x86_64-gcc.c revision 306195
1#include "../bn_lcl.h"
2#if !(defined(__GNUC__) && __GNUC__>=2)
3# include "../bn_asm.c"         /* kind of dirty hack for Sun Studio */
4#else
5/*-
6 * x86_64 BIGNUM accelerator version 0.1, December 2002.
7 *
8 * Implemented by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
9 * project.
10 *
11 * Rights for redistribution and usage in source and binary forms are
12 * granted according to the OpenSSL license. Warranty of any kind is
13 * disclaimed.
14 *
15 * Q. Version 0.1? It doesn't sound like Andy, he used to assign real
16 *    versions, like 1.0...
17 * A. Well, that's because this code is basically a quick-n-dirty
18 *    proof-of-concept hack. As you can see it's implemented with
19 *    inline assembler, which means that you're bound to GCC and that
20 *    there might be enough room for further improvement.
21 *
22 * Q. Why inline assembler?
23 * A. x86_64 features own ABI which I'm not familiar with. This is
24 *    why I decided to let the compiler take care of subroutine
25 *    prologue/epilogue as well as register allocation. For reference.
26 *    Win64 implements different ABI for AMD64, different from Linux.
27 *
28 * Q. How much faster does it get?
29 * A. 'apps/openssl speed rsa dsa' output with no-asm:
30 *
31 *                        sign    verify    sign/s verify/s
32 *      rsa  512 bits   0.0006s   0.0001s   1683.8  18456.2
33 *      rsa 1024 bits   0.0028s   0.0002s    356.0   6407.0
34 *      rsa 2048 bits   0.0172s   0.0005s     58.0   1957.8
35 *      rsa 4096 bits   0.1155s   0.0018s      8.7    555.6
36 *                        sign    verify    sign/s verify/s
37 *      dsa  512 bits   0.0005s   0.0006s   2100.8   1768.3
38 *      dsa 1024 bits   0.0014s   0.0018s    692.3    559.2
39 *      dsa 2048 bits   0.0049s   0.0061s    204.7    165.0
40 *
41 *    'apps/openssl speed rsa dsa' output with this module:
42 *
43 *                        sign    verify    sign/s verify/s
44 *      rsa  512 bits   0.0004s   0.0000s   2767.1  33297.9
45 *      rsa 1024 bits   0.0012s   0.0001s    867.4  14674.7
46 *      rsa 2048 bits   0.0061s   0.0002s    164.0   5270.0
47 *      rsa 4096 bits   0.0384s   0.0006s     26.1   1650.8
48 *                        sign    verify    sign/s verify/s
49 *      dsa  512 bits   0.0002s   0.0003s   4442.2   3786.3
50 *      dsa 1024 bits   0.0005s   0.0007s   1835.1   1497.4
51 *      dsa 2048 bits   0.0016s   0.0020s    620.4    504.6
52 *
53 *    For the reference. IA-32 assembler implementation performs
54 *    very much like 64-bit code compiled with no-asm on the same
55 *    machine.
56 */
57
58# if defined(_WIN64) || !defined(__LP64__)
59#  define BN_ULONG unsigned long long
60# else
61#  define BN_ULONG unsigned long
62# endif
63
64# undef mul
65# undef mul_add
66
67/*-
68 * "m"(a), "+m"(r)      is the way to favor DirectPath ��-code;
69 * "g"(0)               let the compiler to decide where does it
70 *                      want to keep the value of zero;
71 */
72# define mul_add(r,a,word,carry) do {   \
73        register BN_ULONG high,low;     \
74        asm ("mulq %3"                  \
75                : "=a"(low),"=d"(high)  \
76                : "a"(word),"m"(a)      \
77                : "cc");                \
78        asm ("addq %2,%0; adcq %3,%1"   \
79                : "+r"(carry),"+d"(high)\
80                : "a"(low),"g"(0)       \
