Files
tilelang/testing/python/language/test_tilelang_language_atomic.py
T
Ziming Wang c63a2e7050 [BugFix][Transform] Keep shared FP32 atomics scalar on SM90 (#3129)
* [BugFix][Transform] Keep shared FP32 atomics scalar on SM90

Signed-off-by: ZenAlexa <zimingwang945@gmail.com>

* [Testing] Pin scalar atomic loop structure

Signed-off-by: ZenAlexa <zimingwang945@gmail.com>

* [Testing] Exercise lowered access_ptr atomics in vectorizer

Signed-off-by: ZenAlexa <zimingwang945@gmail.com>

---------

Signed-off-by: ZenAlexa <zimingwang945@gmail.com>
2026-09-07 11:37:13 +08:00

1420 lines
51 KiB
Python

import re
import pytest
import tilelang.testing
import tilelang.layout
import tilelang.language as T
import torch
from tilelang import tvm
# ======================= Thread-level atomic add =======================
@tilelang.jit
def atomic_add_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_add(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
for i, j in T.Parallel(block_M, block_N):
T.atomic_add(B[bx * block_M + i, by * block_N + j], A_shared[i, j])
return atomic_add
def run_atomic_add(K, M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_add_program(K, M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
ref_B = B + A.sum(dim=0)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_memory_order_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_with_memory_order(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
for i, j in T.Parallel(block_M, block_N):
T.atomic_add(B[bx * block_M + i, by * block_N + j], A_shared[i, j], memory_order="relaxed")
return atomic_with_memory_order
def run_atomic_memory_order(K, M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_memory_order_program(K, M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
ref_B = B + A.sum(dim=0)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_addx2_program(M, N, block_M, block_N, dtype=T.float16):
@T.prim_func
def atomic_addx2(A: T.Tensor((M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N // 2):
idx_i = bx * block_M + i
idx_j = by * block_N + j * 2
T.atomic_addx2(B[idx_i, idx_j], A[idx_i, idx_j])
return atomic_addx2
def run_atomic_addx2(M, N, block_M, block_N, dtype=T.float16):
kernel = atomic_addx2_program(M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(M, N, dtype=torch.float32).cuda().to(getattr(torch, dtype))
B = torch.zeros(M, N, dtype=torch.float32).cuda().to(getattr(torch, dtype))
ref_B = B.clone()
for i in range(M):
for j in range(0, N - 1, 2):
ref_B[i, j] += A[i, j]
ref_B[i, j + 1] += A[i, j + 1]
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_add_mixed_dtype_program(N, src_dtype, dst_dtype):
@T.prim_func
def atomic_add(Src: T.Tensor((N,), src_dtype), Out: T.Tensor((N,), dst_dtype)):
with T.Kernel(threads=1):
frag = T.alloc_fragment((N,), src_dtype)
for i in T.Parallel(N):
frag[i] = Src[i]
for i in T.Parallel(N):
T.atomic_add(Out[i], frag[i])
return atomic_add
def run_atomic_add_mixed_dtype(N, src_dtype, dst_dtype):
kernel = atomic_add_mixed_dtype_program(N, src_dtype, dst_dtype)
assert "AtomicAddx2" in kernel.get_kernel_source()
src = torch.arange(1, N + 1, dtype=getattr(torch, src_dtype)).cuda()
out = torch.zeros(N, dtype=getattr(torch, dst_dtype)).cuda()
kernel(src, out)
torch.testing.assert_close(out, src.to(getattr(torch, dst_dtype)), atol=1e-2, rtol=1e-2)
@tilelang.jit
def atomic_addx2_mixed_dtype_program(M, N, block_M, block_N, src_dtype, dst_dtype):
@T.prim_func
def atomic_addx2(A: T.Tensor((M, N), src_dtype), B: T.Tensor((M, N), dst_dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N // 2):
idx_i = bx * block_M + i
idx_j = by * block_N + j * 2
T.atomic_addx2(B[idx_i, idx_j], A[idx_i, idx_j])
return atomic_addx2
def run_atomic_addx2_mixed_dtype(M, N, block_M, block_N, src_dtype, dst_dtype):
kernel = atomic_addx2_mixed_dtype_program(M, N, block_M, block_N, src_dtype, dst_dtype)
assert "AtomicAddx2" in kernel.get_kernel_source()
A = torch.randn(M, N, dtype=getattr(torch, src_dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dst_dtype)).cuda()
ref_B = A.to(getattr(torch, dst_dtype))
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-2, rtol=1e-2)
@tilelang.jit
def atomic_different_memory_orders_program(M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_different_orders(
A: T.Tensor((M, N), dtype), B: T.Tensor((M, N), dtype), C: T.Tensor((M, N), dtype), D: T.Tensor((M, N), dtype)
):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N):
idx_i = bx * block_M + i
idx_j = by * block_N + j
if idx_i < M and idx_j < N:
val = A[idx_i, idx_j]
T.atomic_add(B[idx_i, idx_j], val, memory_order="release")
T.atomic_max(C[idx_i, idx_j], val, memory_order="relaxed")
T.atomic_min(D[idx_i, idx_j], val, memory_order="relaxed")
return atomic_different_orders
def run_atomic_different_memory_orders(M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_different_memory_orders_program(M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
C = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
D = torch.full((M, N), float("inf"), dtype=getattr(torch, dtype)).cuda()
kernel(A, B, C, D)
torch.testing.assert_close(B, A, atol=1e-3, rtol=1e-3)
torch.testing.assert_close(C, torch.maximum(torch.zeros_like(A), A))
torch.testing.assert_close(D, torch.minimum(torch.full_like(A, float("inf")), A))
@tilelang.jit
def atomic_addx4_program(M, N, block_M, block_N):
@T.prim_func
def atomic_addx4(A: T.Tensor((M, N), T.float32), B: T.Tensor((M, N), T.float32)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N // 4):
idx_i = bx * block_M + i
idx_j = by * block_N + j * 4
T.atomic_addx4(B[idx_i, idx_j], A[idx_i, idx_j])
return atomic_addx4
def run_atomic_addx4(M, N, block_M, block_N):
kernel = atomic_addx4_program(M, N, block_M, block_N)
import torch
A = torch.randn(M, N, dtype=torch.float32).cuda()
B = torch.zeros(M, N, dtype=torch.float32).cuda()
ref_B = B.clone()
for i in range(M):
for j in range(0, N - 3, 4):
ref_B[i, j] += A[i, j]
ref_B[i, j + 1] += A[i, j + 1]
ref_B[i, j + 2] += A[i, j + 2]
ref_B[i, j + 3] += A[i, j + 3]
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_addx4_sliced_dst_program(N, M, dtype=T.float32):
@T.prim_func
def atomic_addx4_sliced_dst(
idx: T.Tensor((N,), "int32"),
