Files
wehub-resource-sync 26446540fa
Lint / lint (push) Has been cancelled
CI / MacOS (push) Has been cancelled
CI / Windows (push) Has been cancelled
chore: import upstream snapshot with attribution
2026-07-13 13:36:25 +08:00

690 lines
25 KiB
Python

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you 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.
# ruff: noqa: E741, F821
"""A rule for GEMV and DecodeGEMV."""
from functools import reduce
from tvm import s_tir, tirx
from tvm.target import Target
from ..analysis import (
SBlockInfo,
get_max_shared_memory_per_block,
is_broadcast_epilogue,
is_gemv,
normalize,
normalize_prim_func,
)
from ..base import auto_vectorize, get_bytes, get_extent, try_inline_contiguous_spatial
from .base import GPUScheduleRule
class GEMV(GPUScheduleRule):
"""A rule for GEMV and DecodeGEMV."""
def apply( # pylint: disable=too-many-locals,too-many-branches,too-many-return-statements
self,
func: tirx.PrimFunc,
target: Target,
_: bool,
) -> None | s_tir.Schedule | list[s_tir.Schedule]:
if not isinstance(func, tirx.PrimFunc) or not self.is_target_available(target):
return None
sch = s_tir.Schedule(func)
block_infos = normalize_prim_func(sch)
block_infos = try_inline_contiguous_spatial(sch, block_infos)
if block_infos is None:
return None
if len(block_infos) == 1:
epilogue = None
elif len(block_infos) == 2:
epilogue = block_infos[1]
if not epilogue.is_injective():
return None
else:
return None
block_info = block_infos[0]
if len(block_info.iters) not in [2, 3]:
# either [B, S, R] = [B, S, R] * [B, R]
# or [S, R] = [S, R] * [R]
return None
block = block_info.block_rv
vector_input_buffers = is_gemv(sch, block_info)
if vector_input_buffers is None:
return None
# Step 1. Normalize the block, merge spatial and reduction iters
is_inner_reduction = normalize(sch, block_info)
# Step 2. Do the scheduling
if is_inner_reduction is None:
return None
elif is_inner_reduction:
return self.sch_inner_reduction(sch, target, block, vector_input_buffers, epilogue)
else:
ret = self.sch_outer_reduction(sch, target, block, vector_input_buffers, epilogue)
if ret is None:
return self.sch_outer_reduction_fallback(
sch, target, block, vector_input_buffers, epilogue
)
return sch
def sch_inner_reduction( # pylint: disable=too-many-arguments, invalid-name, unused-argument
self,
sch: s_tir.Schedule,
target: Target,
block: s_tir.schedule.SBlockRV,
vector_input_buffers: list[tirx.Buffer],
epilogue_info: SBlockInfo | None,
):
"""Schedule the inner reduction block."""
def get_max_factor(n, factors):
factors = sorted(factors, reverse=True)
for factor in factors:
if n % factor == 0:
return factor
return 1
def apply(
sch: s_tir.Schedule,
gemv,
TAG_S,
TAG_R,
TS,
TR,
TILE_S,
TILE_R,
VEC_LOAD,
VEC_C,
LOAD_V_SHARED,
LOAD_V_VEC,
UNROLL,
SUPPORT_WARP_SHUFFLE,
):
# rfactor: reduce to tx * vec_c
_, s, r, c = sch.get_loops(block=gemv)
s = sch.fuse(_, s)
r = sch.fuse(r, c)
bx, ts, tile_s = sch.split(s, factors=[None, TS, TILE_S], preserve_unit_iters=True)
r, tr, tile_r_vec_n, vec_c = sch.split(
r, factors=[None, TR, TILE_R // VEC_C, VEC_C], preserve_unit_iters=True
)
sch.reorder(r, tile_r_vec_n, tr, vec_c)
tr_vec_c = sch.fuse(tr, vec_c)
rf = sch.rfactor(tr_vec_c, 0)
# rfactor: reduce to tx
bx, ts, tile_s, tr_vec_c = sch.get_loops(block=gemv)
tr, vec_c = sch.split(tr_vec_c, factors=[TR, None], preserve_unit_iters=True)
rf2 = sch.rfactor(tr, 0)
# bind, vectorize compute
bx, ts, tile_s, r, tile_r_vec_n, tr_vec_c = sch.get_loops(block=rf)
tr, vec_c = sch.split(tr_vec_c, factors=[TR, None], preserve_unit_iters=True)
sch.reorder(bx, ts, tr, r, tile_s, tile_r_vec_n, vec_c)
sch.bind(bx, "blockIdx.x")
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
sch.vectorize(vec_c)
shared_mem_usage = 0
for buf in vector_input_buffers:
dtype_bytes = get_bytes(buf.dtype)
buf_size = (
reduce(lambda x, y: x * y, buf.shape, tirx.IntImm(buf.shape[0].ty, 1))
* dtype_bytes
)
shared_mem_usage += buf_size
if not SUPPORT_WARP_SHUFFLE:
