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-rw-r--r--arch/arm/lib/udivdi3.c372
1 files changed, 176 insertions, 196 deletions
diff --git a/arch/arm/lib/udivdi3.c b/arch/arm/lib/udivdi3.c
index df1d5ef62bc7..e343be4c6642 100644
--- a/arch/arm/lib/udivdi3.c
+++ b/arch/arm/lib/udivdi3.c
@@ -32,211 +32,191 @@ Boston, MA 02111-1307, USA. */
32#include "gcclib.h" 32#include "gcclib.h"
33#include "longlong.h" 33#include "longlong.h"
34 34
35static const u8 __clz_tab[] = 35static const u8 __clz_tab[] = {
36{ 36 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5,
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, 37 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, 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,
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, 39 6, 6, 6, 6, 6, 6, 6, 6,
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, 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,
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, 41 7, 7, 7, 7, 7, 7, 7, 7,
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, 42 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
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, 43 7, 7, 7, 7, 7, 7, 7, 7,
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, 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,
45 8, 8, 8, 8, 8, 8, 8, 8,
46 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
47 8, 8, 8, 8, 8, 8, 8, 8,
48 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
49 8, 8, 8, 8, 8, 8, 8, 8,
50 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
51 8, 8, 8, 8, 8, 8, 8, 8,
45}; 52};
46 53
47u64 54u64 __udivmoddi4(u64 n, u64 d, u64 * rp)
48__udivmoddi4 (u64 n, u64 d, u64 *rp)
49{ 55{
50 DIunion ww; 56 DIunion ww;
51 DIunion nn, dd; 57 DIunion nn, dd;
52 DIunion rr; 58 DIunion rr;
53 u32 d0, d1, n0, n1, n2; 59 u32 d0, d1, n0, n1, n2;
54 u32 q0, q1; 60 u32 q0, q1;
55 u32 b, bm; 61 u32 b, bm;
56 62
57 nn.ll = n; 63 nn.ll = n;
58 dd.ll = d; 64 dd.ll = d;
59 65
60 d0 = dd.s.low; 66 d0 = dd.s.low;
61 d1 = dd.s.high; 67 d1 = dd.s.high;
62 n0 = nn.s.low; 68 n0 = nn.s.low;
63 n1 = nn.s.high; 69 n1 = nn.s.high;
64 70
65 if (d1 == 0) 71 if (d1 == 0) {
66 { 72 if (d0 > n1) {
67 if (d0 > n1) 73 /* 0q = nn / 0D */
68 { 74
69 /* 0q = nn / 0D */ 75 count_leading_zeros(bm, d0);
70 76
71 count_leading_zeros (bm, d0); 77 if (bm != 0) {
72 78 /* Normalize, i.e. make the most significant bit of the
73 if (bm != 0) 79 denominator set. */
74 { 80
75 /* Normalize, i.e. make the most significant bit of the 81 d0 = d0 << bm;
76 denominator set. */ 82 n1 = (n1 << bm) | (n0 >> (SI_TYPE_SIZE - bm));
77 83 n0 = n0 << bm;
78 d0 = d0 << bm; 84 }
79 n1 = (n1 << bm) | (n0 >> (SI_TYPE_SIZE - bm)); 85
80 n0 = n0 << bm; 86 udiv_qrnnd(q0, n0, n1, n0, d0);
81 } 87 q1 = 0;
82 88
83 udiv_qrnnd (q0, n0, n1, n0, d0); 89 /* Remainder in n0 >> bm. */
84 q1 = 0; 90 } else {
85 91 /* qq = NN / 0d */
86 /* Remainder in n0 >> bm. */ 92
87 } 93 if (d0 == 0)
88 else 94 d0 = 1 / d0; /* Divide intentionally by zero. */
89 { 95
90 /* qq = NN / 0d */ 96 count_leading_zeros(bm, d0);
91 97
92 if (d0 == 0) 98 if (bm == 0) {
93 d0 = 1 / d0; /* Divide intentionally by zero. */ 99 /* From (n1 >= d0) /\ (the most significant bit of d0 is set),
94 100 conclude (the most significant bit of n1 is set) /\ (the
95 count_leading_zeros (bm, d0); 101 leading quotient digit q1 = 1).
96 102
97 if (bm == 0) 103 This special case is necessary, not an optimization.
