diff options
Diffstat (limited to 'newlib/libc/machine/m68k/memset.S')
| -rw-r--r-- | newlib/libc/machine/m68k/memset.S | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/newlib/libc/machine/m68k/memset.S b/newlib/libc/machine/m68k/memset.S deleted file mode 100644 index 622cf014d..000000000 --- a/newlib/libc/machine/m68k/memset.S +++ /dev/null @@ -1,100 +0,0 @@ -/* a-memset.s -- memset, optimised for fido asm - * - * Copyright (c) 2007 mocom software GmbH & Co KG) - * - * The authors hereby grant permission to use, copy, modify, distribute, - * and license this software and its documentation for any purpose, provided - * that existing copyright notices are retained in all copies and that this - * notice is included verbatim in any distributions. No written agreement, - * license, or royalty fee is required for any of the authorized uses. - * Modifications to this software may be copyrighted by their authors - * and need not follow the licensing terms described here, provided that - * the new terms are clearly indicated on the first page of each file where - * they apply. - */ - -#include "m68kasm.h" - - .text - .align 4 - - .globl SYM(memset) - .type SYM(memset), @function - -| memset, optimised -| -| strategy: -| - no argument testing (the original memcpy from the GNU lib does -| no checking either) -| - make sure the destination pointer (the write pointer) is long word -| aligned. This is the best you can do, because writing to unaligned -| addresses can be the most costfull thing one could do. -| - we fill long word wise if possible -| -| VG, 2006 -| -| bugfixes: -| - distribution of byte value improved - in cases someone gives -| non-byte value -| - residue byte transfer was not working -| -| VG, April 2007 -| -SYM(memset): - move.l 4(sp),a0 | dest ptr - move.l 8(sp),d0 | value - move.l 12(sp),d1 | len - cmp.l #16,d1 - blo .Lbset | below, byte fills - | - move.l d2,-(sp) | need a register - move.b d0,d2 | distribute low byte to all byte in word - lsl.l #8,d0 - move.b d2,d0 - move.w d0,d2 - swap d0 | rotate 16 - move.w d2,d0 - | - move.l a0,d2 | copy of src - neg.l d2 | 1 2 3 ==> 3 2 1 - and.l #3,d2 - beq 2f | is aligned - | - sub.l d2,d1 | fix length - lsr.l #1,d2 | word align needed? - bcc 1f - move.b d0,(a0)+ | fill byte -1: - lsr.l #1,d2 | long align needed? - bcc 2f - move.w d0,(a0)+ | fill word -2: - move.l d1,d2 | number of long transfers (at least 3) - lsr.l #2,d2 - subq.l #1,d2 - -1: - move.l d0,(a0)+ | fill long words -.Llset: -#if !defined (__mcoldfire__) - dbra d2,1b | loop until done - sub.l #0x10000,d2 -#else - subq.l #1,d2 -#endif - bpl 1b - and.l #3,d1 | residue byte transfers, fixed - move.l (sp)+,d2 | restore d2 - bra .Lbset - -1: - move.b d0,(a0)+ | fill residue bytes -.Lbset: -#if !defined (__mcoldfire__) - dbra d1,1b | loop until done -#else - subq.l #1,d1 - bpl 1b -#endif - move.l 4(sp),d0 | return value - rts |