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/*
* Copyright (c) 2016 Thomas Pornin <[email protected]>
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "inner.h"
/* see inner.h */
uint32_t
br_divrem(uint32_t hi, uint32_t lo, uint32_t d, uint32_t *r)
{
/* TODO: optimize this */
uint32_t q;
uint32_t ch, cf;
int k;
q = 0;
ch = EQ(hi, d);
hi = MUX(ch, 0, hi);
for (k = 31; k > 0; k --) {
int j;
uint32_t w, ctl, hi2, lo2;
j = 32 - k;
w = (hi << j) | (lo >> k);
ctl = GE(w, d) | (hi >> k);
hi2 = (w - d) >> j;
lo2 = lo - (d << k);
hi = MUX(ctl, hi2, hi);
lo = MUX(ctl, lo2, lo);
q |= ctl << k;
}
cf = GE(lo, d) | hi;
q |= cf;
*r = MUX(cf, lo - d, lo);
return q;
}
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