Files
tilelang/testing/python/language/test_tilelang_language_clear.py
T
Chennes 74d4f0ed66 [BugFix] Fix make_int sign-extending negative int8 lanes (#2438)
T.fill of an int8 buffer with a negative scalar (other than -1) silently
wrote only 1 of every 4 elements correctly and clobbered the other 3 to
-1. The vectorized fill packs four int8 lanes into one 32-bit store via
make_int(v,v,v,v); a negative signed char is integer-promoted to int and
sign-extended before the shifts/OR, so its high 1-bits flood the
neighbouring lanes (e.g. make_int(-7,-7,-7,-7) returned 0xFFFFFFF9 =
[-7,-1,-1,-1]).

Build the packed value from explicit unsigned bytes so the sign-extension
bits cannot leak across lanes. Add an int8 negative-fill regression test.

Fixes #2427
2026-06-23 14:40:11 +08:00

108 lines
3.5 KiB
Python

import tilelang
import tilelang.testing
import tilelang.language as T
import pytest
import torch
from tilelang.contrib import nvcc
# add decorator @tilelang.jit if you want to return a torch function
# @tilelang.jit
def matmul(M, N, K, block_M, block_N, block_K, dtype=T.float16, accum_dtype=T.float32):
@T.prim_func
def main(
A: T.Tensor((M, K), dtype),
B: T.Tensor((N, K), dtype),
C: T.Tensor((M, N), dtype),
):
# Initialize Kernel Context
with T.Kernel(T.ceildiv(N, block_N), T.ceildiv(M, block_M), threads=128) as (bx, by):
A_shared = T.alloc_shared((block_M, block_K), dtype)
B_shared = T.alloc_shared((block_N, block_K), dtype)
C_local = T.alloc_fragment((block_M, block_N), accum_dtype)
T.clear(C_local)
for ko in T.Pipelined(T.ceildiv(K, block_K), num_stages=0):
# Copy tile of A
# This is a sugar syntax for parallelized copy
T.copy(A[by * block_M, ko * block_K], A_shared)
T.clear(A_shared)
# Demonstrate parallelized copy from global to shared for B
T.copy(B[bx * block_N, ko * block_K], B_shared)
# Perform a tile-level GEMM on the shared buffers
# Currently we dispatch to the cute/hip on Nvidia/AMD GPUs
T.gemm(A_shared, B_shared, C_local, transpose_B=True)
# Copy result back to global memory
T.copy(C_local, C[by * block_M, bx * block_N])
return main
def run_matmul(M, N, K, block_M, block_N, block_K, dtype=T.float16, accum_dtype=T.float32):
program = matmul(M, N, K, block_M, block_N, block_K, dtype, accum_dtype)
kernel = tilelang.compile(program, out_idx=[2])
import torch
a = torch.randn((M, K), dtype=dtype.as_torch()).cuda()
b = torch.randn((N, K), dtype=dtype.as_torch()).cuda()
c = kernel(a, b)
assert torch.allclose(c, torch.zeros_like(c))
def test_matmul():
run_matmul(1024, 1024, 1024, 128, 128, 32)
@tilelang.testing.requires_cuda_compute_version(10)
def test_shared_fill_cast_zero_uses_st_bulk():
if nvcc.get_cuda_version() < (12, 8):
pytest.skip("st.bulk shared lowering requires CUDA toolkit >= 12.8")
@T.prim_func
def main(out: T.Tensor((128,), T.float32)):
with T.Kernel(1, threads=128):
smem = T.alloc_shared((128,), T.float32)
for i in T.Parallel(128):
smem[i] = T.float32(1.0)
T.fill(smem, T.cast(0, T.float32))
T.copy(smem, out)
kernel = tilelang.compile(main, target="cuda")
assert "tl::st_bulk_shared<512, 0>" in kernel.get_kernel_source()
out = torch.empty((128,), dtype=torch.float32, device="cuda")
kernel(out)
torch.cuda.synchronize()
assert torch.allclose(out, torch.zeros_like(out))
@tilelang.testing.requires_cuda
def test_fill_int8_negative():
M, N = 8, 128
def program(value):
@T.prim_func
def main(out: T.Tensor((M, N), "int8")):
with T.Kernel(1, threads=128):
smem = T.alloc_shared((M, N), "int8")
T.fill(smem, value)
T.copy(smem, out)
return main
for value in (-7, -128, -1, 5):
kernel = tilelang.compile(program(value), out_idx=[0])
out = kernel()
torch.cuda.synchronize()
ref = torch.full((M, N), value, dtype=torch.int8, device="cuda")
torch.testing.assert_close(out, ref)
if __name__ == "__main__":
test_matmul()