* gen-bases.c: New file, derived from mpn/mp_bases.c.

1 files changed, 182 insertions, 0 deletions

diff --git a/gen-bases.c b/gen-bases.c
new file mode 100644
index 000000000..4852ce298
--- /dev/null
+++ b/gen-bases.c
@@ -0,0 +1,182 @@
+/* Generate mp_bases data.
+
+Copyright 1991, 1993, 1994, 1996, 2000, 2002 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The GNU MP Library 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 Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include <math.h>
+
+#include "dumbmp.c"
+
+
+int    chars_per_limb;
+double chars_per_bit_exactly;
+mpz_t  big_base;
+int    normalization_steps;
+mpz_t  big_base_inverted;
+
+mpz_t  t;
+
+#define POW2_P(n)  (((n) & ((n) - 1)) == 0)
+
+unsigned int
+ulog2 (unsigned int x)
+{
+  unsigned int i;
+  for (i = 0;  x != 0;  i++)
+    x >>= 1;
+  return i;
+}
+
+void
+generate (int limb_bits, int nail_bits, int base)
+{
+  int  numb_bits = limb_bits - nail_bits;
+
+  mpz_set_ui (t, 1L);
+  mpz_mul_2exp (t, t, numb_bits);
+  mpz_set_ui (big_base, 1L);
+  chars_per_limb = 0;
+  for (;;)
+    {
+      mpz_mul_ui (big_base, big_base, (long) base);
+      if (mpz_cmp (big_base, t) >= 0)
+        break;
+      chars_per_limb++;
+    }
+
+  chars_per_bit_exactly = 0.69314718055994530942 / log ((double) base);
+
+  mpz_ui_pow_ui (big_base, (long) base, (long) chars_per_limb);
+
+  normalization_steps = limb_bits - mpz_sizeinbase (big_base, 2);
+
+  mpz_set_ui (t, 1L);
+  mpz_mul_2exp (t, t, 2*limb_bits - normalization_steps);
+  mpz_tdiv_q (big_base_inverted, t, big_base);
+  mpz_set_ui (t, 1L);
+  mpz_mul_2exp (t, t, limb_bits);
+  mpz_sub (big_base_inverted, big_base_inverted, t);
+}
+
+void
+header (int limb_bits, int nail_bits)
+{
+  int  numb_bits = limb_bits - nail_bits;
+
+  generate (limb_bits, nail_bits, 10);
+
+  printf ("/* This file generated by gen-bases.c - DO NOT EDIT. */\n");
+  printf ("\n");
+  printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
+  printf ("Error, error, this data is for %d bits\n", numb_bits);
+  printf ("#endif\n");
+  printf ("\n");
+  printf ("/* mp_bases[10] data, as literal values */\n");
+  printf ("#define MP_BASES_CHARS_PER_LIMB_10      %d\n", chars_per_limb);
+  printf ("#define MP_BASES_BIG_BASE_10            CNST_LIMB(0x");
+  mpz_out_str (0, 16, big_base);
+  printf (")\n");
+  printf ("#define MP_BASES_BIG_BASE_INVERTED_10   CNST_LIMB(0x");
+  mpz_out_str (0, 16, big_base_inverted);
+  printf (")\n");
+  printf ("#define MP_BASES_NORMALIZATION_STEPS_10 %d\n", normalization_steps);
+}
+
+void
+table (int limb_bits, int nail_bits)
+{
+  int  numb_bits = limb_bits - nail_bits;
+  int  base;
+
+  printf ("/* This file generated by gen-bases.c - DO NOT EDIT. */\n");
+  printf ("\n");
+  printf ("#include \"gmp.h\"\n");
+  printf ("#include \"gmp-impl.h\"\n");
+  printf ("\n");
+  printf ("#if GMP_NUMB_BITS != %d\n", numb_bits);
+  printf ("Error, error, this data is for %d bits\n", numb_bits);
+  printf ("#endif\n");
+  printf ("\n");
+  puts ("const struct bases mp_bases[257] =\n{");
+  puts ("  /*   0 */ { 0, 0.0, 0 },");
+  puts ("  /*   1 */ { 0, 1e37, 0 },");
+  for (base = 2; base <= 256; base++)
+    {
+      generate (limb_bits, nail_bits, base);
+
+      printf ("  /* %3u */ { ", base);
+      if (POW2_P (base))
+	{
+          printf ("%u, %.16f, 0x%x },\n",
+                  chars_per_limb, chars_per_bit_exactly, ulog2 (base) - 1);
+	}
+      else
+	{
+          printf ("%u, %.16f, CNST_LIMB(0x",
+                  chars_per_limb, chars_per_bit_exactly);
+	  mpz_out_str (0, 16, big_base);
+          printf ("), CNST_LIMB(0x");
+	  mpz_out_str (0, 16, big_base_inverted);
+          printf (") },\n");
+	}
+    }
+
+  puts ("};");
+}
+
+int
+main (int argc, char **argv)
+{
+  int  limb_bits, nail_bits;
+
+  mpz_init (big_base);
+  mpz_init (big_base_inverted);
+  mpz_init (t);
+
+  if (argc != 4)
+    {
+      fprintf (stderr, "Usage: gen-bases <header|table> <limbbits> <nailbits>\n");
+      exit (1);
+    }
+
+  limb_bits = atoi (argv[2]);
+  nail_bits = atoi (argv[3]);
+
+  if (limb_bits <= 0
+      || nail_bits < 0
+      || nail_bits >= limb_bits)
+    {
+      fprintf (stderr, "Invalid limb/nail bits: %d %d\n",
+               limb_bits, nail_bits);
+      exit (1);
+    }
+
+  if (strcmp (argv[1], "header") == 0)
+    header (limb_bits, nail_bits);
+  else if (strcmp (argv[1], "table") == 0)
+    table (limb_bits, nail_bits);
+  else
+    {
+      fprintf (stderr, "Invalid header/data choice: %s\n", argv[1]);
+      exit (1);
+    }
+
+  return 0;
+}
+