Add: Sparse24_compressor + tests

src/compressed_tensors/compressors/sparse_compressors/__init__.py

@@ -15,4 +15,5 @@
 
 from .base import *
 from .dense import *
+from .sparse_24 import *
 from .sparse_bitmask import *

src/compressed_tensors/compressors/sparse_compressors/sparse_24.py

@@ -0,0 +1,92 @@
+# Copyright (c) 2021 - present / Neuralmagic, Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+from typing import Dict
+
+from compressed_tensors.compressors.base import BaseCompressor
+from compressed_tensors.compressors.sparse_compressors.base import BaseSparseCompressor
+from compressed_tensors.config import CompressionFormat, SparsityStructure
+from compressed_tensors.utils import (
+    merge_names,
+    sparse_semi_structured_from_dense_cutlass,
+    sparse_semi_structured_to_dense_cutlass,
+    tensor_follows_mask_structure,
+)
+from torch import Tensor
+
+
+@BaseCompressor.register(name=CompressionFormat.sparse_24.value)
+class Sparse24Compressor(BaseSparseCompressor):
+    """
+    Compresses a with 2:4 sparsity structure for inference
+    with sparse 2:4 kernels for float/float16/bfloat16.
+    https://github.com/pytorch/pytorch/blob/78cf8df4a019e919e8eac5f5d048d8842d4fc692/torch/sparse/semi_structured.py
+    """
+
+    COMPRESSION_PARAM_NAMES = ["sparse_24_packed_weight", "meta"]
+
+    @staticmethod
+    def validate_sparsity_structure(name: str, weight: Tensor) -> bool:
+        """
+        Checks if a tensor fits the required 2:4 sparsity structure
+        :param name: name of the tensor to check
+        :param weight: tensor to check for sparsity structure
+        :return: True if all rows match the 2:4 sparsity structure, raises
+            ValueError otherwise
+        """
+
+        if not tensor_follows_mask_structure(
+            weight, mask=SparsityStructure.TWO_FOUR.value
+        ):
+            raise ValueError(
+                "Sparse24Compressor is only compatible with weights that have "
+                f"a 2:4 sparsity structure. Found segments in {name} "
+                "that do not match the expected structure."
+            )
+
+        return True
+
+    def compress_weight(self, name: str, value: Tensor) -> Dict[str, Tensor]:
+        """
+        Compresses a given with 2:4 sparsity structure.
+        :param name: name of the tensor in state dict of uncompressed model
+        :param value: 2:4 sparse tensor to compress
+        :return: dictionary containing the compressed weight and associated
+            metadata
+        """
+        weight_suffix = ".weight"
+        if not name.endswith(weight_suffix):
+            return {}
+
+        prefix = name[: -len(weight_suffix)]
+        self.validate_sparsity_structure(name=prefix, weight=value)
+        sparse_24_packed_weight, meta = sparse_semi_structured_from_dense_cutlass(
+            dense=value
+        )
+        return {
+            merge_names(name, "sparse_24_packed_weight"): sparse_24_packed_weight.cpu(),
+            merge_names(name, "meta"): meta.cpu(),
+        }
+
+    def decompress_weight(self, weight_data):
+        assert (
+            "sparse_24_packed_weight" in weight_data
+        ), "sparse_24_packed_weight not found in weight_data"
+        assert "meta" in weight_data, "meta not found in weight_data"
+
+        return sparse_semi_structured_to_dense_cutlass(
+            sparse=weight_data["sparse_24_packed_weight"],
+            meta_reordered=weight_data["meta"],
+        )

src/compressed_tensors/config/__init__.py

@@ -15,4 +15,5 @@
 # flake8: noqa
 from .base import *
 from .dense import *
+from .sparse_24 import *
 from .sparse_bitmask import *

src/compressed_tensors/config/base.py

@@ -26,6 +26,7 @@
 class CompressionFormat(Enum):
     dense = "dense"
     sparse_bitmask = "sparse-bitmask"
+    sparse_24 = "sparse-24"
     int_quantized = "int-quantized"
     float_quantized = "float-quantized"
     naive_quantized = "naive-quantized"

src/compressed_tensors/config/sparse_24.py

@@ -0,0 +1,37 @@
+# Copyright (c) 2021 - present / Neuralmagic, Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from typing import Optional
+
+from compressed_tensors.config import (
+    CompressionFormat,
+    SparsityCompressionConfig,
+    SparsityStructure,
+)
+
+
+__all__ = ["Sparse24Config"]
+
+
+@SparsityCompressionConfig.register(name=CompressionFormat.sparse_24.value)
+class Sparse24Config(SparsityCompressionConfig):
+    """
+    Configuration for storing a sparse model using 2:4 compression
+    :param global_sparsity: average sparsity of the entire model
+    :param sparsity_structure: structure of the sparsity, "2:4"
+    """
+
+    format: str = CompressionFormat.sparse_24.value
+    global_sparsity: Optional[float] = 0.0
+    sparsity_structure: Optional[str] = SparsityStructure.TWO_FOUR.value

src/compressed_tensors/utils/semi_structured_conversions.py

@@ -75,6 +75,7 @@ def _calculate_meta_reordering_scatter_offsets(m, meta_ncols, meta_dtype, device
 # This function converts dense matrix into sparse semi-structured
 # representation, producing "compressed" matrix, in the layout used by
 # CUTLASS backend, and corresponding metadata matrix.
+# Modified from https://github.com/pytorch/pytorch/blob/78cf8df4a019e919e8eac5f5d048d8842d4fc692/torch/sparse/_semi_structured_conversions.py#L47
 def sparse_semi_structured_from_dense_cutlass(dense):
     if dense.dim() != 2:
         raise RuntimeError(
@@ -85,7 +86,7 @@ def sparse_semi_structured_from_dense_cutlass(dense):
     device = dense.device
 
