isl_power_templ.c

   1 #include <isl_val_private.h>
   2
   3 #define xFN(TYPE,NAME) TYPE ## _ ## NAME
   4 #define FN(TYPE,NAME) xFN(TYPE,NAME)
   5
   6 /* Compute the given non-zero power of "map" and return the result.
   7  * If the exponent "exp" is negative, then the -exp th power of the inverse
   8  * relation is computed.
   9  */
  10 __isl_give TYPE *FN(TYPE,fixed_power)(__isl_take TYPE *map, isl_int exp)
  11 {
  12         isl_ctx *ctx;
  13         TYPE *res = NULL;
  14         isl_int r;
  15
  16         if (!map)
  17                 return NULL;
  18
  19         ctx = FN(TYPE,get_ctx)(map);
  20         if (isl_int_is_zero(exp))
  21                 isl_die(ctx, isl_error_invalid,
  22                         "expecting non-zero exponent", goto error);
  23
  24         if (isl_int_is_neg(exp)) {
  25                 isl_int_neg(exp, exp);
  26                 map = FN(TYPE,reverse)(map);
  27                 return FN(TYPE,fixed_power)(map, exp);
  28         }
  29
  30         isl_int_init(r);
  31         for (;;) {
  32                 isl_int_fdiv_r(r, exp, ctx->two);
  33
  34                 if (!isl_int_is_zero(r)) {
  35                         if (!res)
  36                                 res = FN(TYPE,copy)(map);
  37                         else {
  38                                 res = FN(TYPE,apply_range)(res,
  39                                                           FN(TYPE,copy)(map));
  40                                 res = FN(TYPE,coalesce)(res);
  41                         }
  42                         if (!res)
  43                                 break;
  44                 }
  45
  46                 isl_int_fdiv_q(exp, exp, ctx->two);
  47                 if (isl_int_is_zero(exp))
  48                         break;
  49
  50                 map = FN(TYPE,apply_range)(map, FN(TYPE,copy)(map));
  51                 map = FN(TYPE,coalesce)(map);
  52         }
  53         isl_int_clear(r);
  54
  55         FN(TYPE,free)(map);
  56         return res;
  57 error:
  58         FN(TYPE,free)(map);
  59         return NULL;
  60 }
  61
  62 /* Compute the given non-zero power of "map" and return the result.
  63  * If the exponent "exp" is negative, then the -exp th power of the inverse
  64  * relation is computed.
  65  */
  66 __isl_give TYPE *FN(TYPE,fixed_power_val)(__isl_take TYPE *map,
  67         __isl_take isl_val *exp)
  68 {
  69         if (!map || !exp)
  70                 goto error;
  71         if (!isl_val_is_int(exp))
  72                 isl_die(FN(TYPE,get_ctx)(map), isl_error_invalid,
  73                         "expecting integer exponent", goto error);
  74         map = FN(TYPE,fixed_power)(map, exp->n);
  75         isl_val_free(exp);
  76         return map;
  77 error:
  78         FN(TYPE,free)(map);
  79         isl_val_free(exp);
  80         return NULL;
  81 }