12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485 |
- // Copyright 2019 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
- #include <algorithm>
- #include <array>
- #include <cassert>
- #include <cstring>
- #include "third_party/pffft/src/pffft.h"
- namespace {
- #if defined(TRANSFORM_REAL)
- // Real FFT.
- constexpr pffft_transform_t kTransform = PFFFT_REAL;
- constexpr size_t kSizeOfOneSample = sizeof(float);
- #elif defined(TRANSFORM_COMPLEX)
- // Complex FFT.
- constexpr pffft_transform_t kTransform = PFFFT_COMPLEX;
- constexpr size_t kSizeOfOneSample = 2 * sizeof(float); // Real plus imaginary.
- #else
- #error FFT transform type not defined.
- #endif
- bool IsValidSize(size_t n) {
- if (n == 0) {
- return false;
- }
- // PFFFT only supports transforms for inputs of length N of the form
- // N = (2^a)*(3^b)*(5^c) where a >= 5, b >=0, c >= 0.
- constexpr std::array<int, 3> kFactors = {2, 3, 5};
- std::array<int, kFactors.size()> factorization{};
- for (size_t i = 0; i < kFactors.size(); ++i) {
- const int factor = kFactors[i];
- while (n % factor == 0) {
- n /= factor;
- factorization[i]++;
- }
- }
- return factorization[0] >= 5 && n == 1;
- }
- float* AllocatePffftBuffer(size_t number_of_bytes) {
- return static_cast<float*>(pffft_aligned_malloc(number_of_bytes));
- }
- } // namespace
- // Entry point for LibFuzzer.
- extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
- // Set the number of FFT points to use |data| as input vector.
- // The latter is truncated if the number of bytes is not an integer
- // multiple of the size of one sample (which is either a real or a complex
- // floating point number).
- const size_t fft_size = size / kSizeOfOneSample;
- if (!IsValidSize(fft_size)) {
- return 0;
- }
- const size_t number_of_bytes = fft_size * kSizeOfOneSample;
- assert(number_of_bytes <= size);
- // Allocate input and output buffers.
- float* in = AllocatePffftBuffer(number_of_bytes);
- float* out = AllocatePffftBuffer(number_of_bytes);
- // Copy input data.
- std::memcpy(in, reinterpret_cast<const float*>(data), number_of_bytes);
- // Setup FFT.
- PFFFT_Setup* pffft_setup = pffft_new_setup(fft_size, kTransform);
- // Call different PFFFT functions to maximize the coverage.
- pffft_transform(pffft_setup, in, out, nullptr, PFFFT_FORWARD);
- pffft_zconvolve_accumulate(pffft_setup, out, out, out, 1.f);
- pffft_transform_ordered(pffft_setup, in, out, nullptr, PFFFT_BACKWARD);
- // Release memory.
- pffft_aligned_free(in);
- pffft_aligned_free(out);
- pffft_destroy_setup(pffft_setup);
- return 0;
- }
|