mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-14 15:54:15 +08:00
Merge branch 'arm64-klib' into upstream
* arm64-klib: arm64: klib: Optimised atomic bitops arm64: klib: Optimised string functions arm64: klib: Optimised memory functions
This commit is contained in:
commit
d4784be3b2
@ -39,7 +39,6 @@ generic-y += shmbuf.h
|
|||||||
generic-y += sizes.h
|
generic-y += sizes.h
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||||||
generic-y += socket.h
|
generic-y += socket.h
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||||||
generic-y += sockios.h
|
generic-y += sockios.h
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||||||
generic-y += string.h
|
|
||||||
generic-y += switch_to.h
|
generic-y += switch_to.h
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||||||
generic-y += swab.h
|
generic-y += swab.h
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||||||
generic-y += termbits.h
|
generic-y += termbits.h
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||||||
|
@ -32,6 +32,16 @@
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|||||||
#error only <linux/bitops.h> can be included directly
|
#error only <linux/bitops.h> can be included directly
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#endif
|
#endif
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||||||
|
|
||||||
|
/*
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|
* Little endian assembly atomic bitops.
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||||||
|
*/
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||||||
|
extern void set_bit(int nr, volatile unsigned long *p);
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||||||
|
extern void clear_bit(int nr, volatile unsigned long *p);
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|
extern void change_bit(int nr, volatile unsigned long *p);
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|
extern int test_and_set_bit(int nr, volatile unsigned long *p);
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|
extern int test_and_clear_bit(int nr, volatile unsigned long *p);
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extern int test_and_change_bit(int nr, volatile unsigned long *p);
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|
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||||||
#include <asm-generic/bitops/builtin-__ffs.h>
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#include <asm-generic/bitops/builtin-__ffs.h>
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#include <asm-generic/bitops/builtin-ffs.h>
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#include <asm-generic/bitops/builtin-ffs.h>
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#include <asm-generic/bitops/builtin-__fls.h>
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#include <asm-generic/bitops/builtin-__fls.h>
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@ -45,9 +55,13 @@
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#include <asm-generic/bitops/hweight.h>
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#include <asm-generic/bitops/hweight.h>
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#include <asm-generic/bitops/lock.h>
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#include <asm-generic/bitops/lock.h>
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|
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||||||
#include <asm-generic/bitops/atomic.h>
|
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||||||
#include <asm-generic/bitops/non-atomic.h>
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#include <asm-generic/bitops/non-atomic.h>
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#include <asm-generic/bitops/le.h>
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#include <asm-generic/bitops/le.h>
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#include <asm-generic/bitops/ext2-atomic.h>
|
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||||||
|
/*
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|
* Ext2 is defined to use little-endian byte ordering.
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||||||
|
*/
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||||||
|
#define ext2_set_bit_atomic(lock, nr, p) test_and_set_bit_le(nr, p)
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|
#define ext2_clear_bit_atomic(lock, nr, p) test_and_clear_bit_le(nr, p)
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|
|
||||||
#endif /* __ASM_BITOPS_H */
|
#endif /* __ASM_BITOPS_H */
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||||||
|
37
arch/arm64/include/asm/string.h
Normal file
37
arch/arm64/include/asm/string.h
Normal file
@ -0,0 +1,37 @@
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|||||||
|
/*
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
#ifndef __ASM_STRING_H
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|
#define __ASM_STRING_H
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||||||
|
|
||||||
|
#define __HAVE_ARCH_STRRCHR
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||||||
|
extern char *strrchr(const char *, int c);
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||||||
|
|
||||||
|
#define __HAVE_ARCH_STRCHR
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||||||
|
extern char *strchr(const char *, int c);
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||||||
|
|
||||||
|
#define __HAVE_ARCH_MEMCPY
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||||||
|
extern void *memcpy(void *, const void *, __kernel_size_t);
