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/* Copyright (C) 2006-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by MontaVista Software, Inc. (written by Nicolas Pitre)
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
<http://www.gnu.org/licenses/>. */
/* Thumb requires excessive IT insns here. */
#define NO_THUMB
#include <sysdep.h>
#include <arm-features.h>
/*
* Data preload for architectures that support it (ARM V5TE and above)
*/
#if (!defined (__ARM_ARCH_2__) && !defined (__ARM_ARCH_3__) \
&& !defined (__ARM_ARCH_3M__) && !defined (__ARM_ARCH_4__) \
&& !defined (__ARM_ARCH_4T__) && !defined (__ARM_ARCH_5__) \
&& !defined (__ARM_ARCH_5T__))
#define PLD(code...) code
#else
#define PLD(code...)
#endif
/*
* This can be used to enable code to cacheline align the source pointer.
* Experiments on tested architectures (StrongARM and XScale) didn't show
* this a worthwhile thing to do. That might be different in the future.
*/
//#define CALGN(code...) code
#define CALGN(code...)
/*
* 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
.syntax unified
/* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
ENTRY(memcpy)
push {r0, r4, lr}
cfi_adjust_cfa_offset (12)
cfi_rel_offset (r4, 4)
cfi_rel_offset (lr, 8)
cfi_remember_state
subs r2, r2, #4
blt 8f
ands ip, r0, #3
PLD( pld [r1, #0] )
bne 9f
ands ip, r1, #3
bne 10f
1: subs r2, r2, #(28)
push {r5 - r8}
cfi_adjust_cfa_offset (16)
cfi_rel_offset (r5, 0)
cfi_rel_offset (r6, 4)
cfi_rel_offset (r7, 8)
cfi_rel_offset (r8, 12)
blt 5f
CALGN( ands ip, r1, #31 )
CALGN( rsb r3, ip, #32 )
CALGN( sbcsne r4, r3, r2 ) @ C is always set here
CALGN( bcs 2f )
CALGN( adr r4, 6f )
CALGN( subs r2, r2, r3 ) @ C gets set
#ifndef ARM_ALWAYS_BX
CALGN( add pc, r4, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2))
#else
CALGN( add r4, r4, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2))
CALGN( bx r4 )
#endif
PLD( pld [r1, #0] )
2: PLD( subs r2, r2, #96 )
PLD( pld [r1, #28] )
PLD( blt 4f )
PLD( pld [r1, #60] )
PLD( pld [r1, #92] )
3: PLD( pld [r1, #124] )
4: ldmia r1!, {r3, r4, r5, r6, r7, r8, ip, lr}
subs r2, r2, #32
stmia r0!, {r3, r4, r5, r6, r7, r8, ip, lr}
bge 3b
PLD( cmn r2, #96 )
PLD( bge 4b )
5: ands ip, r2, #28
rsb ip, ip, #32
#ifndef ARM_ALWAYS_BX
/* C is always clear here. */
addne pc, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
b 7f
#else
beq 7f
push {r10}
cfi_adjust_cfa_offset (4)
cfi_rel_offset (r10, 0)
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
6: nop
.p2align ARM_BX_ALIGN_LOG2
ldr r3, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr r4, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr r5, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr r6, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr r7, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr r8, [r1], #4
.p2align ARM_BX_ALIGN_LOG2
ldr lr, [r1], #4
#ifndef ARM_ALWAYS_BX
add pc, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