val: T.Tensor((N, 4), dtype),
dst: T.Tensor((M, 4), dtype),
):
with T.Kernel(1, threads=N):
t = T.get_thread_binding()
T.atomic_addx4(dst[idx[t], 0:4], val[t, 0:4])
return atomic_addx4_sliced_dst
def run_atomic_addx4_sliced_dst_compile(N, M, dtype=T.float32):
kernel = atomic_addx4_sliced_dst_program(N, M, dtype=dtype)
assert "AtomicAddx4" in kernel.get_kernel_source()
@tilelang.jit
def atomic_addx4_16bit_program(dtype, offset, nthreads):
@T.prim_func
def atomic_addx4(A: T.Tensor((16,), dtype), B: T.Tensor((16,), dtype)):
with T.Kernel(1, threads=nthreads):
T.atomic_addx4(B[offset], A[offset])
return atomic_addx4
def run_atomic_addx4_16bit(dtype, offset, nthreads):
kernel = atomic_addx4_16bit_program(dtype, offset, nthreads)
source = kernel.get_kernel_source()
assert "AtomicAddx4" in source
torch_dtype = getattr(torch, str(dtype))
A = torch.zeros(16, dtype=torch_dtype, device="cuda")
B_init = torch.zeros(16, dtype=torch_dtype, device="cuda")
A[offset : offset + 4] = torch.tensor([1, 2, 3, 4], dtype=torch_dtype, device="cuda")
B_init[offset : offset + 4] = torch.tensor([10, 20, 30, 40], dtype=torch_dtype, device="cuda")
B = B_init.clone()
ref_B = B_init.float()
ref_B[offset : offset + 4] += nthreads * A[offset : offset + 4].float()
kernel(A, B)
torch.testing.assert_close(B.float(), ref_B, atol=0, rtol=0)
@tilelang.jit
def atomic_return_prev_program(M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_with_return_prev(A: T.Tensor((M, N), dtype), B: T.Tensor((M, N), dtype), old_vals: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N):
idx_i = bx * block_M + i
idx_j = by * block_N + j
if idx_i < M and idx_j < N:
old_vals[idx_i, idx_j] = T.atomic_add(B[idx_i, idx_j], A[idx_i, idx_j], return_prev=True)
return atomic_with_return_prev
def run_atomic_return_prev(M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_return_prev_program(M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.ones(M, N, dtype=getattr(torch, dtype)).cuda() * 5.0
B = torch.ones(M, N, dtype=getattr(torch, dtype)).cuda() * 2.0
old_vals = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
initial_B = B.clone()
kernel(A, B, old_vals)
torch.testing.assert_close(old_vals, initial_B, atol=1e-3, rtol=1e-3)
torch.testing.assert_close(B, initial_B + A, atol=1e-3, rtol=1e-3)
@tilelang.jit
def tma_atomic_add_program(out, explicit_swizzle=False):
out: T.Tensor[(16, 16), T.float32]
with T.Kernel(
1,
):
out_shared = T.alloc_shared((16, 16), dtype=T.float32)
if explicit_swizzle:
T.annotate_layout({out_shared: tilelang.layout.make_swizzled_layout(out_shared)})
T.fill(out_shared, 1)
for _ in range(16):
T.atomic_add(out, out_shared, use_tma=True)
@tilelang.jit
def tma_atomic_add_uint64_program(out):
out: T.Tensor[(16, 16), T.uint64]
with T.Kernel(1):
out_shared = T.alloc_shared((16, 16), dtype=T.uint64)
T.fill(out_shared, 1)
for _ in range(4):
T.atomic_add(out, out_shared, use_tma=True)
@tilelang.jit
def tma_atomic_add_32b_swizzle_program(out):
out: T.Tensor[(16, 24), T.float32]
with T.Kernel(1):
out_shared = T.alloc_shared((16, 24), dtype=T.float32)
T.fill(out_shared, 1)
T.atomic_add(out, out_shared, use_tma=True)
def tma_atomic_add_compile_program(dtype, shape=(16, 16), explicit_layout=False):
@T.prim_func
def main(out: T.Tensor(shape, dtype)):
with T.Kernel(1):
out_shared = T.alloc_shared(shape, dtype=dtype)
if explicit_layout:
T.annotate_layout({out_shared: tilelang.layout.make_wgmma_swizzled_layout(out_shared)})
T.atomic_add(out, out_shared, use_tma=True)
return main
def lower_tma_atomic_add(dtype, arch="sm_90", shape=(16, 16), explicit_layout=False):
target = tvm.target.Target({"kind": "cuda", "arch": arch})
with target:
return tilelang.lower(
tma_atomic_add_compile_program(dtype, shape=shape, explicit_layout=explicit_layout),
target=target,
)
def get_tma_atomic_add_descriptor_args(artifact):
for func in artifact.host_mod.functions.values():
if func.attrs is None or "tma_descriptor_args" not in func.attrs:
continue
descriptors = list(func.attrs["tma_descriptor_args"].values())
assert len(descriptors) == 1
return list(descriptors[0])
raise AssertionError("TMA descriptor metadata not found")
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_tma_atomic_add():
out = torch.zeros((16, 16), dtype=torch.float32, device="cuda")
tma_atomic_add_program(out)
torch.testing.assert_close(out, torch.ones((16, 16), dtype=torch.float32, device="cuda") * 16)
kernel = tma_atomic_add_program.compile(out=T.Tensor[(16, 16), T.float32])
assert "tma_store_add" in kernel.get_kernel_source()
assert "desc" in kernel.get_kernel_source() # Ensure using cp.reduce.async.bulk.tensor
kernel_with_explicit_swizzle = tma_atomic_add_program.compile(out=T.Tensor[(16, 16), T.float32], explicit_swizzle=True)
# Ensure auto swizzled layout is applied
assert kernel.get_kernel_source() == kernel_with_explicit_swizzle.get_kernel_source()
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_tma_atomic_add_uint64_runtime():
out = torch.zeros((16, 16), dtype=torch.uint64, device="cuda")
tma_atomic_add_uint64_program(out)
torch.testing.assert_close(out, torch.full_like(out, 4), rtol=0, atol=0)
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_tma_atomic_add_wide_linear_layout_runtime():
rows, global_width, tile_width, col_offset = 8, 520, 512, 8
@tilelang.jit
def kernel(out):
out: T.Tensor[(rows, global_width), T.uint64]
with T.Kernel(1):
out_shared = T.alloc_shared((rows, tile_width), dtype=T.uint64)
T.fill(out_shared, 1)
T.atomic_add(
out[:, col_offset : col_offset + tile_width],
out_shared,
use_tma=True,
)
compiled = kernel.compile(out=T.Tensor[(rows, global_width), T.uint64])
source = compiled.get_kernel_source()
assert re.search(
r"for \(int \w+ = 0; \w+ < 2; \+\+\w+\) \{\n\s*tl::tma_store_add\(",
source,
)
out = torch.zeros((rows, global_width), dtype=torch.uint64, device="cuda")
compiled(out)
torch.cuda.synchronize()
assert torch.all(out[:, :col_offset] == 0)
assert torch.all(out[:, col_offset:] == 1)
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_tma_atomic_add_versioned_smem_slice_runtime():
"""A version slice of a wide linear buffer must stay contiguous under the
inferred layout, or the second TMA box silently reads the other version."""