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||||||
|
|
||||||
|
#define __HAVE_ARCH_MEMMOVE
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||||||
|
extern void *memmove(void *, const void *, __kernel_size_t);
|
||||||
|
|
||||||
|
#define __HAVE_ARCH_MEMCHR
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||||||
|
extern void *memchr(const void *, int, __kernel_size_t);
|
||||||
|
|
||||||
|
#define __HAVE_ARCH_MEMSET
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||||||
|
extern void *memset(void *, int, __kernel_size_t);
|
||||||
|
|
||||||
|
#endif
|
@ -39,10 +39,21 @@ EXPORT_SYMBOL(__copy_from_user);
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|||||||
EXPORT_SYMBOL(__copy_to_user);
|
EXPORT_SYMBOL(__copy_to_user);
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||||||
EXPORT_SYMBOL(__clear_user);
|
EXPORT_SYMBOL(__clear_user);
|
||||||
|
|
||||||
/* bitops */
|
|
||||||
#ifdef CONFIG_SMP
|
|
||||||
EXPORT_SYMBOL(__atomic_hash);
|
|
||||||
#endif
|
|
||||||
|
|
||||||
/* physical memory */
|
/* physical memory */
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||||||
EXPORT_SYMBOL(memstart_addr);
|
EXPORT_SYMBOL(memstart_addr);
|
||||||
|
|
||||||
|
/* string / mem functions */
|
||||||
|
EXPORT_SYMBOL(strchr);
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||||||
|
EXPORT_SYMBOL(strrchr);
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||||||
|
EXPORT_SYMBOL(memset);
|
||||||
|
EXPORT_SYMBOL(memcpy);
|
||||||
|
EXPORT_SYMBOL(memmove);
|
||||||
|
EXPORT_SYMBOL(memchr);
|
||||||
|
|
||||||
|
/* atomic bitops */
|
||||||
|
EXPORT_SYMBOL(set_bit);
|
||||||
|
EXPORT_SYMBOL(test_and_set_bit);
|
||||||
|
EXPORT_SYMBOL(clear_bit);
|
||||||
|
EXPORT_SYMBOL(test_and_clear_bit);
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||||||
|
EXPORT_SYMBOL(change_bit);
|
||||||
|
EXPORT_SYMBOL(test_and_change_bit);
|
||||||
|
@ -1,4 +1,6 @@
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|||||||
lib-y := bitops.o delay.o \
|
lib-y := bitops.o delay.o \
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||||||
strncpy_from_user.o strnlen_user.o clear_user.o \
|
strncpy_from_user.o strnlen_user.o clear_user.o \
|
||||||
copy_from_user.o copy_to_user.o copy_in_user.o \
|
copy_from_user.o copy_to_user.o copy_in_user.o \
|
||||||
copy_page.o clear_page.o
|
copy_page.o clear_page.o \
|
||||||
|
memchr.o memcpy.o memmove.o memset.o \
|
||||||
|
strchr.o strrchr.o
|
||||||
|
70
arch/arm64/lib/bitops.S
Normal file
70
arch/arm64/lib/bitops.S
Normal file
@ -0,0 +1,70 @@
|
|||||||
|
/*
|
||||||
|
* Based on arch/arm/lib/bitops.h
|
||||||
|
*
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* x0: bits 5:0 bit offset
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||||||
|
* bits 63:6 word offset
|
||||||
|
* x1: address
|
||||||
|
*/
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||||||
|
.macro bitop, name, instr
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||||||
|
ENTRY( \name )
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||||||
|
and x3, x0, #63 // Get bit offset
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||||||
|
eor x0, x0, x3 // Clear low bits
|
||||||
|
mov x2, #1
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||||||
|
add x1, x1, x0, lsr #3 // Get word offset
|
||||||
|
lsl x3, x2, x3 // Create mask
|
||||||
|
1: ldxr x2, [x1]
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||||||
|
\instr x2, x2, x3
|
||||||
|
stxr w0, x2, [x1]
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||||||
|
cbnz w0, 1b
|
||||||
|
ret
|
||||||
|
ENDPROC(\name )
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||||||
|
.endm
|
||||||
|
|
||||||
|
.macro testop, name, instr
|
||||||
|
ENTRY( \name )
|
||||||
|
and x3, x0, #63 // Get bit offset
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||||||
|
eor x0, x0, x3 // Clear low bits
|
||||||
|
mov x2, #1
|
||||||
|
add x1, x1, x0, lsr #3 // Get word offset
|
||||||
|
lsl x4, x2, x3 // Create mask
|
||||||
|
smp_dmb ish
|
||||||
|
1: ldxr x2, [x1]
|
||||||
|
lsr x0, x2, x3 // Save old value of bit
|
||||||
|
\instr x2, x2, x4 // toggle bit
|
||||||
|
stxr w2, x2, [x1]
|
||||||
|
cbnz w2, 1b
|
||||||
|
smp_dmb ish
|
||||||
|
and x0, x0, #1
|
||||||
|
3: ret
|
||||||
|
ENDPROC(\name )
|
||||||
|
.endm
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Atomic bit operations.
|
||||||
|
*/
|
||||||
|
bitop change_bit, eor
|
||||||
|
bitop clear_bit, bic
|
||||||
|
bitop set_bit, orr
|
||||||
|
|
||||||
|
testop test_and_change_bit, eor
|
||||||
|
testop test_and_clear_bit, bic
|
||||||
|
testop test_and_set_bit, orr
|
@ -1,5 +1,8 @@
|
|||||||
/*
|
/*
|
||||||
* Copyright (C) 2012 ARM Limited
|
* Based on arch/arm/lib/memchr.S
|
||||||
|
*
|
||||||
|
* Copyright (C) 1995-2000 Russell King
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
*
|
*
|
||||||
* This program is free software; you can redistribute it and/or modify
|
* This program is free software; you can redistribute it and/or modify
|
||||||
* it under the terms of the GNU General Public License version 2 as
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
@ -14,12 +17,28 @@
|
|||||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
*/
|
*/
|
||||||
|
|
||||||
#include <linux/kernel.h>
|
#include <linux/linkage.h>
|
||||||
#include <linux/spinlock.h>
|
#include <asm/assembler.h>
|
||||||
#include <linux/atomic.h>
|
|
||||||
|
|
||||||
#ifdef CONFIG_SMP
|
/*
|
||||||
arch_spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] __lock_aligned = {
|
* Find a character in an area of memory.
