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+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2006 Free Software Foundation, Inc.
+ * This file was originally part of the GNU C Library
+ * Contributed to glibc by MontaVista Software, Inc. (written by Nicolas Pitre)
+ * Adapted for Rockbox by Daniel Ankers
+ *
+ * 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"
+
+/*
+ * Endian independent macros for shifting bytes within registers.
+ */
+#ifndef __ARMEB__
+#define pull lsr
+#define push lsl
+#else
+#define pull lsl
+#define push lsr
+#endif
+
+ .text
+
+/*
+ * Prototype: void *memmove(void *dest, const void *src, size_t n);
+ *
+ * Note:
+ *
+ * If the memory regions don't overlap, we simply branch to memcpy which is
+ * normally a bit faster. Otherwise the copy is done going downwards.
+ */
+
+ .section .icode,"ax",%progbits
+
+ .align 2
+ .global memmove
+ .type memmove,%function
+
+memmove:
+
+ subs ip, r0, r1
+ cmphi r2, ip
+ bls memcpy
+
+ stmfd sp!, {r0, r4, lr}
+ add r1, r1, r2
+ add r0, r0, r2
+ subs r2, r2, #4
+ blt 8f
+ ands ip, r0, #3
+ bne 9f
+ ands ip, r1, #3
+ bne 10f
+
+1: subs r2, r2, #(28)
+ stmfd sp!, {r5 - r8}
+ blt 5f
+
+2:
+3:
+4: ldmdb r1!, {r3, r4, r5, r6, r7, r8, ip, lr}
+ subs r2, r2, #32
+ stmdb r0!, {r3, r4, r5, r6, r7, r8, ip, lr}
+ bge 3b
+
+5: ands ip, r2, #28
+ rsb ip, ip, #32
+ addne pc, pc, ip @ C is always clear here
+ b 7f
+6: nop
+ ldr r3, [r1, #-4]!
+ ldr r4, [r1, #-4]!
+ ldr r5, [r1, #-4]!
+ ldr r6, [r1, #-4]!
+ ldr r7, [r1, #-4]!
+ ldr r8, [r1, #-4]!
+ ldr lr, [r1, #-4]!
+
+ add pc, pc, ip
+ nop
+ nop
+ str r3, [r0, #-4]!
+ str r4, [r0, #-4]!
+ str r5, [r0, #-4]!
+ str r6, [r0, #-4]!
+ str r7, [r0, #-4]!
+ str r8, [r0, #-4]!
+ str lr, [r0, #-4]!
+
+7: ldmfd sp!, {r5 - r8}
+
+8: movs r2, r2, lsl #31
+ ldrneb r3, [r1, #-1]!
+ ldrcsb r4, [r1, #-1]!
+ ldrcsb ip, [r1, #-1]
+ strneb r3, [r0, #-1]!
+ strcsb r4, [r0, #-1]!
+ strcsb ip, [r0, #-1]
+ ldmpc regs="r0, r4"
+
+9: cmp ip, #2
+ ldrgtb r3, [r1, #-1]!
+ ldrgeb r4, [r1, #-1]!
+ ldrb lr, [r1, #-1]!
+ strgtb r3, [r0, #-1]!
+ strgeb r4, [r0, #-1]!
+ subs r2, r2, ip
+ strb lr, [r0, #-1]!
+ blt 8b
+ ands ip, r1, #3
+ beq 1b
+
+10: bic r1, r1, #3
+ cmp ip, #2
+ ldr r3, [r1, #0]
+ beq 17f
+ blt 18f
+
+
+ .macro backward_copy_shift push pull
+
+ subs r2, r2, #28
+ blt 14f
+
+11: stmfd sp!, {r5 - r9}
+
+12:
+13: ldmdb r1!, {r7, r8, r9, ip}
+ mov lr, r3, push #\push
+ subs r2, r2, #32
+ ldmdb r1!, {r3, r4, r5, r6}
+ orr lr, lr, ip, pull #\pull
+ mov ip, ip, push #\push
+ orr ip, ip, r9, pull #\pull
+ mov r9, r9, push #\push
+ orr r9, r9, r8, pull #\pull
+ mov r8, r8, push #\push
+ orr r8, r8, r7, pull #\pull
+ mov r7, r7, push #\push
+ orr r7, r7, r6, pull #\pull
+ mov r6, r6, push #\push
+ orr r6, r6, r5, pull #\pull
+ mov r5, r5, push #\push
+ orr r5, r5, r4, pull #\pull
+ mov r4, r4, push #\push
+ orr r4, r4, r3, pull #\pull
+ stmdb r0!, {r4 - r9, ip, lr}
+ bge 12b
+
+ ldmfd sp!, {r5 - r9}
+
+14: ands ip, r2, #28
+ beq 16f
+
+15: mov lr, r3, push #\push
+ ldr r3, [r1, #-4]!
+ subs ip, ip, #4
+ orr lr, lr, r3, pull #\pull
+ str lr, [r0, #-4]!
+ bgt 15b
+
+16: add r1, r1, #(\pull / 8)
+ b 8b
+
+ .endm
+
+
+ backward_copy_shift push=8 pull=24
+
+17: backward_copy_shift push=16 pull=16
+
+18: backward_copy_shift push=24 pull=8
+
+