1
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
|
/*
* Copyright (c) 2015 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
------------------------------------------------------------------------------
By Bob Jenkins, 1996, Public Domain
MODIFIED:
960327: Creation (addition of randinit, really)
970719: use context, not global variables, for internal state
980324: renamed seed to flag
980605: recommend ISAAC_LOG2_SIZE=4 for noncryptography.
010626: note this is public domain
------------------------------------------------------------------------------
Modified for CLIB by Eliot Dresselhaus.
Dear Bob, Thanks for all the great work. - Eliot
modifications copyright (c) 2003 Eliot Dresselhaus
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.
*/
/* ISAAC is Bob Jenkins' random number generator.
http://burtleburtle.net/bob/rand/isaacafa.html */
#include <vppinfra/random_isaac.h>
#if uword_bits != 32 && uword_bits != 64
#error "isaac only works for 32 or 64 bit words"
#endif
#if uword_bits == 32
#define ind32(mm,x) (*(u32 *)((u8 *)(mm) + ((x) & ((ISAAC_SIZE-1)<<2))))
#define rngstep32(mix,a,b,mm,m,m2,r,x,y) \
{ \
x = *m; \
a = (a^(mix)) + *(m2++); \
*(m++) = y = ind32(mm,x) + a + b; \
*(r++) = b = ind32(mm,y>>ISAAC_LOG2_SIZE) + x; \
}
void
isaac (isaac_t * ctx, uword * results)
{
u32 a, b, c, x, y, *m, *mm, *m2, *r, *mend;
mm = ctx->memory;
r = results;
a = ctx->a;
b = ctx->b;
c = ctx->c;
b += ++c;
mend = m2 = mm + ARRAY_LEN (ctx->memory) / 2;
m = mm;
while (m < mend)
{
rngstep32 (a << 13, a, b, mm, m, m2, r, x, y);
rngstep32 (a >> 6, a, b, mm, m, m2, r, x, y);
rngstep32 (a << 2, a, b, mm, m, m2, r, x, y);
rngstep32 (a >> 16, a, b, mm, m, m2, r, x, y);
}
m2 = mm;
while (m2 < mend)
{
rngstep32 (a << 13, a, b, mm, m, m2, r, x, y);
rngstep32 (a >> 6, a, b, mm, m, m2, r, x, y);
rngstep32 (a << 2, a, b, mm, m, m2, r, x, y);
rngstep32 (a >> 16, a, b, mm, m, m2, r, x, y);
}
ctx->a = a;
ctx->b = b;
ctx->c = c;
}
/* Perform 2 isaac runs with different contexts simultaneously. */
void
isaac2 (isaac_t * ctx, uword * results)
{
#define _(n) \
u32 a##n, b##n, c##n, x##n, y##n, * m##n, * mm##n, * m2##n, * r##n, * mend##n
_(0);
_(1);
(void) mend1; /* "set but unused variable" error on mend1 with gcc 4.9 */
#undef _
#define _(n) \
do { \
mm##n = ctx[(n)].memory; \
r##n = results + (n) * ISAAC_SIZE; \
a##n = ctx[(n)].a; \
b##n = ctx[(n)].b; \
c##n = ctx[(n)].c; \
b##n += ++c##n; \
mend##n = m2##n = mm##n + ARRAY_LEN (ctx[(n)].memory) / 2; \
m##n = mm##n; \
} while (0)
_(0);
_(1);
#undef _
while (m0 < mend0)
{
rngstep32 (a0 << 13, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 << 13, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 >> 6, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 >> 6, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 << 2, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 << 2, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 >> 16, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 >> 16, a1, b1, mm1, m1, m21, r1, x1, y1);
