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diff --git a/firmware/target/sh/memcpy-sh.S b/firmware/target/sh/memcpy-sh.S
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+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2004-2005 by Jens Arnold
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * 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
+
+ .align 2
+ .global _memcpy
+ .global ___memcpy_fwd_entry
+ .type _memcpy,@function
+
+/* Copies <length> bytes of data in memory from <source> to <dest>
+ * This version is optimized for speed
+ *
+ * arguments:
+ * r4 - destination address
+ * r5 - source address
+ * r6 - length
+ *
+ * return value:
+ * r0 - destination address (like ANSI version)
+ *
+ * register usage:
+ * r0 - data / scratch
+ * r1 - 2nd data / scratch
+ * r2 - scratch
+ * r3 - first long bound / adjusted end address (only if >= 11 bytes)
+ * r4 - current dest address
+ * r5 - current source address
+ * r6 - source end address
+ * r7 - stored dest start address
+ *
+ * The instruction order is devised in a way to utilize the pipelining
+ * of the SH1 to the max. The routine also tries to utilize fast page mode.
+ */
+
+_memcpy:
+ mov r4,r7 /* store dest for returning */
+___memcpy_fwd_entry:
+ add #-8,r4 /* offset for early increment (max. 2 longs) */
+ mov #11,r0
+ cmp/hs r0,r6 /* at least 11 bytes to copy? (ensures 2 aligned longs) */
+ add r5,r6 /* r6 = source_end */
+ bf .start_b2 /* no: jump directly to byte loop */
+
+ mov #3,r0
+ neg r5,r3
+ and r0,r3 /* r3 = (4 - align_offset) % 4 */
+ tst r3,r3 /* already aligned? */
+ bt .end_b1 /* yes: skip leading byte loop */
+
+ add r5,r3 /* r3 = first source long bound */
+
+ /* leading byte loop: copies 0..3 bytes */
+.loop_b1:
+ mov.b @r5+,r0 /* load byte & increment source addr */
+ add #1,r4 /* increment dest addr */
+ mov.b r0,@(7,r4) /* store byte */
+ cmp/hi r5,r3 /* runs r5 up to first long bound */
+ bt .loop_b1
+ /* now r5 is always at a long boundary */
+ /* -> memory reading is done in longs for all dest alignments */
+
+ /* selector for main copy loop */
+.end_b1:
+ mov #3,r1
+ and r4,r1 /* r1 = dest alignment offset */
+ mova .jmptab,r0
+ mov.b @(r0,r1),r1 /* select appropriate main loop */
+ add r0,r1
+ mov r6,r3 /* move end address to r3 */
+ jmp @r1 /* and jump to it */
+ add #-7,r3 /* adjust end addr for main loops doing 2 longs/pass */
+
+ /** main loops, copying 2 longs per pass to profit from fast page mode **/
+
+ /* long aligned destination (fastest) */
+ .align 2
+.loop_do0:
+ mov.l @r5+,r1 /* load first long & increment source addr */
+ add #16,r4 /* increment dest addr & account for decrementing stores */
+ mov.l @r5+,r0 /* load second long & increment source addr */
+ cmp/hi r5,r3 /* runs r5 up to last or second last long bound */
+ mov.l r0,@-r4 /* store second long */
+ mov.l r1,@-r4 /* store first long; NOT ALIGNED - no speed loss here! */
+ bt .loop_do0
+
+ add #4,r3 /* readjust end address */
+ cmp/hi r5,r3 /* one long left? */
+ bf .start_b2 /* no, jump to trailing byte loop */
+
+ mov.l @r5+,r0 /* load last long & increment source addr */
+ add #4,r4 /* increment dest addr */
+ bra .start_b2 /* jump to trailing byte loop */
+ mov.l r0,@(4,r4) /* store last long */
+
+ /* word aligned destination (long + 2) */
+ .align 2
+.loop_do2:
+ mov.l @r5+,r1 /* load first long & increment source addr */
+ add #16,r4 /* increment dest addr */
+ mov.l @r5+,r0 /* load second long & increment source addr */
+ cmp/hi r5,r3 /* runs r5 up to last or second last long bound */