rows, width = 8, 512
@tilelang.jit
def kernel(out):
out: T.Tensor[(rows, width), T.uint64]
with T.Kernel(1):
smem = T.alloc_shared((2, rows, width), dtype=T.uint64)
T.fill(smem, 7) # decoy in version 0
for i, j in T.Parallel(rows, width):
smem[1, i, j] = 1
T.atomic_add(out, smem[1, :, :], use_tma=True)
compiled = kernel.compile(out=T.Tensor[(rows, width), T.uint64])
source = compiled.get_kernel_source()
assert re.search(
r"for \(int \w+ = 0; \w+ < 2; \+\+\w+\) \{\n\s*tl::tma_store_add\(",
source,
)
out = torch.zeros((rows, width), dtype=torch.uint64, device="cuda")
compiled(out)
torch.cuda.synchronize()
torch.testing.assert_close(out, torch.ones_like(out), rtol=0, atol=0)
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_tma_atomic_add_32b_swizzle_runtime():
out = torch.zeros((16, 24), dtype=torch.float32, device="cuda")
tma_atomic_add_32b_swizzle_program(out)
torch.testing.assert_close(out, torch.ones_like(out), rtol=0, atol=0)
@tilelang.testing.requires_cuda
@pytest.mark.parametrize("dtype", [T.int16, T.int64, T.float64, T.float32x2])
def test_tma_atomic_add_rejects_unsupported_dtype(dtype):
with pytest.raises(
tvm.error.InternalError,
match=rf"TMA atomic add does not support dtype {dtype}.*supported scalar dtypes",
):
lower_tma_atomic_add(dtype)
@tilelang.testing.requires_cuda
@pytest.mark.parametrize("dtype", [T.float16, T.bfloat16, T.float32, T.int32, T.uint32, T.uint64])
def test_tma_atomic_add_accepts_ptx_dtype(dtype):
artifact = lower_tma_atomic_add(dtype)
assert "tma_store_add" in artifact.kernel_source
@tilelang.testing.requires_cuda
def test_tma_atomic_add_uint64_uses_linear_layout():
artifact = lower_tma_atomic_add(T.uint64)
descriptor_args = get_tma_atomic_add_descriptor_args(artifact)
# The final four descriptor arguments are interleave, swizzle, L2
# promotion, and OOB fill. uint64 intentionally uses no swizzle because
# its GEMM K-inner layout is not representable by TensorMap.
assert descriptor_args[-3].value == 0
@tilelang.testing.requires_cuda
def test_tma_atomic_add_splits_32b_swizzle_box():
artifact = lower_tma_atomic_add(T.float32, shape=(16, 24))
descriptor_args = get_tma_atomic_add_descriptor_args(artifact)
assert descriptor_args[-3].value == 1
assert re.search(
r"for \(int \w+ = 0; \w+ < 3; \+\+\w+\) \{\n\s*tl::tma_store_add",
artifact.kernel_source,
)
@tilelang.testing.requires_cuda
def test_tma_atomic_add_rejects_pre_hopper_target():
with pytest.raises(
tvm.error.InternalError,
match=r"TMA atomic add requires a CUDA target with TMA support \(SM90\+\)",
):
lower_tma_atomic_add(T.float32, arch="sm_80")
@tilelang.testing.requires_cuda
def test_tma_atomic_add_rejects_unencodable_explicit_layout():
with pytest.raises(
tvm.error.InternalError,
match=r"TMA atomic add cannot encode the shared layout.*not representable by a TensorMap descriptor",
):
lower_tma_atomic_add(T.uint64, explicit_layout=True)
def run_atomic_add_auto_vectorized(K, M, N, block_M, block_N, dtype=T.float32):
tilelang.disable_cache()
kernel = atomic_add_program(K, M, N, block_M, block_N, dtype=dtype)
assert "AtomicAddx4" in kernel.get_kernel_source()
@tilelang.jit
def atomic_add_auto_vectorized_unit_test(vec_size: int, dtype=T.float32):
@T.prim_func
def atomic_addx2(A: T.Tensor((vec_size,), dtype)):
with T.Kernel(threads=1):
A_local = T.alloc_fragment((vec_size,), dtype)
for i in T.Parallel(vec_size):
T.atomic_add(A[i], A_local[i])
return atomic_addx2
def run_atomic_add_auto_vectorized_unit_test(vec_size: int, dtype=T.float32):
kernel = atomic_add_auto_vectorized_unit_test(vec_size, dtype)
assert f"AtomicAddx{vec_size}" in kernel.get_kernel_source()
@tilelang.jit
def atomic_add_vectorized_memory_order_program(N, threads, memory_order, dtype=T.float16):
@T.prim_func
def atomic_add(X: T.Tensor((N,), dtype), Out: T.Tensor((N,), dtype)):
with T.Kernel(1, threads=threads):
T.atomic_add(Out[0:N], X[0:N], memory_order=memory_order)
return atomic_add
def run_atomic_add_vectorized_memory_order(N, threads, memory_order, memory_order_id, dtype=T.float16):
