/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * * Copyright (C) 2004-2005 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 memcpy .global __memcpy_fwd_entry .type memcpy,@function .global mempcpy .type mempcpy,@function /* Copies bytes of data in memory from to * This version is optimized for speed * * 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 end address (in line-copy loops) * %d0 - data / scratch * %d1 - source end address (byte and longword copy) / 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. */ mempcpy: move.l (4,%sp),%a1 /* Destination */ move.l (8,%sp),%a0 /* Source */ move.l (12,%sp),%d1 /* Length */ add.l %d1,(4,%sp) /* retval=Destination + Length */ bra.b __memcpy_fwd_entry memcpy: move.l (4,%sp),%a1 /* Destination */ move.l (8,%sp),%a0 /* Source */ move.l (12,%sp),%d1 /* Length */ __memcpy_fwd_entry: add.l %a0,%d1 /* %d1 = source end */ move.l %a0,%d0 addq.l #7,%d0 and.l #0xFFFFFFFC,%d0 /* %d0 = first source long bound + 4 */ cmp.l %d0,%d1 /* at least one aligned longword to copy? */ blo.w .bytes2_start /* no, jump directly to trailing byte loop */ subq.l #4,%d0 /* %d0 = first source long bound */ cmp.l %a0,%d0 /* any bytes to copy? */ jls .bytes1_end /* no: skip byte loop */ /* leading byte loop: copies 0..3 bytes */ .bytes1_loop: move.b (%a0)+,(%a1)+ /* copy byte */ cmp.l %a0,%d0 /* runs %a0 up to first long bound */ jhi .bytes1_loop .bytes1_end: moveq.l #31,%d0 add.l %a0,%d0 and.l #0xFFFFFFF0,%d0 /* %d0 = first source line bound + 16 */ cmp.l %d0,%d1 /* at least one aligned line to copy? */ blo.w .long_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 sub.l %d2,%d0 /* %d0 = first source line bound */ move.l %d1,%a2 /* %a2 = end address */ lea.l (-15,%a2),%a2 /* adjust end address for loops doing 16 bytes/ pass */ move.l %a1,%d1 moveq.l #3,%d2 /* mask */ and.l %d2,%d1 jmp.l (2,%pc,%d1.l*4) /* switch (dest_addr & 3) */ bra.w .lines_do0_start bra.w .lines_do1_start bra.w .lines_do2_start /* bra.w .lines_do3_start implicit */ /* byte aligned destination (long + 3): use line burst reads in main loop */ .lines_do3_start: moveq.l #24,%d1 /* shift count for shifting by 3 bytes */ cmp.l %a0,%d0 /* any leading longwords? */ jhi .lines_do3_head_start /* yes: leading longword copy */ movem.l (%a0),%d4-%d7 /* load first line */ lea.l (16,%a0),%a0 move.l %d4,%d2 lsr.l %d1,%d2 /* get high byte of first longword */ move.b %d2,(%a1)+ /* store byte */ jra .lines_do3_entry /* jump into main loop */ .lines_do3_head_start: move.l (%a0)+,%d7 /* load first longword */ move.l %d7,%d2 lsr.l %d1,%d2 /* get high byte */ move.b %d2,(%a1)+ /* store byte */ jra .lines_do3_head_entry /* jump into leading longword loop */ .lines_do3_head_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ move.l %d7,%d2 lsr.l %d1,%d2 /* get high byte */ or.l %d2,%d6 /* combine with old lower 3 bytes */ move.l %d6,(%a1)+ /* store longword */ .lines_do3_head_entry: lsl.l #8,%d7 /* shift up lower 3 bytes */ cmp.l %a0,%d0 /* runs %a0 up to first line bound */ jhi .lines_do3_head_loop .lines_do3_loop: move.l %d7,%d3 /* move last longword of old line away */ movem.l (%a0),%d4-%d7 /* load new line */ lea.l (16,%a0),%a0 move.l %d4,%d2 lsr.l %d1,%d2 /* get high byte of 1st longword */ or.l %d2,%d3 /* combine with old lower 3 bytes */ move.l %d3,(%a1)+ /* store longword */ .lines_do3_entry: lsl.l #8,%d4 /* shift up lower 3 bytes */ move.l %d5,%d2 lsr.l %d1,%d2 /* get high byte of 2nd longword */ or.l %d2,%d4 /* combine with 1st lower 3 bytes */ move.l %d4,(%a1)+ /* store longword */ lsl.l #8,%d5 /* shift up lower 3 bytes */ move.l %d6,%d2 lsr.l %d1,%d2 /* get high byte of 3rd longword */ or.l %d2,%d5 /* combine with 2nd lower 3 bytes */ move.l %d5,(%a1)+ /* store longword */ lsl.l #8,%d6 /* shift up lower 3 bytes */ move.l %d7,%d2 lsr.l %d1,%d2 /* get high byte of 4th longword */ or.l %d2,%d6 /* combine with 3rd lower 3 bytes */ move.l %d6,(%a1)+ /* store longword */ lsl.l #8,%d7 /* shift up lower 3 bytes */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_do3_loop lea.l (12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a0,%a2 /* any trailing longwords? */ jls .lines_do3_tail_end /* no: just store last lower 3 bytes */ .lines_do3_tail_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ move.l %d7,%d2 lsr.l %d1,%d2 /* get high byte */ or.l %d2,%d6 /* combine with old lower 3 bytes */ move.l %d6,(%a1)+ /* store longword */ lsl.l #8,%d7 /* shift up lower 3 bytes */ cmp.l %a0,%a2 /* runs %a0 up to last long bound */ jhi .lines_do3_tail_loop .lines_do3_tail_end: swap %d7 /* get high word */ move.w %d7,(%a1)+ /* store word */ lsr.l %d1,%d7 /* get moved-up low byte */ move.b %d7,(%a1)+ /* store byte */ jra .lines_end /* byte aligned destination (long + 1): use line burst reads in main loop */ .lines_do1_start: moveq.l #24,%d1 /* shift count for shifting by 3 bytes */ cmp.l %a0,%d0 /* any leading longwords? */ jhi .lines_do1_head_start /* yes: leading longword copy */ movem.l (%a0),%d4-%d7 /* load first line */ lea.l (16,%a0),%a0 move.l %d4,%d2 /* first longword, bytes 3210 */ lsr.l #8,%d2 /* first longword, bytes .321 */ swap %d2 /* first longword, bytes 21.3 */ move.b %d2,(%a1)+ /* store byte */ swap %d2 /* first longword, bytes .321 */ move.w %d2,(%a1)+ /* store word */ jra .lines_do1_entry .lines_do1_head_start: move.l (%a0)+,%d7 /* load first longword */ move.l %d7,%d2 /* first longword, bytes 3210 */ lsr.l #8,%d2 /* first longword, bytes .321 */ swap %d2 /* first longword, bytes 21.3 */ move.b %d2,(%a1)+ /* store byte */ swap %d2 /* first longword, bytes .321 */ move.w %d2,(%a1)+ /* store word */ jra .lines_do1_head_entry .lines_do1_head_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ move.l %d7,%d2 lsr.l #8,%d2 /* get upper 3 bytes */ or.l %d2,%d6 /* combine with old low byte */ move.l %d6,(%a1)+ /* store longword */ .lines_do1_head_entry: lsl.l %d1,%d7 /* shift up low byte */ cmp.l %a0,%d0 /* runs %a0 up to first line bound */ jhi .lines_do1_head_loop .lines_do1_loop: move.l %d7,%d3 /* move last longword of old line away */ movem.l (%a0),%d4-%d7 /* load new line */ lea.l (16,%a0),%a0 move.l %d4,%d2 lsr.l #8,%d2 /* get upper 3 bytes of 1st longword */ or.l %d2,%d3 /* combine with low byte of old longword */ move.l %d3,(%a1)+ /* store longword */ .lines_do1_entry: lsl.l %d1,%d4 /* shift up low byte */ move.l %d5,%d2 lsr.l #8,%d2 /* get upper 3 bytes of 2nd longword */ or.l %d2,%d4 /* combine with low byte of 1st longword */ move.l %d4,(%a1)+ /* store longword */ lsl.l %d1,%d5 /* shift up low byte */ move.l %d6,%d2 lsr.l #8,%d2 /* get upper 3 bytes of 3rd longword */ or.l %d2,%d5 /* combine with low byte of 2nd longword */ move.l %d5,(%a1)+ /* store longword */ lsl.l %d1,%d6 /* shift up low byte */ move.l %d7,%d2 lsr.l #8,%d2 /* get upper 3 bytes of 4th longword */ or.l %d2,%d6 /* combine with low byte of 4th longword */ move.l %d6,(%a1)+ /* store longword */ lsl.l %d1,%d7 /* shift up low byte */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_do1_loop lea.l (12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a0,%a2 /* any trailing longwords? */ jls .lines_do1_tail_end /* no: just store last low byte */ .lines_do1_tail_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ move.l %d7,%d2 lsr.l #8,%d2 /* get upper 3 bytes */ or.l %d2,%d6 /* combine with old low byte */ move.l %d6,(%a1)+ /* store longword */ lsl.l %d1,%d7 /* shift up low byte */ cmp.l %a0,%a2 /* runs %a0 up to last long bound */ jhi .lines_do1_tail_loop .lines_do1_tail_end: lsr.l %d1,%d7 /* get shifted-up low byte */ move.b %d7,(%a1)+ /* store byte */ jra .lines_end /* long aligned destination (line + 0/4/8/12): head */ .lines_do0_head_loop: move.l (%a0)+,(%a1)+ /* copy longword */ .lines_do0_start: cmp.l %a0,%d0 /* runs %a0 up to first line bound */ jhi .lines_do0_head_loop .lines_do0_head_end: move.l %a1,%d1 lsr.l #2,%d1 moveq.l #3,%d0 /* mask */ and.l %d0,%d1 moveq.l #16,%d0 /* address increment for one main loop pass */ jmp.l (2,%pc,%d1.l*2) /* switch ((dest_addr >> 2) & 3) */ bra.b .lines_lo0_start bra.b .lines_lo4_start bra.b .lines_lo8_start /* bra.b .lines_lo12_start implicit */ /* long aligned destination (line + 12): use line bursts in the loop */ .lines_lo12_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 move.l %d4,(%a1)+ /* store 1st longword */ cmp.l %a0,%a2 /* any full lines? */ jls .lines_lo12_end /* no: skip main loop */ .lines_lo12_loop: move.l %d5,%d1 /* move last 3 longwords of old line away */ move.l %d6,%d2 move.l %d7,%d3 movem.l (%a0),%d4-%d7 /* load new line */ add.l %d0,%a0 movem.l %d1-%d4,(%a1) /* store line (3 old + 1 new longwords) */ add.l %d0,%a1 cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo12_loop /* long aligned destination (line + 0/4/8/12): tail */ .lines_lo12_end: move.l %d5,(%a1)+ /* store 3rd last longword */ .lines_lo8_end: move.l %d6,(%a1)+ /* store 2nd last longword */ .lines_lo4_end: move.l %d7,(%a1)+ /* store last longword */ .lines_lo0_end: lea.l (12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a0,%a2 /* any trailing longwords? */ jls .lines_end /* no: get outta here */ .lines_do0_tail_loop: move.l (%a0)+,(%a1)+ /* copy longword */ cmp.l %a0,%a2 /* runs %a0 up to last long bound */ jhi .lines_do0_tail_loop jra .lines_end /* line aligned destination: use line bursts in the loop */ .lines_lo0_start: .lines_lo0_loop: movem.l (%a0),%d4-%d7 /* load line */ add.l %d0,%a0 movem.l %d4-%d7,(%a1) /* store line */ add.l %d0,%a1 cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo0_loop jra .lines_lo0_end /* handle trailing longwords */ /* long aligned destination (line + 4): use line bursts in the loop */ .lines_lo4_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 move.l %d4,(%a1)+ /* store 1st longword */ move.l %d5,(%a1)+ /* store 2nd longword */ move.l %d6,(%a1)+ /* store 3rd longword */ cmp.l %a0,%a2 /* any full lines? */ jls .lines_lo4_end /* no: skip main loop */ .lines_lo4_loop: move.l %d7,%d3 /* move last longword of old line away */ movem.l (%a0),%d4-%d7 /* load new line */ add.l %d0,%a0 movem.l %d3-%d6,(%a1) /* store line (1 old + 3 new longwords) */ add.l %d0,%a1 cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo4_loop jra .lines_lo4_end /* handle trailing longwords */ /* long aligned destination (line + 8): use line bursts in the loop */ .lines_lo8_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 move.l %d4,(%a1)+ /* store 1st longword */ move.l %d5,(%a1)+ /* store 2nd longword */ cmp.l %a0,%a2 jls .lines_lo8_end .lines_lo8_loop: move.l %d6,%d2 /* move last 2 longwords of old line away */ move.l %d7,%d3 movem.l (%a0),%d4-%d7 /* load new line */ add.l %d0,%a0 movem.l %d2-%d5,(%a1) /* store line (2 old + 2 new longwords) */ add.l %d0,%a1 cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo8_loop jra .lines_lo8_end /* handle trailing longwords */ #ifdef FULLSPEED /* word aligned destination (line + 2/6/10/14): head */ .lines_do2_start: cmp.l %a0,%d0 /* any leading longwords? */ jls .lines_do2_selector /* no: jump to mainloop selector */ move.l (%a0)+,%d7 /* load first longword */ swap %d7 /* swap words */ move.w %d7,(%a1)+ /* store high word */ cmp.l %a0,%d0 /* any more longword? */ jls .lines_do2_head_end /* no: skip head loop */ .lines_do2_head_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ swap %d7 /* swap words */ move.w %d7,%d6 /* combine high word with old low word */ move.l %d6,(%a1)+ /* store longword */ cmp.l %a0,%d0 /* runs %a0 up to first line bound */ jhi .lines_do2_head_loop .lines_do2_head_end: swap %d7 /* undo swap */ move.w %d7,(%a1)+ /* store word */ .lines_do2_selector: move.l %a1,%d1 lsr.l #2,%d1 moveq.l #3,%d0 /* mask */ and.l %d0,%d1 moveq.l #16,%d0 /* address increment for one main loop pass */ jmp.l (2,%pc,%d1.l*4) /* switch ((dest_addr >> 2) & 3) */ bra.w .lines_lo2_start bra.w .lines_lo6_start bra.w .lines_lo10_start /* bra.w .lines_lo14_start implicit */ /* word aligned destination (line + 14): use line bursts in the loop */ .lines_lo14_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,(%a1)+ /* store word */ jra .lines_lo14_entry /* jump into main loop */ .lines_lo14_loop: move.l %d4,%d0 /* move old line away */ move.l %d5,%d1 move.l %d6,%d2 move.l %d7,%d3 movem.l (%a0),%d4-%d7 /* load new line */ lea.l (16,%a0),%a0 swap %d4 /* swap words of 1st long */ move.w %d4,%d3 /* combine 1st high word with old low word */ movem.l %d0-%d3,(%a1) /* store line */ lea.l (16,%a1),%a1 .lines_lo14_entry: swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo14_loop /* word aligned destination (line + 2/6/10/14): tail */ .lines_lo14_end: move.l %d4,(%a1)+ /* store third last longword */ .lines_lo10_end: move.l %d5,(%a1)+ /* store second last longword */ .lines_lo6_end: move.l %d6,(%a1)+ /* store last longword */ .lines_lo2_end: lea.l (12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a0,%a2 /* any trailing longwords? */ jls .lines_do2_tail_end /* no: skip tail loop */ .lines_do2_tail_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ swap %d7 /* swap words */ move.w %d7,%d6 /* combine high word with old low word */ move.l %d6,(%a1)+ /* store longword */ cmp.l %a0,%a2 /* runs %a0 up to last long bound */ jhi .lines_do2_tail_loop .lines_do2_tail_end: swap %d7 /* undo swap */ move.w %d7,(%a1)+ /* store last word */ jra .lines_end /* word aligned destination (line + 2): use line bursts in the loop */ .lines_lo2_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,(%a1)+ /* store high word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3nd high word with 2nd low word */ swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ move.l %d4,(%a1)+ /* store 1st longword */ move.l %d5,(%a1)+ /* store 2nd longword */ move.l %d6,(%a1)+ /* store 3rd longword */ cmp.l %a0,%a2 /* any full lines? */ jls .lines_lo2_end /* no: skip main loop */ .lines_lo2_loop: move.l %d7,%d3 /* move last longword of old line away */ movem.l (%a0),%d4-%d7 /* load line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,%d3 /* combine 1st high word with old low word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ movem.l %d3-%d6,(%a1) /* store line */ add.l %d0,%a1 cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo2_loop jra .lines_lo2_end /* handle trailing longwords */ /* word aligned destination (line + 6): use line bursts in the loop */ .lines_lo6_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,(%a1)+ /* store high word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ move.l %d4,(%a1)+ /* store 1st longword */ move.l %d5,(%a1)+ /* store 2nd longword */ jra .lines_lo6_entry /* jump into main loop */ .lines_lo6_loop: move.l %d6,%d2 /* move last 2 longwords of old line away */ move.l %d7,%d3 movem.l (%a0),%d4-%d7 /* load line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,%d3 /* combine 1st high word with old low word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ movem.l %d2-%d5,(%a1) /* store line */ add.l %d0,%a1 .lines_lo6_entry: swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo6_loop jra .lines_lo6_end /* handle trailing longwords */ /* word aligned destination (line + 10): use line bursts in the loop */ .lines_lo10_start: movem.l (%a0),%d4-%d7 /* load first line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,(%a1)+ /* store