1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
|
// file kernel/x/c/shift.c: shift of extensible integers
/*-----------------------------------------------------------------------+
| Copyright 2005-2006, Michel Quercia (michel.quercia@prepas.org) |
| |
| This file is part of Numerix. Numerix is free software; you can |
| redistribute it and/or modify it under the terms of the GNU Lesser |
| General Public License as published by the Free Software Foundation; |
| either version 2.1 of the License, or (at your option) any later |
| version. |
| |
| The Numerix Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU MP Library; see the file COPYING. If not, |
| write to the Free Software Foundation, Inc., 59 Temple Place - |
| Suite 330, Boston, MA 02111-1307, USA. |
+-----------------------------------------------------------------------+
| |
| Dcalages |
| |
+-----------------------------------------------------------------------*/
/* +-------------+
| Dcalages |
+-------------+ */
/*
entre :
a = entier extensible
_b = NULL ou pointeur sur un entier extensible
n = entier non sign
sens = 0 ou 1
sortie :
si sens = 0: b <- a >> n
si sens = 1: b <- a << n
si _b != NULL, *_b <- b
retourne b
*/
xint xx(private_shift)(xint *_b, xint a, unsigned long n, long sens) {
long la = xx_lg(a), sa = xx_sgn(a), lb,p;
chiffre r;
xint b;
xx_push_roots_2(a,_b);
#ifdef caml_api
#define a __lr.a
#define _b __lr._b
#endif
/* a = 0 ou n = 0 => b <- a */
if ((la == 0) || (n == 0)) {
b = xx(enlarge)(_b,la);
if (a != b) {xn(move)(a->val,la,b->val); b->hd = a->hd;}
}
else if (sens) { /* --------------- dcalage gauche */
p = (n + HW-1)/HW; n = p*HW - n;
lb = la + p;
b = xx(enlarge)(_b,lb);
/* bug potentiel sur x86 : si n = 0, r << (HW-n) = r (dcalage non effectu).
En fait a ne gne pas car on a r = 0 dans ce cas. */
r = xn(shift_down)(a->val,la,b->val+p,n);
b->val[p-1] = r << (HW-n);
xn(clear)(b->val,p-1);
xx(make_head)(b,lb,sa);
}
else { /* ------------------------- dcalage droite */
p = (n + HW-1)/HW; n = p*HW - n;
lb = la - p + 1;
if (lb <= 0) {b = xx(enlarge)(_b,0); b->hd = 0;}
else {
b = xx(enlarge)(_b,lb);
r = (n) ? a->val[p-1] >> (HW-n) : 0;
if (p < la) {
b->val[lb-1] = xn(shift_up)(a->val+p,la-p,b->val,n);
b->val[0] |= r;
}
else b->val[0] = r;
xx(make_head)(b,lb,sa);
}
}
xx_update_and_return(_b,b);
#undef a
#undef _b
}
#if defined(caml_api) || defined(ocaml_api)
xint xx(shl)(xint *_b, xint a, long n) {
return((n >= 0) ? xx(private_shift)(_b,a, Long_val(n),1) :
xx(private_shift)(_b,a,-Long_val(n),0));
}
xint xx(shr)(xint *_b, xint a, long n) {
return((n < 0) ? xx(private_shift)(_b,a,-Long_val(n),1) :
xx(private_shift)(_b,a, Long_val(n),0));
}
xint xx(f_shl)(xint a, long n) {
return((n >= 0) ? xx(private_shift)(xx_null,a, Long_val(n),1) :
xx(private_shift)(xx_null,a,-Long_val(n),0));
}
xint xx(f_shr)(xint a, long n) {
return((n < 0) ? xx(private_shift)(xx_null,a,-Long_val(n),1) :
xx(private_shift)(xx_null,a, Long_val(n),0));
}
#endif /* api */
/* +-------------+
| Dcoupage |
+-------------+ */
/*
entre :
a = entier extensible
_b,_c = NULL ou pointeurs vers des entiers extensibles
n = longueur >= 0
contraintes :
en mode Caml/Ocaml, _b et _c ont la mme validit (NULL/non NULL)
en mode C, les validits de _b et _c sont indpendantes
lorsque _b et _c sont des pointeurs valides, ils sont distincts
sortie :
b <- sgn(a)*floor(|a|/2^n)
c <- sgn(a)*(|a| mod 2^n)
si_ b != NULL, *_b <- b
si _c != NULL, *_c <- c
si _b = _c = NULL retourne le couple (b,c) (Caml/Ocaml uniquement)
erreur :
NEGATIVE_INDEX si n < 0
MULTIPLE_RESULT si _b == _c != NULL
*/
#if defined(c_api)
void
#elif defined(caml_api) || defined(ocaml_api)
value
#endif
xx(split)(xint *_b, xint *_c, xint a, long n) {
long la = xx_lg(a), sa = xx_sgn(a), lb,lc,p;
chiffre r;
xx_push_roots_32(a,_b,_c,b,c);
#ifdef caml_api
#define a __lr.a
#define b __lr.b
#define c __lr.c
#define _b __lr._b
#define _c __lr._c
#endif
#if defined(caml_api) || defined(ocaml_api)
n = Long_val(n);
#endif
/* contrle les arguments
L'identit des validits de _b et _c n'est pas vrifie car elle
est garantie par les fonctions appelantes en mode Caml/Ocaml.
*/
if (n < 0) xx(failwith)(NEGATIVE_INDEX);
if (_b == _c) {
if (_c != xx_null) xx(failwith)(MULTIPLE_RESULT);
#ifdef c_api
else return;
#endif
}
/* traite les cas a = 0 et n = 0 part */
if ((la == 0) || (n == 0)) {
b = xx(enlarge)(_b,la);
if (a != b) {xn(move)(a->val,la,b->val); b->hd = a->hd;}
c = xx(enlarge)(_c,0);
c->hd = 0;
}
else {
/* taille des rsultats */
p = (n + HW-1)/HW; n = p*HW - n;
lb = la - p + 1; if (lb < 0) lb = 0;
lc = p; if (lc > la) lc = la;
b = xx(enlarge)(_b,lb);
c = xx(enlarge)(_c,lc);
/* copie les parties basse et haute de a dans b et c */
if (a != c) xn(move)(a->val,lc,c->val);
if (lb) {
r = (n) ? a->val[p-1] >> (HW-n) : 0;
if (p < la) {
b->val[lb-1] = xn(shift_up)(a->val+p,la-p,b->val,n);
b->val[0] |= r;
}
else b->val[0] = r;
}
if ((lc == p) && (n)) c->val[p-1] &= (((chiffre)1<<(HW-n)) - 1);
/* signe et longueurs effectives */
xx(make_head)(b,lb,sa);
xx(make_head)(c,lc,sa);
}
/* mise jour des pointeurs _b et _c ou retour du couple (b,c) */
#if defined(c_api)
(_b == xx_null) ? xx(remove)(&b) : xx(update)(_b,b);
(_c == xx_null) ? xx(remove)(&c) : xx(update)(_c,c);
return;
#elif defined(caml_api) || defined(ocaml_api)
if (_b != xx_null) {
if (*_b != b) modify((value *)_b,(value)b);
if (*_c != c) modify((value *)_c,(value)c);
xx_pop_roots();
return(Val_unit);
} else {
xint *r = (xint *)alloc_tuple(2);
r[0] = b;
r[1] = c;
xx_pop_roots();
return((value)r);
}
#endif /* api */
#undef a
#undef b
#undef c
#undef _b
#undef _c
}
#if defined(caml_api) || defined(ocaml_api)
value xx(f_split)(xint a, long n) {return(xx(split)(xx_null,xx_null,a,n));}
#endif /* defined(caml_api) || defined(ocaml_api) */
/* +-----------------+
| Concatnation |
+-----------------+ */
/*
entre :
a,b = entiers extensibles
_c = NULL ou pointeur sur un entier extensible
n = longueur >= 0
sortie :
c <- a + b*2^n
si _c != NULL, *_c <- c
retourne c
erreur :
NEGATIVE_INDEX si n < 0
*/
xint xx(join)(xint *_c, xint a, xint b, long n) {
long la = xx_lg(a), lb = xx_lg(b), lc;
long sa = xx_sgn(a), sb = xx_sgn(b);
long p;
chiffre *aa,r;
int free_a;
xint c;
xx_push_roots_3(a,b,_c);
#ifdef caml_api
#define a __lr.a
#define b __lr.b
#define _c __lr._c
#endif
#if defined(caml_api) || defined(ocaml_api)
n = Long_val(n);
#endif
if (n < 0) xx(failwith)(NEGATIVE_INDEX);
/* traite le cas b = 0 part */
if (lb == 0) {
c = xx(enlarge)(_c,la);
if (a != c) {xn(move)(a->val,la,c->val); c->hd = a->hd;}
xx_update_and_return(_c,c);
}
/* taille du rsultat */
p = (n + HW-1)/HW; n = p*HW - n;
lc = lb + p;
if (lc <= la) lc = la;
if (sa == sb) lc++;
c = xx(enlarge)(_c,lc);
/* si a va tre cras, le recopie */
if (a == c) {
aa = xn(alloc)(la);
xn(move)(c->val,la,aa);
free_a = 1;
} else {aa = a->val, free_a = 0;}
/* c <- b*2^n */
r = xn(shift_down)(b->val,lb,c->val+p,n);
if (p) {c->val[p-1] = r << (HW-n); xn(clear)(c->val,p-1);}
xn(clear)(c->val+lb+p, lc-lb-p);
/* c <- c + a */
if (sa == sb) xn(inc)(c->val,lc,aa,la);
else if (xn(cmp)(c->val,lc,aa,la) >= 0) xn(dec)(c->val,lc,aa,la);
else {sb = sa; xn(sub)(aa,la,c->val,la,c->val);}
/* libre a s'il a t recopi */
if (free_a) xn(free)(aa);
/* taille et signe du rsultat */
xx(make_head)(c,lc,sb);
xx_update_and_return(_c,c);
#undef a
#undef b
#undef _c
}
#if defined(caml_api) || defined(ocaml_api)
xint xx(f_join)(xint a, xint b, long n) {return xx(join)(xx_null,a,b,n);}
#endif /* defined(caml_api) || defined(ocaml_api) */
|