# A vectorized atomic add must carry the requested memory order, just like
# the scalar lowering of the same call does. Cache disabled because the key
# does not cover the native library by default, so a stale pre-fix kernel
# source would otherwise be served here.
tilelang.disable_cache()
try:
kernel = atomic_add_vectorized_memory_order_program(N, threads, memory_order, dtype=dtype)
wide_calls = re.findall(r"AtomicAddx\d\([^;]*\);", kernel.get_kernel_source())
assert wide_calls, f"expected a vectorized atomic add, got:\n{kernel.get_kernel_source()}"
for call in wide_calls:
assert call.endswith(f", {memory_order_id});"), f"{memory_order} dropped from vectorized atomic add: {call}"
# Each order takes a separately spelled asm string in the device helpers,
# so run the kernel to check this one actually computes the sum.
torch_dtype = getattr(torch, dtype)
X = torch.randn(N, dtype=torch_dtype).cuda()
Out = torch.zeros(N, dtype=torch_dtype).cuda()
kernel(X, Out)
torch.testing.assert_close(Out, X, atol=1e-2, rtol=1e-2)
finally:
tilelang.enable_cache()
@tilelang.jit
def atomic_add_complicated_parallel_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_add(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
for i, j in T.Parallel(block_M, block_N):
value = A_shared[i, j]
T.atomic_add(B[bx * block_M + i, by * block_N + j], value)
return atomic_add
def run_atomic_add_complicated_parallel(K, M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_add_complicated_parallel_program(K, M, N, block_M, block_N, dtype=dtype)
assert "float4 value" in kernel.get_kernel_source()
assert "AtomicAddx4" in kernel.get_kernel_source()
def test_atomic_memory_order():
run_atomic_memory_order(4, 64, 64, 16, 16)
@tilelang.testing.requires_cuda
def test_atomic_addx2_half():
run_atomic_addx2(32, 64, 8, 16, dtype=T.float16)
def test_atomic_addx2_float():
run_atomic_addx2(32, 64, 8, 16, dtype=T.float32)
@tilelang.testing.requires_cuda
def test_atomic_add_mixed_dtype_fp16():
run_atomic_add_mixed_dtype(8, T.float32, T.float16)
run_atomic_addx2_mixed_dtype(32, 64, 8, 16, T.float32, T.float16)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(7, 0)
def test_atomic_add_mixed_dtype_bf16():
run_atomic_add_mixed_dtype(8, T.float32, T.bfloat16)
run_atomic_addx2_mixed_dtype(32, 64, 8, 16, T.float32, T.bfloat16)
@tilelang.testing.requires_cuda
def test_atomic_different_memory_orders():
run_atomic_different_memory_orders(32, 32, 8, 8, dtype=T.float32)
run_atomic_different_memory_orders(32, 32, 8, 8, dtype=T.float16)
run_atomic_different_memory_orders(32, 32, 8, 8, dtype=T.bfloat16)
# ids match cuda::memory_order. Each one is a separately spelled asm string in
# the device helpers, so all three ordered spellings need exercising.
_ORDERED_MEMORY_ORDERS = [("acquire", 2), ("release", 3), ("acq_rel", 4)]
@tilelang.testing.requires_cuda
@pytest.mark.parametrize("memory_order, memory_order_id", _ORDERED_MEMORY_ORDERS)
def test_atomic_add_vectorized_preserves_memory_order(memory_order, memory_order_id):
run_atomic_add_vectorized_memory_order(64, 32, memory_order, memory_order_id, dtype=T.float16)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(8, 0)
@pytest.mark.parametrize("memory_order, memory_order_id", _ORDERED_MEMORY_ORDERS)
def test_atomic_add_vectorized_preserves_memory_order_bf16(memory_order, memory_order_id):