}
m20 = mm0;
m21 = mm1;
while (m20 < mend0)
{
rngstep32 (a0 << 13, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 << 13, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 >> 6, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 >> 6, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 << 2, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 << 2, a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep32 (a0 >> 16, a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep32 (a1 >> 16, a1, b1, mm1, m1, m21, r1, x1, y1);
}
ctx[0].a = a0;
ctx[0].b = b0;
ctx[0].c = c0;
ctx[1].a = a1;
ctx[1].b = b1;
ctx[1].c = c1;
}
#define mix32(a,b,c,d,e,f,g,h) \
{ \
a^=b<<11; d+=a; b+=c; \
b^=c>>2; e+=b; c+=d; \
c^=d<<8; f+=c; d+=e; \
d^=e>>16; g+=d; e+=f; \
e^=f<<10; h+=e; f+=g; \
f^=g>>4; a+=f; g+=h; \
g^=h<<8; b+=g; h+=a; \
h^=a>>9; c+=h; a+=b; \
}
void
isaac_init (isaac_t * ctx, uword * seeds)
{
word i;
u32 a, b, c, d, e, f, g, h, *m, *r;
ctx->a = ctx->b = ctx->c = 0;
m = ctx->memory;
r = seeds;
a = b = c = d = e = f = g = h = 0x9e3779b9; /* the golden ratio */
for (i = 0; i < 4; ++i) /* scramble it */
mix32 (a, b, c, d, e, f, g, h);
/* initialize using the contents of r[] as the seed */
for (i = 0; i < ISAAC_SIZE; i += 8)
{
a += r[i];
b += r[i + 1];
c += r[i + 2];
d += r[i + 3];
e += r[i + 4];
f += r[i + 5];
g += r[i + 6];
h += r[i + 7];
mix32 (a, b, c, d, e, f, g, h);
m[i] = a;
m[i + 1] = b;
m[i + 2] = c;
m[i + 3] = d;
m[i + 4] = e;
m[i + 5] = f;
m[i + 6] = g;
m[i + 7] = h;
}
/* do a second pass to make all of the seed affect all of m */
for (i = 0; i < ISAAC_SIZE; i += 8)
{
a += m[i];
b += m[i + 1];
c += m[i + 2];
d += m[i + 3];
e += m[i + 4];
f += m[i + 5];
g += m[i + 6];
h += m[i + 7];
mix32 (a, b, c, d, e, f, g, h);
m[i] = a;
m[i + 1] = b;
m[i + 2] = c;
m[i + 3] = d;
m[i + 4] = e;
m[i + 5] = f;
m[i + 6] = g;
m[i + 7] = h;
}
}
#endif /* uword_bits == 32 */
#if uword_bits == 64
#define ind64(mm,x) (*(u64 *)((u8 *)(mm) + ((x) & ((ISAAC_SIZE-1)<<3))))
#define rngstep64(mix,a,b,mm,m,m2,r,x,y) \
{ \
x = *m; \
a = (mix) + *(m2++); \
*(m++) = y = ind64(mm,x) + a + b; \
*(r++) = b = ind64(mm,y>>ISAAC_LOG2_SIZE) + x; \
}
void
isaac (isaac_t * ctx, uword * results)
{
u64 a, b, c, x, y, *m, *mm, *m2, *r, *mend;
mm = ctx->memory;
r = results;
a = ctx->a;
b = ctx->b;
c = ctx->c;
b += ++c;
mend = m2 = mm + ARRAY_LEN (ctx->memory) / 2;
m = mm;
while (m < mend)
{
rngstep64 (~(a ^ (a << 21)), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a >> 5), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a << 12), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a >> 33), a, b, mm, m, m2, r, x, y);
}
m2 = mm;
while (m2 < mend)
{
rngstep64 (~(a ^ (a << 21)), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a >> 5), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a << 12), a, b, mm, m, m2, r, x, y);
rngstep64 (a ^ (a >> 33), a, b, mm, m, m2, r, x, y);
}
ctx->a = a;
ctx->b = b;
ctx->c = c;
}
/* Perform 2 isaac runs with different contexts simultaneously. */
void
isaac2 (isaac_t * ctx, uword * results)
{
#define _(n) \
u64 a##n, b##n, c##n, x##n, y##n, * m##n, * mm##n, * m2##n, * r##n, * mend##n
_(0);
_(1);
#undef _
#define _(n) \
do { \
mm##n = ctx[(n)].memory; \
r##n = results + (n) * ISAAC_SIZE; \
a##n = ctx[(n)].a; \
b##n = ctx[(n)].b; \
c##n = ctx[(n)].c; \
b##n += ++c##n; \
mend##n = m2##n = mm##n + ARRAY_LEN (ctx[(n)].memory) / 2; \
m##n = mm##n; \
} while (0)
_(0);
_(1);
#undef _
(void) mend1; /* compiler warning */
while (m0 < mend0)
{
rngstep64 (~(a0 ^ (a0 << 21)), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (~(a1 ^ (a1 << 21)), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 >> 5), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 >> 5), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 << 12), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 << 12), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 >> 33), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 >> 33), a1, b1, mm1, m1, m21, r1, x1, y1);
}
m20 = mm0;
m21 = mm1;
while (m20 < mend0)
{
rngstep64 (~(a0 ^ (a0 << 21)), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (~(a1 ^ (a1 << 21)), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 >> 5), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 >> 5), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 << 12), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 << 12), a1, b1, mm1, m1, m21, r1, x1, y1);
rngstep64 (a0 ^ (a0 >> 33), a0, b0, mm0, m0, m20, r0, x0, y0);
rngstep64 (a1 ^ (a1 >> 33), a1, b1, mm1, m1, m21, r1, x1, y1);
}
ctx[0].a = a0;
ctx[0].b = b0;
ctx[0].c = c0;
ctx[1].a = a1;
ctx[1].b = b1;
ctx[1].c = c1;
}
#define mix64(a,b,c,d,e,f,g,h) \
{ \
a-=e; f^=h>>9; h+=a; \
b-=f; g^=a<<9; a+=b; \
c-=g; h^=b>>23; b+=c; \
d-=h; a^=c<<15; c+=d; \
e-=a; b^=d>>14; d+=e; \
f-=b; c^=e<<20; e+=f; \
g-=c; d^=f>>17; f+=g; \
h-=d; e^=g<<14; g+=h; \
}
void
isaac_init (isaac_t * ctx, uword * seeds)
{
word i;
u64 a, b, c, d, e, f, g, h, *m, *r;
ctx->a = ctx->b = ctx->c = 0;
m = ctx->memory;
r = seeds;
a = b = c = d = e = f = g = h = 0x9e3779b97f4a7c13LL; /* the golden ratio */
for (i = 0; i < 4; ++i) /* scramble it */
mix64 (a, b, c, d, e, f, g, h);
for (i = 0; i < ISAAC_SIZE; i += 8) /* fill in mm[] with messy stuff */
{
a += r[i];
b += r[i + 1];
c += r[i + 2];
d += r[i + 3];
e += r[i + 4];
f += r[i + 5];
g += r[i + 6];
h += r[i + 7];
mix64 (a, b, c, d, e, f, g, h);
m[i] = a;
m[i + 1] = b;
m[i + 2] = c;
m[i + 3] = d;
m[i + 4] = e;
m[i + 5] = f;
m[i + 6] = g;
m[i + 7] = h;
}
/* do a second pass to make all of the seed affect all of mm */
for (i = 0; i < ISAAC_SIZE; i += 8)
{
a += m[i];
b += m[i + 1];
c += m[i + 2];
d += m[i + 3];
e += m[i + 4];
f += m[i + 5];
g += m[i + 6];
h += m[i + 7];
mix64 (a, b, c, d, e, f, g, h);
m[i] = a;
m[i + 1] = b;
m[i + 2] = c;
m[i + 3] = d;
m[i + 4] = e;
m[i + 5] = f;
m[i + 6] = g;
m[i + 7] = h;
}
}
#endif /* uword_bits == 64 */
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
|