First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 166 insertions, 0 deletions

diff --git a/libnormalform_imply.c b/libnormalform_imply.c
new file mode 100644
index 0000000..823abf7
--- /dev/null
+++ b/libnormalform_imply.c
@@ -0,0 +1,166 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+LIBNORMALFORM_SENTENCE *
+(libnormalform_imply)(LIBNORMALFORM_SENTENCE **xs)
+{
+	LIBNORMALFORM_SENTENCE *t;
+	size_t n = 0, i;
+
+	while (xs[n])
+		n += 1;
+
+	if (!n) {
+		/* 1 → x = x and 0 → x = 1 */
+		return libnormalform_true();
+	}
+
+	/* a → b → c = a → (b → c) = (b → c) ← a = (c ← b) ← a = c ← b ← a */
+	for (i = 0; i < n--; i++) {
+		t = xs[i];
+		xs[i] = xs[n];
+		xs[n] = t;
+	}
+	return libnormalform_if(xs);
+}
+
+
+#else
+
+
+#define IMPLY(...) LIBNORMALFORM_IMPLY(__VA_ARGS__)
+
+
+int
+main(void)
+{
+	struct libnormalform_variable var1, var2, var3;
+	LIBNORMALFORM_SENTENCE *a, *b, *v1, *v2, *v3;
+	LIBNORMALFORM_SENTENCE *ts, *fs;
+
+	ASSUME(v1 = libnormalform_variable(&var1));
+	ASSUME(v2 = libnormalform_variable(&var2));
+	ASSUME(v3 = libnormalform_variable(&var3));
+	ASSUME(ts = libnormalform_true());
+	ASSUME(fs = libnormalform_false());
+
+#ifdef USE_CHECKED_VERSION
+	errno = 0;
+	ASSERT(!IMPLY(REF(v1), NULL) && errno == 0);
+	errno = 1;
+	ASSERT(!IMPLY(REF(v1), NULL) && errno == 1);
+	errno = 0;
+	ASSERT(!IMPLY(NULL, REF(v1)) && errno == 0);
+	errno = 1;
+	ASSERT(!IMPLY(NULL, REF(v1)) && errno == 1);
+	errno = 0;
+	ASSERT(!IMPLY(NULL, NULL) && errno == 0);
+	errno = 1;
+	ASSERT(!IMPLY(NULL, NULL) && errno == 1);
+#endif
+
+#define T REF(ts)
+#define F REF(fs)
+#define TV LIBNORMALFORM_TRUE
+#define FV LIBNORMALFORM_FALSE
+
+#define ASSERT_CONST(VALUE, ...)\
+	do {\
+		ASSUME(a = IMPLY(__VA_ARGS__));\
+		ASSERT(a->type == TYPE_##VALUE);\
+		libnormalform_free(a);\
+	} while (0)
+
+#define ASSERT_EVAL2(VALUE, V1, V2)\
+	do {\
+		ASSUME(a = IMPLY(REF(v1), REF(v2)));\
+		ASSERT(a->type != TYPE_TRUE && a->type != TYPE_FALSE);\
+		var1.value = V1##V;\
+		var2.value = V2##V;\
+		ASSERT(libnormalform_evaluate(a) == (int)LIBNORMALFORM_##VALUE);\
+		libnormalform_free(a);\
+	} while (0)
+
+#ifndef USE_TWO
+
+#if defined(__GNUC__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wformat"
+#endif
+
+	ASSERT_CONST(TRUE); /* IMPLY () -> TRUE */
+
+#if defined(__GNUC__)
+# pragma GCC diagnostic pop
+#endif
+
+	ASSERT_CONST(TRUE, T);  /* IMPLY (TRUE) -> TRUE */
+	ASSERT_CONST(FALSE, F); /* IMPLY (FALSE) -> FALSE */
+
+#endif
+
+	ASSERT_CONST(TRUE,  F, F); /* IMPLY (FALSE, FALSE) -> TRUE */
+	ASSERT_CONST(TRUE,  F, T); /* IMPLY (FALSE, TRUE) -> TRUE */
+	ASSERT_CONST(FALSE, T, F); /* IMPLY (TRUE, FALSE) -> FALSE */
+	ASSERT_CONST(TRUE,  T, T); /* IMPLY (TRUE, TRUE) -> TRUE */
+
+	ASSERT_EVAL2(TRUE,  F, F); /* IMPLY (var(FALSE), var(FALSE)) => TRUE */
+	ASSERT_EVAL2(TRUE,  F, T); /* IMPLY (var(FALSE), var(TRUE)) => TRUE */
+	ASSERT_EVAL2(FALSE, T, F); /* IMPLY (var(TRUE), var(FALSE)) => FALSE */
+	ASSERT_EVAL2(TRUE,  T, T); /* IMPLY (var(TRUE), var(TRUE)) => TRUE */
+
+#ifndef USE_TWO
+
+	/* IMPLY (x) -> x */
+	ASSUME(a = IMPLY(REF(v1)));
+	ASSERT(a == v1);
+	ASSERT(a->refcount == 2);
+	libnormalform_free(a);
+
+#endif
+
+	/* IMPLY (x, y) -> IF (y, x) */
+	ASSUME(a = IMPLY(REF(v1), REF(v2)));
+	ASSUME(b = libnormalform_if2(REF(v2), REF(v1)));
+	ASSERT_EQUAL(a, b);
+	libnormalform_free(a);
+	libnormalform_free(b);
+
+#ifndef USE_TWO
+
+	/* IMPLY (x, y, z) -> IF (z, y, x) */
+	ASSUME(a = IMPLY(REF(v1), REF(v2), REF(v3)));
+	ASSUME(b = libnormalform_ifl(REF(v3), REF(v2), REF(v1), NULL));
+	ASSERT_EQUAL(a, b);
+	libnormalform_free(a);
+	libnormalform_free(b);
+
+	/* IMPLY (x, y) -> independence from IMPLY (y, x) */
+	ASSUME(a = IMPLY(REF(v1), REF(v2)));
+	ASSUME(b = IMPLY(REF(v2), REF(v1)));
+	ASSERT_NOTEQUAL(a, b);
+	libnormalform_free(a);
+	libnormalform_free(b);
+
+#endif
+
+#undef T
+#undef F
+#undef TV
+#undef FV
+
+#undef ASSERT_CONST
+#undef ASSERT_EVAL2
+
+	libnormalform_free(v1);
+	libnormalform_free(v2);
+	libnormalform_free(v3);
+	libnormalform_free(ts);
+	libnormalform_free(fs);
+	return 0;
+}
+
+
+#endif