X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/ba6e6b64033b1f9de49feccb5c9cd438354481f7..0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a:/math/bitops.h

diff --git a/math/bitops.h b/math/bitops.h
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+/* -*-c-*-
+ *
+ * Bit operations by truth table
+ *
+ * (c) 2002 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#ifndef CATACOMB_BITOPS_H
+#define CATACOMB_BITOPS_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+/*----- Macros ------------------------------------------------------------*/
+
+#define B0000(x, y) (0u)
+#define B0001(x, y) ((x) & (y))
+#define B0010(x, y) ((x) & ~(y))
+#define B0011(x, y) (x)
+#define B0100(x, y) (~(x) & (y))
+#define B0101(x, y) (y)
+#define B0110(x, y) ((x) ^ (y))
+#define B0111(x, y) ((x) | (y))
+#define B1000(x, y) (~((x) | (y)))
+#define B1001(x, y) (~((x) ^ (y)))
+#define B1010(x, y) (~(y))
+#define B1011(x, y) ((x) | ~(y))
+#define B1100(x, y) (~(x))
+#define B1101(x, y) (~(x) | (y))
+#define B1110(x, y) (~((x) & (y)))
+#define B1111(x, y) (~0u)
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif