| /* Copyright (c) 2002, 2007 Marek Michalkiewicz |
| All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are met: |
| |
| * Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| * Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in |
| the documentation and/or other materials provided with the |
| distribution. |
| * Neither the name of the copyright holders nor the names of |
| contributors may be used to endorse or promote products derived |
| from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. */ |
| |
| /* $Id: memcpy.S 1944 2009-04-01 23:12:20Z arcanum $ */ |
| |
| /** \file */ |
| /** \ingroup avr_string |
| \fn void *memcpy(void *dest, const void *src, size_t len) |
| \brief Copy a memory area. |
| |
| The memcpy() function copies len bytes from memory area src to memory area |
| dest. The memory areas may not overlap. Use memmove() if the memory |
| areas do overlap. |
| |
| \returns The memcpy() function returns a pointer to dest. */ |
| |
| #if !defined(__DOXYGEN__) |
| |
| #include "macros.inc" |
| |
| #define dest_hi r25 |
| #define dest_lo r24 |
| #define src_hi r23 |
| #define src_lo r22 |
| #define len_hi r21 |
| #define len_lo r20 |
| |
| ASSEMBLY_CLIB_SECTION |
| .global _U(memcpy) |
| .type _U(memcpy), @function |
| _U(memcpy): |
| X_movw ZL, src_lo |
| X_movw XL, dest_lo |
| #if OPTIMIZE_SPEED |
| ; 15 words, (14 + len * 6 - (len & 1)) cycles |
| sbrs len_lo, 0 |
| rjmp .L_memcpy_start |
| rjmp .L_memcpy_odd |
| .L_memcpy_loop: |
| ld __tmp_reg__, Z+ |
| st X+, __tmp_reg__ |
| .L_memcpy_odd: |
| ld __tmp_reg__, Z+ |
| st X+, __tmp_reg__ |
| .L_memcpy_start: |
| subi len_lo, lo8(2) |
| sbci len_hi, hi8(2) |
| #else |
| ; 11 words, (13 + len * 8) cycles |
| rjmp .L_memcpy_start |
| .L_memcpy_loop: |
| ld __tmp_reg__, Z+ |
| st X+, __tmp_reg__ |
| .L_memcpy_start: |
| subi len_lo, lo8(1) |
| sbci len_hi, hi8(1) |
| #endif |
| brcc .L_memcpy_loop |
| ; return dest (unchanged) |
| ret |
| .L_memcpy_end: |
| .size _U(memcpy), .L_memcpy_end - _U(memcpy) |
| |
| #endif /* not __DOXYGEN__ */ |