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/* Copyright (C) 1999-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
/* void *memcpy(void *dst, const void *src, size_t n);
No overlap between the memory of DST and of SRC are assumed. */
ENTRY(memcpy)
mov r4,r3 /* Save destination. */
/* If less than 11 bytes, just do a byte copy. */
mov #11,r0
cmp/gt r6,r0
bt L_byteloop_init
/* Check if we need to word-align source. */
mov r5,r0
tst #1,r0
bt L_wordalign
mov.b @r0+,r1 /* Copy one byte. */
add #-1,r6
mov.b r1,@r4
add #1,r4
.balignw 4,0x0009
L_wordalign:
/* Check if we need to longword-align source. */
tst #2,r0
bt L_copy
mov.w @r0+,r1 /* Copy one word. */
add #-2,r6
#ifdef __BIG_ENDIAN__
add #1,r4
mov.b r1,@r4
shlr8 r1
mov.b r1,@-r4
add #2,r4
#else
mov.b r1,@r4
add #1,r4
shlr8 r1
mov.b r1,@r4
add #1,r4
#endif
L_copy:
mov r0,r5
/* Calculate the correct routine to handle the destination
alignment and simultaneously calculate the loop counts for
both the 2 word copy loop and byte copy loop. */
mova L_jumptable,r0
mov r0,r1
mov r4,r0
mov r6,r7
and #3,r0
shlr2 r7
shll r0
shlr r7
mov.w @(r0,r1),r2
mov #7,r0
braf r2
and r0,r6
L_base:
.balign 4
L_jumptable:
.word L_copydest0 - L_base
.word L_copydest1_or_3 - L_base
.word L_copydest2 - L_base
.word L_copydest1_or_3 - L_base
.balign 4
/* Copy routine for (dest mod 4) == 1 or == 3. */
L_copydest1_or_3:
add #-1,r4
.balignw 4,0x0009
L_copydest1_or_3_loop:
mov.l @r5+,r0 /* Read first longword. */
dt r7
mov.l @r5+,r1 /* Read second longword. */
#ifdef __BIG_ENDIAN__
/* Write first longword as byte, word, byte. */
mov.b r0,@(4,r4)
shlr8 r0
mov.w r0,@(2,r4)
shlr16 r0
mov.b r0,@(1,r4)
mov r1,r0
/* Write second longword as byte, word, byte. */
mov.b r0,@(8,r4)
shlr8 r0
mov.w r0,@(6,r4)
shlr16 r0
mov.b r0,@(5,r4)
#else
/* Write first longword as byte, word, byte. */
mov.b r0,@(1,r4)
shlr8 r0
mov.w r0,@(2,r4)
shlr16 r0
mov.b r0,@(4,r4)
mov r1,r0
/* Write second longword as byte, word, byte. */
mov.b r0,@(5,r4)
shlr8 r0
mov.w r0,@(6,r4)
shlr16 r0
mov.b r0,@(8,r4)
#endif
bf/s L_copydest1_or_3_loop
add #8,r4
bra L_byteloop_init
add #1,r4
.balign 4
/* Copy routine for (dest mod 4) == 2. */
L_copydest2:
L_copydest2_loop:
mov.l @r5+,r0
dt r7
mov.l @r5+,r1
#ifdef __BIG_ENDIAN__
mov.w r0,@(2,r4)
shlr16 r0
mov.w r0,@r4
mov r1,r0
mov.w r0,@(6,r4)
shlr16 r0
mov.w r0,@(4,r4)
#else
mov.w r0,@r4
shlr16 r0
mov.w r0,@(2,r4)
mov r1,r0
mov.w r0,@(4,r4)
shlr16 r0
mov.w r0,@(6,r4)
#endif
bf/s L_copydest2_loop
add #8,r4
bra L_byteloop_init
nop
.balign 4
/* Copy routine for (dest mod 4) == 0. */
L_copydest0:
add #-8,r4
.balignw 4,0x0009
L_copydest0_loop:
mov.l @r5+,r0
dt r7
mov.l @r5+,r1
add #8,r4
mov.l r0,@r4
bf/s L_copydest0_loop
mov.l r1,@(4,r4)
add #8,r4 /* Fall through. */
L_byteloop_init:
tst r6,r6
bt L_exit
.balignw 4,0x0009
/* Copy remaining bytes. */
L_byteloop:
mov.b @r5+,r0
dt r6
mov.b r0,@r4
bf/s L_byteloop
add #1,r4
L_exit:
rts
mov r3,r0 /* Return destination. */
END(memcpy)
libc_hidden_builtin_def (memcpy)
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