+ mov.w r0,@-r4 /* store low word of second long */
+ xtrct r1,r0 /* extract low word of first long & high word of second long */
+ mov.l r0,@-r4 /* and store as long */
+ swap.w r1,r0 /* get high word of first long */
+ mov.w r0,@-r4 /* and store it */
+ bt .loop_do2
+
+ add #4,r3 /* readjust end address */
+ cmp/hi r5,r3 /* one long left? */
+ bf .start_b2 /* no, jump to trailing byte loop */
+
+ mov.l @r5+,r0 /* load last long & increment source addr */
+ add #4,r4 /* increment dest addr */
+ mov.w r0,@(6,r4) /* store low word */
+ shlr16 r0 /* get high word */
+ bra .start_b2 /* jump to trailing byte loop */
+ mov.w r0,@(4,r4) /* and store it */
+
+ /* jumptable for loop selector */
+ .align 2
+.jmptab:
+ .byte .loop_do0 - .jmptab /* placed in the middle because the SH1 */
+ .byte .loop_do1 - .jmptab /* loads bytes sign-extended. Otherwise */
+ .byte .loop_do2 - .jmptab /* the last loop would be out of reach */
+ .byte .loop_do3 - .jmptab /* of the offset range. */
+
+ /* byte aligned destination (long + 1) */
+ .align 2
+.loop_do1:
+ mov.l @r5+,r1 /* load first long & increment source addr */
+ add #16,r4 /* increment dest addr */
+ mov.l @r5+,r0 /* load second long & increment source addr */
+ cmp/hi r5,r3 /* runs r5 up to last or second last long bound */
+ mov.b r0,@-r4 /* store low byte of second long */
+ shlr8 r0 /* get upper 3 bytes */
+ mov r1,r2 /* copy first long */
+ shll16 r2 /* move low byte of first long all the way up, .. */
+ shll8 r2
+ or r2,r0 /* ..combine with the 3 bytes of second long.. */
+ mov.l r0,@-r4 /* ..and store as long */
+ shlr8 r1 /* get middle 2 bytes */
+ mov.w r1,@-r4 /* store as word */
+ shlr16 r1 /* get upper byte */
+ mov.b r1,@-r4 /* and store */
+ bt .loop_do1
+
+ add #4,r3 /* readjust end address */
+.last_do13:
+ cmp/hi r5,r3 /* one long left? */
+ bf .start_b2 /* no, jump to trailing byte loop */
+
+ mov.l @r5+,r0 /* load last long & increment source addr */
+ add #12,r4 /* increment dest addr */
+ mov.b r0,@-r4 /* store low byte */
+ shlr8 r0 /* get middle 2 bytes */
+ mov.w r0,@-r4 /* store as word */
+ shlr16 r0 /* get upper byte */
+ mov.b r0,@-r4 /* and store */
+ bra .start_b2 /* jump to trailing byte loop */
+ add #-4,r4 /* readjust destination */
+
+ /* byte aligned destination (long + 3) */
+ .align 2
+.loop_do3:
+ mov.l @r5+,r1 /* load first long & increment source addr */
+ add #16,r4 /* increment dest addr */
+ mov.l @r5+,r0 /* load second long & increment source addr */
+ mov r1,r2 /* copy first long */
+ mov.b r0,@-r4 /* store low byte of second long */
+ shlr8 r0 /* get middle 2 bytes */
+ mov.w r0,@-r4 /* store as word */
+ shlr16 r0 /* get upper byte */
+ shll8 r2 /* move lower 3 bytes of first long one up.. */
+ or r2,r0 /* ..combine with the 1 byte of second long.. */
+ mov.l r0,@-r4 /* ..and store as long */
+ shlr16 r1 /* get upper byte of first long.. */
+ shlr8 r1
+ cmp/hi r5,r3 /* runs r5 up to last or second last long bound */
+ mov.b r1,@-r4 /* ..and store */
+ bt .loop_do3
+
+ bra .last_do13 /* handle last longword: reuse routine for (long + 1) */
+ add #4,r3 /* readjust end address */
+
+ /* trailing byte loop: copies 0..3 bytes (or all for < 11 in total) */
+ .align 2
+.loop_b2:
+ mov.b @r5+,r0 /* load byte & increment source addr */
+ add #1,r4 /* increment dest addr */
+ mov.b r0,@(7,r4) /* store byte */
+.start_b2:
+ cmp/hi r5,r6 /* runs r5 up to end address */
+ bt .loop_b2
+
+ rts
+ mov r7,r0 /* return dest start address */
+.end:
+ .size _memcpy,.end-_memcpy