# When warp shuffle is not able, cross-thread allreduce
# is implemented with shared memory.
shared_mem_usage += TS * TR * dtype_bytes
max_smem = get_max_shared_memory_per_block(target)
LOAD_V_SHARED = (
LOAD_V_SHARED
and isinstance(shared_mem_usage, tirx.IntImm)
and shared_mem_usage.value <= max_smem
)
# vectorize load A
# (TODO) this is now actually problematic since the number of loops is dependent on the
# number of dimensions of A_q
Aq_local = sch.cache_read(rf, read_buffer_index=1, storage_scope="local")
sch.compute_at(Aq_local, r, preserve_unit_loops=True)
s_local, r_local = sch.get_loops(block=Aq_local)[-2:]
fused_load = sch.fuse(s_local, r_local)
aq_vec_len = max(1, VEC_LOAD // get_bytes(sch.get(Aq_local).reads[0].buffer.dtype))
fused_load, vec_load = sch.split(
fused_load, factors=[None, aq_vec_len], preserve_unit_iters=True
)
sch.vectorize(vec_load)
# load vector into shared memory, shape should be the whole vector
if LOAD_V_SHARED:
if len(vector_input_buffers) != 1:
return None
V_shared = sch.cache_read(rf, read_buffer_index=0, storage_scope="shared")
sch.compute_at(V_shared, tr, preserve_unit_loops=True)
l = sch.get_loops(block=V_shared)[-1]
loop: tirx.For = sch.get(l)
if isinstance(loop.extent, tirx.IntImm):
# avoid introducing predicates when vector length is too large
vec_length = max(
min(
get_max_factor(
(int)(loop.extent),
[TS * TR * 1, TS * TR * 2, TS * TR * 4, TS * TR * 8],
)
// TS
// TR,
LOAD_V_VEC,
),
1,
)
else:
vec_length = LOAD_V_VEC
if TAG_R == "threadIdx.x":
_, ty, tx, vec = sch.split(
l, factors=[None, TS, TR, vec_length], preserve_unit_iters=True
)
else:
_, ty, tx, vec = sch.split(
l, factors=[None, TR, TS, vec_length], preserve_unit_iters=True
)
sch.bind(ty, "threadIdx.y")
sch.bind(tx, "threadIdx.x")
sch.vectorize(vec)
# reduce tile_s * tr * vec to tile_s * tr
sch.reverse_compute_at(rf2, loop=bx, preserve_unit_loops=True)
tr, vec_c, *ts_tile_s = sch.get_loops(block=rf2)[1:]
ts_tile_s = sch.fuse(*ts_tile_s)
ts_o, ts_i, tile_s = sch.split(
ts_tile_s, factors=[None, TS, TILE_S], preserve_unit_iters=True
)
tile_s, vec_s = sch.split(
tile_s,
factors=[None, get_max_factor(TILE_S, [1, 2, 4, 8])],
preserve_unit_iters=True,
)
assert sch.get(ts_o).extent.value == 1
ts = sch.fuse(ts_o, ts_i)
sch.reorder(ts, tr, tile_s, vec_s, vec_c)
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
sch.vectorize(vec_s)
# reduce tile_s * tr to tile_s
sch.reverse_compute_at(gemv, loop=bx, preserve_unit_loops=True)
tr, *ts_tile_s = sch.get_loops(block=gemv)[1:]
ts_tile_s = sch.fuse(*ts_tile_s)
ts_o, ts_i, tile_s = sch.split(
ts_tile_s, factors=[None, TS, TILE_S], preserve_unit_iters=True
)
assert sch.get(ts_o).extent.value == 1
ts = sch.fuse(ts_o, ts_i)
sch.reorder(tile_s, ts, tr)
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
