blob: a7a65145d8d7cdcde5b17203c32eabd92c2b902a [file] [log] [blame]
// Copyright 2023 Google LLC
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
//
// Use the routine of finding the integer part of log_3 to stress test
// branch/div op combinations.
#include <stdint.h>
#include <stdlib.h>
#include "crt/kelvin.h"
template <typename T>
T get_int_log3(T a) {
T int_log3 = 0;
if (a < 3) return 0;
// Use do/while loop to compile the code without jump
do {
int_log3++;
a /= 3;
} while (a >= 3);
return int_log3;
}
template <typename T>
T int_pow3(T a) {
T result = 1;
for (T i = 0; i < a; ++i) {
result *= 3;
}
return result;
}
uint32_t rand_uint32_input() {
uint32_t a = static_cast<uint32_t>(
((rand() & 0xffff) << 16) | // NOLINT(runtime/threadsafe_fn)
(rand() & 0xffff)); // NOLINT(runtime/threadsafe_fn)
return std::max<uint32_t>(a, 1);
}
int32_t rand_int32_input() {
int32_t a = ((rand() & 0x7fff) << 16) | // NOLINT(runtime/threadsafe_fn)
(rand() & 0xffff); // NOLINT(runtime/threadsafe_fn)
return std::max<int32_t>(a, 1);
}
int main() {
constexpr int kSeed = 1000;
srand(kSeed);
uint32_t uint32_input = rand_uint32_input();
int32_t int32_input = rand_int32_input();
auto uint32_log3 = get_int_log3<uint32_t>(uint32_input);
printf("Unsigned input: %u, integer log3: %u\n", uint32_input, uint32_log3);
auto test = int_pow3<uint32_t>(uint32_log3);
// Make the check like this to prevent overflow
if (!(test <= uint32_input && test >= uint32_input / 3)) {
printf("Invalid log_3 %u for %u\n", uint32_log3, uint32_input);
exit(-1);
}
auto int32_log3 = get_int_log3<int32_t>(int32_input);
printf("Signed intput:%d, integer log3: %d\n", int32_input, int32_log3);
auto test1 = int_pow3<int32_t>(int32_log3);
if (!(test1 <= int32_input && test1 >= int32_input / 3)) {
printf("Invalid log_3 %d for %d\n", int32_log3, int32_input);
exit(-1);
}
return 0;
}