/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * * Copyright (C) 2006 by Jens Arnold * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" .section .icode,"ax",@progbits #define FULLSPEED /* use burst writing for word aligned destinations */ .align 2 .global memmove .type memmove,@function /* Moves bytes of data in memory from to * Regions may overlap. * This version is optimized for speed, and needs the corresponding memcpy * implementation for the forward copy branch. * * arguments: * (4,%sp) - destination address * (8,%sp) - source address * (12,%sp) - length * * return value: * %d0 - destination address (like ANSI version) * * register usage: * %a0 - current source address * %a1 - current dest address * %a2 - source start address (in line-copy loops) * %d0 - source start address (byte and longword copy) / data / scratch * %d1 - data / scratch * %d2 - data / scratch * %d3..%d7 - data * * For maximum speed this routine reads and writes whole lines using burst * move (movem.l) where possible. For byte aligned destinations (long-1 and * long-3) it writes longwords only. Same goes for word aligned destinations * if FULLSPEED is undefined. */ memmove: move.l (4,%sp),%a1 /* Destination */ move.l (8,%sp),%a0 /* Source */ move.l (12,%sp),%d1 /* Length */ cmp.l %a0,%a1 bhi.b .backward /* dest > src -> backward copy */ jmp __memcpy_fwd_entry .backward: move.l %a0,%d0 /* %d0 = source start */ add.l %d1,%a0 /* %a0 = source end */ add.l %d1,%a1 /* %a1 = destination end */ move.l %a0,%d1 and.l #0xFFFFFFFC,%d1 /* %d1 = last source long bound */ subq.l #4,%d1 cmp.l %d0,%d1 /* at least one aligned longword to copy? */ blo.w .bytes2r_start addq.l #4,%d1 /* %d1 = last source long bound */ cmp.l %d1,%a0 /* any bytes to copy */ jls .bytes1r_end /* no: skip byte loop */ /* leading byte loop: copies 0..3 bytes */ .bytes1r_loop: move.b -(%a0),-(%a1) /* copy byte */ cmp.l %d1,%a0 /* runs %a0 down to last long bound */ jhi .bytes1r_loop .bytes1r_end: moveq.l #-16,%d1 add.l %a0,%d1 and.l #0xFFFFFFF0,%d1 /* %d1 = last source line bound - 16 */ cmp.l %d0,%d1 /* at least one aligned line to copy? */ blo.w .longr_start /* no: jump to longword copy loop */ lea.l (-28,%sp),%sp /* free up some registers */ movem.l %d2-%d7/%a2,(%sp) moveq.l #16,%d2 add.l %d2,%d1 /* %d1 = last source line bound */ move.l %d0,%a2 /* %a2 = start address */ lea.l (15,%a2),%a2 /* adjust start address for loops doing 16 bytes/pass */ move.l %a1,%d0 moveq.l #3,%d2 /* mask */ and.l %d2,%d0 jmp.l (2,%pc,%d0.l*4) /* switch (dest_addr & 3) */ bra.w .lines_do0r_start bra.w .lines_do1r_start bra.w .lines_do2r_start /* bra.w .lines_do3r_start implicit */ /* byte aligned destination (long - 1): use line burst reads in main loop */ .lines_do3r_start: moveq.l #24,%d0 /* shift count for shifting by 3 bytes */ cmp.l %d1,%a0 /* any leading longwords? */ jhi .lines_do3r_head_start /* yes: leading longword copy */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load initial line */ move.l %d6,%d2 /* last longword, bytes 3210 */ move.b %d2,-(%a1) /* store byte */ lsr.l #8,%d2 /* last longword, bytes .321 */ move.w %d2,-(%a1) /* store word */ jra .lines_do3r_entry .lines_do3r_head_start: move.l -(%a0),%d3 /* load initial longword */ move.l %d3,%d2 /* bytes 3210 */ move.b %d2,-(%a1) /* store byte */ lsr.l #8,%d2 /* bytes .321 */ move.w %d2,-(%a1) /* store word */ jra .lines_do3r_head_entry .lines_do3r_head_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.l %d3,%d2 lsl.l #8,%d2 /* get bytes 210. */ or.l %d2,%d4 /* combine with old high byte */ move.l %d4,-(%a1) /* store longword */ .lines_do3r_head_entry: lsr.l %d0,%d3 /* shift down high byte */ cmp.l %d1,%a0 /* run %a0 down to last line bound */ jhi .lines_do3r_head_loop .lines_do3r_loop: move.l %d3,%d7 /* move first longword of last line away */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load new line */ move.l %d6,%d2 lsl.l #8,%d2 /* get bytes 210. of 4th longword */ or.l %d2,%d7 /* combine with high byte of old longword */ move.l %d7,-(%a1) /* store longword */ .lines_do3r_entry: lsr.l %d0,%d6 /* shift down high byte */ move.l %d5,%d2 lsl.l #8,%d2 /* get bytes 210. of 3rd longword */ or.l %d2,%d6 /* combine with high byte of 4th longword */ move.l %d6,-(%a1) /* store longword */ lsr.l %d0,%d5 /* shift down high byte */ move.l %d4,%d2 lsl.l #8,%d2 /* get bytes 210. of 2nd longword */ or.l %d2,%d5 /* combine with high byte or 3rd longword */ move.l %d5,-(%a1) /* store longword */ lsr.l %d0,%d4 /* shift down high byte */ move.l %d3,%d2 lsl.l #8,%d2 /* get bytes 210. of 1st longword */ or.l %d2,%d4 /* combine with high byte of 2nd longword */ move.l %d4,-(%a1) /* store longword */ lsr.l %d0,%d3 /* shift down high byte */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_do3r_loop lea.l (-12,%a2),%a2 /* readjust start address for doing longwords */ cmp.l %a2,%a0 /* any trailing longwords? */ jls .lines_do3r_tail_end /* no: just store last high byte */ .lines_do3r_tail_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.l %d3,%d2 lsl.l #8,%d2 /* get bytes 210. */ or.l %d2,%d4 /* combine with old high byte */ move.l %d4,-(%a1) /* store longword */ lsr.l %d0,%d3 /* shift down high byte */ cmp.l %a2,%a0 /* run %a0 down to first long bound */ jhi .lines_do3r_tail_loop .lines_do3r_tail_end: move.b %d3,-(%a1) /* store shifted-down high byte */ jra .linesr_end /* byte aligned destination (long - 3): use line burst reads in main loop */ .lines_do1r_start: moveq.l #24,%d0 /* shift count for shifting by 3 bytes */ cmp.l %d1,%a0 /* any leading longwords? */ jhi .lines_do1r_head_start /* yes: leading longword copy */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load initial line */ move.b %d6,-(%a1) /* store low byte of last longword */ jra .lines_do1r_entry .lines_do1r_head_start: move.l -(%a0),%d3 /* load initial longword */ move.b %d3,-(%a1) /* store low byte */ jra .lines_do1r_head_entry .lines_do1r_head_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.l %d3,%d2 lsl.l %d0,%d2 /* get low byte */ or.l %d2,%d4 /* combine with old bytes .321 */ move.l %d4,-(%a1) /* store longword */ .lines_do1r_head_entry: lsr.l #8,%d3 /* get bytes .321 */ cmp.l %d1,%a0 /* run %a0 down to last line bound */ jhi .lines_do1r_head_loop .lines_do1r_loop: move.l %d3,%d7 /* move first longword of old line away */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load new line */ move.l %d6,%d2 lsl.l %d0,%d2 /* get low byte of 4th longword */ or.l %d2,%d7 /* combine with bytes .321 of old longword */ move.l %d7,-(%a1) /* store longword */ .lines_do1r_entry: lsr.l #8,%d6 /* get bytes .321 */ move.l %d5,%d2 lsl.l %d0,%d2 /* get low byte of 3rd longword */ or.l %d2,%d6 /* combine with bytes .321 of 4th longword */ move.l %d6,-(%a1) /* store longword */ lsr.l #8,%d5 /* get bytes .321 */ move.l %d4,%d2 