sch.decompose_reduction(rf, loop=sch.get_loops(block=rf)[3])
sch.decompose_reduction(rf2, loop=sch.get_loops(block=rf2)[-1])
sch.set_scope(rf, buffer_index=0, storage_scope="local")
sch.set_scope(rf2, buffer_index=0, storage_scope="local")
unroll_factor = UNROLL
sch.annotate(
block_or_loop=sch.get_loops(rf)[3],
ann_key="pragma_auto_unroll_max_step",
ann_val=unroll_factor,
)
sch.annotate(
block_or_loop=sch.get_loops(rf)[3], ann_key="pragma_unroll_explicit", ann_val=1
)
sch.annotate(
block_or_loop=sch.get_loops(rf2)[3],
ann_key="pragma_auto_unroll_max_step",
ann_val=unroll_factor,
)
sch.annotate(
block_or_loop=sch.get_loops(rf2)[3], ann_key="pragma_unroll_explicit", ann_val=1
)
if LOAD_V_SHARED:
sch.annotate(
block_or_loop=sch.get_loops(V_shared)[-4],
ann_key="pragma_unroll_explicit",
ann_val=unroll_factor,
)
sch.annotate(
block_or_loop=sch.get_loops(V_shared)[-4], ann_key="pragma_vectorize", ann_val=1
)
# Schedule epilogue
if epilogue_info is not None:
epilogue = epilogue_info.block_rv
if is_broadcast_epilogue(sch, block, epilogue):
sch.reverse_compute_at(epilogue, bx)
sch.set_scope(block, 0, "shared")
_, _, *s = sch.get_loops(epilogue) # pylint: disable=invalid-name
_, tx = sch.split(sch.fuse(*s), factors=[None, TX])
sch.bind(tx, "threadIdx.x")
else:
sch.reverse_compute_at(epilogue, bx, preserve_unit_loops=True)
ts_tile_s = sch.fuse(*sch.get_loops(epilogue)[1:])
ts_tile_s = sch.get_loops(epilogue)[-1]
ts_o, ts_i, tile_s = sch.split(
ts_tile_s, factors=[None, TS, TILE_S], preserve_unit_iters=True
)
assert sch.get(ts_o).extent.value == 1
ts = sch.fuse(ts_o, ts_i)
sch.bind(ts, TAG_S)
sch.set_scope(block, 0, "local")
# pylint: enable=invalid-name
return sch
# Specify the `len_tx` and `len_ty` according to the loop extent
batch, s, r, c = sch.get_loops(block=block)
len_batch, len_s, len_r, len_c = (
get_extent(sch, batch),
get_extent(sch, s),
get_extent(sch, r),
get_extent(sch, c),
)
len_S = len_batch * len_s
len_R = len_r * len_c
TAG_S, TAG_R = "threadIdx.y", "threadIdx.x"
SUPPORT_WARP_SHUFFLE = False
VEC_LOAD = 1
if target.kind.name == "cuda":
VEC_C = 4
LOAD_V_SHARED = True
LOAD_V_VEC = 8
VEC_LOAD = 4
UNROLL = 256
SUPPORT_WARP_SHUFFLE = True
if isinstance(len_S, int):
TS, TR = 16, 32
else:
TS, TR = 1, 64
elif target.kind.name == "metal":
# Note that the following tile size is tuned on M2 Ultra for 7B
TAG_S, TAG_R = "threadIdx.x", "threadIdx.y"
VEC_C = 1
LOAD_V_SHARED = False
LOAD_V_VEC = -1
UNROLL = 256
SUPPORT_WARP_SHUFFLE = True
if isinstance(len_S, int):
if len_S > len_R:
TS, TR = 4, 16
else:
TS, TR = 2, 64
else:
TS, TR = 1, 64
elif target.kind.name == "rocm":
VEC_C = 4
# TODO: set LOAD_V_SHARED = False for now
# rocm might have some issues when load/store of shared do not belong to same data type
# and only works for certain vector lens, our commonly useful vector lens are in 4
LOAD_V_SHARED = False