81                : "cc");                \
82        asm ("addq %2,%0; adcq %3,%1"   \
83                : "+m"(r),"+d"(high)    \
84                : "r"(carry),"g"(0)     \
85                : "cc");                \
86        carry=high;                     \
87        } while (0)
88
89# define mul(r,a,word,carry) do {       \
90        register BN_ULONG high,low;     \
91        asm ("mulq %3"                  \
92                : "=a"(low),"=d"(high)  \
93                : "a"(word),"g"(a)      \
94                : "cc");                \
95        asm ("addq %2,%0; adcq %3,%1"   \
96                : "+r"(carry),"+d"(high)\
97                : "a"(low),"g"(0)       \
98                : "cc");                \
99        (r)=carry, carry=high;          \
100        } while (0)
101# undef sqr
102# define sqr(r0,r1,a)                   \
103        asm ("mulq %2"                  \
104                : "=a"(r0),"=d"(r1)     \
105                : "a"(a)                \
106                : "cc");
107
108BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num,
109                          BN_ULONG w)
110{
111    BN_ULONG c1 = 0;
112
113    if (num <= 0)
114        return (c1);
115
116    while (num & ~3) {
117        mul_add(rp[0], ap[0], w, c1);
118        mul_add(rp[1], ap[1], w, c1);
119        mul_add(rp[2], ap[2], w, c1);
120        mul_add(rp[3], ap[3], w, c1);
121        ap += 4;
122        rp += 4;
123        num -= 4;
124    }
125    if (num) {
126        mul_add(rp[0], ap[0], w, c1);
127        if (--num == 0)
128            return c1;
129        mul_add(rp[1], ap[1], w, c1);
130        if (--num == 0)
131            return c1;
132        mul_add(rp[2], ap[2], w, c1);
133        return c1;
134    }
135
136    return (c1);
137}
138
139BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
140{
141    BN_ULONG c1 = 0;
142
143    if (num <= 0)
144        return (c1);
145
146    while (num & ~3) {
147        mul(rp[0], ap[0], w, c1);
148        mul(rp[1], ap[1], w, c1);
149        mul(rp[2], ap[2], w, c1);
150        mul(rp[3], ap[3], w, c1);
151        ap += 4;
152        rp += 4;
153        num -= 4;
154    }
155    if (num) {
156        mul(rp[0], ap[0], w, c1);
157        if (--num == 0)
158            return c1;
159        mul(rp[1], ap[1], w, c1);
160        if (--num == 0)
161            return c1;
162        mul(rp[2], ap[2], w, c1);
163    }
164    return (c1);
165}
166
167void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
168{
169    if (n <= 0)
170        return;
171
172    while (n & ~3) {
173        sqr(r[0], r[1], a[0]);
174        sqr(r[2], r[3], a[1]);
175        sqr(r[4], r[5], a[2]);
176        sqr(r[6], r[7], a[3]);
177        a += 4;
178        r += 8;
179        n -= 4;
180    }
181    if (n) {
182        sqr(r[0], r[1], a[0]);
183        if (--n == 0)
184            return;
185        sqr(r[2], r[3], a[1]);
186        if (--n == 0)
187            return;
188        sqr(r[4], r[5], a[2]);
189    }
190}
191
192BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
193{
194    BN_ULONG ret, waste;
195
196 asm("divq      %4":"=a"(ret), "=d"(waste)
197 :     "a"(l), "d"(h), "r"(d)
198 :     "cc");
199
200    return ret;
201}
202
203BN_ULONG bn_add_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
204                      int n)
205{
206    BN_ULONG ret;
207    size_t i = 0;
208
209    if (n <= 0)
210        return 0;
211
