Matthias Weisser | 93416c1 | 2011-03-10 21:36:32 +0000 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/lib/memcpy.S |
| 3 | * |
| 4 | * Author: Nicolas Pitre |
| 5 | * Created: Sep 28, 2005 |
| 6 | * Copyright: MontaVista Software, Inc. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | */ |
| 12 | |
| 13 | #include <asm/assembler.h> |
| 14 | |
| 15 | #define W(instr) instr |
| 16 | |
| 17 | #define LDR1W_SHIFT 0 |
| 18 | #define STR1W_SHIFT 0 |
| 19 | |
| 20 | .macro ldr1w ptr reg abort |
| 21 | W(ldr) \reg, [\ptr], #4 |
| 22 | .endm |
| 23 | |
| 24 | .macro ldr4w ptr reg1 reg2 reg3 reg4 abort |
| 25 | ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4} |
| 26 | .endm |
| 27 | |
| 28 | .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort |
| 29 | ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} |
| 30 | .endm |
| 31 | |
| 32 | .macro ldr1b ptr reg cond=al abort |
| 33 | ldr\cond\()b \reg, [\ptr], #1 |
| 34 | .endm |
| 35 | |
| 36 | .macro str1w ptr reg abort |
| 37 | W(str) \reg, [\ptr], #4 |
| 38 | .endm |
| 39 | |
| 40 | .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort |
| 41 | stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} |
| 42 | .endm |
| 43 | |
| 44 | .macro str1b ptr reg cond=al abort |
| 45 | str\cond\()b \reg, [\ptr], #1 |
| 46 | .endm |
| 47 | |
| 48 | .macro enter reg1 reg2 |
| 49 | stmdb sp!, {r0, \reg1, \reg2} |
| 50 | .endm |
| 51 | |
| 52 | .macro exit reg1 reg2 |
| 53 | ldmfd sp!, {r0, \reg1, \reg2} |
| 54 | .endm |
| 55 | |
| 56 | .text |
| 57 | |
| 58 | /* Prototype: void *memcpy(void *dest, const void *src, size_t n); */ |
| 59 | |
| 60 | .globl memcpy |
| 61 | memcpy: |
| 62 | |
| 63 | enter r4, lr |
| 64 | |
| 65 | subs r2, r2, #4 |
| 66 | blt 8f |
| 67 | ands ip, r0, #3 |
| 68 | PLD( pld [r1, #0] ) |
| 69 | bne 9f |
| 70 | ands ip, r1, #3 |
| 71 | bne 10f |
| 72 | |
| 73 | 1: subs r2, r2, #(28) |
| 74 | stmfd sp!, {r5 - r8} |
| 75 | blt 5f |
| 76 | |
| 77 | CALGN( ands ip, r0, #31 ) |
| 78 | CALGN( rsb r3, ip, #32 ) |
| 79 | CALGN( sbcnes r4, r3, r2 ) @ C is always set here |
| 80 | CALGN( bcs 2f ) |
| 81 | CALGN( adr r4, 6f ) |
| 82 | CALGN( subs r2, r2, r3 ) @ C gets set |
| 83 | CALGN( add pc, r4, ip ) |
| 84 | |
| 85 | PLD( pld [r1, #0] ) |
| 86 | 2: PLD( subs r2, r2, #96 ) |
| 87 | PLD( pld [r1, #28] ) |
| 88 | PLD( blt 4f ) |
| 89 | PLD( pld [r1, #60] ) |
| 90 | PLD( pld [r1, #92] ) |
| 91 | |
| 92 | 3: PLD( pld [r1, #124] ) |
| 93 | 4: ldr8w r1, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f |
| 94 | subs r2, r2, #32 |
| 95 | str8w r0, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f |
| 96 | bge 3b |
| 97 | PLD( cmn r2, #96 ) |
| 98 | PLD( bge 4b ) |
| 99 | |
| 100 | 5: ands ip, r2, #28 |
| 101 | rsb ip, ip, #32 |
| 102 | #if LDR1W_SHIFT > 0 |
| 103 | lsl ip, ip, #LDR1W_SHIFT |
| 104 | #endif |
| 105 | addne pc, pc, ip @ C is always clear here |
| 106 | b 7f |
| 107 | 6: |
| 108 | .rept (1 << LDR1W_SHIFT) |
| 109 | W(nop) |
| 110 | .endr |
| 111 | ldr1w r1, r3, abort=20f |
| 112 | ldr1w r1, r4, abort=20f |
| 113 | ldr1w r1, r5, abort=20f |
| 114 | ldr1w r1, r6, abort=20f |
| 115 | ldr1w r1, r7, abort=20f |
| 116 | ldr1w r1, r8, abort=20f |
| 117 | ldr1w r1, lr, abort=20f |
| 118 | |
| 119 | #if LDR1W_SHIFT < STR1W_SHIFT |
| 120 | lsl ip, ip, #STR1W_SHIFT - LDR1W_SHIFT |
| 121 | #elif LDR1W_SHIFT > STR1W_SHIFT |