LOAD_V_VEC = 8
UNROLL = 256
if isinstance(len_S, int):
if len_S > len_R:
TS, TR = 1, 128
else:
TS, TR = 8, 64
else:
TS, TR = 1, 64
elif target.kind.name == "opencl" and (
("android" in str(target.host)) or ("adreno" in str(target.attrs))
):
TAG_S, TAG_R = "threadIdx.x", "threadIdx.y"
VEC_C = 8
LOAD_V_SHARED = False
LOAD_V_VEC = -1
UNROLL = 8
TS, TR = 2, 32
elif target.kind.name == "vulkan":
VEC_C = 4
LOAD_V_SHARED = True
LOAD_V_VEC = 4
UNROLL = 256
if isinstance(len_S, int):
if len_S > len_R:
TS, TR = 4, 32
else:
TS, TR = 16, 32
else:
TS, TR = 1, 64
elif target.kind.name == "opencl" and "mali" in str(target.attrs):
VEC_C = 8
LOAD_V_SHARED = False
LOAD_V_VEC = -1
UNROLL = 64
TS, TR = 1, 64
else:
VEC_C = 1
LOAD_V_SHARED = False
LOAD_V_VEC = -1
UNROLL = 64
TS, TR = 1, 64
while TS * TR > int(target.attrs["max_num_threads"]):
if TS > 1:
TS //= 2
else:
TR //= 2
TILE_S, TILE_R = (
1,
(
len_c
if len_c > 1
else max(get_max_factor(len_r, [TR * 1, TR * 2, TR * 4, TR * 8]) // TR, 1)
),
)
VEC_C = min(get_max_factor(TILE_R, [1, 2, 4, 8]), VEC_C)
return apply(
sch,
gemv=block,
TAG_S=TAG_S,
TAG_R=TAG_R,
TS=TS,
TR=TR,
TILE_S=TILE_S,
TILE_R=TILE_R,
VEC_LOAD=VEC_LOAD,
VEC_C=VEC_C,
LOAD_V_SHARED=LOAD_V_SHARED,
LOAD_V_VEC=LOAD_V_VEC,
UNROLL=UNROLL,
SUPPORT_WARP_SHUFFLE=SUPPORT_WARP_SHUFFLE,
)
def sch_outer_reduction( # pylint: disable=too-many-arguments, invalid-name, unused-argument
self,
sch: s_tir.Schedule,
target: Target,
block: s_tir.schedule.SBlockRV,
vector_input_buffers: list[tirx.Buffer],
epilogue_info: SBlockInfo | None,
):
"""Schedule the outer reduction block."""
def get_max_factor(n, factors):
factors = sorted(factors, reverse=True)
for factor in factors:
if n % factor == 0:
return factor
return 1
def apply(
sch: s_tir.Schedule,
gemv,
TAG_S,
TAG_R,
TS,
TR,
SCALE_PACK,
DEC_PACK,
VEC_LOAD,
VEC_C,
LOAD_V_SHARED,
LOAD_V_VEC,
UNROLL,
LOAD_V_TILE,
):
# rfactor: reduce to tx * vec_c
batch, s, r, c = sch.get_loops(block=gemv)
s = sch.fuse(batch, s)
r = sch.fuse(r, c)
bx, ts = sch.split(s, factors=[None, TS], preserve_unit_iters=True)
r, v_tile, tr, tile_r, vec_c = sch.split(
r, factors=[None, LOAD_V_TILE, TR, SCALE_PACK, DEC_PACK], preserve_unit_iters=True
)
sch.reorder(bx, ts, r, v_tile, tile_r, tr, vec_c)
tr_vec_c = sch.fuse(tr, vec_c)
rf = sch.rfactor(tr_vec_c, 0)
# rfactor: reduce to tx
bx, ts, tr_vec_c = sch.get_loops(block=gemv)
tr, vec_c = sch.split(tr_vec_c, factors=[TR, None], preserve_unit_iters=True)
rf2 = sch.rfactor(tr, 0)
# bind, vectorize compute
bx, ts, r, v_tile, tile_r, tr_vec_c = sch.get_loops(block=rf)
tr, vec_c = sch.split(tr_vec_c, factors=[TR, DEC_PACK])
sch.reorder(bx, ts, tr, r, v_tile, tile_r, vec_c)
# sch.bind(batch, "blockIdx.z")
sch.bind(bx, "blockIdx.x")
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