# bf16 takes a different device path depending on the target: below sm_90
# there is no ordered bf16 atomic in any width, so AtomicAddx2 falls back to
# fences around a relaxed add, while sm_90 uses the ordered instruction. A
# given run covers whichever side the test GPU selects.
run_atomic_add_vectorized_memory_order(64, 32, memory_order, memory_order_id, dtype=T.bfloat16)
def test_atomic_addx4():
run_atomic_addx4(16, 64, 4, 4)
def test_atomic_addx4_sliced_dst_compile():
run_atomic_addx4_sliced_dst_compile(32, 8)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(7, 0)
def test_atomic_addx4_16bit():
for dtype in (T.float16, T.bfloat16):
for offset in (0, 4):
run_atomic_addx4_16bit(dtype, offset=offset, nthreads=2)
def test_atomic_return_prev():
run_atomic_return_prev(32, 32, 8, 8)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(7, 0)
@pytest.mark.parametrize("dtype", [T.float16, T.bfloat16])
def test_atomic_return_prev_16bit(dtype):
run_atomic_return_prev(32, 32, 8, 8, dtype=dtype)
def test_atomic_add():
run_atomic_add(8, 128, 128, 32, 32)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_atomic_add_auto_vectorized():
run_atomic_add_auto_vectorized(8, 128, 128, 32, 32, dtype=T.float32)
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_atomic_add_auto_vectorized_unit_test():
run_atomic_add_auto_vectorized_unit_test(2, dtype=T.float32)
run_atomic_add_auto_vectorized_unit_test(4, dtype=T.float32)
run_atomic_add_auto_vectorized_unit_test(2, dtype=T.float16)
run_atomic_add_auto_vectorized_unit_test(2, dtype=T.bfloat16)
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_atomic_add_complicated_parallel():
run_atomic_add_complicated_parallel(8, 128, 128, 32, 32, dtype=T.float32)
# ======================= Tile-level atomic add =======================
@tilelang.jit
def tile_atomic_add_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_add(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
T.atomic_add(B[bx * block_M, by * block_N], A_shared)
return atomic_add
def run_tile_atomic_add(K, M, N, block_M, block_N, dtype=T.float32):
kernel = tile_atomic_add_program(K, M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
ref_B = B + A.sum(dim=0)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def tile_atomic_add_expr_program(M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_add(A: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
T.atomic_add(A[bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], 1.0)
return atomic_add
def run_tile_atomic_add_expr(M, N, block_M, block_N, dtype=T.float32):
kernel = tile_atomic_add_expr_program(M, N, block_M, block_N, dtype=dtype)
import torch
def ref_program(A):
for i in range(M):
for j in range(N):
A[i, j] += 1
A = torch.zeros(M, N, dtype=torch.float32).cuda()
ref_A = A.clone()
ref_program(ref_A)
kernel(A)
torch.testing.assert_close(A, ref_A, atol=1e-3, rtol=1e-3)
@tilelang.jit
def tile_atomic_add_scalar_program(dtype=T.float32):
@T.prim_func
def atomic_add(A: T.Tensor((1), dtype), B: T.Tensor((1), dtype)):
with T.Kernel(
1,
) as _:
A_local = T.alloc_local([1], dtype)
T.copy(A, A_local)
T.clear(B)
T.atomic_add(B, A_local)
T.atomic_add(B, 1)
return atomic_add
def run_tile_atomic_add_scalar(dtype=T.float32):
kernel = tile_atomic_add_scalar_program(dtype=dtype)
import torch
def ref_program(A, B):
B[0] = A[0] + 1
A = torch.randn(1, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(1, dtype=getattr(torch, dtype)).cuda()
ref_B = B.clone()
ref_program(A, ref_B)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
def test_tile_atomic_add():
run_tile_atomic_add(8, 128, 128, 32, 32)
def test_tile_atomic_add_expr():
run_tile_atomic_add_expr(128, 128, 32, 32)
def test_tile_atomic_add_scalar():
run_tile_atomic_add_scalar()
# ======================= Thread-level atomic max/min/load store =======================
@tilelang.jit
def atomic_max_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_max(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
for i, j in T.Parallel(block_M, block_N):
T.atomic_max(B[bx * block_M + i, by * block_N + j], A_shared[i, j])
return atomic_max
def run_atomic_max(K, M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_max_program(K, M, N, block_M, block_N, dtype=dtype)
import torch
def ref_program(A, B):
for k in range(K):
for i in range(M):
for j in range(N):
B[i, j] = max(B[i, j], A[k, i, j])
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
ref_B = B.clone()
ref_program(A, ref_B)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_min_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_min(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
for i, j in T.Parallel(block_M, block_N):
T.atomic_min(B[bx * block_M + i, by * block_N + j], A_shared[i, j])
return atomic_min
def run_atomic_min(K, M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_min_program(K, M, N, block_M, block_N, dtype=dtype)
import torch
def ref_program(A, B):
for k in range(K):
for i in range(M):
for j in range(N):
B[i, j] = min(B[i, j], A[k, i, j])
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.full((M, N), float("inf"), dtype=getattr(torch, dtype)).cuda()
ref_B = B.clone()
ref_program(A, ref_B)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def atomic_load_store_program(M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_load_store(A: T.Tensor((M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
for i, j in T.Parallel(block_M, block_N):
idx_i = bx * block_M + i
idx_j = by * block_N + j
if idx_i < M and idx_j < N:
val = T.atomic_load(A[idx_i, idx_j])
T.atomic_store(B[idx_i, idx_j], val)
return atomic_load_store
def run_atomic_load_store(M, N, block_M, block_N, dtype=T.float32):
kernel = atomic_load_store_program(M, N, block_M, block_N, dtype=dtype)
import torch
A = torch.randn(M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.zeros(M, N, dtype=getattr(torch, dtype)).cuda()
kernel(A, B)
torch.testing.assert_close(B, A, atol=1e-3, rtol=1e-3)
def _build_atomic_load_with_memory_order(memory_order):
@T.prim_func
def kernel(source: T.Tensor((1,), T.int32), output: T.Tensor((1,), T.int32)):
with T.Kernel(1, threads=1):
output[0] = T.atomic_load(source[0], memory_order=memory_order)
