Implement efficient reduction for pleasant-looking primes.

[u/mdw/catacomb] / mpx.h

diff --git a/mpx.h b/mpx.h
index bf73912..13b63cc 100644 (file)
--- a/mpx.h
+++ b/mpx.h
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: mpx.h,v 1.16 2003/05/16 09:09:24 mdw Exp $
+ * $Id: mpx.h,v 1.17 2004/03/27 00:04:46 mdw Exp $
  *
  * Low level multiprecision arithmetic
  *
@@ -30,6 +30,9 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: mpx.h,v $
+ * Revision 1.17  2004/03/27 00:04:46  mdw
+ * Implement efficient reduction for pleasant-looking primes.
+ *
  * Revision 1.16  2003/05/16 09:09:24  mdw
  * Fix @mp_lsl2c@.  Turns out to be surprisingly tricky.
  *
@@ -560,6 +563,22 @@ extern void mpx_uadd(mpw */*dv*/, mpw */*dvl*/,
 
 extern void mpx_uaddn(mpw */*dv*/, mpw */*dvl*/, mpw /*n*/);
 
+/* --- @mpx_uaddnlsl@ --- *
+ *
+ * Arguments:  @mpw *dv, *dvl@ = destination and first argument vector
+ *             @mpw a@ = second argument
+ *             @unsigned o@ = offset in bits
+ *
+ * Returns:    ---
+ *
+ * Use:                Computes %$d + 2^o a$%.  If the result overflows then
+ *             high-order bits are discarded, as usual.  We must have
+ *             @0 < o < MPW_BITS@.
+ */
+
+extern void mpx_uaddnlsl(mpw */*dv*/, mpw */*dvl*/,
+                        mpw /*a*/, unsigned /*o*/);
+
 /* --- @mpx_usub@ --- *
  *
  * Arguments:  @mpw *dv, *dvl@ = destination vector base and limit
@@ -607,6 +626,23 @@ extern void mpx_usub(mpw */*dv*/, mpw */*dvl*/,
 
 extern void mpx_usubn(mpw */*dv*/, mpw */*dvl*/, mpw /*n*/);
 
+/* --- @mpx_usubnlsl@ --- *
+ *
+ * Arguments:  @mpw *dv, *dvl@ = destination and first argument vector
+ *             @mpw a@ = second argument
+ *             @unsigned o@ = offset in bits
+ *
+ * Returns:    ---
+ *
+ * Use:                Computes %$d - 2^o a$%.  If the result overflows then
+ *             high-order bits are discarded, as usual, so you get two's
+ *             complement.  Which might be what you wanted...  We must have
+ *             @0 < o < MPW_BITS@.
+ */
+
+extern void mpx_usubnlsl(mpw */*dv*/, mpw */*dvl*/,
+                        mpw /*a*/, unsigned /*o*/);
+
 /* --- @mpx_umul@ --- *
  *
  * Arguments:  @mpw *dv, *dvl@ = destination vector base and limit