auto_vectorize(sch, vec_c, VEC_C)
# decompose independent scale read to outer loop
block_rf_stmt = sch.get(rf)
if len(block_rf_stmt.reads) >= 3:
As_local = sch.cache_read(rf, read_buffer_index=2, storage_scope="local")
sch.compute_at(As_local, v_tile, preserve_unit_loops=True)
# *tile_thr, vec_s = sch.get_loops(block=As_local)
# sch.vectorize(vec_s)
Aq_local = sch.cache_read(rf, read_buffer_index=1, storage_scope="local")
sch.compute_at(Aq_local, tile_r, preserve_unit_loops=True)
# *tile_thr, vec_s = sch.get_loops(block=Aq_local)
# sch.vectorize(vec_s)
if LOAD_V_SHARED:
V_shared = sch.cache_read(rf, read_buffer_index=0, storage_scope="shared")
sch.compute_at(V_shared, r, preserve_unit_loops=True)
l = sch.get_loops(block=V_shared)[-1]
_, v_tile, ts, tr, vec = sch.split(
l, factors=[None, LOAD_V_TILE, TS, TR, LOAD_V_VEC], preserve_unit_iters=True
)
sch.bind(tr, TAG_R)
sch.bind(ts, TAG_S)
auto_vectorize(sch, vec, LOAD_V_VEC)
# reduce tile_s * tr * vec to tile_s * tr
sch.reverse_compute_at(rf2, loop=bx, preserve_unit_loops=True)
tr, vec_c, ts = sch.get_loops(block=rf2)[1:]
sch.reorder(ts, tr, vec_c)
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
# reduce tile_s * tr to tile_s
sch.reverse_compute_at(gemv, loop=bx, preserve_unit_loops=True)
tr, ts = sch.get_loops(block=gemv)[1:]
sch.reorder(ts, tr)
sch.bind(ts, TAG_S)
sch.bind(tr, TAG_R)
sch.decompose_reduction(rf, loop=sch.get_loops(block=rf)[2])
sch.decompose_reduction(rf2, loop=sch.get_loops(block=rf2)[-1])
sch.set_scope(rf, buffer_index=0, storage_scope="local")
sch.set_scope(rf2, buffer_index=0, storage_scope="local")
sch.annotate(
block_or_loop=sch.get_loops(rf2)[3],
ann_key="pragma_auto_unroll_max_step",
ann_val=UNROLL,
)
sch.annotate(
block_or_loop=sch.get_loops(rf2)[3], ann_key="pragma_unroll_explicit", ann_val=1
)
# Schedule epilogue
if epilogue_info is not None:
epilogue = epilogue_info.block_rv
if is_broadcast_epilogue(sch, block, epilogue):
sch.reverse_compute_at(epilogue, bx)
sch.set_scope(block, 0, "shared")
_, _, *s = sch.get_loops(epilogue) # pylint: disable=invalid-name
_, ts = sch.split(sch.fuse(*s), factors=[None, TS])
sch.bind(ts, TAG_S)
else:
sch.reverse_compute_at(epilogue, bx, preserve_unit_loops=True)
ts_tile_s = sch.fuse(*sch.get_loops(epilogue)[1:])
ts_tile_s = sch.get_loops(epilogue)[-1]
ts, _ = sch.split(ts_tile_s, factors=[TS, None], preserve_unit_iters=True)
sch.bind(ts, TAG_S)
sch.set_scope(block, 0, "local")
return sch
# Specify the `len_tx` and `len_ty` according to the loop extent
batch, s, r, c = sch.get_loops(block=block)
_, len_s, len_r, len_c = (
get_extent(sch, batch),
get_extent(sch, s),
get_extent(sch, r),
get_extent(sch, c),
)
DEC_PACK = 8
SCALE_PACK = 4
if target.kind.name == "opencl" and (
("android" in str(target.host)) or ("adreno" in str(target.attrs))
