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-rw-r--r--libj2_j2i_add_j2i.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/libj2_j2i_add_j2i.c b/libj2_j2i_add_j2i.c
new file mode 100644
index 0000000..f1889d8
--- /dev/null
+++ b/libj2_j2i_add_j2i.c
@@ -0,0 +1,341 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+extern inline void libj2_j2i_add_j2i(struct libj2_j2i *a, const struct libj2_j2i *b);
+/* TODO Add man page */
+
+
+#else
+
+static uintmax_t
+random_ju(void)
+{
+ size_t n = LIBJ2_JU_BIT;
+ uintmax_t r = 0;
+ while (n--)
+ if (rand() < rand())
+ r |= (uintmax_t)1 << n;
+ return r;
+}
+
+
+static void
+check_(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low,
+ uintmax_t r_high, uintmax_t r_low, int r_overflow)
+{
+ struct libj2_j2i a, b, r, a_saved, b_saved, expected;
+
+ a_saved = (struct libj2_j2i){.high = a_high, .low = a_low};
+ b_saved = (struct libj2_j2i){.high = b_high, .low = b_low};
+ expected = (struct libj2_j2i){.high = r_high, .low = r_low};
+
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_add_j2i(&a, &b);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_add_j2i_to_j2i(&a, &b, &r);
+ EXPECT(libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_add_j2i_to_j2i(&a, &b, &a);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_add_j2i_to_j2i(&a, &b, &b);
+ EXPECT(libj2_j2i_eq_j2i(&b, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+ a = a_saved;
+ b = b_saved;
+ EXPECT(libj2_j2i_add_j2i_overflow(&a, &b) == r_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+#if 0 /* TODO saturated addition */
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_sat_add_j2i(&a, &b);
+ EXPECT(r_overflow ? libj2_j2i_is_max(&a) : libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+#endif
+
+ a = a_saved;
+ b = b_saved;
+ EXPECT(libj2_j2i_add_j2i_overflow_p((const struct libj2_j2i *)&a, (const struct libj2_j2i *)&b) == r_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ b = b_saved;
+ EXPECT(libj2_j2i_add_j2i_to_j2i_overflow(&a, &b, &r) == r_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ EXPECT(libj2_j2i_add_j2i_to_j2i_overflow(&a, &b, &a) == r_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ EXPECT(libj2_j2i_add_j2i_to_j2i_overflow(&a, &b, &b) == r_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&b, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+#if 0 /* TODO saturated addition */
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_sat_add_j2i_to_j2i(&a, &b, &r);
+ EXPECT(r_overflow ? libj2_j2i_is_max(&r) : libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_sat_add_j2i_to_j2i(&a, &b, &a);
+ EXPECT(r_overflow ? libj2_j2i_is_max(&a) : libj2_j2i_eq_j2i(&a, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&b, &b_saved));
+
+ a = a_saved;
+ b = b_saved;
+ libj2_j2i_sat_add_j2i_to_j2i(&a, &b, &b);
+ EXPECT(r_overflow ? libj2_j2i_is_max(&b) : libj2_j2i_eq_j2i(&b, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+#endif
+}
+
+
+static void
+check(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low)
