(__gmp_rand_scheme): Clean up some. Use slightly better multipliers.

1 files changed, 45 insertions, 37 deletions

diff --git a/rand.c b/rand.c
index 79f930888..c1baa3274 100644
--- a/rand.c
+++ b/rand.c
@@ -29,47 +29,55 @@ MA 02111-1307, USA. */
    containing all zeros. */
 static __gmp_rand_lc_scheme_struct __gmp_rand_scheme[] =
 {
-  /* FIXME: Testing.  Remove. */
-  {8, "7", 0, "256"},
-
+  /* FIXME: Remove. */
+  {8, "7", 0, "256"},		/* Test. */
   {31,				/* fbsd rand(3) */
    "1103515245",		/* a (multiplier) */
    12345,			/* c (adder) */
    "0x80000000"},		/* m (modulo) = 2^31 */
 
-  /* The multipliers are all between 0.01m and 0.99m, and are
-     congruent to 5 (mod 8). */
-
-  /* FIXME: Run a spectral test on each of the generators and verify
-     that the multiplier is good. */
-
-  {32, "42964341", 	 1, "0x100000000"}, /* pass: spect(6); merit>1 */
-  {33, "85899933", 	 1, "0x200000000"}, /* pass: spect(6); merit>1 */
-  {34, "171799469", 	 1, "0x400000000"}, /* pass: spect(6); merit>1 */
-  {35, "343598461", 	 1, "0x800000000"}, /* pass: spect(6); merit>1 */
-
-  {36, "687196269", 	 1, "0x1000000000"}, /* pass: spect(6); merit>1 */
-  {37, "1374564613", 	 1, "0x2000000000"}, /* pass: spect(6); merit>3 */
-  {38, "2749193437", 	 1, "0x4000000000"}, /* pass: spect(6); merit>3.1 */
-  {39, "5497652029", 	 1, "0x8000000000"}, /* pass: spect(6); merit>3 */
-  {40, "10995138701", 	 1, "0x10000000000"}, /* pass: spect(6); merit>2.5 */
-
-  {56, "720575942521269",	/* pass: spect(6); merit>2 */
-    1, "0x100000000000000"},
-  {64, "184467440744758277",	/* pass: spect(6) (no merit >1 up to 184467440750242261) */
-    1, "0x10000000000000000"},
-  {100, "12676506002282294015055173877", /* low merit2; working: agnesi (12676506002282294015146266925) */
-    1, "0x10000000000000000000000000"},	
-  {128, "3402823669209384634633746074363516093", /* low merit2+3; working: dupont */
-    1, "0x100000000000000000000000000000000"},
-  {156, "913438523331814323877303020447676887284957853", /* working: bob */
-    1, "0x1000000000000000000000000000000000000000"},
-  {196, "1004336277661868922213726307713226626576376871114287459829", /* low merit*; working: dupond (1004336277661868922213726307713226626576376871114345439621) */
-    1, "0x10000000000000000000000000000000000000000000000000"},
-  {200, "16069380442589902755419620923411626025222029937827928353021", /* working: haj */
-    1, "0x100000000000000000000000000000000000000000000000000"},
-  {256, "1157920892373161954235709850086879078532699846656405640394575840079131296413",	/* working: moufang */
-    1, "0x10000000000000000000000000000000000000000000000000000000000000000"},
+  /*  {31, "22298549", 	     1, "0x80000000"},*/
+				/* merit >= 1; no merit > 3 up to 32845469 */
+
+  /* The following multipliers are all between 0.01m and 0.99m, and
+     are congruent to 5 (mod 8).  They all pass the spectral test with
+     Vt >= 2^(30/t) and merit >= 0.1.
+
+     Up to and including 40 bits, merit >= 3.
+     Up to and including 56 bits, merit >= 2.
+     Up to and including 64 bits, merit >= 1.  */
+
+  {32, "43840821", 	     1, "0x100000000"},
+  {33, "85943917", 	     1, "0x200000000"},
+  {34, "171799469", 	     1, "0x400000000"},
+  {35, "343825285", 	     1, "0x800000000"},
+  {36, "687285701", 	     1, "0x1000000000"},
+  {37, "1374564613", 	     1, "0x2000000000"},
+  {38, "2749193437", 	     1, "0x4000000000"},
+  {39, "5497652029", 	     1, "0x8000000000"},
+  {40, "10995212661", 	     1, "0x10000000000"},
+  {56, "720575942521269",    1, "0x100000000000000"},
+				/* no merit >3 up to 720575942889605 */
+  {64, "184467440744758277", 1, "0x10000000000000000"},
+				/* no merit >2 up to 184467440750242261 */
+
+  {100, "12676506002282294015055173877", 1, "0x10000000000000000000000000"},	
+				/* low merit2; (12676506002282294015146266925) */
+  {128, "3402823669209384634633746074363516093",
+   1, "0x100000000000000000000000000000000"},
+				/* low merit2+3; (3402823669209384634633746074396970501) */
+  {156, "913438523331814323877303020447676887284958173",
+   1, "0x1000000000000000000000000000000000000000"},
+				/* low merit* */
+  {196, "1004336277661868922213726307713226626576376871114287459829",
+   1, "0x10000000000000000000000000000000000000000000000000"},
+				/* low merit*; (1004336277661868922213726307713226626576376871114345439621) */
+  {200, "16069380442589902755419620923411626025222029937827928353349",
+   1, "0x100000000000000000000000000000000000000000000000000"},
+				/* low merit*; */
+  {256, "1157920892373161954235709850086879078532699846656405640394575840079131296733",
+   1, "0x10000000000000000000000000000000000000000000000000000000000000000"},
+				/* low merit*; */
 
   {0, NULL,  0, NULL}		/* End of array. */
 };
@@ -100,7 +108,7 @@ gmp_rand_init (s, alg, size, seed)
 
 
       /* Pick a scheme. */
-	for (sp = __gmp_rand_scheme; sp->bits; sp++)
+	for (sp = __gmp_rand_scheme; sp->bits != 0; sp++)
 	  if (sp->bits >= size)
 	    break;
 	if (!sp->bits)		/* Nothing big enough found. */