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#include <stdio.h>
#include <stdint.h>
#include <sat_arith/sat_arith.h>
static int64_t formal_sat_mul(int64_t i, int64_t j, int64_t min, int64_t max)
{
int64_t result = i * j;
if (result < min)
result = min;
if (result > max)
result = max;
return result;
}
static int test_i8()
{
for (int64_t i = INT8_MIN; i <= INT8_MAX; ++i)
for (int64_t j = INT8_MIN; j <= INT8_MAX; ++j) {
int64_t expected = formal_sat_mul(i, j, INT8_MIN, INT8_MAX);
int8_t got = mul_sat((int8_t)i, (int8_t)j);
if (expected != got) {
printf("%lld * %lld should be %lld, but got %lld!\n",
(long long)i,
(long long)j,
(long long)expected,
(long long)got);
return -1;
}
}
return 0;
}
static int test_i16()
{
for (int64_t i = INT16_MIN; i <= INT16_MAX; ++i)
for (int64_t j = INT16_MIN; j <= INT16_MAX; ++j) {
int64_t expected = formal_sat_mul(i, j, INT16_MIN, INT16_MAX);
int16_t got = mul_sat((int16_t)i, (int16_t)j);
if (expected != got) {
printf("%lld * %lld should be %lld, but got %lld!\n",
(long long)i,
(long long)j,
(long long)expected,
(long long)got);
return -1;
}
}
return 0;
}
static int test_u16()
{
for (int64_t i = 0; i <= UINT16_MAX; ++i)
for (int64_t j = 0; j <= UINT16_MAX; ++j) {
int64_t expected = formal_sat_mul(i, j, 0, UINT16_MAX);
uint16_t got = mul_sat((uint16_t)i, (uint16_t)j);
if (expected != got) {
printf("%lld * %lld should be %lld, but got %lld!\n",
(long long)i,
(long long)j,
(long long)expected,
(long long)got);
return -1;
}
}
return 0;
}
static int test_u8()
{
for (int64_t i = 0; i <= UINT8_MAX; ++i)
for (int64_t j = 0; j <= UINT8_MAX; ++j) {
int64_t expected = formal_sat_mul(i, j, 0, UINT8_MAX);
uint8_t got = mul_sat((uint8_t)i, (uint8_t)j);
if (expected != got) {
printf("%lld * %lld should be %lld, but got %lld!\n",
(long long)i,
(long long)j,
(long long)expected,
(long long)got);
return -1;
}
}
return 0;
}
int main()
{
printf("mul_sat\n");
/* these are still relatively easy to exhaustively check */
printf("i8...\n");
if (test_i8()) {
printf("FAIL!\n");
return -1;
}
printf("u8...\n");
if (test_u8()) {
printf("FAIL!\n");
return -1;
}
printf("i16...\n");
if (test_i16()) {
printf("FAIL!\n");
return -1;
}
printf("u16...\n");
if (test_u16()) {
printf("FAIL!\n");
return -1;
}
/* might add some random testing for 32/64 bit values, but presumably if
* the narrower types work, the wider ones should work as well (assuming
* I don't have some any silly typos or something) */
printf("OK!\n");
return 0;
}
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