212    asm volatile ("       subq    %0,%0           \n" /* clear carry */
213                  "       jmp     1f              \n"
214                  ".p2align 4                     \n"
215                  "1:     movq    (%4,%2,8),%0    \n"
216                  "       adcq    (%5,%2,8),%0    \n"
217                  "       movq    %0,(%3,%2,8)    \n"
218                  "       lea     1(%2),%2        \n"
219                  "       loop    1b              \n"
220                  "       sbbq    %0,%0           \n":"=&r" (ret), "+c"(n),
221                  "+r"(i)
222                  :"r"(rp), "r"(ap), "r"(bp)
223                  :"cc", "memory");
224
225    return ret & 1;
226}
227
228# ifndef SIMICS
229BN_ULONG bn_sub_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
230                      int n)
231{
232    BN_ULONG ret;
233    size_t i = 0;
234
235    if (n <= 0)
236        return 0;
237
238    asm volatile ("       subq    %0,%0           \n" /* clear borrow */
239                  "       jmp     1f              \n"
240                  ".p2align 4                     \n"
241                  "1:     movq    (%4,%2,8),%0    \n"
242                  "       sbbq    (%5,%2,8),%0    \n"
243                  "       movq    %0,(%3,%2,8)    \n"
244                  "       lea     1(%2),%2        \n"
245                  "       loop    1b              \n"
246                  "       sbbq    %0,%0           \n":"=&r" (ret), "+c"(n),
247                  "+r"(i)
248                  :"r"(rp), "r"(ap), "r"(bp)
249                  :"cc", "memory");
250
251    return ret & 1;
252}
253# else
254/* Simics 1.4<7 has buggy sbbq:-( */
255#  define BN_MASK2 0xffffffffffffffffL
256BN_ULONG bn_sub_words(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n)
257{
258    BN_ULONG t1, t2;
259    int c = 0;
260
261    if (n <= 0)
262        return ((BN_ULONG)0);
263
264    for (;;) {
265        t1 = a[0];
266        t2 = b[0];
267        r[0] = (t1 - t2 - c) & BN_MASK2;
268        if (t1 != t2)
269            c = (t1 < t2);
270        if (--n <= 0)
271            break;
272
273        t1 = a[1];
274        t2 = b[1];
275        r[1] = (t1 - t2 - c) & BN_MASK2;
276        if (t1 != t2)
277            c = (t1 < t2);
278        if (--n <= 0)
279            break;
280
281        t1 = a[2];
282        t2 = b[2];
283        r[2] = (t1 - t2 - c) & BN_MASK2;
284        if (t1 != t2)
285            c = (t1 < t2);
286        if (--n <= 0)
287            break;
288
289        t1 = a[3];
290        t2 = b[3];
291        r[3] = (t1 - t2 - c) & BN_MASK2;
292        if (t1 != t2)
293            c = (t1 < t2);
294        if (--n <= 0)
295            break;
296
297        a += 4;
298        b += 4;
299        r += 4;
300    }
301    return (c);
302}
303# endif
304
305/* mul_add_c(a,b,c0,c1,c2)  -- c+=a*b for three word number c=(c2,c1,c0) */
306/* mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0) */
307/* sqr_add_c(a,i,c0,c1,c2)  -- c+=a[i]^2 for three word number c=(c2,c1,c0) */
308/*
309 * sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number
310 * c=(c2,c1,c0)
311 */
312
313/*
314 * Keep in mind that carrying into high part of multiplication result
315 * can not overflow, because it cannot be all-ones.
316 */
317# if 0
318/* original macros are kept for reference purposes */
319#  define mul_add_c(a,b,c0,c1,c2)       do {    \
320        BN_ULONG ta = (a), tb = (b);            \
321        BN_ULONG lo, hi;                        \
322        BN_UMULT_LOHI(lo,hi,ta,tb);             \
323        c0 += lo; hi += (c0<lo)?1:0;            \
324        c1 += hi; c2 += (c1<hi)?1:0;            \
325        } while(0)
326
327#  define mul_add_c2(a,b,c0,c1,c2)      do {    \
328        BN_ULONG ta = (a), tb = (b);            \
329        BN_ULONG lo, hi, tt;                    \
330        BN_UMULT_LOHI(lo,hi,ta,tb);             \
331        c0 += lo; tt = hi+((c0<lo)?1:0);        \
332        c1 += tt; c2 += (c1<tt)?1:0;            \
333        c0 += lo; hi += (c0<lo)?1:0;            \
334        c1 += hi; c2 += (c1<hi)?1:0;            \
335        } while(0)
336
337#  define sqr_add_c(a,i,c0,c1,c2)       do {    \
338        BN_ULONG ta = (a)[i];                   \
339        BN_ULONG lo, hi;                        \
340        BN_UMULT_LOHI(lo,hi,ta,ta);             \
341        c0 += lo; hi += (c0<lo)?1:0;            \
342        c1 += hi; c2 += (c1<hi)?1:0;            \
343        } while(0)
344# else
345#  define mul_add_c(a,b,c0,c1,c2) do {  \
346        BN_ULONG t1,t2;                 \
347        asm ("mulq %3"                  \
348                : "=a"(t1),"=d"(t2)     \
349                : "a"(a),"m"(b)         \
350                : "cc");                \
351        asm ("addq %3,%0; adcq %4,%1; adcq %5,%2"       \
352                : "+r"(c0),"+r"(c1),"+r"(c2)            \
353                : "r"(t1),"r"(t2),"g"(0)                \
354                : "cc");                                \
355        } while (0)
356
357#  define sqr_add_c(a,i,c0,c1,c2) do {  \
358        BN_ULONG t1,t2;                 \
359        asm ("mulq %2"                  \
360                : "=a"(t1),"=d"(t2)     \
361                : "a"(a[i])             \
362                : "cc");                \
363        asm ("addq %3,%0; adcq %4,%1; adcq %5,%2"       \
364                : "+r"(c0),"+r"(c1),"+r"(c2)            \
365                : "r"(t1),"r"(t2),"g"(0)                \
366                : "cc");                                \
367        } while (0)
368
369#  define mul_add_c2(a,b,c0,c1,c2) do { \
370        BN_ULONG t1,t2;                 \
371        asm ("mulq %3"                  \
372                : "=a"(t1),"=d"(t2)     \
373                : "a"(a),"m"(b)         \
374                : "cc");                \
375        asm ("addq %3,%0; adcq %4,%1; adcq %5,%2"       \
376                : "+r"(c0),"+r"(c1),"+r"(c2)            \
377                : "r"(t1),"r"(t2),"g"(0)                \
378                : "cc");                                \
379        asm ("addq %3,%0; adcq %4,%1; adcq %5,%2"       \
380                : "+r"(c0),"+r"(c1),"+r"(c2)            \
381                : "r"(t1),"r"(t2),"g"(0)                \
382                : "cc");                                \
383        } while (0)
384# endif
385
386# define sqr_add_c2(a,i,j,c0,c1,c2)      \
387        mul_add_c2((a)[i],(a)[j],c0,c1,c2)
388
389void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
390{
391    BN_ULONG c1, c2, c3;
392
393    c1 = 0;
394    c2 = 0;
395    c3 = 0;
396    mul_add_c(a[0], b[0], c1, c2, c3);
397    r[0] = c1;
398    c1 = 0;
399    mul_add_c(a[0], b[1], c2, c3, c1);
400    mul_add_c(a[1], b[0], c2, c3, c1);
401    r[1] = c2;
402    c2 = 0;
403    mul_add_c(a[2], b[0], c3, c1, c2);