high word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ move.l %d4,(%a1)+ /* store 1st longword */ jra .lines_lo10_entry /* jump into main loop */ .lines_lo10_loop: move.l %d5,%d1 /* move last 3 longwords of old line away */ move.l %d6,%d2 move.l %d7,%d3 movem.l (%a0),%d4-%d7 /* load line */ add.l %d0,%a0 swap %d4 /* swap words of 1st long */ move.w %d4,%d3 /* combine 1st high word with old low word */ swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ movem.l %d1-%d4,(%a1) /* store line */ add.l %d0,%a1 .lines_lo10_entry: swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_lo10_loop jra .lines_lo10_end /* handle trailing longwords */ #else /* !FULLSPEED */ /* word aligned destination (long + 2): use line burst reads in the loop */ .lines_do2_start: cmp.l %a0,%d0 /* any leading longwords? */ jhi .lines_do2_head_start /* yes: leading longword copy */ movem.l (%a0),%d4-%d7 /* load first line */ lea.l (16,%a0),%a0 swap %d4 /* swap words of 1st long */ move.w %d4,(%a1)+ /* store high word */ jra .lines_do2_entry /* jump into main loop */ .lines_do2_head_start: move.l (%a0)+,%d7 /* load first longword */ swap %d7 /* swap words */ move.w %d7,(%a1)+ /* store high word */ cmp.l %a0,%d0 /* any full longword? */ jls .lines_do2_loop /* no: skip head loop */ .lines_do2_head_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ swap %d7 /* swap words */ move.w %d7,%d6 /* combine high word with old low word */ move.l %d6,(%a1)+ /* store longword */ cmp.l %a0,%d0 /* runs %a0 up to first line bound */ jhi .lines_do2_head_loop .lines_do2_loop: move.l %d7,%d3 /* move last longword of old line away */ movem.l (%a0),%d4-%d7 /* load line */ lea.l (16,%a0),%a0 swap %d4 /* swap words of 1st long */ move.w %d4,%d3 /* combine 1st high word with old low word */ move.l %d3,(%a1)+ /* store 1st longword */ .lines_do2_entry: swap %d5 /* swap words of 2nd long */ move.w %d5,%d4 /* combine 2nd high word with 1st low word */ move.l %d4,(%a1)+ /* store 2nd longword */ swap %d6 /* swap words of 3rd long */ move.w %d6,%d5 /* combine 3rd high word with 2nd low word */ move.l %d5,(%a1)+ /* store 3rd longword */ swap %d7 /* swap words of 4th long */ move.w %d7,%d6 /* combine 4th high word with 3rd low word */ move.l %d6,(%a1)+ /* store 4th longword */ cmp.l %a0,%a2 /* runs %a0 up to last line bound */ jhi .lines_do2_loop .lines_do2_end: lea.l (12,%a2),%a2 /* readjust end address for doing longwords */ cmp.l %a0,%a2 /* any trailing longwords? */ jls .lines_do2_tail_end /* no: skip tail loop */ .lines_do2_tail_loop: move.l %d7,%d6 /* move old longword away */ move.l (%a0)+,%d7 /* load new longword */ swap %d7 /* swap words */ move.w %d7,%d6 /* combine high word with old low word */ move.l %d6,(%a1)+ /* store longword */ cmp.l %a0,%a2 /* runs %a0 up to last long bound */ jhi .lines_do2_tail_loop .lines_do2_tail_end: swap %d7 /* undo swap */ move.w %d7,(%a1)+ /* store last word */ /* jra .lines_end implicit */ #endif /* !FULLSPEED */ .lines_end: addq.l #3,%a2 /* readjust end address */ move.l %a2,%d1 /* end address in %d1 again */ movem.l (%sp),%d2-%d7/%a2 /* restore registers */ lea.l (28,%sp),%sp jra .bytes2_start /* jump to trailing byte loop */ .long_start: subq.l #3,%d1 /* adjust end address for doing 4 bytes/ pass */ /* longword copy loop - no lines */ .long_loop: move.l (%a0)+,(%a1)+ /* copy longword (write can be unaligned) */ cmp.l %a0,%d1 /* runs %a0 up to last long bound */ jhi .long_loop addq.l #3,%d1 /* readjust end address */ cmp.l %a0,%d1 /* any bytes left? */ jls .bytes2_end /* no: skip trailing byte loop */ /* trailing byte loop */ .bytes2_loop: move.b (%a0)+,(%a1)+ /* copy byte */ .bytes2_start: cmp.l %a0,%d1 /* runs %a0 up to end address */ jhi .bytes2_loop .bytes2_end: move.l (4,%sp),%d0 /* return destination */ rts .end: .size memcpy,.end-memcpy