Retire rabinpoly fingerprinting code

For now let's retire this and reintroduce it as part of the updated
pack-objects series from Geert when it is ready.

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 0 insertions, 154 deletions

diff --git a/rabinpoly.c b/rabinpoly.c
deleted file mode 100644
index c26f3829c3..0000000000
--- a/rabinpoly.c
+++ /dev/null
@@ -1,154 +0,0 @@
-/*
- *
- * Copyright (C) 1999 David Mazieres (dm@uun.org)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2, or (at
- * your option) any later version.
- *
- * This program 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
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
- * USA
- *
- */
-
-  /* Faster generic_fls */
-  /* (c) 2002, D.Phillips and Sistina Software */
-
-#include "rabinpoly.h"
-#define MSB64 0x8000000000000000ULL
-
-static inline unsigned fls8(unsigned n)
-{
-       return n & 0xf0?
-           n & 0xc0? (n >> 7) + 7: (n >> 5) + 5:
-           n & 0x0c? (n >> 3) + 3: n - ((n + 1) >> 2);
-}
-
-static inline unsigned fls16(unsigned n)
-{
-       return n & 0xff00? fls8(n >> 8) + 8: fls8(n);
-}
-
-static inline unsigned fls32(unsigned n)
-{
-       return n & 0xffff0000? fls16(n >> 16) + 16: fls16(n);
-}
-
-static inline unsigned fls64(unsigned long long n) /* should be u64 */
-{
-       return n & 0xffffffff00000000ULL? fls32(n >> 32) + 32: fls32(n);
-}
-
-
-static u_int64_t polymod (u_int64_t nh, u_int64_t nl, u_int64_t d);
-static void      polymult (u_int64_t *php, u_int64_t *plp,
-                           u_int64_t x, u_int64_t y);
-static u_int64_t polymmult (u_int64_t x, u_int64_t y, u_int64_t d);
-
-static u_int64_t poly = 0xb15e234bd3792f63ull;	// Actual polynomial
-static u_int64_t T[256];			// Lookup table for mod
-static int shift;
-
-u_int64_t append8 (u_int64_t p, u_char m)
-{ return ((p << 8) | m) ^ T[p >> shift];
-}
-
-static u_int64_t
-polymod (u_int64_t nh, u_int64_t nl, u_int64_t d)
-{ int i, k;
-  assert (d);
-  k = fls64 (d) - 1;
-  d <<= 63 - k;
-
-  if (nh) {
-    if (nh & MSB64)
-      nh ^= d;
-    for (i = 62; i >= 0; i--)
-      if (nh & 1ULL << i) {
-	nh ^= d >> (63 - i);
-	nl ^= d << (i + 1);
-      }
-  }
-  for (i = 63; i >= k; i--)
-    if (nl & 1ULL << i)
-      nl ^= d >> (63 - i);
-  return nl;
-}
-
-static void
-polymult (u_int64_t *php, u_int64_t *plp, u_int64_t x, u_int64_t y)
-{ int i;
-  u_int64_t ph = 0, pl = 0;
-  if (x & 1)
-    pl = y;
-  for (i = 1; i < 64; i++)
-    if (x & (1ULL << i)) {
-      ph ^= y >> (64 - i);
-      pl ^= y << i;
-    }
-  if (php)
-    *php = ph;
-  if (plp)
-    *plp = pl;
-}
-
-static u_int64_t
-polymmult (u_int64_t x, u_int64_t y, u_int64_t d)
-{
-  u_int64_t h, l;
-  polymult (&h, &l, x, y);
-  return polymod (h, l, d);
-}
-
-static int size = RABIN_WINDOW_SIZE;
-static u_int64_t fingerprint = 0;
-static int bufpos = -1;
-static u_int64_t U[256];
-static u_char buf[RABIN_WINDOW_SIZE];
-
-void rabin_init ()
-{ u_int64_t sizeshift = 1;
- u_int64_t T1;
-  int xshift;
-  int i, j;
-  assert (poly >= 0x100);
-  xshift = fls64 (poly) - 1;
-  shift = xshift - 8;
-  T1 = polymod (0, 1ULL << xshift, poly);
-  for (j = 0; j < 256; j++)
-    T[j] = polymmult (j, T1, poly) | ((u_int64_t) j << xshift);
-
-  for (i = 1; i < size; i++)
-    sizeshift = append8 (sizeshift, 0);
-  for (i = 0; i < 256; i++)
-    U[i] = polymmult (i, sizeshift, poly);
-  bzero (buf, sizeof (buf));
-}
-
-void
-rabin_reset ()
-{ rabin_init();
-  fingerprint = 0;
-  bzero (buf, sizeof (buf));
-}
-
-u_int64_t
-rabin_slide8 (u_char m)
-{ u_char om;
-  if (++bufpos >= size) bufpos = 0;
-
-  om = buf[bufpos];
-  buf[bufpos] = m;
-  fingerprint = append8 (fingerprint ^ U[om], m);
-
-  return fingerprint;
-}
-