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authorGlenn Elliott <gelliott@cs.unc.edu>2012-03-04 19:47:13 -0500
committerGlenn Elliott <gelliott@cs.unc.edu>2012-03-04 19:47:13 -0500
commitc71c03bda1e86c9d5198c5d83f712e695c4f2a1e (patch)
treeecb166cb3e2b7e2adb3b5e292245fefd23381ac8 /arch/x86/lib/memcpy_32.c
parentea53c912f8a86a8567697115b6a0d8152beee5c8 (diff)
parent6a00f206debf8a5c8899055726ad127dbeeed098 (diff)
Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp
Conflicts: litmus/sched_cedf.c
Diffstat (limited to 'arch/x86/lib/memcpy_32.c')
-rw-r--r--arch/x86/lib/memcpy_32.c199
1 files changed, 182 insertions, 17 deletions
diff --git a/arch/x86/lib/memcpy_32.c b/arch/x86/lib/memcpy_32.c
index 5415a9d06f53..b908a59eccf5 100644
--- a/arch/x86/lib/memcpy_32.c
+++ b/arch/x86/lib/memcpy_32.c
@@ -22,22 +22,187 @@ EXPORT_SYMBOL(memset);
22 22
23void *memmove(void *dest, const void *src, size_t n) 23void *memmove(void *dest, const void *src, size_t n)
24{ 24{
25 int d0, d1, d2; 25 int d0,d1,d2,d3,d4,d5;
26 26 char *ret = dest;
27 if (dest < src) { 27
28 memcpy(dest, src, n); 28 __asm__ __volatile__(
29 } else { 29 /* Handle more 16bytes in loop */
30 __asm__ __volatile__( 30 "cmp $0x10, %0\n\t"
31 "std\n\t" 31 "jb 1f\n\t"
32 "rep\n\t" 32
33 "movsb\n\t" 33 /* Decide forward/backward copy mode */
34 "cld" 34 "cmp %2, %1\n\t"
35 : "=&c" (d0), "=&S" (d1), "=&D" (d2) 35 "jb 2f\n\t"
36 :"0" (n), 36
37 "1" (n-1+src), 37 /*
38 "2" (n-1+dest) 38 * movs instruction have many startup latency
39 :"memory"); 39 * so we handle small size by general register.
40 } 40 */
41 return dest; 41 "cmp $680, %0\n\t"
42 "jb 3f\n\t"
43 /*
44 * movs instruction is only good for aligned case.
45 */
46 "mov %1, %3\n\t"
47 "xor %2, %3\n\t"
48 "and $0xff, %3\n\t"
49 "jz 4f\n\t"
50 "3:\n\t"
51 "sub $0x10, %0\n\t"
52
53 /*
54 * We gobble 16byts forward in each loop.
55 */
56 "3:\n\t"
57 "sub $0x10, %0\n\t"
58 "mov 0*4(%1), %3\n\t"
59 "mov 1*4(%1), %4\n\t"
60 "mov %3, 0*4(%2)\n\t"
61 "mov %4, 1*4(%2)\n\t"
62 "mov 2*4(%1), %3\n\t"
63 "mov 3*4(%1), %4\n\t"
64 "mov %3, 2*4(%2)\n\t"
65 "mov %4, 3*4(%2)\n\t"
66 "lea 0x10(%1), %1\n\t"
67 "lea 0x10(%2), %2\n\t"
68 "jae 3b\n\t"
69 "add $0x10, %0\n\t"
70 "jmp 1f\n\t"
71
72 /*
73 * Handle data forward by movs.
74 */
75 ".p2align 4\n\t"
76 "4:\n\t"
77 "mov -4(%1, %0), %3\n\t"
78 "lea -4(%2, %0), %4\n\t"
79 "shr $2, %0\n\t"
80 "rep movsl\n\t"
81 "mov %3, (%4)\n\t"
82 "jmp 11f\n\t"
83 /*
84 * Handle data backward by movs.
