| /* |
| * Copyright (C) 2004-2006 Atmel Corporation |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| /* |
| * void *memcpy(void *to, const void *from, unsigned long n) |
| * |
| * This implementation does word-aligned loads in the main loop, |
| * possibly sacrificing alignment of stores. |
| * |
| * Hopefully, in most cases, both "to" and "from" will be |
| * word-aligned to begin with. |
| */ |
| .text |
| .global memcpy |
| .type memcpy, @function |
| memcpy: |
| mov r9, r11 |
| andl r9, 3, COH |
| brne 1f |
| |
| /* At this point, "from" is word-aligned */ |
| 2: mov r9, r12 |
| 5: sub r10, 4 |
| brlt 4f |
| |
| 3: ld.w r8, r11++ |
| sub r10, 4 |
| st.w r12++, r8 |
| brge 3b |
| |
| 4: neg r10 |
| reteq r9 |
| |
| /* Handle unaligned count */ |
| lsl r10, 2 |
| add pc, pc, r10 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| retal r9 |
| |
| /* Handle unaligned "from" pointer */ |
| 1: sub r10, 4 |
| movlt r9, r12 |
| brlt 4b |
| add r10, r9 |
| lsl r9, 2 |
| add pc, pc, r9 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| ld.ub r8, r11++ |
| st.b r12++, r8 |
| mov r8, r12 |
| add pc, pc, r9 |
| sub r8, 1 |
| nop |
| sub r8, 1 |
| nop |
| sub r8, 1 |
| nop |
| mov r9, r8 |
| rjmp 5b |