lsl.l %d0,%d2 /* get low byte of 2nd longword */ or.l %d2,%d5 /* combine with bytes .321 of 3rd longword */ move.l %d5,-(%a1) /* store longword */ lsr.l #8,%d4 /* get bytes .321 */ move.l %d3,%d2 lsl.l %d0,%d2 /* get low byte of 1st longword */ or.l %d2,%d4 /* combine with bytes .321 of 2nd longword */ move.l %d4,-(%a1) /* store longword */ lsr.l #8,%d3 /* get bytes .321 */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_do1r_loop lea.l (-12,%a2),%a2 /* readjust start address for doing longwords */ cmp.l %a2,%a0 /* any trailing longwords? */ jls .lines_do1r_tail_end /* no: just store last high byte */ .lines_do1r_tail_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.l %d3,%d2 lsl.l %d0,%d2 /* get low byte */ or.l %d2,%d4 /* combine with old bytes .321 */ move.l %d4,-(%a1) /* store longword */ lsr.l #8,%d3 /* get bytes .321 */ cmp.l %a2,%a0 /* run %a0 down to first long bound */ jhi .lines_do1r_tail_loop .lines_do1r_tail_end: move.w %d3,-(%a1) /* store word 21 */ swap %d3 move.b %d3,-(%a1) /* store byte 3 */ jra .linesr_end /* long aligned destination (line - 0/4/8/12): head */ .lines_do0r_head_loop: move.l -(%a0),-(%a1) /* copy longword */ .lines_do0r_start: cmp.l %d1,%a0 /* run %a0 down to last line bound */ jhi .lines_do0r_head_loop .lines_do0r_head_end: move.l %a1,%d1 lsr.l #2,%d1 moveq.l #3,%d0 /* mask */ and.l %d0,%d1 moveq.l #16,%d0 /* address decrement for one main loop pass */ jmp.l (2,%pc,%d1.l*2) /* switch ((dest_addr >> 2) & 3) */ bra.b .lines_lo0r_start bra.b .lines_lo4r_start bra.b .lines_lo8r_start /* bra.b .lines_lo12r_start implicit */ /* long aligned destination (line - 4): use line bursts in the loop */ .lines_lo12r_start: sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load initial line */ move.l %d4,-(%a1) /* store 4th longword */ move.l %d3,-(%a1) /* store 3rd longword */ move.l %d2,-(%a1) /* store 2nd longword */ cmp.l %a2,%a0 /* any full lines? */ jls .lines_lo12r_end /* no: skip main loop */ .lines_lo12r_loop: move.l %d1,%d5 /* move first longword of old line away */ sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load new line */ sub.l %d0,%a1 movem.l %d2-%d5,(%a1) /* store line (1 old + 3 new longwords */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo12r_loop jra .lines_lo12r_end /* handle trailing longwords */ /* line aligned destination: use line bursts in the loop */ .lines_lo0r_start: .lines_lo0r_loop: sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load line */ sub.l %d0,%a1 movem.l %d1-%d4,(%a1) /* store line */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo0r_loop jra .lines_lo0r_end /* handle trailing longwords */ /* long aligned destination (line - 8): use line bursts in the loop */ .lines_lo8r_start: sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load initial line */ move.l %d4,-(%a1) /* store 4th longword */ move.l %d3,-(%a1) /* store 3rd longword */ cmp.l %a2,%a0 /* any full lines? */ jls .lines_lo8r_end /* no: skip main loop */ .lines_lo8r_loop: move.l %d2,%d6 /* move first 2 longwords of old line away */ move.l %d1,%d5 sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load new line */ sub.l %d0,%a1 movem.l %d3-%d6,(%a1) /* store line (2 old + 2 new longwords */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo8r_loop jra .lines_lo8r_end /* handle trailing longwords */ /* long aligned destination (line - 12): use line bursts in the loop */ .lines_lo4r_start: sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load initial line */ move.l %d4,-(%a1) /* store 4th longword */ cmp.l %a2,%a0 /* any full lines? */ jls .lines_lo4r_end /* no: skip main loop */ .lines_lo4r_loop: move.l %d3,%d7 /* move first 3 longwords of old line away */ move.l %d2,%d6 move.l %d1,%d5 sub.l %d0,%a0 movem.l (%a0),%d1-%d4 /* load new line */ sub.l %d0,%a1 movem.l %d4-%d7,(%a1) /* store line (3 old + 1 new longwords */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo4r_loop /* long aligned destination (line - 0/4/8/12): tail */ .lines_lo4r_end: move.l %d3,-(%a1) /* store 3rd last longword */ .lines_lo8r_end: move.l %d2,-(%a1) /* store 2nd last longword */ .lines_lo12r_end: move.l %d1,-(%a1) /* store last longword */ .lines_lo0r_end: lea.l (-12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a2,%a0 /* any trailing longwords? */ jls .linesr_end /* no: get outta here */ .lines_do0r_tail_loop: move.l -(%a0),-(%a1) /* copy longword */ cmp.l %a2,%a0 /* run %a0 down to first long bound */ jhi .lines_do0r_tail_loop jra .linesr_end #ifdef FULLSPEED /* word aligned destination (line - 2/6/10/14): head */ .lines_do2r_start: cmp.l %d1,%a0 /* any leading longwords? */ jls .lines_do2r_selector /* no: jump to mainloop selector */ move.l -(%a0),%d3 /* load initial longword */ move.w %d3,-(%a1) /* store low word */ cmp.l %d1,%a0 /* any more longwords? */ jls .lines_do2r_head_end /* no: skip head loop */ .lines_do2r_head_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.w %d3,%d4 /* combine low word with old high word */ swap %d4 /* swap words */ move.l %d4,-(%a1) /* store longword */ cmp.l %d1,%a0 /* run %a0 down to last line bound */ jhi .lines_do2r_head_loop .lines_do2r_head_end: swap %d3 /* get high word */ move.w %d3,-(%a1) /* and store it */ .lines_do2r_selector: move.l %a1,%d1 lsr.l #2,%d1 moveq.l #3,%d0 /* mask */ and.l %d0,%d1 moveq.l #16,%d7 /* address decrement for one main loop pass */ jmp.l (2,%pc,%d1.l*4) /* switch ((dest_addr >> 2) & 3) */ bra.w .lines_lo2r_start bra.w .lines_lo6r_start bra.w .lines_lo10r_start /* bra.w .lines_lo14r_start implicit */ /* word aligned destination (line - 2): use line bursts in the loop */ .lines_lo14r_start: sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load initial line */ move.w %d3,-(%a1) /* store last low word */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ move.w %d0,%d1 /* combine 1st low word with 2nd high word */ swap %d1 /* swap words of 1st long */ move.l %d3,-(%a1) /* store 3rd longword */ move.l %d2,-(%a1) /* store 2nd longword */ move.l %d1,-(%a1) /* store 1st longword */ cmp.l %a2,%a0 /* any full lines? */ jls .lines_lo14r_end /* no: skip main loop */ .lines_lo14r_loop: move.l %d0,%d4 /* move first longword of old line away */ sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load line */ move.w %d3,%d4 /* combine 4th low word with old high word */ swap %d4 /* swap words of 4th long */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ move.w %d0,%d1 /* combine 1st low word with 2nd high word */ swap %d1 /* swap words of 1st long */ sub.l %d7,%a1 movem.l %d1-%d4,(%a1) /* store line */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo14r_loop jra .lines_lo14r_end /* handle trailing longwords */ /* word aligned destination (line - 6): use line bursts in the loop */ .lines_lo10r_start: sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load