404    mul_add_c(a[1], b[1], c3, c1, c2);
405    mul_add_c(a[0], b[2], c3, c1, c2);
406    r[2] = c3;
407    c3 = 0;
408    mul_add_c(a[0], b[3], c1, c2, c3);
409    mul_add_c(a[1], b[2], c1, c2, c3);
410    mul_add_c(a[2], b[1], c1, c2, c3);
411    mul_add_c(a[3], b[0], c1, c2, c3);
412    r[3] = c1;
413    c1 = 0;
414    mul_add_c(a[4], b[0], c2, c3, c1);
415    mul_add_c(a[3], b[1], c2, c3, c1);
416    mul_add_c(a[2], b[2], c2, c3, c1);
417    mul_add_c(a[1], b[3], c2, c3, c1);
418    mul_add_c(a[0], b[4], c2, c3, c1);
419    r[4] = c2;
420    c2 = 0;
421    mul_add_c(a[0], b[5], c3, c1, c2);
422    mul_add_c(a[1], b[4], c3, c1, c2);
423    mul_add_c(a[2], b[3], c3, c1, c2);
424    mul_add_c(a[3], b[2], c3, c1, c2);
425    mul_add_c(a[4], b[1], c3, c1, c2);
426    mul_add_c(a[5], b[0], c3, c1, c2);
427    r[5] = c3;
428    c3 = 0;
429    mul_add_c(a[6], b[0], c1, c2, c3);
430    mul_add_c(a[5], b[1], c1, c2, c3);
431    mul_add_c(a[4], b[2], c1, c2, c3);
432    mul_add_c(a[3], b[3], c1, c2, c3);
433    mul_add_c(a[2], b[4], c1, c2, c3);
434    mul_add_c(a[1], b[5], c1, c2, c3);
435    mul_add_c(a[0], b[6], c1, c2, c3);
436    r[6] = c1;
437    c1 = 0;
438    mul_add_c(a[0], b[7], c2, c3, c1);
439    mul_add_c(a[1], b[6], c2, c3, c1);
440    mul_add_c(a[2], b[5], c2, c3, c1);
441    mul_add_c(a[3], b[4], c2, c3, c1);
442    mul_add_c(a[4], b[3], c2, c3, c1);
443    mul_add_c(a[5], b[2], c2, c3, c1);
444    mul_add_c(a[6], b[1], c2, c3, c1);
445    mul_add_c(a[7], b[0], c2, c3, c1);
446    r[7] = c2;
447    c2 = 0;
448    mul_add_c(a[7], b[1], c3, c1, c2);
449    mul_add_c(a[6], b[2], c3, c1, c2);
450    mul_add_c(a[5], b[3], c3, c1, c2);
451    mul_add_c(a[4], b[4], c3, c1, c2);
452    mul_add_c(a[3], b[5], c3, c1, c2);
453    mul_add_c(a[2], b[6], c3, c1, c2);
454    mul_add_c(a[1], b[7], c3, c1, c2);
455    r[8] = c3;
456    c3 = 0;
457    mul_add_c(a[2], b[7], c1, c2, c3);
458    mul_add_c(a[3], b[6], c1, c2, c3);
459    mul_add_c(a[4], b[5], c1, c2, c3);
460    mul_add_c(a[5], b[4], c1, c2, c3);
461    mul_add_c(a[6], b[3], c1, c2, c3);
462    mul_add_c(a[7], b[2], c1, c2, c3);
463    r[9] = c1;
464    c1 = 0;
465    mul_add_c(a[7], b[3], c2, c3, c1);
466    mul_add_c(a[6], b[4], c2, c3, c1);
467    mul_add_c(a[5], b[5], c2, c3, c1);
468    mul_add_c(a[4], b[6], c2, c3, c1);
469    mul_add_c(a[3], b[7], c2, c3, c1);
470    r[10] = c2;
471    c2 = 0;
472    mul_add_c(a[4], b[7], c3, c1, c2);
473    mul_add_c(a[5], b[6], c3, c1, c2);
474    mul_add_c(a[6], b[5], c3, c1, c2);
475    mul_add_c(a[7], b[4], c3, c1, c2);
476    r[11] = c3;
477    c3 = 0;
478    mul_add_c(a[7], b[5], c1, c2, c3);
479    mul_add_c(a[6], b[6], c1, c2, c3);
480    mul_add_c(a[5], b[7], c1, c2, c3);
481    r[12] = c1;
482    c1 = 0;
483    mul_add_c(a[6], b[7], c2, c3, c1);
484    mul_add_c(a[7], b[6], c2, c3, c1);
485    r[13] = c2;
486    c2 = 0;
487    mul_add_c(a[7], b[7], c3, c1, c2);
488    r[14] = c3;
489    r[15] = c1;
490}
491
492void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
493{
494    BN_ULONG c1, c2, c3;
495
496    c1 = 0;
497    c2 = 0;
498    c3 = 0;
499    mul_add_c(a[0], b[0], c1, c2, c3);
500    r[0] = c1;
501    c1 = 0;
502    mul_add_c(a[0], b[1], c2, c3, c1);
503    mul_add_c(a[1], b[0], c2, c3, c1);
504    r[1] = c2;
505    c2 = 0;
506    mul_add_c(a[2], b[0], c3, c1, c2);
507    mul_add_c(a[1], b[1], c3, c1, c2);
508    mul_add_c(a[0], b[2], c3, c1, c2);
509    r[2] = c3;
