GPUCodeForces/S1/uucoco_#70/robustscalegate_cuda.py

112 lines
3.4 KiB
Python

import torch
import torch.nn as nn
from torch.utils.cpp_extension import load_inline
class ModelNew(nn.Module):
def __init__(self):
super().__init__()
self._compile_cuda_kernel()
self.epsilon = 1e-5
def _compile_cuda_kernel(self):
cpp_source = """
torch::Tensor rsg_apply_cuda(torch::Tensor x, torch::Tensor x_flat_sorted, float epsilon);
"""
cuda_source = """
#include <torch/extension.h>
#include <cuda_runtime.h>
#include <math.h>
__device__ __forceinline__ float sigmoid_op(float x) {
if (x >= 0.0f) {
return 1.0f / (1.0f + expf(-x));
} else {
float z = expf(x);
return z / (1.0f + z);
}
}
__global__ void rsg_apply_kernel(
const float* __restrict__ x,
float* __restrict__ output,
const int n_elements,
const float median_val,
const float iqr_recip)
{
const int tid = blockIdx.x * blockDim.x + threadIdx.x;
const int stride = blockDim.x * gridDim.x;
for (int i = tid; i < n_elements; i += stride) {
float val = x[i];
float z_robust = (val - median_val) * iqr_recip;
float gate = sigmoid_op(val);
output[i] = z_robust * gate;
}
}
torch::Tensor rsg_apply_cuda(torch::Tensor x, torch::Tensor x_flat_sorted, float epsilon) {
auto x_c = x.contiguous();
const int n_elements = x_c.numel();
int n = x_flat_sorted.size(0);
float median_val, q1_val, q3_val;
int median_idx = n / 2;
int q1_idx = n / 4;
int q3_idx = (3 * n) / 4;
if (n % 2 == 0) {
median_val = (x_flat_sorted[median_idx - 1].item<float>() + x_flat_sorted[median_idx].item<float>()) * 0.5f;
} else {
median_val = x_flat_sorted[median_idx].item<float>();
}
if (n % 4 == 0) {
q1_val = (x_flat_sorted[q1_idx - 1].item<float>() + x_flat_sorted[q1_idx].item<float>()) * 0.5f;
} else {
q1_val = x_flat_sorted[q1_idx].item<float>();
}
if ((3 * n) % 4 == 0) {
q3_val = (x_flat_sorted[q3_idx - 1].item<float>() + x_flat_sorted[q3_idx].item<float>()) * 0.5f;
} else {
q3_val = x_flat_sorted[q3_idx].item<float>();
}
float iqr = q3_val - q1_val;
float iqr_recip = 1.0f / (iqr + epsilon);
auto output = torch::empty_like(x_c);
const int threads = 256;
const int blocks = min((n_elements + threads - 1) / threads, 65535);
rsg_apply_kernel<<<blocks, threads>>>(
x_c.data_ptr<float>(),
output.data_ptr<float>(),
n_elements,
median_val,
iqr_recip
);
return output;
}
"""
self.op = load_inline(
name="rsg_v4",
cpp_sources=cpp_source,
cuda_sources=cuda_source,
functions=["rsg_apply_cuda"],
extra_cuda_cflags=["-O3"],
verbose=False
)
def forward(self, x):
x_flat = x.flatten()
x_flat_sorted = x_flat.sort()[0]
return self.op.rsg_apply_cuda(x, x_flat_sorted, self.epsilon)