return kernel
def _build_atomic_store_with_memory_order(memory_order):
@T.prim_func
def kernel(destination: T.Tensor((1,), T.int32)):
with T.Kernel(1, threads=1):
T.atomic_store(destination[0], 1, memory_order=memory_order)
return kernel
@pytest.mark.parametrize("memory_order", ["relaxed", "consume", "acquire", "seq_cst"])
def test_atomic_load_accepts_valid_memory_orders(memory_order):
assert _build_atomic_load_with_memory_order(memory_order) is not None
@pytest.mark.parametrize("memory_order", ["release", "acq_rel", "invalid"])
def test_atomic_load_rejects_unsupported_memory_orders(memory_order):
with pytest.raises(ValueError, match="atomic_load does not support memory_order"):
_build_atomic_load_with_memory_order(memory_order)
@pytest.mark.parametrize("memory_order", ["relaxed", "release", "seq_cst"])
def test_atomic_store_accepts_valid_memory_orders(memory_order):
assert _build_atomic_store_with_memory_order(memory_order) is not None
@pytest.mark.parametrize("memory_order", ["consume", "acquire", "acq_rel", "invalid"])
def test_atomic_store_rejects_unsupported_memory_orders(memory_order):
with pytest.raises(ValueError, match="atomic_store does not support memory_order"):
_build_atomic_store_with_memory_order(memory_order)
@tilelang.testing.requires_cuda
def test_atomic_or_codegen():
@T.prim_func
def atomic_or_kernel(A: T.Tensor((1,), T.int32), mask: T.int32):
with T.Kernel(1, threads=32):
T.atomic_or(A[0], mask, memory_order="release")
kernel = tilelang.compile(atomic_or_kernel, out_idx=[0], target="cuda")
source = kernel.get_kernel_source()
assert "AtomicOr" in source
def test_atomic_max():
run_atomic_max(4, 64, 64, 16, 16)
def test_atomic_min():
run_atomic_min(4, 64, 64, 16, 16)
# ======== fp16/bf16 scalar max/min value-dtype conversion (issue #2758) ========
def run_atomic_max_scalar_literal(dtype):
@tilelang.jit
def wrapper():
@T.prim_func
def kernel(dst: T.Tensor((1,), dtype)):
with T.Kernel(1, threads=1):
T.atomic_max(dst[0], 42.0) # python float literal is fp32
return kernel
kernel = wrapper()
dst = torch.full((1,), -1e4, device="cuda", dtype=getattr(torch, dtype))
kernel(dst)
torch.testing.assert_close(dst, torch.full((1,), 42.0, device="cuda", dtype=getattr(torch, dtype)))
def run_atomic_min_scalar_literal(dtype):
@tilelang.jit
def wrapper():
@T.prim_func
def kernel(dst: T.Tensor((1,), dtype)):
with T.Kernel(1, threads=1):
T.atomic_min(dst[0], 42.0) # python float literal is fp32
return kernel
kernel = wrapper()
dst = torch.full((1,), 1e4, device="cuda", dtype=getattr(torch, dtype))
kernel(dst)
torch.testing.assert_close(dst, torch.full((1,), 42.0, device="cuda", dtype=getattr(torch, dtype)))
@tilelang.testing.requires_cuda
def test_atomic_max_scalar_fp16():
run_atomic_max_scalar_literal("float16")
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(8, 0)
def test_atomic_max_scalar_bf16():
run_atomic_max_scalar_literal("bfloat16")
@tilelang.testing.requires_cuda
def test_atomic_min_scalar_fp16():
run_atomic_min_scalar_literal("float16")
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(8, 0)
def test_atomic_min_scalar_bf16():
run_atomic_min_scalar_literal("bfloat16")
def test_atomic_load_store():
run_atomic_load_store(64, 64, 16, 16)
# ======================= Tile-level atomic max/min =======================
@tilelang.jit
def tile_atomic_max_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def tile_atomic_max(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
T.atomic_max(B[bx * block_M, by * block_N], A_shared)
return tile_atomic_max
def run_tile_atomic_max(K, M, N, block_M, block_N, dtype=T.float32):
kernel = tile_atomic_max_program(K, M, N, block_M, block_N, dtype=dtype)
def ref_program(A, B):
for k in range(K):
for i in range(M):
for j in range(N):
B[i, j] = max(B[i, j], A[k, i, j])
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.full((M, N), float("-inf"), dtype=getattr(torch, dtype)).cuda()
ref_B = B.clone()
ref_program(A, ref_B)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def tile_atomic_min_program(K, M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def tile_atomic_min(A: T.Tensor((K, M, N), dtype), B: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), K, threads=32) as (bx, by, bz):
A_shared = T.alloc_shared((block_M, block_N), dtype)
T.copy(A[bz, bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], A_shared)
T.atomic_min(B[bx * block_M, by * block_N], A_shared)
return tile_atomic_min
def run_tile_atomic_min(K, M, N, block_M, block_N, dtype=T.float32):
kernel = tile_atomic_min_program(K, M, N, block_M, block_N, dtype=dtype)
def ref_program(A, B):
for k in range(K):
for i in range(M):
for j in range(N):
B[i, j] = min(B[i, j], A[k, i, j])
A = torch.randn(K, M, N, dtype=getattr(torch, dtype)).cuda()
B = torch.full((M, N), float("inf"), dtype=getattr(torch, dtype)).cuda()
ref_B = B.clone()
ref_program(A, ref_B)
kernel(A, B)
torch.testing.assert_close(B, ref_B, atol=1e-3, rtol=1e-3)
@tilelang.jit
def tile_atomic_max_expr_program(M, N, block_M, block_N, dtype=T.float32):
@T.prim_func
def atomic_max(A: T.Tensor((M, N), dtype)):
with T.Kernel(T.ceildiv(M, block_M), T.ceildiv(N, block_N), threads=32) as (bx, by):
T.atomic_max(A[bx * block_M : (bx + 1) * block_M, by * block_N : (by + 1) * block_N], 0.5)
return atomic_max
def run_tile_atomic_max_expr(M, N, block_M, block_N, dtype=T.float32):
kernel = tile_atomic_max_expr_program(M, N, block_M, block_N, dtype=dtype)
import torch
def ref_program(A):
for i in range(M):
for j in range(N):
A[i, j] = max(A[i, j], 0.5)
A = torch.randn(M, N, dtype=torch.float32).cuda()
ref_A = A.clone()
ref_program(ref_A)
kernel(A)
torch.testing.assert_close(A, ref_A, atol=1e-3, rtol=1e-3)
def test_tile_atomic_max():
run_tile_atomic_max(8, 128, 128, 32, 32)
def test_tile_atomic_min():
run_tile_atomic_min(8, 128, 128, 32, 32)
def test_tile_atomic_max_expr():
run_tile_atomic_max_expr(128, 128, 32, 32)
def atomic_scalar_return_prev_program(op_name, val):
atom = getattr(T, op_name)
@T.prim_func
def main(Dst: T.Tensor((1,), "float32"), Prev: T.Tensor((1,), "float32")):
with T.Kernel(1, threads=1):
Prev[0] = atom(Dst[0], val, return_prev=True)
return main
def run_atomic_scalar_return_prev(op_name):