nop
#else
add r10, pc, ip, lsl #(ARM_BX_ALIGN_LOG2 - 2)
bx r10
#endif
.p2align ARM_BX_ALIGN_LOG2
nop
.p2align ARM_BX_ALIGN_LOG2
str r3, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str r4, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str r5, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str r6, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str r7, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str r8, [r0], #4
.p2align ARM_BX_ALIGN_LOG2
str lr, [r0], #4
#ifdef ARM_ALWAYS_BX
pop {r10}
cfi_adjust_cfa_offset (-4)
cfi_restore (r10)
#endif
CALGN( bcs 2b )
7: pop {r5 - r8}
cfi_adjust_cfa_offset (-16)
cfi_restore (r5)
cfi_restore (r6)
cfi_restore (r7)
cfi_restore (r8)
8: movs r2, r2, lsl #31
ldrbne r3, [r1], #1
ldrbcs r4, [r1], #1
ldrbcs ip, [r1]
strbne r3, [r0], #1
strbcs r4, [r0], #1
strbcs ip, [r0]
#if ((defined (__ARM_ARCH_4T__) && defined(__THUMB_INTERWORK__)) \
|| defined (ARM_ALWAYS_BX))
pop {r0, r4, lr}
cfi_adjust_cfa_offset (-12)
cfi_restore (r4)
cfi_restore (lr)
bx lr
#else
pop {r0, r4, pc}
#endif
cfi_restore_state
9: rsb ip, ip, #4
cmp ip, #2
ldrbgt r3, [r1], #1
ldrbge r4, [r1], #1
ldrb lr, [r1], #1
strbgt r3, [r0], #1
strbge 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 lr, [r1], #4
beq 17f
bgt 18f
.macro forward_copy_shift pull push
subs r2, r2, #28
blt 14f
CALGN( ands ip, r1, #31 )
CALGN( rsb ip, ip, #32 )
CALGN( sbcsne r4, ip, r2 ) @ C is always set here
CALGN( subcc r2, r2, ip )
CALGN( bcc 15f )
11: push {r5 - r8, r10}
cfi_adjust_cfa_offset (20)
cfi_rel_offset (r5, 0)
cfi_rel_offset (r6, 4)
cfi_rel_offset (r7, 8)
cfi_rel_offset (r8, 12)
cfi_rel_offset (r10, 16)
PLD( pld [r1, #0] )
PLD( subs r2, r2, #96 )
PLD( pld [r1, #28] )
PLD( blt 13f )
PLD( pld [r1, #60] )
PLD( pld [r1, #92] )
12: PLD( pld [r1, #124] )
13: ldmia r1!, {r4, r5, r6, r7}
mov r3, lr, PULL #\pull
subs r2, r2, #32
ldmia r1!, {r8, r10, ip, lr}
orr r3, r3, r4, PUSH #\push
mov r4, r4, PULL #\pull
orr r4, r4, r5, PUSH #\push
mov r5, r5, PULL #\pull
orr r5, r5, r6, PUSH #\push
mov r6, r6, PULL #\pull
orr r6, r6, r7, PUSH #\push
mov r7, r7, PULL #\pull
orr r7, r7, r8, PUSH #\push
mov r8, r8, PULL #\pull
orr r8, r8, r10, PUSH #\push
mov r10, r10, PULL #\pull
orr r10, r10, ip, PUSH #\push
mov ip, ip, PULL #\pull
orr ip, ip, lr, PUSH #\push
stmia r0!, {r3, r4, r5, r6, r7, r8, r10, ip}
bge 12b
PLD( cmn r2, #96 )
PLD( bge 13b )
pop {r5 - r8, r10}
cfi_adjust_cfa_offset (-20)
cfi_restore (r5)
cfi_restore (r6)
cfi_restore (r7)
cfi_restore (r8)
cfi_restore (r10)
14: ands ip, r2, #28
beq 16f
15: mov r3, lr, PULL #\pull
ldr lr, [r1], #4
subs ip, ip, #4
orr r3, r3, lr, PUSH #\push
str r3, [r0], #4
bgt 15b
CALGN( cmp r2, #0 )
CALGN( bge 11b )
16: sub r1, r1, #(\push / 8)
b 8b
.endm
forward_copy_shift pull=8 push=24
17: forward_copy_shift pull=16 push=16
18: forward_copy_shift pull=24 push=8
END(memcpy)
libc_hidden_builtin_def (memcpy)
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