initial line */ move.w %d3,-(%a1) /* store last low word */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ move.l %d3,-(%a1) /* store 3rd longword */ move.l %d2,-(%a1) /* store 2nd longword */ jra .lines_lo10r_entry /* jump into main loop */ .lines_lo10r_loop: move.l %d0,%d4 /* move first 2 longwords of old line away */ move.l %d1,%d5 sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load line */ move.w %d3,%d4 /* combine 4th low word with old high word */ swap %d4 /* swap words of 4th long */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ sub.l %d7,%a1 movem.l %d2-%d5,(%a1) /* store line */ .lines_lo10r_entry: move.w %d0,%d1 /* combine 1st low word with 2nd high word */ swap %d1 /* swap words of 1st long */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo10r_loop jra .lines_lo10r_end /* handle trailing longwords */ /* word aligned destination (line - 10): use line bursts in the loop */ .lines_lo6r_start: sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load initial line */ move.w %d3,-(%a1) /* store last low word */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.l %d3,-(%a1) /* store 3rd longword */ jra .lines_lo6r_entry /* jump into main loop */ .lines_lo6r_loop: move.l %d0,%d4 /* move first 3 longwords of old line away */ move.l %d1,%d5 move.l %d2,%d6 sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load line */ move.w %d3,%d4 /* combine 4th low word with old high word */ swap %d4 /* swap words of 4th long */ move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ sub.l %d7,%a1 movem.l %d3-%d6,(%a1) /* store line */ .lines_lo6r_entry: move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ move.w %d0,%d1 /* combine 1st low word with 2nd high word */ swap %d1 /* swap words of 1st long */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo6r_loop jra .lines_lo6r_end /* handle trailing longwords */ /* word aligned destination (line - 14): use line bursts in the loop */ .lines_lo2r_start: sub.l %d7,%a0 movem.l (%a0),%d0-%d3 /* load initial line */ move.w %d3,-(%a1) /* store last low word */ jra .lines_lo2r_entry /* jump into main loop */ .lines_lo2r_loop: move.l %d0,%d4 /* move old line away */ move.l %d1,%d5 move.l %d2,%d6 move.l %d3,%d7 lea.l (-16,%a0),%a0 movem.l (%a0),%d0-%d3 /* load line */ move.w %d3,%d4 /* combine 4th low word with old high word */ swap %d4 /* swap words of 4th long */ lea.l (-16,%a1),%a1 movem.l %d4-%d7,(%a1) /* store line */ .lines_lo2r_entry: move.w %d2,%d3 /* combine 3rd low word with 4th high word */ swap %d3 /* swap words of 3rd long */ move.w %d1,%d2 /* combine 2nd low word with 3rd high word */ swap %d2 /* swap words of 2nd long */ move.w %d0,%d1 /* combine 1st low word with 2nd high word */ swap %d1 /* swap words of 1st long */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_lo2r_loop /* word aligned destination (line - 2/6/10/14): tail */ .lines_lo2r_end: move.l %d3,-(%a1) /* store third last longword */ .lines_lo6r_end: move.l %d2,-(%a1) /* store second last longword */ .lines_lo10r_end: move.l %d1,-(%a1) /* store last longword */ .lines_lo14r_end: lea.l (-12,%a2),%a2 /* readjust start address for doing longwords */ cmp.l %a2,%a0 /* any trailing longwords? */ jls .lines_do2r_tail_end /* no: skip tail loop */ .lines_do2r_tail_loop: move.l %d0,%d1 /* move old longword away */ move.l -(%a0),%d0 /* load new longword */ move.w %d0,%d1 /* combine low word with old high