Files
triton/python/examples/tutorials/mat_mul.py
2021-07-27 12:38:48 -07:00

85 lines
2.1 KiB
Python

import torch
import triton
class _dot(torch.autograd.Function):
src = """
__global__ void dot(TYPE *A, TYPE *B, TYPE *C, int M, int N, int K,
int lda __multipleof(8), int ldb __multipleof(8), int ldc __multipleof(8)) {
int pm = get_program_id(0);
int pn = get_program_id(1);
// ranges
int rm[TM] = pm * TM + 0 ... TM;
int rn[TN] = pn * TN + 0 ... TN;
int rk[TK] = 0 ... TK;
// accumulator
float c[TM, TN] = 0;
// pointers
TYPE* pa[TM, TK] = A + rk[newaxis, :] * 1 + rm[:, newaxis] * lda;
TYPE* pb[TK, TN] = B + rk[:, newaxis] * ldb + rn[newaxis, :] * 1;
for(int k=K; k>0; k-=TK) {
TYPE a[TM, TK] = *pa;
TYPE b[TK, TN] = *pb;
c += a @ b;
pa = pa + TK * 1;
pb = pb + TK * ldb;
}
TYPE* pc[TM,TN] = C + rn[newaxis, :] + rm[:,newaxis] * ldc;
*pc = c;
}
"""
@staticmethod
def forward(ctx, a, b):
c = _dot._call(a,b)
return c
kernel = dict()
@staticmethod
def _call(a, b):
# shapes
M, K = a.shape
K, N = b.shape
# leading dimension
lda = K
ldb = N
ldc = N
dtype = a.dtype
# create kernel if necessary
if dtype not in _dot.kernel:
defines = {
'TYPE' : dtype,
'TM' : [64, 128],
'TN' : [64, 128],
'TK' : [8, 16],
}
_dot.kernel[dtype] = triton.kernel(_dot.src, num_warps=[2, 4], defines=defines)
kernel = _dot.kernel[dtype]
# allocate output
c = triton.empty([M,N], dtype=dtype)
# enqueue
grid = lambda opt: [triton.cdiv(M, opt.d('TM')),
triton.cdiv(N, opt.d('TN'))]
kernel(a, b, c, M, N, K, lda, ldb, ldc, grid=grid)
return c
dot = _dot.apply
torch.manual_seed(0)
M, N, K = 128, 512, 256
a = torch.rand((M, K)).cuda()
b = torch.rand((K, N)).cuda()
zc = torch.matmul(a,b)
zc_ = dot(a,b)
print(torch.allclose(zc, zc_))