     meta_dtype = torch.int8
-    if dense.dtype == torch.int8:
+    if dense.dtype == torch.int8 or dense.dtype == torch.float8_e4m3fn:
         meta_dtype = torch.int32
     elif dense.dtype in [torch.half, torch.bfloat16, torch.float, torch.int32]:
         meta_dtype = torch.int16
@@ -165,11 +166,15 @@ def sparse_semi_structured_from_dense_cutlass(dense):
     idxs1 = bit2 | (bit3.to(torch.int64) << 1)
 
     if dense.dtype != torch.float:
+        if dense.dtype == torch.float8_e4m3fn:
+            dense_4 = dense_4.view(torch.int8)
         sparse0 = dense_4.gather(
             -1, idxs0.unsqueeze(-1)
         )  # type: ignore[possibly-undefined]
         sparse1 = dense_4.gather(-1, idxs1.unsqueeze(-1))
         sparse = torch.stack((sparse0, sparse1), dim=-1).view(m, k // 2)
+        if dense.dtype == torch.float8_e4m3fn:
+            sparse = sparse.view(torch.float8_e4m3fn)
     else:
         sparse = dense_2.gather(-1, idxs0.unsqueeze(-1) // 2).view(
             m, k // 2
@@ -213,6 +218,7 @@ def sparse_semi_structured_from_dense_cutlass(dense):
 # reconstructs dense matrix from a pair of "compressed" matrix, given
 # in the layout used by CUTLASS backend, and accompanying metadata
 # matrix.
+# Copied from https://github.com/pytorch/pytorch/blob/78cf8df4a019e919e8eac5f5d048d8842d4fc692/torch/sparse/_semi_structured_conversions.py#L180
 def sparse_semi_structured_to_dense_cutlass(sparse, meta_reordered):
     if sparse.dim() != 2:
         raise RuntimeError(
@@ -298,16 +304,21 @@ def sparse_semi_structured_to_dense_cutlass(sparse, meta_reordered):
         torch.arange(0, 2 * m * k // ksparse, device=device) * 4
     ).view(-1, 1).repeat(1, 2).view(-1)
 
-    dense = torch.zeros((m * 2 * k,), dtype=sparse.dtype, device=device)
+    sparse_dtype = sparse.dtype if sparse.dtype != torch.float8_e4m3fn else torch.int8
+    dense = torch.zeros((m * 2 * k,), dtype=sparse_dtype, device=device)
     if sparse.dtype != torch.float:
         # dense.scatter_(0, dense_offsets, sparse.view(-1))
-        dense.scatter_(0, dense_offsets, sparse.reshape(-1))
+        if sparse.dtype == torch.float8_e4m3fn:
+            dense.scatter_(0, dense_offsets, sparse.view(torch.int8).view(-1))
+        else:
+            dense.scatter_(0, dense_offsets, sparse.reshape(-1))
     else:
         dense.view(torch.half).scatter_(
             0, dense_offsets, sparse.view(torch.half).view(-1)
         )
 
-    return dense.view(m, 2 * k)
+    result = dense.view(m, 2 * k)
+    return result.view(sparse.dtype)
 
 
 def mask_creator(tensor):

tests/test_utils/test_semi_structured_conversions.py

@@ -0,0 +1,66 @@
+# Copyright (c) 2021 - present / Neuralmagic, Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import pytest
+import torch
+from compressed_tensors.utils.semi_structured_conversions import (
+    sparse_semi_structured_from_dense_cutlass,
+    sparse_semi_structured_to_dense_cutlass,
+)
+
+
+def supported_dtypes():
+    return [torch.int8, torch.float16, torch.bfloat16, torch.float8_e4m3fn]
+
+
+def get_random_mat(M, K, dtype):
+    rand_tensor_dtype = dtype
+    if dtype in [torch.int8, torch.float8_e4m3fn]:
+        rand_tensor_dtype = torch.float16
+    mat = torch.rand(M, K, dtype=rand_tensor_dtype).cuda()
+    mat = mat.masked_fill_(mat == 0, 1)
+    return mat.to(dtype)
+
+
+def generate_pruned_semi_structured_mat(M, K, dtype):
+    mask = torch.Tensor([0, 0, 1, 1]).tile((M, K // 4)).bool()
+    rand_tensor_dtype = dtype
+    if dtype in [torch.int8, torch.float8_e4m3fn]:
+        rand_tensor_dtype = torch.float16
+    mat = torch.rand(M, K, dtype=rand_tensor_dtype)
+    mat = mat.masked_fill_(mat == 0, 1)
+    if dtype == torch.float8_e4m3fn:
+        # some float8_e4m3fn operations are not supported on CPU
+        mat = mat.cuda()
+        mask = mask.cuda()
+    mat = mat * mask
+    return mat.to(dtype)
+
+
+@pytest.mark.parametrize("dtype", supported_dtypes())
+def test_inverse_property_from_dense_then_to_dense(dtype):
+    M, K = 1024, 1024
+    dense_matrix = generate_pruned_semi_structured_mat(M, K, dtype)
+    compressed_matrix, meta = sparse_semi_structured_from_dense_cutlass(dense_matrix)
+    result = sparse_semi_structured_to_dense_cutlass(compressed_matrix, meta)
+
+    assert (
+        dense_matrix.dtype == result.dtype
+    ), f"Dtype Mis-match: {dense_matrix.dtype} and {result.dtype}"
+    assert (
+        dense_matrix.shape == result.shape
+    ), f"Shape Mis-match: {dense_matrix.shape} and {result.shape}"
+    assert torch.equal(
+        dense_matrix, result
+    ), f"Failed for dtype: {dense_matrix.dtype} and input: {dense_matrix}"