45 	size_t k;  in cond_negate()  local
50 	for (k = 0; k < len; k ++) {  in cond_negate()
53 		aw = a[k];  in cond_negate()
55 		a[k] = aw & 0x7FFF;  in cond_negate()
64  *   if neg = 0, then 0 <= a < 2*m
73 	size_t k;  in finish_mod()  local
80 	for (k = 0; k < len; k ++) {  in finish_mod()
83 		aw = a[k];  in finish_mod()
84 		mw = m[k];  in finish_mod()
97 	for (k = 0; k < len; k ++) {  in finish_mod()
100 		aw = a[k];  in finish_mod()
101 		mw = (m[k] ^ xm) & ym;  in finish_mod()
103 		a[k] = aw & 0x7FFF;  in finish_mod()
110  *   a <- (a*pa+b*pb)/(2^15)
111  *   b <- (a*qa+b*qb)/(2^15)
118  * Factors pa, pb, qa and qb must be at most 2^15 in absolute value.
126 	size_t k;  in co_reduce()  local
132 	for (k = 0; k < len; k ++) {  in co_reduce()
138 		 *   |pa| <= 2^15  in co_reduce()
139 		 *   |pb| <= 2^15  in co_reduce()
140 		 *   0 <= wa <= 2^15 - 1  in co_reduce()
141 		 *   0 <= wb <= 2^15 - 1  in co_reduce()
142 		 *   |cca| <= 2^16 - 1  in co_reduce()
144 		 *   |za| <= (2^15-1)*(2^16) + (2^16-1) = 2^31 - 1  in co_reduce()
146 		 * Thus, the new value of cca is such that |cca| <= 2^16 - 1.  in co_reduce()
149 		wa = a[k];  in co_reduce()
150 		wb = b[k];  in co_reduce()
153 		if (k > 0) {  in co_reduce()
154 			a[k - 1] = za & 0x7FFF;  in co_reduce()
155 			b[k - 1] = zb & 0x7FFF;  in co_reduce()
173  *   a <- (a*pa+b*pb)/(2^15) mod m
174  *   b <- (a*qa+b*qb)/(2^15) mod m
176  * m0i is equal to -1/m[0] mod 2^15.
178  * Factors pa, pb, qa and qb must be at most 2^15 in absolute value.
187 	size_t k;  in co_reduce_mod()  local
194 	for (k = 0; k < len; k ++) {  in co_reduce_mod()
202 		wa = a[k];  in co_reduce_mod()
203 		wb = b[k];  in co_reduce_mod()
205 			+ m[k] * (uint32_t)fa + (uint32_t)cca;  in co_reduce_mod()
207 			+ m[k] * (uint32_t)fb + (uint32_t)ccb;  in co_reduce_mod()
208 		if (k > 0) {  in co_reduce_mod()
209 			a[k - 1] = za & 0x7FFF;  in co_reduce_mod()
210 			b[k - 1] = zb & 0x7FFF;  in co_reduce_mod()
232 	 *   -m <= a < 2*m  in co_reduce_mod()
233 	 *   -m <= b < 2*m  in co_reduce_mod()
263 	 *   - If a is even, then a <- a/2 and u <- u/2 mod m.  in br_i15_moddiv()
264 	 *   - Otherwise, if b is even, then b <- b/2 and v <- v/2 mod m.  in br_i15_moddiv()
265 	 *   - Otherwise, if a > b, then a <- (a-b)/2 and u <- (u-v)/2 mod m.  in br_i15_moddiv()
266 	 *   - Otherwise, b <- (b-a)/2 and v <- (v-u)/2 mod m.  in br_i15_moddiv()
274 	 * if m has bit length k bits, then 2k-2 steps are sufficient.  in br_i15_moddiv()
287 	 *   a' = (a*pa + b*pb) / (2^15)  in br_i15_moddiv()
288 	 *   b' = (a*qa + b*qb) / (2^15)  in br_i15_moddiv()
304 	size_t len, k;  in br_i15_moddiv()  local
377 		 * such that a' and b' are both multiple of 2^15, but are  in br_i15_moddiv()
388 			 *   a <- (a-b)/2 if: a is odd, b is odd, a_hi > b_hi  in br_i15_moddiv()
389 			 *   b <- (b-a)/2 if: a is odd, b is odd, a_hi <= b_hi  in br_i15_moddiv()
390 			 *   a <- a/2 if: a is even  in br_i15_moddiv()
391 			 *   b <- b/2 if: a is odd, b is even  in br_i15_moddiv()
393 			 * We multiply a_lo and b_lo by 2 at each  in br_i15_moddiv()
394 			 * iteration, thus a division by 2 really is a  in br_i15_moddiv()
395 			 * non-multiplication by 2.  in br_i15_moddiv()
402 			 * cA = 1 if a is divided by 2, 0 otherwise  in br_i15_moddiv()
407 			 *   if a is not divided by 2, b is.  in br_i15_moddiv()
447 		qa -= qa * (r & 2);  in br_i15_moddiv()
448 		qb -= qb * (r & 2);  in br_i15_moddiv()
460 	for (k = 1; k < len; k ++) {  in br_i15_moddiv()
461 		r |= a[k] | b[k];  in br_i15_moddiv()
462 		u[k] |= v[k];  in br_i15_moddiv()