98 { 104 (Shifts counts of SI_TYPE_SIZE are undefined.) */
99 /* From (n1 >= d0) /\ (the most significant bit of d0 is set), 105
100 conclude (the most significant bit of n1 is set) /\ (the 106 n1 -= d0;
101 leading quotient digit q1 = 1). 107 q1 = 1;
102 108 } else {
103 This special case is necessary, not an optimization. 109 /* Normalize. */
104 (Shifts counts of SI_TYPE_SIZE are undefined.) */ 110
105 111 b = SI_TYPE_SIZE - bm;
106 n1 -= d0; 112
107 q1 = 1; 113 d0 = d0 << bm;
108 } 114 n2 = n1 >> b;
109 else 115 n1 = (n1 << bm) | (n0 >> b);
110 { 116 n0 = n0 << bm;
111 /* Normalize. */ 117
112 118 udiv_qrnnd(q1, n1, n2, n1, d0);
113 b = SI_TYPE_SIZE - bm; 119 }
114 120
115 d0 = d0 << bm; 121 /* n1 != d0... */
116 n2 = n1 >> b; 122
117 n1 = (n1 << bm) | (n0 >> b); 123 udiv_qrnnd(q0, n0, n1, n0, d0);
118 n0 = n0 << bm; 124
119 125 /* Remainder in n0 >> bm. */
120 udiv_qrnnd (q1, n1, n2, n1, d0); 126 }
121 } 127
122 128 if (rp != 0) {
123 /* n1 != d0... */ 129 rr.s.low = n0 >> bm;
124 130 rr.s.high = 0;
125 udiv_qrnnd (q0, n0, n1, n0, d0); 131 *rp = rr.ll;
126 132 }
127 /* Remainder in n0 >> bm. */ 133 } else {
128 } 134 if (d1 > n1) {
129 135 /* 00 = nn / DD */
130 if (rp != 0) 136
131 { 137 q0 = 0;
132 rr.s.low = n0 >> bm; 138 q1 = 0;
133 rr.s.high = 0; 139
134 *rp = rr.ll; 140 /* Remainder in n1n0. */
135 } 141 if (rp != 0) {
136 } 142 rr.s.low = n0;
137 else 143 rr.s.high = n1;
138 { 144 *rp = rr.ll;
139 if (d1 > n1) 145 }
140 { 146 } else {
141 /* 00 = nn / DD */ 147 /* 0q = NN / dd */
142 148
143 q0 = 0; 149 count_leading_zeros(bm, d1);
144 q1 = 0; 150 if (bm == 0) {
145 151 /* From (n1 >= d1) /\ (the most significant bit of d1 is set),
146 /* Remainder in n1n0. */ 152 conclude (the most significant bit of n1 is set) /\ (the
147 if (rp != 0) 153 quotient digit q0 = 0 or 1).
148 { 154
149 rr.s.low = n0; 155 This special case is necessary, not an optimization. */
150 rr.s.high = n1; 156
151 *rp = rr.ll; 157 /* The condition on the next line takes advantage of that
152 } 158 n1 >= d1 (true due to program flow). */
153 } 159 if (n1 > d1 || n0 >= d0) {
154 else 160 q0 = 1;
155 { 161 sub_ddmmss(n1, n0, n1, n0, d1, d0);
156 /* 0q = NN / dd */ 162 } else
157 163 q0 = 0;
158 count_leading_zeros (bm, d1); 164
159 if (bm == 0) 165 q1 = 0;
160 { 166
161 /* From (n1 >= d1) /\ (the most significant bit of d1 is set), 167 if (rp != 0) {
162 conclude (the most significant bit of n1 is set) /\ (the 168 rr.s.low = n0;
163 quotient digit q0 = 0 or 1). 169 rr.s.high = n1;
164 170 *rp = rr.ll;
165 This special case is necessary, not an optimization. */ 171 }
166 172 } else {
167 /* The condition on the next line takes advantage of that 173 u32 m1, m0;
168 n1 >= d1 (true due to program flow). */ 174 /* Normalize. */
169 if (n1 > d1 || n0 >= d0) 175
170 { 176 b = SI_TYPE_SIZE - bm;
171 q0 = 1; 177
172 sub_ddmmss (n1, n0, n1, n0, d1, d0); 178 d1 = (d1 << bm) | (d0 >> b);
173 } 179 d0 = d0 << bm;
174 else 180 n2 = n1 >> b;
175 q0 = 0; 181 n1 = (n1 << bm) | (n0 >> b);
176 182 n0 = n0 << bm;
177 q1 = 0; 183
178 184 udiv_qrnnd(q0, n1, n2, n1, d1);
179 if (rp != 0) 185 umul_ppmm(m1, m0, q0, d0);
180 { 186
181 rr.s.low = n0; 187 if (m1 > n1 || (m1 == n1 && m0 > n0)) {
182 rr.s.high = n1; 188 q0--;
183 *rp = rr.ll; 189 sub_ddmmss(m1, m0, m1, m0, d1, d0);
184 } 190 }
185 } 191
186 else 192 q1 = 0;
187 { 193
188 u32 m1, m0; 194 /* Remainder in (n1n0 - m1m0) >> bm. */
189 /* Normalize. */ 195 if (rp != 0) {
190 196 sub_ddmmss(n1, n0, n1, n0, m1, m0);
191 b = SI_TYPE_SIZE - bm; 197 rr.s.low = (n1 << b) | (n0 >> bm);
192 198 rr.s.high = n1 >> bm;
193 d1 = (d1 << bm) | (d0 >> b); 199 *rp = rr.ll;
194 d0 = d0 << bm; 200 }
195 n2 = n1 >> b; 201 }
196 n1 = (n1 << bm) | (n0 >> b); 202 }
197 n0 = n0 << bm; 203 }
198 204
199 udiv_qrnnd (q0, n1, n2, n1, d1); 205 ww.s.low = q0;
200 umul_ppmm (m1, m0, q0, d0); 206 ww.s.high = q1;
201 207 return ww.ll;
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} 208}
226 209
227u64 210u64 __udivdi3(u64 n, u64 d)
228__udivdi3 (u64 n, u64 d)
229{ 211{
230 return __udivmoddi4 (n, d, (u64 *) 0); 212 return __udivmoddi4(n, d, (u64 *) 0);
231} 213}
232 214
233u64 215u64 __umoddi3(u64 u, u64 v)
234__umoddi3 (u64 u, u64 v)
235{ 216{
236 u64 w; 217 u64 w;
237 218
238 (void) __udivmoddi4 (u ,v, &w); 219 (void)__udivmoddi4(u, v, &w);
239 220
240 return w; 221 return w;
241} 222}
242
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