| /* Copyright (c) 2010 Jan Waclawek |
| |
| based on libc/pmstring/memcmp_P.S which is |
| Copyright (c) 2002, 2007 Marek Michalkiewicz |
| Copyright (c) 2007 Dmitry Xmelkov |
| and on exteded program memory routines, which are |
| Copyright (c) 2006, Carlos Lamas |
| |
| 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: memcmp_PF.S 2191 2010-11-05 13:45:57Z arcanum $ */ |
| |
| /** \file */ |
| |
| /** \ingroup avr_pgmspace |
| \fn int memcmp_PF(const void *s1, uint_farptr_t s2, size_t len) |
| \brief Compare memory areas |
| |
| The memcmp_PF() function compares the first \p len bytes of the memory |
| areas \p s1 and flash \p s2. The comparision is performed using unsigned |
| char operations. It is an equivalent of memcmp_P() function, except |
| that it is capable working on all FLASH including the exteded area |
| above 64kB. |
| |
| \returns The memcmp_PF() function returns an integer less than, equal |
| to, or greater than zero if the first \p len bytes of \p s1 is found, |
| respectively, to be less than, to match, or be greater than the first |
| \p len bytes of \p s2. */ |
| |
| |
| #if !defined(__AVR_TINY__) |
| |
| #if !defined(__DOXYGEN__) |
| |
| #include "macros.inc" |
| |
| #define s1_b1 r25 |
| #define s1_b0 r24 |
| #define s2_b3 r23 |
| #define s2_b2 r22 |
| #define s2_b1 r21 |
| #define s2_b0 r20 |
| #define len_b1 r19 |
| #define len_b0 r18 |
| |
| #define ret_b1 r25 |
| #define ret_b0 r24 |
| |
| /* the conditional caters for pre-1.6.8 libc and standalone use */ |
| #ifdef ASSEMBLY_CLIB_SECTION |
| ASSEMBLY_CLIB_SECTION |
| #else |
| .text |
| #endif |
| .global _U(memcmp_PF) |
| .type _U(memcmp_PF), @function |
| _U(memcmp_PF): |
| X_movw ZL, s2_b0 |
| LPM_R0_ZPLUS_INIT s2_b2 |
| X_movw XL, s1_b0 |
| |
| rjmp 2f |
| |
| 1: |
| ld ret_b0, X+ |
| LPM_R0_ZPLUS_NEXT s2_b2 |
| sub ret_b0, r0 |
| brne 3f |
| 2: |
| subi len_b0, lo8(1) |
| sbci len_b1, hi8(1) |
| brsh 1b |
| |
| sub ret_b0, ret_b0 |
| 3: |
| sbc ret_b1, ret_b1 |
| ret |
| |
| .size _U(memcmp_PF), . - _U(memcmp_PF) |
| |
| #endif /* not __DOXYGEN__ */ |
| |
| #endif /* !defined(__AVR_TINY__) */ |