85 */
86 ".p2align 4\n\t"
87 "6:\n\t"
88 "mov (%1), %3\n\t"
89 "mov %2, %4\n\t"
90 "lea -4(%1, %0), %1\n\t"
91 "lea -4(%2, %0), %2\n\t"
92 "shr $2, %0\n\t"
93 "std\n\t"
94 "rep movsl\n\t"
95 "mov %3,(%4)\n\t"
96 "cld\n\t"
97 "jmp 11f\n\t"
98
99 /*
100 * Start to prepare for backward copy.
101 */
102 ".p2align 4\n\t"
103 "2:\n\t"
104 "cmp $680, %0\n\t"
105 "jb 5f\n\t"
106 "mov %1, %3\n\t"
107 "xor %2, %3\n\t"
108 "and $0xff, %3\n\t"
109 "jz 6b\n\t"
110
111 /*
112 * Calculate copy position to tail.
113 */
114 "5:\n\t"
115 "add %0, %1\n\t"
116 "add %0, %2\n\t"
117 "sub $0x10, %0\n\t"
118
119 /*
120 * We gobble 16byts backward in each loop.
121 */
122 "7:\n\t"
123 "sub $0x10, %0\n\t"
124
125 "mov -1*4(%1), %3\n\t"
126 "mov -2*4(%1), %4\n\t"
127 "mov %3, -1*4(%2)\n\t"
128 "mov %4, -2*4(%2)\n\t"
129 "mov -3*4(%1), %3\n\t"
130 "mov -4*4(%1), %4\n\t"
131 "mov %3, -3*4(%2)\n\t"
132 "mov %4, -4*4(%2)\n\t"
133 "lea -0x10(%1), %1\n\t"
134 "lea -0x10(%2), %2\n\t"
135 "jae 7b\n\t"
136 /*
137 * Calculate copy position to head.
138 */
139 "add $0x10, %0\n\t"
140 "sub %0, %1\n\t"
141 "sub %0, %2\n\t"
142
143 /*
144 * Move data from 8 bytes to 15 bytes.
145 */
146 ".p2align 4\n\t"
147 "1:\n\t"
148 "cmp $8, %0\n\t"
149 "jb 8f\n\t"
150 "mov 0*4(%1), %3\n\t"
151 "mov 1*4(%1), %4\n\t"
152 "mov -2*4(%1, %0), %5\n\t"
153 "mov -1*4(%1, %0), %1\n\t"
154
155 "mov %3, 0*4(%2)\n\t"
156 "mov %4, 1*4(%2)\n\t"
157 "mov %5, -2*4(%2, %0)\n\t"
158 "mov %1, -1*4(%2, %0)\n\t"
159 "jmp 11f\n\t"
160
161 /*
162 * Move data from 4 bytes to 7 bytes.
163 */
164 ".p2align 4\n\t"
165 "8:\n\t"
166 "cmp $4, %0\n\t"
167 "jb 9f\n\t"
168 "mov 0*4(%1), %3\n\t"
169 "mov -1*4(%1, %0), %4\n\t"
170 "mov %3, 0*4(%2)\n\t"
171 "mov %4, -1*4(%2, %0)\n\t"
172 "jmp 11f\n\t"
173
174 /*
175 * Move data from 2 bytes to 3 bytes.
176 */
177 ".p2align 4\n\t"
178 "9:\n\t"
179 "cmp $2, %0\n\t"
180 "jb 10f\n\t"
181 "movw 0*2(%1), %%dx\n\t"
182 "movw -1*2(%1, %0), %%bx\n\t"
183 "movw %%dx, 0*2(%2)\n\t"
184 "movw %%bx, -1*2(%2, %0)\n\t"
185 "jmp 11f\n\t"
186
187 /*
188 * Move data for 1 byte.
189 */
190 ".p2align 4\n\t"
191 "10:\n\t"
192 "cmp $1, %0\n\t"
193 "jb 11f\n\t"
194 "movb (%1), %%cl\n\t"
195 "movb %%cl, (%2)\n\t"
196 ".p2align 4\n\t"
197 "11:"
198 : "=&c" (d0), "=&S" (d1), "=&D" (d2),
199 "=r" (d3),"=r" (d4), "=r"(d5)
200 :"0" (n),
201 "1" (src),
202 "2" (dest)
203 :"memory");
204
205 return ret;
206
42} 207}
43EXPORT_SYMBOL(memmove); 208EXPORT_SYMBOL(memmove);