+/*
+ * Copyright © 2013 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <ao_int64.h>
+
+__pdata ao_int64_t *__data ao_64r, *__data ao_64a, *__data ao_64b;
+
+void ao_plus64(__pdata ao_int64_t *r, __pdata ao_int64_t *a, __pdata ao_int64_t *b) __FATTR {
+ __LOCAL uint32_t t;
+
+ r->high = a->high + b->high;
+ t = a->low + b->low;
+ if (t < a->low)
+ r->high++;
+ r->low = t;
+}
+
+void ao_minus64(__pdata ao_int64_t *r, __pdata ao_int64_t *a, __pdata ao_int64_t *b) __FATTR {
+ __LOCAL uint32_t t;
+
+ r->high = a->high - b->high;
+ t = a->low - b->low;
+ if (t > a->low)
+ r->high--;
+ r->low = t;
+}
+
+void ao_rshift64(__pdata ao_int64_t *r, __pdata ao_int64_t *a, uint8_t d) __FATTR {
+ if (d < 32) {
+ r->low = a->low >> d;
+ if (d)
+ r->low |= a->high << (32 - d);
+ r->high = (int32_t) a->high >> d;
+ } else {
+ d &= 0x1f;
+ r->low = (int32_t) a->high >> d;
+ r->high = 0;
+ }
+}
+
+void ao_lshift64(__pdata ao_int64_t *r, __pdata ao_int64_t *a, uint8_t d) __FATTR {
+ if (d < 32) {
+ r->high = a->high << d;
+ if (d)
+ r->high |= a->low >> (32 - d);
+ r->low = a->low << d;
+ } else {
+ d &= 0x1f;
+ r->high = a->low << d;
+ r->low = 0;
+ }
+}
+
+static void ao_umul64_32_32(__ARG ao_int64_t *r, uint32_t a, uint32_t b) __reentrant {
+ __LOCAL uint32_t s;
+ __LOCAL ao_int64_t t;
+ r->low = (uint32_t) (uint16_t) a * (uint16_t) b;
+ r->high = (uint32_t) (uint16_t) (a >> 16) * (uint16_t) (b >> 16);
+
+ s = (uint32_t) (uint16_t) (a >> 16) * (uint16_t) b;
+
+ t.high = s >> 16;
+ t.low = s << 16;
+ ao_plus64(r, r, &t);
+
+ s = (uint32_t) (uint16_t) a * (uint16_t) (b >> 16);
+
+ t.high = s >> 16;
+ t.low = s << 16;
+ ao_plus64(r, r, &t);
+}
+
+void ao_neg64(__pdata ao_int64_t *r, __pdata ao_int64_t *a) __FATTR {
+ r->high = ~a->high;
+ if (!(r->low = ~a->low + 1))
+ r->high++;
+}
+
+void ao_mul64_32_32(__ARG ao_int64_t *r, int32_t a, int32_t b) __FATTR {
+ uint8_t negative = 0;
+
+ if (a < 0) {
+ a = -a;
+ ++negative;
+ }
+ if (b < 0) {
+ b = -b;
+ --negative;
+ }
+ ao_umul64_32_32(r, a, b);
+ if (negative)
+ ao_neg64(r, r);
+}
+
+static void ao_umul64(__ARG ao_int64_t *r, __ARG ao_int64_t *a, __ARG ao_int64_t *b) __reentrant {
+ __LOCAL ao_int64_t r2, r3;
+
+ ao_umul64_32_32(&r2, a->high, b->low);
+ ao_umul64_32_32(&r3, a->low, b->high);
+ ao_umul64_32_32(r, a->low, b->low);
+
+ r->high += r2.low + r3.low;
+}
+
+static __ARG ao_int64_t ap, bp;
+
+void ao_mul64(__ARG ao_int64_t *r, __ARG ao_int64_t *a, __ARG ao_int64_t *b) __FATTR {
+ uint8_t negative = 0;
+
+ if (ao_int64_negativep(a)) {
+ ao_neg64(&ap, a);
+ a = ≈
+ ++negative;
+ }
+ if (ao_int64_negativep(b)) {
+ ao_neg64(&bp, b);
+ b = &bp;
+ --negative;
+ }
+ ao_umul64(r, a, b);
+ if (negative)
+ ao_neg64(r, r);
+}
+
+static void ao_umul64_64_16(__ARG ao_int64_t *r, __ARG ao_int64_t *a, uint16_t b) __reentrant {
+ __LOCAL uint32_t h;
+
+ h = a->high * b;
+ ao_umul64_32_32(r, a->low, b);
+ r->high += h;
+}
+
+void ao_mul64_64_16(__ARG ao_int64_t *r, __ARG ao_int64_t *a, __ARG uint16_t b) __FATTR {
+ uint8_t negative = 0;
+
+ if ((int32_t) a->high < 0) {
+ ao_neg64(&ap, a);
+ a = ≈
+ negative++;
+ } else
+ ao_umul64_64_16(r, a, b);
+ if (negative)
+ ao_neg64(r, r);
+}