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Linux-2.6.12-rc2
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / arm26 / lib / udivdi3.c
CommitLineData
1da177e4
LT		 1/* More subroutines needed by GCC output code on some machines. */
2/* Compile this one with gcc. */
3/* Copyright (C) 1989, 92-98, 1999 Free Software Foundation, Inc.
4
5This file is part of GNU CC.
6
7GNU CC is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
11
12GNU CC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU CC; see the file COPYING. If not, write to
19the Free Software Foundation, 59 Temple Place - Suite 330,
20Boston, MA 02111-1307, USA. */
21
22/* As a special exception, if you link this library with other files,
23 some of which are compiled with GCC, to produce an executable,
24 this library does not by itself cause the resulting executable
25 to be covered by the GNU General Public License.
26 This exception does not however invalidate any other reasons why
27 the executable file might be covered by the GNU General Public License.
28 */
29/* support functions required by the kernel. based on code from gcc-2.95.3 */
30/* I Molton 29/07/01 */
31
32#include "gcclib.h"
33#include "longlong.h"
34
35static const UQItype __clz_tab[] =
36{
37 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
38 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
39 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
40 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
41 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
42 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
43 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
44 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
45};
46
47UDItype
48__udivmoddi4 (UDItype n, UDItype d, UDItype *rp)
49{
50 DIunion ww;
51 DIunion nn, dd;
52 DIunion rr;
53 USItype d0, d1, n0, n1, n2;
54 USItype q0, q1;
55 USItype b, bm;
56
57 nn.ll = n;
58 dd.ll = d;
59
60 d0 = dd.s.low;
61 d1 = dd.s.high;
62 n0 = nn.s.low;
63 n1 = nn.s.high;
64
65 if (d1 == 0)
66 {
67 if (d0 > n1)
68 {
69 /* 0q = nn / 0D */
70
71 count_leading_zeros (bm, d0);
72
73 if (bm != 0)
74 {
75 /* Normalize, i.e. make the most significant bit of the
76 denominator set. */
77
78 d0 = d0 << bm;
79 n1 = (n1 << bm) | (n0 >> (SI_TYPE_SIZE - bm));
80 n0 = n0 << bm;
81 }
82
83 udiv_qrnnd (q0, n0, n1, n0, d0);
84 q1 = 0;
85
86 /* Remainder in n0 >> bm. */
87 }
88 else
89 {
90 /* qq = NN / 0d */
91
92 if (d0 == 0)
93 d0 = 1 / d0; /* Divide intentionally by zero. */
94
95 count_leading_zeros (bm, d0);
96
97 if (bm == 0)
98 {
99 /* From (n1 >= d0) /\ (the most significant bit of d0 is set),
100 conclude (the most significant bit of n1 is set) /\ (the
101 leading quotient digit q1 = 1).
102
103 This special case is necessary, not an optimization.
104 (Shifts counts of SI_TYPE_SIZE are undefined.) */
105
106 n1 -= d0;
107 q1 = 1;
108 }
109 else
110 {
111 /* Normalize. */
112
113 b = SI_TYPE_SIZE - bm;
114
115 d0 = d0 << bm;
116 n2 = n1 >> b;
117 n1 = (n1 << bm) | (n0 >> b);
118 n0 = n0 << bm;
119
120 udiv_qrnnd (q1, n1, n2, n1, d0);
121 }
122
123 /* n1 != d0... */
124
125 udiv_qrnnd (q0, n0, n1, n0, d0);
126
127 /* Remainder in n0 >> bm. */
128 }
129
130 if (rp != 0)
131 {
132 rr.s.low = n0 >> bm;
133 rr.s.high = 0;
134 *rp = rr.ll;
135 }
136 }
137 else
138 {
139 if (d1 > n1)
140 {
141 /* 00 = nn / DD */
142
143 q0 = 0;
144 q1 = 0;
145
146 /* Remainder in n1n0. */
147 if (rp != 0)
148 {
149 rr.s.low = n0;
150 rr.s.high = n1;
151 *rp = rr.ll;
152 }
153 }
154 else
155 {
156 /* 0q = NN / dd */
157
158 count_leading_zeros (bm, d1);
159 if (bm == 0)
160 {
161 /* From (n1 >= d1) /\ (the most significant bit of d1 is set),
162 conclude (the most significant bit of n1 is set) /\ (the
163 quotient digit q0 = 0 or 1).
164
165 This special case is necessary, not an optimization. */
166
167 /* The condition on the next line takes advantage of that
168 n1 >= d1 (true due to program flow). */
169 if (n1 > d1 || n0 >= d0)
170 {
171 q0 = 1;
172 sub_ddmmss (n1, n0, n1, n0, d1, d0);
173 }
174 else
175 q0 = 0;
176
177 q1 = 0;
178
179 if (rp != 0)
180 {
181 rr.s.low = n0;
182 rr.s.high = n1;
183 *rp = rr.ll;
184 }
185 }
186 else
187 {
188 USItype m1, m0;
189 /* Normalize. */
190
191 b = SI_TYPE_SIZE - bm;
192
193 d1 = (d1 << bm) | (d0 >> b);
194 d0 = d0 << bm;
195 n2 = n1 >> b;
196 n1 = (n1 << bm) | (n0 >> b);
197 n0 = n0 << bm;
198
199 udiv_qrnnd (q0, n1, n2, n1, d1);
200 umul_ppmm (m1, m0, q0, d0);
201
202 if (m1 > n1 || (m1 == n1 && m0 > n0))
203 {
204 q0--;
205 sub_ddmmss (m1, m0, m1, m0, d1, d0);
206 }
207
208 q1 = 0;
209
210 /* Remainder in (n1n0 - m1m0) >> bm. */
211 if (rp != 0)
212 {
213 sub_ddmmss (n1, n0, n1, n0, m1, m0);
214 rr.s.low = (n1 << b) | (n0 >> bm);
215 rr.s.high = n1 >> bm;
216 *rp = rr.ll;
217 }
218 }
219 }
220 }
221
222 ww.s.low = q0;
223 ww.s.high = q1;
224 return ww.ll;
225}
226
227UDItype
228__udivdi3 (UDItype n, UDItype d)
229{
230 return __udivmoddi4 (n, d, (UDItype *) 0);
231}
232
233UDItype
234__umoddi3 (UDItype u, UDItype v)
235{
236 UDItype w;
237
238 (void) __udivmoddi4 (u ,v, &w);
239
240 return w;
241}
242
kernel source for telekom puls (alcatel/mediatek)