GPUCodeForces/S1/uucoco_#20/SoftExponential_cuda.py

133 lines
4.2 KiB
Python

import torch
import torch.nn as nn
from torch.utils.cpp_extension import load_inline
class ModelNew(nn.Module):
def __init__(self, in_features, alpha=0.0):
super().__init__()
self.alpha = nn.Parameter(torch.full((in_features,), alpha))
self._compile_cuda_kernel()
def _compile_cuda_kernel(self):
cpp_source = """
#include <torch/extension.h>
torch::Tensor soft_exponential_cuda(torch::Tensor x, torch::Tensor alpha);
"""
cuda_source = """
#include <cuda_runtime.h>
__device__ __forceinline__ float compute_se(float x, float a) {
if (fabsf(a) < 1e-6f) {
return x;
} else if (a > 0.0f) {
return (expf(a * x) - 1.0f) / a + a;
} else {
float val = 1.0f - a * (x + a);
return (val > 0.0f) ? (-logf(val) / a) : 0.0f;
}
}
__global__ void soft_exponential_vec4(
const float* __restrict__ x,
float* __restrict__ y,
const float* __restrict__ alpha,
int total_vecs,
int spatial_vecs,
int channels)
{
int idx = blockIdx.x * blockDim.x + threadIdx.x;
int stride = gridDim.x * blockDim.x;
const float4* x_vec = reinterpret_cast<const float4*>(x);
float4* y_vec = reinterpret_cast<float4*>(y);
for (int i = idx; i < total_vecs; i += stride) {
float4 v = x_vec[i];
float4 out;
int c = (i / spatial_vecs) % channels;
float a = alpha[c];
out.x = compute_se(v.x, a);
out.y = compute_se(v.y, a);
out.z = compute_se(v.z, a);
out.w = compute_se(v.w, a);
y_vec[i] = out;
}
}
__global__ void soft_exponential_scalar(
const float* __restrict__ x,
float* __restrict__ y,
const float* __restrict__ alpha,
int total_elements,
int spatial_size,
int channels)
{
int idx = blockIdx.x * blockDim.x + threadIdx.x;
int stride = gridDim.x * blockDim.x;
for (int i = idx; i < total_elements; i += stride) {
int c = (i / spatial_size) % channels;
float a = alpha[c];
y[i] = compute_se(x[i], a);
}
}
torch::Tensor soft_exponential_cuda(torch::Tensor x, torch::Tensor alpha) {
auto x_c = x.contiguous();
auto alpha_c = alpha.contiguous();
auto output = torch::empty_like(x_c);
int total_elements = x_c.numel();
int N = x_c.size(0);
int C = x_c.size(1);
int S = total_elements / (N * C);
if (S % 4 == 0) {
int total_vecs = total_elements / 4;
int spatial_vecs = S / 4;
int threads = 256;
int blocks = (total_vecs + threads - 1) / threads;
if (blocks > 65535) blocks = 65535;
soft_exponential_vec4<<<blocks, threads>>>(
x_c.data_ptr<float>(),
output.data_ptr<float>(),
alpha_c.data_ptr<float>(),
total_vecs,
spatial_vecs,
C
);
} else {
int threads = 256;
int blocks = (total_elements + threads - 1) / threads;
if (blocks > 65535) blocks = 65535;
soft_exponential_scalar<<<blocks, threads>>>(
x_c.data_ptr<float>(),
output.data_ptr<float>(),
alpha_c.data_ptr<float>(),
total_elements,
S,
C
);
}
return output;
}
"""
self.op = load_inline(
name="soft_exponential_opt",
cpp_sources=cpp_source,
cuda_sources=cuda_source,
functions=["soft_exponential_cuda"],
extra_cuda_cflags=["-O3"],
verbose=False
)
def forward(self, x):
return self.op.soft_exponential_cuda(x, self.alpha)