/*
* Expanded form for a product c * p
* - c is a normalized bitvector constant
* - p is a power product stored in a pp_buffer object
* - n = bitsize of p
* - the expansion is returned in a bvarith_buffer or bvarith64_buffer object
* - the result is normalized
*/
void expand_bvpprod64(bvexp_table_t *table, bvarith64_buffer_t *buffer, pp_buffer_t *p, uint32_t n, uint64_t c) {
bv_vartable_t *vtbl;
bvmlist64_t *q;
pp_buffer_t *aux;
pprod_t *r;
uint64_t a;
uint32_t i, m, e, d;
thvar_t x;
assert(buffer->store == &table->store64 && buffer->ptbl == &table->pprods);
bvarith64_buffer_prepare(buffer, n);
bvarith64_buffer_set_one(buffer);
aux = p;
vtbl = table->vtbl;
if (total_degree_test64(table, vtbl, p)) {
/*
* Expansion of c * x_1^d_1 ... x_n^ d_n:
* - for a constant x_i, update c to c * a^d_i (where a = value of c)
* - if x_i is expanded to q_i, update buffer to buffer * q_i ^ d_i
* - otherwise, x_i^d_i is copied into the aux buffer
*/
aux = &table->pp;
pp_buffer_reset(aux);
m = p->len;
for (i=0; i<m; i++) {
x = p->prod[i].var;
d = p->prod[i].exp;
if (bvvar_is_const64(vtbl, x)) {
a = bvvar_val64(vtbl, x);
c *= upower64(a, d);
} else {
q = bvexp_def64(table, x);
if (q != NULL && mlist64_is_short(q, &e) && d * e <= BVEXP_DEGREE_LIMIT) {
// replace x^d by q^d in buffer
bvarith64_buffer_mul_mlist_power(buffer, q, d, &table->aux64);
} else {
// copy x^d into aux
pp_buffer_mul_varexp(aux, x, d);
}
}
}
c = norm64(c, n);
pp_buffer_normalize(aux);
}
/*
* The result is c * aux * buffer
*/
r = pprod_from_buffer(&table->pprods, aux);
bvarith64_buffer_mul_mono(buffer, c, r);
bvarith64_buffer_normalize(buffer);
}
int main(void) {
uint32_t d;
// powers of 0
for (d=0; d<16; d++) {
printf("pow32(0, %"PRIu32") = %"PRIu32"\n", d, upower32(0, d));
printf("pow64(0, %"PRIu32") = %"PRIu64"\n", d, upower64(0, d));
}
// powers of 1
for (d=0; d<16; d++) {
printf("pow32(1, %"PRIu32") = %"PRIu32"\n", d, upower32(1, d));
printf("pow64(1, %"PRIu32") = %"PRIu64"\n", d, upower64(1, d));
}
// powers of 2
for (d=0; d<80; d++) {
printf("pow32(2, %"PRIu32") = %"PRIu32"\n", d, upower32(2, d));
printf("pow64(2, %"PRIu32") = %"PRIu64"\n", d, upower64(2, d));
}
return 0;
}