word */ swap %d1 /* swap words */ move.l %d1,-(%a1) /* store longword */ cmp.l %a2,%a0 /* run %a0 down to first long bound */ jhi .lines_do2r_tail_loop .lines_do2r_tail_end: swap %d0 /* get final high word */ move.w %d0,-(%a1) /* store it */ /* jra .linesr_end implicit */ #else /* !FULLSPEED */ /* word aligned destination (long - 2): use line burst reads in the loop */ .lines_do2r_start: cmp.l %d1,%a0 /* any leading longwords? */ jhi .lines_do2r_head_start /* yes: leading longword copy */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load initial line */ move.w %d6,-(%a1) /* store last low word */ jra .lines_do2r_entry /* jump into main loop */ .lines_do2r_head_start: move.l -(%a0),%d3 /* load initial longword */ move.w %d3,-(%a1) /* store low word */ cmp.l %d1,%a0 /* any full longword? */ jls .lines_do2r_loop /* no: skip head loop */ .lines_do2r_head_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.w %d3,%d4 /* combine low word with old high word */ swap %d4 /* swap words */ move.l %d4,-(%a1) /* store longword */ cmp.l %d1,%a0 /* run %a0 down to last line bound */ jhi .lines_do2r_head_loop .lines_do2r_loop: move.l %d3,%d7 /* move first longword of old line away */ lea.l (-16,%a0),%a0 movem.l (%a0),%d3-%d6 /* load line */ move.w %d6,%d7 /* combine 4th low word with old high word */ swap %d7 /* swap words of 4th long */ move.l %d7,-(%a1) /* store 4th longword */ .lines_do2r_entry: move.w %d5,%d6 /* combine 3rd low word with 4th high word */ swap %d6 /* swap words of 3rd long */ move.l %d6,-(%a1) /* store 3rd longword */ move.w %d4,%d5 /* combine 2nd low word with 3rd high word */ swap %d5 /* swap words of 2nd long */ move.l %d5,-(%a1) /* store 2nd longword */ move.w %d3,%d4 /* combine 1st low word with 2nd high word */ swap %d4 /* swap words of 1st long */ move.l %d4,-(%a1) /* store 1st longword */ cmp.l %a2,%a0 /* run %a0 down to first line bound */ jhi .lines_do2r_loop .lines_do2r_end: lea.l (-12,%a2),%a2 /* readjust start address for doing longwords */ cmp.l %a2,%a0 /* any trailing longwords? */ jls .lines_do2r_tail_end /* no: skip tail loop */ .lines_do2r_tail_loop: move.l %d3,%d4 /* move old longword away */ move.l -(%a0),%d3 /* load new longword */ move.w %d3,%d4 /* combine low word with old high word */ swap %d4 /* swap words */ move.l %d4,-(%a1) /* store longword */ cmp.l %a2,%a0 /* run %a0 down to first long bound */ jhi .lines_do2r_tail_loop .lines_do2r_tail_end: swap %d3 /* get final high word */ move.w %d3,-(%a1) /* store it */ /* jra .linesr_end implicit */ #endif /* !FULLSPEED */ .linesr_end: subq.l #3,%a2 /* readjust end address */ move.l %a2,%d0 /* start address in %d0 again */ movem.l (%sp),%d2-%d7/%a2 /* restore registers */ lea.l (28,%sp),%sp jra .bytes2r_start /* jump to trailing byte loop */ .longr_start: addq.l #3,%d0 /* adjust start address for doing 4 bytes/ pass */ /* longword copy loop - no lines */ .longr_loop: move.l -(%a0),-(%a1) /* copy longword (write can be unaligned) */ cmp.l %d0,%a0 /* runs %a0 down to first long bound */ jhi .longr_loop subq.l #3,%d0 /* readjust start address */ cmp.l %d0,%a0 /* any bytes left? */ jls .bytes2r_end /* no: skip trailing byte loop */ /* trailing byte loop */ .bytes2r_loop: move.b -(%a0),-(%a1) /* copy byte */ .bytes2r_start: cmp.l %d0,%a0 /* runs %a0 down to start address */ jhi .bytes2r_loop .bytes2r_end: rts /* returns start address */ .end: .size memmove,.end-memmove