1 | #include <isl_val_private.h> |
2 | |
3 | #define xFN(TYPE,NAME) TYPE ## _ ## NAME |
4 | #define FN(TYPE,NAME) xFN(TYPE,NAME) |
5 | |
6 | /* Helper function for isl_*_fixed_power that applies (a copy of) "map2" |
7 | * to the range of "map1" and returns the result. |
8 | * |
9 | * The result is coalesced in an attempt to reduce the number of disjuncts |
10 | * that result from repeated applications. |
11 | * Similarly, look for implicit equality constraints in an attempt |
12 | * to reduce the number of local variables that get introduced |
13 | * during the repeated applications. |
14 | */ |
15 | static __isl_give TYPE *FN(TYPE,fixed_power_apply)(__isl_take TYPE *map1, |
16 | __isl_keep TYPE *map2) |
17 | { |
18 | TYPE *res; |
19 | |
20 | res = FN(TYPE,apply_range)(map1, FN(TYPE,copy)(map: map2)); |
21 | res = FN(TYPE,detect_equalities)(map: res); |
22 | res = FN(TYPE,coalesce)(map: res); |
23 | |
24 | return res; |
25 | } |
26 | |
27 | /* Compute the given non-zero power of "map" and return the result. |
28 | * If the exponent "exp" is negative, then the -exp th power of the inverse |
29 | * relation is computed. |
30 | */ |
31 | __isl_give TYPE *FN(TYPE,fixed_power)(__isl_take TYPE *map, isl_int exp) |
32 | { |
33 | isl_ctx *ctx; |
34 | TYPE *res = NULL; |
35 | isl_int r; |
36 | |
37 | if (!map) |
38 | return NULL; |
39 | |
40 | ctx = FN(TYPE,get_ctx)(map); |
41 | if (isl_int_is_zero(exp)) |
42 | isl_die(ctx, isl_error_invalid, |
43 | "expecting non-zero exponent" , goto error); |
44 | |
45 | if (isl_int_is_neg(exp)) { |
46 | isl_int_neg(exp, exp); |
47 | map = FN(TYPE,reverse)(map); |
48 | return FN(TYPE,fixed_power)(map, exp); |
49 | } |
50 | |
51 | isl_int_init(r); |
52 | for (;;) { |
53 | isl_int_fdiv_r(r, exp, ctx->two); |
54 | |
55 | if (!isl_int_is_zero(r)) { |
56 | if (!res) |
57 | res = FN(TYPE,copy)(map); |
58 | else |
59 | res = FN(TYPE,fixed_power_apply)(map1: res, map2: map); |
60 | if (!res) |
61 | break; |
62 | } |
63 | |
64 | isl_int_fdiv_q(exp, exp, ctx->two); |
65 | if (isl_int_is_zero(exp)) |
66 | break; |
67 | |
68 | map = FN(TYPE,fixed_power_apply)(map1: map, map2: map); |
69 | } |
70 | isl_int_clear(r); |
71 | |
72 | FN(TYPE,free)(map); |
73 | return res; |
74 | error: |
75 | FN(TYPE,free)(map); |
76 | return NULL; |
77 | } |
78 | |
79 | /* Compute the given non-zero power of "map" and return the result. |
80 | * If the exponent "exp" is negative, then the -exp th power of the inverse |
81 | * relation is computed. |
82 | */ |
83 | __isl_give TYPE *FN(TYPE,fixed_power_val)(__isl_take TYPE *map, |
84 | __isl_take isl_val *exp) |
85 | { |
86 | if (!map || !exp) |
87 | goto error; |
88 | if (!isl_val_is_int(v: exp)) |
89 | isl_die(FN(TYPE,get_ctx)(map), isl_error_invalid, |
90 | "expecting integer exponent" , goto error); |
91 | map = FN(TYPE,fixed_power)(map, exp: exp->n); |
92 | isl_val_free(v: exp); |
93 | return map; |
94 | error: |
95 | FN(TYPE,free)(map); |
96 | isl_val_free(v: exp); |
97 | return NULL; |
98 | } |
99 | |