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#include "mult.h"
#include "point.h"
static void scalar_mult_inner(bn_t *scalar, point_t *point, curve_t *curve, point_t *out) {
point_t *points[{{ 2 ** (scalarmult.width - 1) }}];
{% if scalarmult.precompute_negation %}
point_t *points_neg[{{ 2 ** (scalarmult.width - 1) }}];
{% endif %}
point_t *current = point_copy(point);
point_t *dbl = point_new();
point_dbl(current, curve, dbl);
points[0] = point_copy(current);
{% if scalarmult.precompute_negation %}
points_neg[0] = point_new();
point_neg(points[0], curve, points_neg[0]);
{% endif %}
{% if scalarmult.width > 1 %}
points[1] = point_copy(dbl);
{% if scalarmult.precompute_negation %}
points_neg[1] = point_new();
point_neg(points[1], curve, points_neg[1]);
{% endif %}
{% endif %}
point_set(dbl, current);
{% if scalarmult.width > 2 %}
for (long i = 2; i < {{ 2 ** (scalarmult.width - 1) }}; i++) {
point_add(current, point, curve, current);
points[i] = point_copy(current);
{% if scalarmult.precompute_negation %}
points_neg[i] = point_new();
point_neg(points[i], curve, points_neg[i]);
{% endif %}
}
{% endif %}
point_free(current);
point_free(dbl);
size_t bits = bn_bit_length(&curve->n);
booth_t *bs = bn_booth(scalar, {{ scalarmult.width }}, bits);
point_t *q = point_copy(curve->neutral);
point_t *neg = point_new();
for (long i = 0; i < bs->length; i++) {
for (long j = 0; j < {{ scalarmult.width }}; j++) {
point_dbl(q, curve, q);
}
int32_t val = bs->data[i];
if (val > 0) {
point_accumulate(q, points[val - 1], curve, q);
} else if (val < 0) {
{% if scalarmult.precompute_negation %}
point_accumulate(q, points_neg[-val - 1], curve, q);
{% else %}
point_neg(points[-val - 1], curve, neg);
point_accumulate(q, neg, curve, q);
{% endif %}
}
}
bn_booth_clear(bs);
point_free(neg);
{%- if "scl" in scalarmult.formulas %}
point_scl(q, curve, q);
{%- endif %}
point_set(q, out);
for (long i = 0; i < {{ 2 ** (scalarmult.width - 1) }}; i++) {
point_free(points[i]);
{% if scalarmult.precompute_negation %}
point_free(points_neg[i]);
{% endif %}
}
point_free(q);
}
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