pd.if.org Git - zpackage/blob - tomsfastmath/src/generators/comba_mont_gen.c

   1 #include <stdio.h>
   2
   3 int main(void)
   4 {
   5    int x, y, z;
   6
   7 printf(
   8 #if 1
   9 "#ifdef TFM_SMALL_SET\n"
  10 "/* computes x/R == x (mod N) via Montgomery Reduction */\n"
  11 "void fp_montgomery_reduce_small(fp_int *a, fp_int *m, fp_digit mp)\n"
  12 "{\n"
  13 "   fp_digit c[FP_SIZE], *_c, *tmpm, mu, cy;\n"
  14 "   int      oldused, x, y, pa;\n"
  15 "\n"
  16 "#if defined(USE_MEMSET)\n"
  17 "   /* now zero the buff */\n"
  18 "   memset(c, 0, sizeof c);\n"
  19 "#endif\n"
  20 "   pa = m->used;\n"
  21 "\n"
  22 "   /* copy the input */\n"
  23 "   oldused = a->used;\n"
  24 "   for (x = 0; x < oldused; x++) {\n"
  25 "       c[x] = a->dp[x];\n"
  26 "   }\n"
  27 "#if !defined(USE_MEMSET)\n"
  28 "   for (; x < 2*pa+3; x++) {\n"
  29 "       c[x] = 0;\n"
  30 "   }\n"
  31 "#endif\n"
  32 "   MONT_START;\n"
  33 #endif
  34 "\n"
  35 "   switch (pa) {\n");
  36
  37 for (x = 1; x <= 16; x++) {
  38 if (x > 16 && (x != 32 && x != 48 && x != 64)) continue;
  39 if (x > 16) printf("#ifdef TFM_HUGE\n");
  40
  41
  42
  43 printf("      case %d:\n", x);
  44
  45 for (y = 0; y < x; y++) {
  46
  47 printf("            x = %d; cy   = 0;\n"
  48        "            LOOP_START;\n"
  49        "            _c   = c + %d;\n"
  50        "            tmpm = m->dp;\n", y, y);
  51
  52 printf("#ifdef INNERMUL8\n");
  53 for (z = 0; z+8 <= x; z += 8) {
  54 printf("            INNERMUL8; _c += 8; tmpm += 8;\n");
  55 }
  56 for (; z < x; z++) {
  57 printf("            INNERMUL; ++_c;\n");
  58 }
  59 printf("#else\n");
  60 for (z = 0; z < x; z++) {
  61 printf("            INNERMUL; ++_c;\n");
  62 }
  63 printf("#endif\n");
  64 printf("            LOOP_END;\n"
  65        "            while (cy) {\n"
  66        "               PROPCARRY;\n"
  67        "               ++_c;\n"
  68        "            }\n");
  69 }
  70 //printf("         }\n");
  71 printf("         break;\n");
  72
  73
  74
  75 #define LOOP_MACRO(stride)                                 \
  76    for (x = 0; x < stride; x++) {                          \
  77        fp_digit cy = 0;                                    \
  78        /* get Mu for this round */                         \
  79        LOOP_START;                                         \
  80        _c   = c + x;                                       \
  81        tmpm = m->dp;                                       \
  82        for (y = 0; y < stride; y++) {                      \
  83           INNERMUL;                                        \
  84           ++_c;                                            \
  85        }                                                   \
  86        LOOP_END;                                           \
  87        while (cy) {                                        \
  88            PROPCARRY;                                      \
  89            ++_c;                                           \
  90        }                                                   \
  91   }
  92
  93
  94
  95
  96
  97 if (x > 16) printf("#endif /* TFM_HUGE */\n");
  98
  99
 100 }
 101
 102 #if 1
 103
 104 printf(
 105 "  }\n"
 106 "  /* now copy out */\n"
 107 "  _c   = c + pa;\n"
 108 "  tmpm = a->dp;\n"
 109 "  for (x = 0; x < pa+1; x++) {\n"
 110 "     *tmpm++ = *_c++;\n"
 111 "  }\n"
 112 "\n"
 113 "  for (; x < oldused; x++)   {\n"
 114 "     *tmpm++ = 0;\n"
 115 "  }\n"
 116 "\n"
 117 "  MONT_FINI;\n"
 118 "\n"
 119 "  a->used = pa+1;\n"
 120 "  fp_clamp(a);\n"
 121 "\n"
 122 "  /* if A >= m then A = A - m */\n"
 123 "  if (fp_cmp_mag (a, m) != FP_LT) {\n"
 124 "    s_fp_sub (a, m, a);\n"
 125 "  }\n"
 126 "}\n\n#endif\n");
 127
 128 #endif
 129
 130
 131 return 0;
 132 }