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

diff --git a/math/karatsuba.h b/math/karatsuba.h
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+/* -*-c-*-
+ *
+ * Macros for Karatsuba functions
+ *
+ * (c) 2000 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_KARATSUBA_H
+#define CATACOMB_KARATSUBA_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+/*----- Header files ------------------------------------------------------*/
+
+#ifndef CATACOMB_MPW_H
+#  include "mpw.h"
+#endif
+
+/*----- Normal arithmetic macros ------------------------------------------*/
+
+#define UADD(dv, av, avl) do {						\
+  mpw *_dv = (dv);							\
+  const mpw *_av = (av), *_avl = (avl);					\
+  mpw _c = 0;								\
+									\
+  while (_av < _avl) {							\
+    mpw _a, _b;								\
+    mpd _x;								\
+    _a = *_av++;							\
+    _b = *_dv;								\
+    _x = (mpd)_a + (mpd)_b + _c;					\
+    *_dv++ = MPW(_x);							\
+    _c = _x >> MPW_BITS;						\
+  }									\
+  while (_c) {								\
+    mpd _x = (mpd)*_dv + (mpd)_c;					\
+    *_dv++ = MPW(_x);							\
+    _c = _x >> MPW_BITS;						\
+  }									\
+} while (0)
+
+#define UADD2(dv, dvl, av, avl, bv, bvl) do {				\
+  mpw *_dv = (dv), *_dvl = (dvl);					\
+  const mpw *_av = (av), *_avl = (avl);					\
+  const mpw *_bv = (bv), *_bvl = (bvl);					\
+  mpw _c = 0;								\
+									\
+  while (_av < _avl || _bv < _bvl) {					\
+    mpw _a, _b;								\
+    mpd _x;								\
+    _a = (_av < _avl) ? *_av++ : 0;					\
+    _b = (_bv < _bvl) ? *_bv++ : 0;					\
+    _x = (mpd)_a + (mpd)_b + _c;					\
+    *_dv++ = MPW(_x);							\
+    _c = _x >> MPW_BITS;						\
+  }									\
+  *_dv++ = _c;								\
+  while (_dv < _dvl)							\
+    *_dv++ = 0;								\
+} while (0)
+
+#define USUB(dv, av, avl) do {						\
+  mpw *_dv = (dv);							\
+  const mpw *_av = (av), *_avl = (avl);					\
+  mpw _c = 0;								\
+									\
+  while (_av < _avl) {							\
+    mpw _a, _b;								\
+    mpd _x;								\
+    _a = *_av++;							\
+    _b = *_dv;								\
+    _x = (mpd)_b - (mpd)_a - _c;					\
+    *_dv++ = MPW(_x);							\
+    if (_x >> MPW_BITS)							\
+      _c = 1;								\
+    else								\
+      _c = 0;								\
+  }									\
+  while (_c) {								\
+    mpd _x = (mpd)*_dv - (mpd)_c;					\
+    *_dv++ = MPW(_x);							\
+    if (_x >> MPW_BITS)							\
+      _c = 1;								\
+    else								\
+      _c = 0;								\
+  }									\
+} while (0)
+
+/*----- Binary polynomial arithmetic macros -------------------------------*/
+
+#define UXOR(dv, av, avl) do {						\
+  mpw *_dv = (dv);							\
+  const mpw *_av = (av), *_avl = (avl);					\
+									\
+  while (_av < _avl)							\
+    *_dv++ ^= *_av++;							\
+} while (0)
+
+#define UXOR2(dv, dvl, av, avl, bv, bvl) do {				\
+  mpw *_dv = (dv), *_dvl = (dvl);					\
+  const mpw *_av = (av), *_avl = (avl);					\
+  const mpw *_bv = (bv), *_bvl = (bvl);					\
+									\
+  while (_av < _avl || _bv < _bvl) {					\
+    mpw _a, _b;								\
+    _a = (_av < _avl) ? *_av++ : 0;					\
+    _b = (_bv < _bvl) ? *_bv++ : 0;					\
+    *_dv++ = _a ^ _b;							\
+  }									\
+  while (_dv < _dvl)							\
+    *_dv++ = 0;								\
+} while (0)
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif