initHEADmaster

1 files changed, 128 insertions, 0 deletions

diff --git a/tests/sub_sat.c b/tests/sub_sat.c
new file mode 100644
index 0000000..226362c
--- /dev/null
+++ b/tests/sub_sat.c
@@ -0,0 +1,128 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <sat_arith/sat_arith.h>
+
+static int64_t formal_sat_sub(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_sub(i, j, INT8_MIN, INT8_MAX);
+		int8_t got = sub_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_sub(i, j, INT16_MIN, INT16_MAX);
+		int16_t got = sub_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_sub(i, j, 0, UINT16_MAX);
+		uint16_t got = sub_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_sub(i, j, 0, UINT8_MAX);
+		uint8_t got = sub_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("sub_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;
+}