):
TAG_S, TAG_R = "threadIdx.x", "threadIdx.y"
VEC_C = 8
UNROLL = 8
TS, TR = 64, 4
LOAD_V_SHARED = False
LOAD_V_VEC = 4
LOAD_V_TILE = 8
elif target.kind.name == "metal":
TAG_S, TAG_R = "threadIdx.x", "threadIdx.y"
VEC_C = 4
UNROLL = 8
TS, TR = 128, 4
LOAD_V_SHARED = False
LOAD_V_VEC = 4
LOAD_V_TILE = 4
else:
return None
if LOAD_V_SHARED is False:
LOAD_V_TILE = 1
if not isinstance(len_r, int) or len_r < LOAD_V_TILE * TR * SCALE_PACK * DEC_PACK:
return None
if not isinstance(len_s, int):
TS, TR = 256, 1
LOAD_V_SHARED = True
if isinstance(len_s, int) and len_s > 96000:
return None
_, TILE_R = (
1,
(
len_c
if len_c > 1
else max(get_max_factor(len_r, [TR * 1, TR * 2, TR * 4, TR * 8]) // TR, 1)
),
)
LOAD_V_VEC = min(get_max_factor(TILE_R, [1, 2, 4, 8]), LOAD_V_VEC)
VEC_LOAD = 1
return apply(
sch,
gemv=block,
TAG_S=TAG_S,
TAG_R=TAG_R,
TS=TS,
TR=TR,
SCALE_PACK=SCALE_PACK,
DEC_PACK=DEC_PACK,
VEC_LOAD=VEC_LOAD,
VEC_C=VEC_C,
LOAD_V_SHARED=LOAD_V_SHARED,
LOAD_V_VEC=LOAD_V_VEC,
UNROLL=UNROLL,
LOAD_V_TILE=LOAD_V_TILE,
)
def sch_outer_reduction_fallback( # pylint: disable=too-many-arguments, invalid-name, unused-argument
self,
sch: s_tir.Schedule,
target: Target,
block: s_tir.schedule.SBlockRV,
vector_input_buffers: list[tirx.Buffer],
epilogue_info: SBlockInfo | None,
):
"""Schedule the outer reduction block."""
# NOTE: Only Android is supported so far
if not (
target.kind.name == "opencl"
and (("android" in str(target.host)) or ("adreno" in str(target.attrs)))
):
return None
batch, s, r, c = sch.get_loops(block)
len_s = get_extent(sch, s)
# The config is designed for Adreno
LOAD_V_SHARED = 1
tx_len = 128
vec_len = (4 if len_s > 4096 else 2) if isinstance(len_s, int) else 1
inner_r = 4
bx, tx, vec = sch.split(s, factors=[None, tx_len, vec_len])
r0, r1 = sch.split(r, factors=[None, inner_r])
sch.bind(batch, "blockIdx.y")
sch.bind(bx, "blockIdx.x")
sch.bind(tx, "threadIdx.x")
sch.reorder(bx, tx, r0, r1, c, vec)
sch.annotate(tx, ann_key="pragma_auto_unroll_max_step", ann_val=8)
sch.annotate(tx, ann_key="pragma_unroll_explicit", ann_val=1)
if LOAD_V_SHARED:
V_shared = sch.cache_read(block, vector_input_buffers[0], storage_scope="shared")
sch.compute_at(V_shared, bx, preserve_unit_loops=True)
l = sch.get_loops(block=V_shared)[-1]
_, tx, vec_r = sch.split(l, factors=[None, tx_len, 8], preserve_unit_iters=True)
sch.bind(tx, "threadIdx.x")
sch.vectorize(vec_r)
sch.vectorize(vec)
# Schedule epilogue
if epilogue_info is not None:
sch.reverse_compute_at(epilogue_info.block_rv, bx, preserve_unit_loops=True)
ts_tile_s = sch.get_loops(epilogue_info.block_rv)[-1]
ts, vec = sch.split(ts_tile_s, factors=[tx_len, vec_len], preserve_unit_iters=True)
sch.bind(ts, "threadIdx.x")
sch.vectorize(vec)
sch.set_scope(block, 0, "local")
sch.decompose_reduction(block, r0)
return sch