|
||||||
[0 ... (ATOMIC_HASH_SIZE-1)] = __ARCH_SPIN_LOCK_UNLOCKED
|
*
|
||||||
};
|
* Parameters:
|
||||||
#endif
|
* x0 - buf
|
||||||
|
* x1 - c
|
||||||
|
* x2 - n
|
||||||
|
* Returns:
|
||||||
|
* x0 - address of first occurrence of 'c' or 0
|
||||||
|
*/
|
||||||
|
ENTRY(memchr)
|
||||||
|
and w1, w1, #0xff
|
||||||
|
1: subs x2, x2, #1
|
||||||
|
b.mi 2f
|
||||||
|
ldrb w3, [x0], #1
|
||||||
|
cmp w3, w1
|
||||||
|
b.ne 1b
|
||||||
|
sub x0, x0, #1
|
||||||
|
ret
|
||||||
|
2: mov x0, #0
|
||||||
|
ret
|
||||||
|
ENDPROC(memchr)
|
53
arch/arm64/lib/memcpy.S
Normal file
53
arch/arm64/lib/memcpy.S
Normal file
@ -0,0 +1,53 @@
|
|||||||
|
/*
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Copy a buffer from src to dest (alignment handled by the hardware)
|
||||||
|
*
|
||||||
|
* Parameters:
|
||||||
|
* x0 - dest
|
||||||
|
* x1 - src
|
||||||
|
* x2 - n
|
||||||
|
* Returns:
|
||||||
|
* x0 - dest
|
||||||
|
*/
|
||||||
|
ENTRY(memcpy)
|
||||||
|
mov x4, x0
|
||||||
|
subs x2, x2, #8
|
||||||
|
b.mi 2f
|
||||||
|
1: ldr x3, [x1], #8
|
||||||
|
subs x2, x2, #8
|
||||||
|
str x3, [x4], #8
|
||||||
|
b.pl 1b
|
||||||
|
2: adds x2, x2, #4
|
||||||
|
b.mi 3f
|
||||||
|
ldr w3, [x1], #4
|
||||||
|
sub x2, x2, #4
|
||||||
|
str w3, [x4], #4
|
||||||
|
3: adds x2, x2, #2
|
||||||
|
b.mi 4f
|
||||||
|
ldrh w3, [x1], #2
|
||||||
|
sub x2, x2, #2
|
||||||
|
strh w3, [x4], #2
|
||||||
|
4: adds x2, x2, #1
|
||||||
|
b.mi 5f
|
||||||
|
ldrb w3, [x1]
|
||||||
|
strb w3, [x4]
|
||||||
|
5: ret
|
||||||
|
ENDPROC(memcpy)
|
57
arch/arm64/lib/memmove.S
Normal file
57
arch/arm64/lib/memmove.S
Normal file
@ -0,0 +1,57 @@
|
|||||||
|
/*
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Move a buffer from src to test (alignment handled by the hardware).
|
||||||
|
* If dest <= src, call memcpy, otherwise copy in reverse order.
|
||||||
|
*
|
||||||
|
* Parameters:
|
||||||
|
* x0 - dest
|
||||||
|
* x1 - src
|
||||||
|
* x2 - n
|
||||||
|
* Returns:
|
||||||
|
* x0 - dest
|
||||||
|
*/
|
||||||
|
ENTRY(memmove)
|
||||||
|
cmp x0, x1
|
||||||
|
b.ls memcpy
|
||||||
|
add x4, x0, x2
|
||||||
|
add x1, x1, x2
|
||||||
|
subs x2, x2, #8
|
||||||
|
b.mi 2f
|
||||||
|
1: ldr x3, [x1, #-8]!
|
||||||
|
subs x2, x2, #8
|
||||||
|
str x3, [x4, #-8]!
|
||||||
|
b.pl 1b
|
||||||
|
2: adds x2, x2, #4
|
||||||
|
b.mi 3f
|
||||||
|
ldr w3, [x1, #-4]!
|
||||||
|
sub x2, x2, #4
|
||||||
|
str w3, [x4, #-4]!
|
||||||
|
3: adds x2, x2, #2
|
||||||
|
b.mi 4f
|
||||||
|
ldrh w3, [x1, #-2]!
