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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 *q = point_copy(curve->neutral);
point_t *points[{{ 2 ** (scalarmult.width - 2) }}];
{%- if scalarmult.precompute_negation %}
point_t *points_neg[{{ 2 ** (scalarmult.width - 2) }}];
{%- else %}
point_t *neg = point_new();
{%- endif %}
point_t *current = point_copy(point);
point_t *dbl = point_new();
point_dbl(current, curve, dbl);
for (long i = 0; i < {{ 2 ** (scalarmult.width - 2) }}; i++) {
points[i] = point_copy(current);
{%- if scalarmult.precompute_negation %}
points_neg[i] = point_copy(current);
point_neg(points_neg[i], curve, points_neg[i]);
{%- endif %}
if (i != {{ 2 ** (scalarmult.width - 2) }} - 1) {
point_add(current, dbl, curve, current);
}
}
point_free(current);
point_free(dbl);
wnaf_t *naf = bn_wnaf(scalar, {{ scalarmult.width }});
for (long i = 0; i < naf->length; i++) {
point_dbl(q, curve, q);
int8_t val = naf->data[i];
if (val > 0) {
point_accumulate(q, points[(val - 1) / 2], curve, q);
} else if (val < 0) {
{%- if scalarmult.precompute_negation %}
point_accumulate(q, points_neg[(-val - 1) / 2], curve, q);
{%- else %}
point_neg(points[(-val - 1) / 2], curve, neg);
point_accumulate(q, neg, curve, q);
{%- endif %}
}
}
bn_naf_clear(naf);
{%- if "scl" in scalarmult.formulas %}
point_scl(q, curve, q);
{%- endif %}
point_set(q, out);
for (long i = 0; i < {{ 2 ** (scalarmult.width - 2) }}; i++) {
point_free(points[i]);
{%- if scalarmult.precompute_negation %}
point_free(points_neg[i]);
{%- endif %}
}
{%- if not scalarmult.precompute_negation %}
point_free(neg);
{%- endif %}
point_free(q);
}
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