510    c3 = 0;
511    mul_add_c(a[0], b[3], c1, c2, c3);
512    mul_add_c(a[1], b[2], c1, c2, c3);
513    mul_add_c(a[2], b[1], c1, c2, c3);
514    mul_add_c(a[3], b[0], c1, c2, c3);
515    r[3] = c1;
516    c1 = 0;
517    mul_add_c(a[3], b[1], c2, c3, c1);
518    mul_add_c(a[2], b[2], c2, c3, c1);
519    mul_add_c(a[1], b[3], c2, c3, c1);
520    r[4] = c2;
521    c2 = 0;
522    mul_add_c(a[2], b[3], c3, c1, c2);
523    mul_add_c(a[3], b[2], c3, c1, c2);
524    r[5] = c3;
525    c3 = 0;
526    mul_add_c(a[3], b[3], c1, c2, c3);
527    r[6] = c1;
528    r[7] = c2;
529}
530
531void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a)
532{
533    BN_ULONG c1, c2, c3;
534
535    c1 = 0;
536    c2 = 0;
537    c3 = 0;
538    sqr_add_c(a, 0, c1, c2, c3);
539    r[0] = c1;
540    c1 = 0;
541    sqr_add_c2(a, 1, 0, c2, c3, c1);
542    r[1] = c2;
543    c2 = 0;
544    sqr_add_c(a, 1, c3, c1, c2);
545    sqr_add_c2(a, 2, 0, c3, c1, c2);
546    r[2] = c3;
547    c3 = 0;
548    sqr_add_c2(a, 3, 0, c1, c2, c3);
549    sqr_add_c2(a, 2, 1, c1, c2, c3);
550    r[3] = c1;
551    c1 = 0;
552    sqr_add_c(a, 2, c2, c3, c1);
553    sqr_add_c2(a, 3, 1, c2, c3, c1);
554    sqr_add_c2(a, 4, 0, c2, c3, c1);
555    r[4] = c2;
556    c2 = 0;
557    sqr_add_c2(a, 5, 0, c3, c1, c2);
558    sqr_add_c2(a, 4, 1, c3, c1, c2);
559    sqr_add_c2(a, 3, 2, c3, c1, c2);
560    r[5] = c3;
561    c3 = 0;
562    sqr_add_c(a, 3, c1, c2, c3);
563    sqr_add_c2(a, 4, 2, c1, c2, c3);
564    sqr_add_c2(a, 5, 1, c1, c2, c3);
565    sqr_add_c2(a, 6, 0, c1, c2, c3);
566    r[6] = c1;
567    c1 = 0;
568    sqr_add_c2(a, 7, 0, c2, c3, c1);
569    sqr_add_c2(a, 6, 1, c2, c3, c1);
570    sqr_add_c2(a, 5, 2, c2, c3, c1);
571    sqr_add_c2(a, 4, 3, c2, c3, c1);
572    r[7] = c2;
573    c2 = 0;
574    sqr_add_c(a, 4, c3, c1, c2);
575    sqr_add_c2(a, 5, 3, c3, c1, c2);
576    sqr_add_c2(a, 6, 2, c3, c1, c2);
577    sqr_add_c2(a, 7, 1, c3, c1, c2);
578    r[8] = c3;
579    c3 = 0;
580    sqr_add_c2(a, 7, 2, c1, c2, c3);
581    sqr_add_c2(a, 6, 3, c1, c2, c3);
582    sqr_add_c2(a, 5, 4, c1, c2, c3);
583    r[9] = c1;
584    c1 = 0;
585    sqr_add_c(a, 5, c2, c3, c1);
586    sqr_add_c2(a, 6, 4, c2, c3, c1);
587    sqr_add_c2(a, 7, 3, c2, c3, c1);
588    r[10] = c2;
589    c2 = 0;
590    sqr_add_c2(a, 7, 4, c3, c1, c2);
591    sqr_add_c2(a, 6, 5, c3, c1, c2);
592    r[11] = c3;
593    c3 = 0;
594    sqr_add_c(a, 6, c1, c2, c3);
595    sqr_add_c2(a, 7, 5, c1, c2, c3);
596    r[12] = c1;
597    c1 = 0;
598    sqr_add_c2(a, 7, 6, c2, c3, c1);
599    r[13] = c2;
600    c2 = 0;
601    sqr_add_c(a, 7, c3, c1, c2);
602    r[14] = c3;
603    r[15] = c1;
604}
605
606void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
607{
608    BN_ULONG c1, c2, c3;
609
610    c1 = 0;
611    c2 = 0;
612    c3 = 0;
613    sqr_add_c(a, 0, c1, c2, c3);
614    r[0] = c1;
615    c1 = 0;
616    sqr_add_c2(a, 1, 0, c2, c3, c1);
617    r[1] = c2;
618    c2 = 0;
619    sqr_add_c(a, 1, c3, c1, c2);
620    sqr_add_c2(a, 2, 0, c3, c1, c2);
621    r[2] = c3;
622    c3 = 0;
623    sqr_add_c2(a, 3, 0, c1, c2, c3);
624    sqr_add_c2(a, 2, 1, c1, c2, c3);
625    r[3] = c1;
626    c1 = 0;
627    sqr_add_c(a, 2, c2, c3, c1);
628    sqr_add_c2(a, 3, 1, c2, c3, c1);
629    r[4] = c2;
630    c2 = 0;
631    sqr_add_c2(a, 3, 2, c3, c1, c2);
632    r[5] = c3;
633    c3 = 0;
634    sqr_add_c(a, 3, c1, c2, c3);
635    r[6] = c1;
636    r[7] = c2;
637}
638#endif
639