_ort = precision != torch.float16  # temporarily skipping onnxrt inference due to input type mismatch bug
    if not use_fp8:
        validate_result(fname, inp, model, atol=1e-3, input_names=input_names)
    else:
        validate_result(fname, inp, model, atol=5e-1, is_fp8=use_fp8, input_names=input_names, infer_ort=infer_ort)


@pytest.mark.parametrize("use_fp8", [True])
@pytest.mark.parametrize("ln_scale_factor", [448*2])
@pytest.mark.parametrize("gemm_scale_factors", [(224, 224,),])
@pytest.mark.parametrize("precision", [torch.float32, torch.float16, torch.bfloat16])
@pytest.mark.parametrize("zero_centered_gamma", [False, True])
def test_export_gemm_layernorm(
    use_fp8: bool,
    ln_scale_factor: float,
    gemm_scale_factors: Tuple[float, float],
    precision: torch.dtype,
    zero_centered_gamma: bool
):
    """This is a regression test for testing that all LN inputs have the same type.

    The test sets up GEMM with FP32 output which feeds into an LN that is configured
    with FP16 or BF16 weights and bias.
    """

    # Skip FP8 tests on non-hopper devices
    if use_fp8 and not fp8_available:
        pytest.skip(reason_for_no_fp8)
    class TestFP8_GemmLayernorm(nn.Module):
        def __init__(self) -> None:
            super().__init__()
            normalized_shape = torch.Size(inp.shape[1:])
            self.weight = torch.randn(*normalized_shape, dtype=precision, device="cuda")
            self.bias = torch.zeros(*normalized_shape, dtype=precision, device="cuda")
            self.eps = 1e-6 # An arbitrary small value

            self.fp8_tensor = tex.FP8FwdTensors.GEMM1_INPUT
            self.meta = create_meta(ln_scale_factor)
            self.fp8_type = tex.DType.kFloat8E4M3
            self.gemm = TestFP8_GEMM(
                precision, use_bias=False, gelu=False, scale_factors=gemm_scale_factors)

        def forward(self, inp, weight):
            x = self.gemm(inp, weight)
            x = texcpp.layernorm_fwd_fp8_inf(
                x,
                self.weight,
                self.bias,
                self.eps,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                zero_centered_gamma)

            x = cast_from_fp8(
                x,
                self.meta,
                self.fp8_tensor,
                self.fp8_type,
                tex.DType.kFloat32 if precision == torch.float32 else tex.DType.kFloat16)
            return x

    out_features = 128
    hidden_size = 128
    in_features = 128
    class TestFP8_GEMM(nn.Module):
        def __init__(self, precision, use_bias, gelu, scale_factors):
            super().__init__()
            self.use_bias = use_bias
            self.gelu = gelu
            self.precision = precision

            self.fp8_tensor_inp = tex.FP8FwdTensors.GEMM1_INPUT
            self.fp8_tensor_weight = tex.FP8FwdTensors.GEMM1_WEIGHT
            nb_inp_scales, nb_weight_scales = 1, out_features
            act_scale_factor, weight_scale_factor = scale_factors
            self.meta_inp = create_meta(act_scale_factor, nb_inp_scales)
            self.meta_weight = create_meta(weight_scale_factor, nb_weight_scales)

            bias_size = nb_weight_scales
            self.bias = torch.randn(bias_size, dtype=precision, device="cuda")
            self.gelu_input = torch.randn(hidden_size, out_features, dtype=precision, device="cuda")

            self.inp_type = tex.DType.kFloat8E4M3
            self.weights_type = tex.DType.kFloat8E4M3
            self.outp_type = precision

        def forward(self, inp, weight):
            inp_fp8 = cast_to_fp8(
                inp,
                self.meta_inp,
                self.fp8_tensor_inp,
                self.inp_type)

            weight_fp8 = cast_to_fp8(
                weight,
                self.meta_weight,
                self.fp8_tensor_weight,
                self.weights_type)

            ret = fp8_gemm(
                weight_fp8,
                self.meta_weight.scale_inv,
                self.fp8_tensor_weight,
                self.inp_type,
                inp_fp8,
                self.meta_inp.scale_inv,
                self.fp8_tensor_inp,
                self.weights_type,
                self.outp_type,
                get_workspace(),
                bias=self.bias,
                use_bias=self.use_bias,
                use_split_accumulator=False)
            return ret

    inp = torch.randn(hidden_size, in_features, dtype=precision, device="cuda")
    weight = torch.randn(out_features, in_features, dtype=precision, device="cuda")
    model = TestFP8_GemmLayernorm()
    high_prec_str = dtype2str(precision)
    fp8_str = f"_fp8" if use_fp8 else ""
    fname = f"te.gemm_layernorm{fp8_str}{high_prec_str}.onnx"
    do_export(model, (inp, weight), fname, use_fp8=use_fp8)
    if precision not in (torch.bfloat16, ):
        validate_result(
            fname, (inp, weight), model, atol=5e-2, is_fp8=use_fp8, allow_cnt_errors=2)


@pytest.mark.parametrize("enabled", [True, False])
def test_export_ctx_manager(enabled):
    assert is_in_onnx_export_mode() == False
    with te.onnx_export(enabled):
        assert is_in_onnx_export_mode() == enabled
    assert is_in_onnx_export_mode() == False