+{
+ uintmax_t a_neg = a_high >> (LIBJ2_JU_BIT - 1U);
+ uintmax_t b_neg = b_high >> (LIBJ2_JU_BIT - 1U);
+ uintmax_t r_high = 0, r_low = 0, carry = 0;
+ int r_overflow = 0;
+ unsigned i;
+
+ for (i = 0; i < LIBJ2_JU_BIT; i++) {
+ carry += (a_low >> i) & 1U;
+ carry += (b_low >> i) & 1U;
+ r_low |= (carry & 1U) << i;
+ carry >>= 1;
+ }
+
+ for (i = 0; i < LIBJ2_JU_BIT - 1U; i++) {
+ carry += (a_high >> i) & 1U;
+ carry += (b_high >> i) & 1U;
+ r_high |= (carry & 1U) << i;
+ carry >>= 1;
+ }
+
+ carry += (a_high >> i) & 1U;
+ carry += (b_high >> i) & 1U;
+ r_high |= (carry & 1U) << i;
+ carry >>= 1;
+
+ if (a_neg)
+ carry ^= 1U;
+
+ if (a_neg ^ b_neg)
+ r_overflow = 0;
+ else if (a_neg)
+ r_overflow = -!(r_high >> (LIBJ2_JU_BIT - 1U));
+ else
+ r_overflow = !!(r_high >> (LIBJ2_JU_BIT - 1U));
+
+ check_(a_high, a_low, b_high, b_low, r_high, r_low, r_overflow);
+}
+
+
+static void
+check_manual(uintmax_t a_high, uintmax_t a_low, uintmax_t b_high, uintmax_t b_low,
+ uintmax_t r_high, uintmax_t r_low, int r_overflow)
+{
+ check_(a_high, a_low, b_high, b_low, r_high, r_low, r_overflow);
+ check(a_high, a_low, b_high, b_low);
+}
+
+
+static void
+check_double(uintmax_t high, uintmax_t low)
+{
+ struct libj2_j2i a, r, a_saved, expected, b;
+ uintmax_t expected_high = (high << 1 | low >> (LIBJ2_JU_BIT - 1U));
+ uintmax_t expected_low = low << 1;
+ int expected_overflow = (int)(high >> (LIBJ2_JU_BIT - 2U));
+
+ expected_overflow ^= expected_overflow >> 1;
+ expected_overflow &= 1;
+
+ if (high >> (LIBJ2_JU_BIT - 1U))
+ expected_overflow = -expected_overflow;
+
+ a_saved = (struct libj2_j2i){.high = high, .low = low};
+ expected = (struct libj2_j2i){.high = expected_high, .low = expected_low};
+
+ a = a_saved;
+ b = a_saved;
+ libj2_j2i_add_j2i(&a, &b);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+
+ a = a_saved;
+ libj2_j2i_add_j2i(&a, &a);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ libj2_j2i_add_j2i_to_j2i(&a, &a, &r);
+ EXPECT(libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+ a = a_saved;
+ libj2_j2i_add_j2i_to_j2i(&a, &a, &a);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+
+ a = a_saved;
+ EXPECT(libj2_j2i_add_j2i_overflow(&a, &a) == expected_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+
+#if 0 /* TODO saturated addition */
+ a = a_saved;
+ libj2_j2i_sat_add_j2i(&a, &a);
+ EXPECT(expected_overflow ? libj2_j2i_is_max(&a) : libj2_j2i_eq_j2i(&a, &expected));
+#endif
+
+ a = a_saved;
+ EXPECT(libj2_j2i_add_j2i_overflow_p((const struct libj2_j2i *)&a, (const struct libj2_j2i *)&a) == expected_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ EXPECT(libj2_j2i_add_j2i_to_j2i_overflow(&a, &a, &r) == expected_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+ a = a_saved;
+ EXPECT(libj2_j2i_add_j2i_to_j2i_overflow(&a, &a, &a) == expected_overflow);
+ EXPECT(libj2_j2i_eq_j2i(&a, &expected));
+
+#if 0 /* TODO saturated addition */
+ r = (struct libj2_j2i){111, 222};
+ a = a_saved;
+ libj2_j2i_sat_add_j2i_to_j2i(&a, &a, &r);