|
||||||
|
sub x2, x2, #2
|
||||||
|
strh w3, [x4, #-2]!
|
||||||
|
4: adds x2, x2, #1
|
||||||
|
b.mi 5f
|
||||||
|
ldrb w3, [x1, #-1]
|
||||||
|
strb w3, [x4, #-1]
|
||||||
|
5: ret
|
||||||
|
ENDPROC(memmove)
|
53
arch/arm64/lib/memset.S
Normal file
53
arch/arm64/lib/memset.S
Normal file
@ -0,0 +1,53 @@
|
|||||||
|
/*
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Fill in the buffer with character c (alignment handled by the hardware)
|
||||||
|
*
|
||||||
|
* Parameters:
|
||||||
|
* x0 - buf
|
||||||
|
* x1 - c
|
||||||
|
* x2 - n
|
||||||
|
* Returns:
|
||||||
|
* x0 - buf
|
||||||
|
*/
|
||||||
|
ENTRY(memset)
|
||||||
|
mov x4, x0
|
||||||
|
and w1, w1, #0xff
|
||||||
|
orr w1, w1, w1, lsl #8
|
||||||
|
orr w1, w1, w1, lsl #16
|
||||||
|
orr x1, x1, x1, lsl #32
|
||||||
|
subs x2, x2, #8
|
||||||
|
b.mi 2f
|
||||||
|
1: str x1, [x4], #8
|
||||||
|
subs x2, x2, #8
|
||||||
|
b.pl 1b
|
||||||
|
2: adds x2, x2, #4
|
||||||
|
b.mi 3f
|
||||||
|
sub x2, x2, #4
|
||||||
|
str w1, [x4], #4
|
||||||
|
3: adds x2, x2, #2
|
||||||
|
b.mi 4f
|
||||||
|
sub x2, x2, #2
|
||||||
|
strh w1, [x4], #2
|
||||||
|
4: adds x2, x2, #1
|
||||||
|
b.mi 5f
|
||||||
|
strb w1, [x4]
|
||||||
|
5: ret
|
||||||
|
ENDPROC(memset)
|
42
arch/arm64/lib/strchr.S
Normal file
42
arch/arm64/lib/strchr.S
Normal file
@ -0,0 +1,42 @@
|
|||||||
|
/*
|
||||||
|
* Based on arch/arm/lib/strchr.S
|
||||||
|
*
|
||||||
|
* Copyright (C) 1995-2000 Russell King
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Find the first occurrence of a character in a string.
|
||||||
|
*
|
||||||
|
* Parameters:
|
||||||
|
* x0 - str
|
||||||
|
* x1 - c
|
||||||
|
* Returns:
|
||||||
|
* x0 - address of first occurrence of 'c' or 0
|
||||||
|
*/
|
||||||
|
ENTRY(strchr)
|
||||||
|
and w1, w1, #0xff
|
||||||
|
1: ldrb w2, [x0], #1
|
||||||
|
cmp w2, w1
|
||||||
|
ccmp w2, wzr, #4, ne
|
||||||
|
b.ne 1b
|
||||||
|
sub x0, x0, #1
|
||||||
|
cmp w2, w1
|
||||||
|
csel x0, x0, xzr, eq
|
||||||
|
ret
|
||||||
|
ENDPROC(strchr)
|
43
arch/arm64/lib/strrchr.S
Normal file
43
arch/arm64/lib/strrchr.S
Normal file
@ -0,0 +1,43 @@
|
|||||||
|
/*
|
||||||
|
* Based on arch/arm/lib/strrchr.S
|
||||||
|
*
|
||||||
|
* Copyright (C) 1995-2000 Russell King
|
||||||
|
* Copyright (C) 2013 ARM Ltd.
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify
|
||||||
|
* it under the terms of the GNU General Public License version 2 as
|
||||||
|
* published by the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* This program 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 General Public License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
#include <asm/assembler.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Find the last occurrence of a character in a string.
|
||||||
|
*
|
||||||
|
* Parameters:
|
||||||
|
* x0 - str
|
||||||
|
* x1 - c
|
||||||
|
* Returns:
|
||||||
|
* x0 - address of last occurrence of 'c' or 0
|
||||||
|
*/
|
||||||
|
ENTRY(strrchr)
|
||||||
|
mov x3, #0
|
||||||
|
and w1, w1, #0xff
|
||||||
|
1: ldrb w2, [x0], #1
|
||||||
|
cbz w2, 2f
|
||||||
|
cmp w2, w1
|
||||||
|
b.ne 1b
|
||||||
|
sub x3, x0, #1
|
||||||
|
b 1b
|
||||||
|
2: mov x0, x3
|
||||||
|
ret
|
||||||
|
ENDPROC(strrchr)
|
Loading…
Reference in New Issue
Block a user