# Pick val so the op actually changes dst (else a silent no-op would still
# pass): max needs val > dst, min needs val < dst.
val = 5.0 if op_name == "atomic_max" else 1.0
kernel = tilelang.compile(atomic_scalar_return_prev_program(op_name, val))
dst = torch.tensor([3.0], dtype=torch.float32).cuda()
prev = torch.zeros(1, dtype=torch.float32).cuda()
kernel(dst, prev)
assert prev.item() == 3.0, f"{op_name} return_prev should be the old value"
expected = max(3.0, val) if op_name == "atomic_max" else min(3.0, val)
assert dst.item() == expected, f"{op_name} should still update Dst"
@tilelang.testing.requires_cuda
def test_atomic_scalar_return_prev():
run_atomic_scalar_return_prev("atomic_max")
run_atomic_scalar_return_prev("atomic_min")
def atomic_addx2_return_prev_program(dtype=T.float32):
@T.prim_func
def main(Dst: T.Tensor((2,), dtype), Val: T.Tensor((2,), dtype), Prev: T.Tensor((2,), dtype)):
with T.Kernel(1, threads=1):
Prev[0:2] = T.atomic_addx2(Dst[0:2], Val[0:2], return_prev=True)
return main
def atomic_addx2_return_prev_let_bound_program(dtype=T.float32):
@T.prim_func
def main(Dst: T.Tensor((2,), dtype), Val: T.Tensor((2,), dtype), Prev: T.Tensor((2,), dtype)):
with T.Kernel(1, threads=1):
dst = Dst[0:2]
val = Val[0:2]
Prev[0:2] = T.atomic_addx2(dst, val, return_prev=True)
return main
def atomic_addx2_return_prev_ramp_program(dtype=T.float32):
@T.prim_func
def main(Dst: T.Tensor((2,), dtype), Val: T.Tensor((2,), dtype), Prev: T.Tensor((2,), dtype)):
with T.Kernel(1, threads=1):
Prev[0:2] = T.atomic_addx2(
Dst[T.Ramp(0, 1, 2)],
Val[T.Ramp(0, 1, 2)],
return_prev=True,
)
return main
def atomic_addx4_return_prev_program(dtype=T.float32):
@T.prim_func
def main(Dst: T.Tensor((4,), dtype), Val: T.Tensor((4,), dtype), Prev: T.Tensor((4,), dtype)):
with T.Kernel(1, threads=1):
Prev[0:4] = T.atomic_addx4(Dst[0:4], Val[0:4], return_prev=True)
return main
def test_atomic_addx2_return_prev_accepts_sliced_destination():
atomic_addx2_return_prev_program(T.float32)
def test_atomic_addx2_return_prev_accepts_let_bound_slice():
atomic_addx2_return_prev_let_bound_program(T.float32)
def test_atomic_addx2_return_prev_accepts_ramp():
atomic_addx2_return_prev_ramp_program(T.float32)
def test_atomic_addx2_return_prev():
kernel = tilelang.compile(atomic_addx2_return_prev_let_bound_program(T.float32))
assert "AtomicAddx2Ret" in kernel.get_kernel_source()
dst = torch.tensor([1.0, 2.0], dtype=torch.float32).cuda()
val = torch.tensor([10.0, 20.0], dtype=torch.float32).cuda()
prev = torch.zeros(2, dtype=torch.float32).cuda()
kernel(dst, val, prev)
torch.testing.assert_close(prev, torch.tensor([1.0, 2.0], device="cuda"))
torch.testing.assert_close(dst, torch.tensor([11.0, 22.0], device="cuda"))
def test_atomic_addx4_return_prev():
kernel = tilelang.compile(atomic_addx4_return_prev_program(T.float32))
assert "AtomicAddx4Ret" in kernel.get_kernel_source()
dst = torch.tensor([1.0, 2.0, 3.0, 4.0], dtype=torch.float32).cuda()
val = torch.tensor([10.0, 20.0, 30.0, 40.0], dtype=torch.float32).cuda()
prev = torch.zeros(4, dtype=torch.float32).cuda()
kernel(dst, val, prev)
torch.testing.assert_close(prev, torch.tensor([1.0, 2.0, 3.0, 4.0], device="cuda"))
torch.testing.assert_close(dst, torch.tensor([11.0, 22.0, 33.0, 44.0], device="cuda"))
def run_atomic_addx2_return_prev_16bit(dtype, torch_dtype):
# The 16-bit packed 2-lane vector is stored as uint1 in codegen, while
# AtomicAddx2Ret returns the native __half2 / __nv_bfloat162. The ret path
# must bridge with tl::to_uint1 so the store LHS (uint1) matches; otherwise
# nvcc fails with `no operator "=" ... uint1 = half2`.
kernel = tilelang.compile(atomic_addx2_return_prev_program(dtype))
src = kernel.get_kernel_source()
assert "tl::to_uint1(AtomicAddx2Ret" in src, src
dst = torch.tensor([1.0, 2.0], dtype=torch_dtype).cuda()
val = torch.tensor([10.0, 20.0], dtype=torch_dtype).cuda()
prev = torch.zeros(2, dtype=torch_dtype).cuda()
kernel(dst, val, prev)
torch.testing.assert_close(prev, torch.tensor([1.0, 2.0], dtype=torch_dtype, device="cuda"))
torch.testing.assert_close(dst, torch.tensor([11.0, 22.0], dtype=torch_dtype, device="cuda"))
@tilelang.testing.requires_cuda
def test_atomic_addx2_return_prev_fp16():
run_atomic_addx2_return_prev_16bit(T.float16, torch.float16)
@tilelang.testing.requires_cuda
def test_atomic_addx2_return_prev_bf16():
run_atomic_addx2_return_prev_16bit(T.bfloat16, torch.bfloat16)
def run_atomic_addx4_return_prev_16bit(dtype, torch_dtype):
# There is NO single-atomic fp16x4/bf16x4 add in hardware (PTX vector
# atomic .v4 tops out at .f16x2 for 16-bit types). The x4 ret path realizes
# the quad as two per-pair AtomicAddx2Ret calls and returns them packed as
# a uint2 (a half4/bf16x4 is stored as uint2), matching the store LHS. This
# is per-pair atomic, not whole-quad -- the same contract as the fp32-x4
# scalar fallback.
kernel = tilelang.compile(atomic_addx4_return_prev_program(dtype))
src = kernel.get_kernel_source()
assert "AtomicAddx4Ret" in src, src
dst = torch.tensor([1.0, 2.0, 3.0, 4.0], dtype=torch_dtype).cuda()
val = torch.tensor([10.0, 20.0, 30.0, 40.0], dtype=torch_dtype).cuda()
prev = torch.zeros(4, dtype=torch_dtype).cuda()
kernel(dst, val, prev)
torch.testing.assert_close(prev, torch.tensor([1.0, 2.0, 3.0, 4.0], dtype=torch_dtype, device="cuda"))
torch.testing.assert_close(dst, torch.tensor([11.0, 22.0, 33.0, 44.0], dtype=torch_dtype, device="cuda"))
@tilelang.testing.requires_cuda
def test_atomic_addx4_return_prev_fp16():
run_atomic_addx4_return_prev_16bit(T.float16, torch.float16)
@tilelang.testing.requires_cuda
def test_atomic_addx4_return_prev_bf16():
run_atomic_addx4_return_prev_16bit(T.bfloat16, torch.bfloat16)
# ======================= Atomic return value materialization =======================
@tilelang.jit
def atomic_add_return_prev_compaction_program(n, cap, block, dtype=T.float32):
@T.prim_func
def compact_positive(
x: T.Tensor((n,), dtype),
out: T.Tensor((cap,), T.int32),
counter: T.Tensor((1,), T.int32),
):
with T.Kernel(T.ceildiv(n, block), threads=block) as bx:
tx = T.get_thread_binding()
i = bx * block + tx
if i < n and x[i] > 0:
# Side-effecting bind: the returned previous counter value is
# used at TWO sites (bound check + store index). The lowering
# must materialize the atomic exactly once; replaying it per
# use site executes the atomic twice per element.
pos = T.atomic_add(counter[0], 1, return_prev=True)
if pos < cap:
out[pos] = i
return compact_positive
def test_atomic_add_return_prev_materialized_once():
n, cap, block = 4096, 4096, 256
kernel = atomic_add_return_prev_compaction_program(n, cap, block)
# Static check: the returned atomic must appear exactly once in the
# generated source (regression: duplicated AtomicAddRet calls).
assert kernel.get_kernel_source().count("AtomicAddRet") == 1
# Functional check: with all-positive input the counter must equal n and
# out must be a permutation of 0..n-1 (no unwritten slots).
x = torch.ones(n, dtype=torch.float32).cuda()
out = torch.full((cap,), -1, dtype=torch.int32).cuda()
counter = torch.zeros(1, dtype=torch.int32).cuda()
kernel(x, out, counter)
torch.cuda.synchronize()
assert counter.item() == n, f"atomic executed {counter.item()} times, expected {n}"
assert (out < 0).sum().item() == 0, "unwritten slots: atomic return value was re-evaluated"
assert torch.equal(out.sort().values.long(), torch.arange(n).cuda())
# ======================= Contended scalar atomic add =======================
@tilelang.jit
def atomic_add_contended_program(N, threads, dtype):
@T.prim_func
def atomic_add_contended(A: T.Tensor((N,), dtype), Out: T.Tensor((1,), dtype)):
with T.Kernel(1, threads=threads) as _:
for i in T.Parallel(N):
T.atomic_add(Out[0], A[i])
return atomic_add_contended
def run_atomic_add_contended(N, threads, dtype):
kernel = atomic_add_contended_program(N, threads, dtype)
# Every thread targets the same cell, so a non-atomic read-modify-write
# loses updates. Ones keep every partial sum exactly representable.
a = torch.ones(N, dtype=getattr(torch, dtype)).cuda()
out = torch.zeros(1, dtype=getattr(torch, dtype)).cuda()
kernel(a, out)
assert float(out[0]) == float(N), f"lost updates: got {float(out[0])}, expected {N}"
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(7, 0)
def test_atomic_add_contended_bf16():
# bf16 is the dtype whose pre-SM80 add is a CAS loop; float32 contention is
# already covered by the multi-block test_atomic_add above.
run_atomic_add_contended(128, 128, T.bfloat16)
@tilelang.jit
def atomic_add_fp32_shared_sm90_program(N, threads):
@T.prim_func
def atomic_add_fp32_shared_sm90(A: T.Tensor((N,), T.float32), Out: T.Tensor((N,), T.float32)):
with T.Kernel(1, threads=threads):
shared = T.alloc_shared((N,), T.float32)
for i in T.Parallel(N):
shared[i] = T.float32(0)
for i in T.Parallel(N):
T.atomic_add(shared[i], A[i])
for i in T.Parallel(N):
Out[i] = shared[i]
return atomic_add_fp32_shared_sm90
@tilelang.testing.requires_cuda
@tilelang.testing.requires_cuda_compute_version_ge(9, 0)
def test_atomic_add_fp32_shared_stays_scalar_on_sm90():
n = 256
kernel = atomic_add_fp32_shared_sm90_program(n, 128)
source = kernel.get_kernel_source()
assert "AtomicAdd(" in source
assert "AtomicAddx2(" not in source
assert "AtomicAddx4(" not in source
a = torch.arange(n, dtype=torch.float32, device="cuda")
out = torch.empty_like(a)
kernel(a, out)
torch.testing.assert_close(out, a, atol=0, rtol=0)
@tilelang.jit(target={"kind": "cuda", "arch": "sm_75"})
def atomic_add_bf16_sm75_program(N):
@T.prim_func
def atomic_add_bf16_sm75(A: T.Tensor((N,), T.bfloat16), B: T.Tensor((N,), T.bfloat16), Prev: T.Tensor((N,), T.bfloat16)):
with T.Kernel(1, threads=32) as _:
# Outside a parallel loop, so it stays scalar instead of packed.
T.atomic_add(B[1], A[1])
for i in T.Parallel(N // 2):
T.atomic_addx2(B[i * 2], A[i * 2])
for i in T.Parallel(N // 4):
T.atomic_addx4(B[i * 4], A[i * 4])
Prev[0] = T.atomic_add(B[0], A[0], return_prev=True)
Prev[0:2] = T.atomic_addx2(B[0:2], A[0:2], return_prev=True)
Prev[0:4] = T.atomic_addx4(B[0:4], A[0:4], return_prev=True)
return atomic_add_bf16_sm75
@tilelang.testing.requires_cuda
def test_atomic_add_bf16_compiles_for_sm75():
"""The native __nv_bfloat16 atomicAdd and `atom.*.v2.bf16` are SM80+, and
atomic.h reaches every generated kernel, so the pre-SM80 fallbacks must keep
compiling. Pinned with an explicit sm_75 target because the tests above use
the runner's native target and would miss this fallback on a modern GPU."""
source = atomic_add_bf16_sm75_program(64).get_kernel_source()
# Auto-vectorization rewrites scalar adds into packed ones, so check the
# kernel above still reaches each fallback.
for helper in (
"AtomicAdd(",
"AtomicAddx2(",
"AtomicAddx4(",
"AtomicAddRet(",
"AtomicAddx2Ret(",
"AtomicAddx4Ret(",
):
assert helper in source, f"{helper} not exercised by the sm_75 kernel"
if __name__ == "__main__":
tilelang.testing.main()