+ EXPECT(expected_overflow ? libj2_j2i_is_max(&r) : libj2_j2i_eq_j2i(&r, &expected));
+ EXPECT(libj2_j2i_eq_j2i(&a, &a_saved));
+
+ a = a_saved;
+ libj2_j2i_sat_add_j2i_to_j2i(&a, &a, &a);
+ EXPECT(expected_overflow ? libj2_j2i_is_max(&a) : libj2_j2i_eq_j2i(&a, &expected));
+#endif
+}
+
+
+int
+main(void)
+{
+ uintmax_t a, b, c, d, max, min, umax, vs[12];
+ unsigned i, ii, ij, jj, k;
+
+ srand((unsigned)time(NULL));
+
+ umax = UINTMAX_MAX;
+ max = umax >> 1;
+ min = ~max;
+
+ vs[0] = 0U;
+ vs[1] = 1U;
+ vs[2] = 2U;
+ vs[3] = umax - 0U;
+ vs[4] = umax - 1U;
+ vs[5] = umax - 2U;
+ vs[6] = max - 0U;
+ vs[7] = max - 1U;
+ vs[8] = max - 2U;
+ vs[9] = min + 0U;
+ vs[10] = min + 1U;
+ vs[11] = min + 2U;
+
+ check_manual(0, 0, 0, 0, 0, 0, 0);
+ check_manual(0, 1, 0, 1, 0, 2, 0);
+ check_manual(0, UINTMAX_MAX, 0, 1, 1, 0, 0);
+ check_manual(0, UINTMAX_MAX, 0, UINTMAX_MAX, 1, UINTMAX_MAX - 1U, 0);
+ check_manual(UINTMAX_MAX >> 1, UINTMAX_MAX, UINTMAX_MAX >> 1, UINTMAX_MAX, UINTMAX_MAX, UINTMAX_MAX - 1U, +1);
+ check_manual((UINTMAX_MAX >> 1) + 1U, 0, (UINTMAX_MAX >> 1) + 1U, 0, 0, 0, -1);
+
+ for (i = 0; i < 256; i++)
+ check(random_ju() >> 1, random_ju(), random_ju() >> 1, random_ju());
+
+ check_double(0, 0);
+ check_double(0, UINTMAX_MAX);
+ check_double(UINTMAX_MAX, UINTMAX_MAX);
+ check_double(UINTMAX_MAX, 0);
+ check_double(UINTMAX_MAX >> 1, 0);
+ check_double(UINTMAX_MAX >> 1, UINTMAX_MAX);
+ check_double((UINTMAX_MAX >> 1) + 1U, 0);
+ for (i = 0; i < 256; i++) {
+ check_double(0, random_ju());
+ check_double(random_ju(), 0);
+ check_double(random_ju(), UINTMAX_MAX);
+ check_double(random_ju(), random_ju());
+ check_double(UINTMAX_MAX >> 1, random_ju());
+ check_double(UINTMAX_MAX, random_ju());
+ check_double((UINTMAX_MAX >> 1) + 1U, random_ju());
+ }
+
+ check_manual((UINTMAX_MAX >> 1) - 1U, UINTMAX_MAX - 1U, 1, 1, UINTMAX_MAX >> 1, UINTMAX_MAX, 0);
+ check_manual((UINTMAX_MAX >> 1) - 1U, UINTMAX_MAX - 1U, 1, 2, ~(uintmax_t)INTMAX_MAX, 0, 1);
+ check_manual((UINTMAX_MAX >> 1) - 1U, UINTMAX_MAX - 1U, 1, 3, ~(uintmax_t)INTMAX_MAX, 1, 1);
+
+ for (k = 0; k < 16U; k++) {
+ a = random_ju() >> 1;
+ b = random_ju() >> 1;
+ c = random_ju() >> 1;
+ d = random_ju() >> 1;
+ if (k & 1U) a = ~a;
+ if (k & 2U) b = ~b;
+ if (k & 4U) c = ~c;
+ if (k & 8U) d = ~d;
+ check(a, b, c, d);
+ for (i = 0; k < 8U && i < 12U; i++) {
+ check(a, b, c, vs[i]);
+ check(a, b, vs[i], c);
+ check(a, vs[i], b, c);
+ check(vs[i], a, b, c);
+ for (ii = 0; k < 4U && ii < 12U; ii++) {
+ check(a, b, vs[i], vs[ii]);
+ check(a, vs[i], b, vs[ii]);
+ check(a, vs[i], vs[ii], b);
+ check(vs[i], a, b, vs[ii]);
+ check(vs[i], a, vs[ii], b);
+ check(vs[i], vs[ii], a, b);
+ for (ij = 0; k < 2U && ij < 12U; ij++) {
+ check(vs[i], vs[ii], vs[ij], a);
+ check(vs[i], vs[ii], a, vs[ij]);
+ check(vs[i], a, vs[ii], vs[ij]);
+ check(a, vs[i], vs[ii], vs[ij]);
+ for (jj = 0; k < 1U && jj < 12U; jj++)
+ check(vs[i], vs[ii], vs[ij], vs[jj]);
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+#endif
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