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authorMattias Andrée <m@maandree.se>2025-12-04 19:25:47 +0100
committerMattias Andrée <m@maandree.se>2025-12-04 19:25:47 +0100
commit2bf851de6dd3a64f91a72a9afba2b3637dbbe154 (patch)
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First commit
Signed-off-by: Mattias Andrée <m@maandree.se>
Diffstat (limited to '')
-rw-r--r--libj2_j2u_lrot.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/libj2_j2u_lrot.c b/libj2_j2u_lrot.c
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+++ b/libj2_j2u_lrot.c
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+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+extern inline void libj2_j2u_lrot(struct libj2_j2u *a, unsigned b);
+/* TODO Add man page */
+
+
+#else
+
+static void
+set(struct libj2_j2u *a, const char *pattern, unsigned shift)
+{
+ unsigned i, j = (LIBJ2_J2U_BIT - (shift % LIBJ2_J2U_BIT)) % LIBJ2_J2U_BIT;
+
+ a->high = 0;
+ a->low = 0;
+
+ for (i = 0; i < LIBJ2_JU_BIT; i++, j++)
+ if (pattern[j % LIBJ2_J2U_BIT] == '1')
+ a->low |= (uintmax_t)1 << i;
+
+ for (i = 0; i < LIBJ2_JU_BIT; i++, j++)
+ if (pattern[j % LIBJ2_J2U_BIT] == '1')
+ a->high |= (uintmax_t)1 << i;
+
+}
+
+
+int
+main(void)
+{
+ struct libj2_j2u a, r, a_saved, expected;
+ char pattern[LIBJ2_J2U_BIT + 1U];
+ unsigned i, j, k;
+
+ srand((unsigned)time(NULL));
+
+ for (i = 0; i < 128U; i++) {
+ for (j = 0; j < LIBJ2_J2U_BIT; j++)
+ pattern[j] = '0' + (rand() < rand());
+ pattern[LIBJ2_J2U_BIT] = '\0';
+ set(&a, pattern, 0);
+ a_saved = a;
+ for (j = 0; j <= 2U * LIBJ2_J2U_BIT; j++) {
+ set(&expected, pattern, j);
+
+ r = a;
+ libj2_j2u_lrot(&r, j);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+
+ r = (struct libj2_j2u){111, 222};
+ libj2_j2u_lrot_to_j2u(&a, j, &r);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+ EXPECT(libj2_j2u_eq_j2u(&a, &a_saved));
+
+ r = a;
+ libj2_j2u_lrot_to_j2u(&r, j, &r);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+
+ k = 2U * LIBJ2_J2U_BIT - j;
+
+ r = a;
+ libj2_j2u_rrot(&r, k);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+
+ r = (struct libj2_j2u){111, 222};
+ libj2_j2u_rrot_to_j2u(&a, k, &r);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+ EXPECT(libj2_j2u_eq_j2u(&a, &a_saved));
+
+ r = a;
+ libj2_j2u_rrot_to_j2u(&r, k, &r);
+ EXPECT(libj2_j2u_eq_j2u(&r, &expected));
+ }
+ }
+
+ return 0;
+}
+
+#endif