| 122 | lsr ip, ip, #LDR1W_SHIFT - STR1W_SHIFT |
| 123 | #endif |
| 124 | add pc, pc, ip |
| 125 | nop |
| 126 | .rept (1 << STR1W_SHIFT) |
| 127 | W(nop) |
| 128 | .endr |
| 129 | str1w r0, r3, abort=20f |
| 130 | str1w r0, r4, abort=20f |
| 131 | str1w r0, r5, abort=20f |
| 132 | str1w r0, r6, abort=20f |
| 133 | str1w r0, r7, abort=20f |
| 134 | str1w r0, r8, abort=20f |
| 135 | str1w r0, lr, abort=20f |
| 136 | |
| 137 | CALGN( bcs 2b ) |
| 138 | |
| 139 | 7: ldmfd sp!, {r5 - r8} |
| 140 | |
| 141 | 8: movs r2, r2, lsl #31 |
| 142 | ldr1b r1, r3, ne, abort=21f |
| 143 | ldr1b r1, r4, cs, abort=21f |
| 144 | ldr1b r1, ip, cs, abort=21f |
| 145 | str1b r0, r3, ne, abort=21f |
| 146 | str1b r0, r4, cs, abort=21f |
| 147 | str1b r0, ip, cs, abort=21f |
| 148 | |
| 149 | exit r4, pc |
| 150 | |
| 151 | 9: rsb ip, ip, #4 |
| 152 | cmp ip, #2 |
| 153 | ldr1b r1, r3, gt, abort=21f |
| 154 | ldr1b r1, r4, ge, abort=21f |
| 155 | ldr1b r1, lr, abort=21f |
| 156 | str1b r0, r3, gt, abort=21f |
| 157 | str1b r0, r4, ge, abort=21f |
| 158 | subs r2, r2, ip |
| 159 | str1b r0, lr, abort=21f |
| 160 | blt 8b |
| 161 | ands ip, r1, #3 |
| 162 | beq 1b |
| 163 | |
| 164 | 10: bic r1, r1, #3 |
| 165 | cmp ip, #2 |
| 166 | ldr1w r1, lr, abort=21f |
| 167 | beq 17f |
| 168 | bgt 18f |
| 169 | |
| 170 | |
| 171 | .macro forward_copy_shift pull push |
| 172 | |
| 173 | subs r2, r2, #28 |
| 174 | blt 14f |
| 175 | |
| 176 | CALGN( ands ip, r0, #31 ) |
| 177 | CALGN( rsb ip, ip, #32 ) |
| 178 | CALGN( sbcnes r4, ip, r2 ) @ C is always set here |
| 179 | CALGN( subcc r2, r2, ip ) |
| 180 | CALGN( bcc 15f ) |
| 181 | |
| 182 | 11: stmfd sp!, {r5 - r9} |
| 183 | |
| 184 | PLD( pld [r1, #0] ) |
| 185 | PLD( subs r2, r2, #96 ) |
| 186 | PLD( pld [r1, #28] ) |
| 187 | PLD( blt 13f ) |
| 188 | PLD( pld [r1, #60] ) |
| 189 | PLD( pld [r1, #92] ) |
| 190 | |
| 191 | 12: PLD( pld [r1, #124] ) |
| 192 | 13: ldr4w r1, r4, r5, r6, r7, abort=19f |
| 193 | mov r3, lr, pull #\pull |
| 194 | subs r2, r2, #32 |
| 195 | ldr4w r1, r8, r9, ip, lr, abort=19f |
| 196 | orr r3, r3, r4, push #\push |
| 197 | mov r4, r4, pull #\pull |
| 198 | orr r4, r4, r5, push #\push |
| 199 | mov r5, r5, pull #\pull |
| 200 | orr r5, r5, r6, push #\push |
| 201 | mov r6, r6, pull #\pull |
| 202 | orr r6, r6, r7, push #\push |
| 203 | mov r7, r7, pull #\pull |
| 204 | orr r7, r7, r8, push #\push |
| 205 | mov r8, r8, pull #\pull |
| 206 | orr r8, r8, r9, push #\push |
| 207 | mov r9, r9, pull #\pull |
| 208 | orr r9, r9, ip, push #\push |
| 209 | mov ip, ip, pull #\pull |
| 210 | orr ip, ip, lr, push #\push |
| 211 | str8w r0, r3, r4, r5, r6, r7, r8, r9, ip, , abort=19f |
| 212 | bge 12b |
| 213 | PLD( cmn r2, #96 ) |
| 214 | PLD( bge 13b ) |
| 215 | |
| 216 | ldmfd sp!, {r5 - r9} |
| 217 | |
| 218 | 14: ands ip, r2, #28 |
| 219 | beq 16f |
| 220 | |
| 221 | 15: mov r3, lr, pull #\pull |
| 222 | ldr1w r1, lr, abort=21f |
| 223 | subs ip, ip, #4 |
| 224 | orr r3, r3, lr, push #\push |
| 225 | str1w r0, r3, abort=21f |
| 226 | bgt 15b |
| 227 | CALGN( cmp r2, #0 ) |
| 228 | CALGN( bge 11b ) |
| 229 | |
| 230 | 16: sub r1, r1, #(\push / 8) |
| 231 | b 8b |
| 232 | |
| 233 | .endm |
| 234 | |
| 235 | |
| 236 | forward_copy_shift pull=8 push=24 |
| 237 | |
| 238 | 17: forward_copy_shift pull=16 push=16 |
| 239 | |
| 240 | 18: forward_copy_shift pull=24 push=8 |