Update relic_bn_mul_low.c

relic-toolkit · Apr 26, 2024 · b89695c · b89695c
1 parent bf8c7a3
commit b89695c
Showing 1 changed file with 14 additions and 0 deletions.
diff --git a/src/low/x64-asm-6l/relic_bn_mul_low.c b/src/low/x64-asm-6l/relic_bn_mul_low.c
@@ -52,6 +52,20 @@ void bn_muln_low(dig_t *c, const dig_t *a, const dig_t *b, int size) {
 	mpn_mul_n(c, a, b, size);
 }
 
+dig_t bn_muls_low(dig_t *c, const dig_t *a, dig_t sa, dis_t digit, int size) {
+	dig_t carry, sign, sd = digit >> (RLC_DIG - 1);
+
+	sa = -sa;
+	sign = sa ^ sd;
+	digit = (digit ^ sd) - sd;
+
+	carry = mpn_mul_1(c, a, size, digit);
+	for (size_t i = 0; i < size; i++) {
+		c[i] = c[i] ^ sign;
+	}
+	return (carry ^ sign) + mpn_add_1(c, c, size, -sign);
+}
+
 void bn_muld_low(dig_t *c, const dig_t *a, int sizea, const dig_t *b, int sizeb,
 		int low, int high) {
 	(void)low;