sandboxed-api/oss-internship-2020/pffft/main_pffft_sandboxed.cc
Christian Blichmann d451478e26 Change license link to HTTPS URL
PiperOrigin-RevId: 424811734
Change-Id: If5ea692edc56ddc9c99fd478673df41c0246e9cc
2022-01-28 01:39:09 -08:00

208 lines
6.5 KiB
C++

// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <gflags/gflags.h>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <glog/logging.h>
#include "pffft_sapi.sapi.h" // NOLINT(build/include)
#include "sandboxed_api/util/flag.h"
#include "sandboxed_api/vars.h"
ABSL_DECLARE_FLAG(string, sandbox2_danger_danger_permit_all);
ABSL_DECLARE_FLAG(string, sandbox2_danger_danger_permit_all_and_log);
class PffftSapiSandbox : public PffftSandbox {
public:
std::unique_ptr<sandbox2::Policy> ModifyPolicy(sandbox2::PolicyBuilder*) {
return sandbox2::PolicyBuilder()
.AllowStaticStartup()
.AllowOpen()
.AllowRead()
.AllowWrite()
.AllowSystemMalloc()
.AllowExit()
.AllowSyscalls({
__NR_futex,
__NR_close,
__NR_getrusage,
})
.BuildOrDie();
}
};
// output_format flag determines whether the output shows information in detail
// or not. By default, the flag is set as 0, meaning an elaborate display
// (see ShowOutput method).
static bool ValidateFlag(const char* flagname, int32_t value) {
if (value >= 0 && value < 32768) {
return true;
}
LOG(ERROR) << "Invalid value for --" << flagname << ".";
return false;
}
DEFINE_int32(output_format, 0, "Value to specific the output format.");
DEFINE_validator(output_format, &ValidateFlag);
double UclockSec() { return static_cast<double>(clock()) / CLOCKS_PER_SEC; }
void ShowOutput(const char* name, int n, int complex, float flops, float t0,
float t1, int max_iter) {
float mflops = flops / 1e6 / (t1 - t0 + 1e-16);
if (FLAGS_output_format) {
if (flops != -1) {
printf("|%9.0f ", mflops);
} else {
printf("| n/a ");
}
} else if (flops != -1) {
printf("n=%5d, %s %16s : %6.0f MFlops [t=%6.0f ns, %d runs]\n", n,
(complex ? "CPLX" : "REAL"), name, mflops,
(t1 - t0) / 2 / max_iter * 1e9, max_iter);
}
fflush(stdout);
}
absl::Status PffftMain() {
LOG(INFO) << "Initializing sandbox...\n";
PffftSapiSandbox sandbox;
SAPI_RETURN_IF_ERROR(sandbox.Init());
PffftApi api(&sandbox);
// kTransformSizes is a vector keeping the values by which iterates n, its
// value representing the input length. More concrete, n is the number of data
// points the caclulus is up to (determinating its accuracy). To show the
// performance of Fast-Fourier Transformations the program is testing for
// various values of n.
constexpr int kTransformSizes[] = {
64, 96, 128, 160, 192, 256, 384, 5 * 96, 512, 5 * 128,
3 * 256, 800, 1024, 2048, 2400, 4096, 8192, 9 * 1024, 16384, 32768};
for (int complex : {0, 1}) {
for (int n : kTransformSizes) {
const int n_float = n * (complex ? 2 : 1);
int n_bytes = n_float * sizeof(float);
std::vector<float> work(2 * n_float + 15, 0.0);
sapi::v::Array<float> work_array(&work[0], work.size());
std::vector<float> x(n_bytes, 0.0);
sapi::v::Array<float> x_array(&x[0], x.size());
std::vector<float> y(n_bytes, 0.0);
sapi::v::Array<float> y_array(&y[0], y.size());
std::vector<float> z(n_bytes, 0.0);
sapi::v::Array<float> z_array(&z[0], z.size());
double t0;
double t1;
double flops;
int max_iter = 5120000 / n * 4;
for (int k = 0; k < n_float; ++k) {
x[k] = 0;
}
// FFTPack benchmark
{
// SIMD_SZ == 4 (returning value of pffft_simd_size())
int simd_size_iter = max_iter / 4;
if (simd_size_iter == 0) simd_size_iter = 1;
if (complex) {
SAPI_RETURN_IF_ERROR(api.cffti(n, work_array.PtrBoth()))
} else {
SAPI_RETURN_IF_ERROR(api.rffti(n, work_array.PtrBoth()));
}
t0 = UclockSec();
for (int iter = 0; iter < simd_size_iter; ++iter) {
if (complex) {
SAPI_RETURN_IF_ERROR(
api.cfftf(n, x_array.PtrBoth(), work_array.PtrBoth()));
SAPI_RETURN_IF_ERROR(
api.cfftb(n, x_array.PtrBoth(), work_array.PtrBoth()));
} else {
SAPI_RETURN_IF_ERROR(
api.rfftf(n, x_array.PtrBoth(), work_array.PtrBoth()));
SAPI_RETURN_IF_ERROR(
api.rfftb(n, x_array.PtrBoth(), work_array.PtrBoth()));
}
}
t1 = UclockSec();
flops = (simd_size_iter * 2) *
((complex ? 5 : 2.5) * static_cast<double>(n) *
log(static_cast<double>(n)) / M_LN2);
ShowOutput("FFTPack", n, complex, flops, t0, t1, simd_size_iter);
}
// PFFFT benchmark
{
SAPI_ASSIGN_OR_RETURN(
PFFFT_Setup * s,
api.pffft_new_setup(n, complex ? PFFFT_COMPLEX : PFFFT_REAL));
sapi::v::RemotePtr s_reg(s);
t0 = UclockSec();
for (int iter = 0; iter < max_iter; ++iter) {
SAPI_RETURN_IF_ERROR(
api.pffft_transform(&s_reg, x_array.PtrBoth(), z_array.PtrBoth(),
y_array.PtrBoth(), PFFFT_FORWARD));
SAPI_RETURN_IF_ERROR(
api.pffft_transform(&s_reg, x_array.PtrBoth(), z_array.PtrBoth(),
y_array.PtrBoth(), PFFFT_FORWARD));
}
t1 = UclockSec();
SAPI_RETURN_IF_ERROR(api.pffft_destroy_setup(&s_reg));
flops = (max_iter * 2) * ((complex ? 5 : 2.5) * static_cast<double>(n) *
log(static_cast<double>(n)) / M_LN2);
ShowOutput("PFFFT", n, complex, flops, t0, t1, max_iter);
LOG(INFO) << "n = " << n << " SUCCESSFULLY";
}
}
}
return absl::OkStatus();
}
int main(int argc, char* argv[]) {
// Initialize Google's logging library.
google::InitGoogleLogging(argv[0]);
gflags::ParseCommandLineFlags(&argc, &argv, true);
if (absl::Status status = PffftMain(); !status.ok()) {
LOG(ERROR) << "Initialization failed: " << status.ToString();
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}