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-rw-r--r--arch/arm/lib/Makefile5
-rw-r--r--arch/arm/lib/copy_template.S255
-rw-r--r--arch/arm/lib/memcpy.S410
-rw-r--r--arch/arm/lib/memmove.S206
4 files changed, 502 insertions, 374 deletions
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index d3d9b21..8f9770f 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -7,8 +7,9 @@
lib-y := backtrace.o changebit.o csumipv6.o csumpartial.o \
csumpartialcopy.o csumpartialcopyuser.o clearbit.o \
copy_page.o delay.o findbit.o memchr.o memcpy.o \
- memset.o memzero.o setbit.o strncpy_from_user.o \
- strnlen_user.o strchr.o strrchr.o testchangebit.o \
+ memmove.o memset.o memzero.o setbit.o \
+ strncpy_from_user.o strnlen_user.o \
+ strchr.o strrchr.o testchangebit.o \
testclearbit.o testsetbit.o uaccess.o \
getuser.o putuser.o clear_user.o \
ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \
diff --git a/arch/arm/lib/copy_template.S b/arch/arm/lib/copy_template.S
new file mode 100644
index 0000000..838e435
--- /dev/null
+++ b/arch/arm/lib/copy_template.S
@@ -0,0 +1,255 @@
+/*
+ * linux/arch/arm/lib/copy_template.s
+ *
+ * Code template for optimized memory copy functions
+ *
+ * Author: Nicolas Pitre
+ * Created: Sep 28, 2005
+ * Copyright: MontaVista Software, Inc.
+ *
+ * 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 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...)
+
+/*
+ * Theory of operation
+ * -------------------
+ *
+ * This file provides the core code for a forward memory copy used in
+ * the implementation of memcopy(), copy_to_user() and copy_from_user().
+ *
+ * The including file must define the following accessor macros
+ * according to the need of the given function:
+ *
+ * ldr1w ptr reg abort
+ *
+ * This loads one word from 'ptr', stores it in 'reg' and increments
+ * 'ptr' to the next word. The 'abort' argument is used for fixup tables.
+ *
+ * ldr4w ptr reg1 reg2 reg3 reg4 abort
+ * ldr8w ptr, reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ *
+ * This loads four or eight words starting from 'ptr', stores them
+ * in provided registers and increments 'ptr' past those words.
+ * The'abort' argument is used for fixup tables.
+ *
+ * ldr1b ptr reg cond abort
+ *
+ * Similar to ldr1w, but it loads a byte and increments 'ptr' one byte.
+ * It also must apply the condition code if provided, otherwise the
+ * "al" condition is assumed by default.
+ *
+ * str1w ptr reg abort
+ * str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ * str1b ptr reg cond abort
+ *
+ * Same as their ldr* counterparts, but data is stored to 'ptr' location
+ * rather than being loaded.
+ *
+ * enter reg1 reg2
+ *
+ * Preserve the provided registers on the stack plus any additional
+ * data as needed by the implementation including this code. Called
+ * upon code entry.
+ *
+ * exit reg1 reg2
+ *
+ * Restore registers with the values previously saved with the
+ * 'preserv' macro. Called upon code termination.
+ */
+
+
+ enter r4, lr
+
+ 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)
+ stmfd sp!, {r5 - r8}
+ blt 5f
+
+ CALGN( ands ip, r1, #31 )
+ CALGN( rsb r3, ip, #32 )
+ CALGN( sbcnes r4, r3, r2 ) @ C is always set here
+ CALGN( bcs 2f )
+ CALGN( adr r4, 6f )
+ CALGN( subs r2, r2, r3 ) @ C gets set
+ CALGN( add pc, r4, ip )
+
+ 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: ldr8w r1, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f
+ subs r2, r2, #32
+ str8w r0, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f
+ bge 3b
+ PLD( cmn r2, #96 )
+ PLD( bge 4b )
+
+5: ands ip, r2, #28
+ rsb ip, ip, #32
+ addne pc, pc, ip @ C is always clear here
+ b 7f
+6: nop
+ ldr1w r1, r3, abort=20f
+ ldr1w r1, r4, abort=20f
+ ldr1w r1, r5, abort=20f
+ ldr1w r1, r6, abort=20f
+ ldr1w r1, r7, abort=20f
+ ldr1w r1, r8, abort=20f
+ ldr1w r1, lr, abort=20f
+
+ add pc, pc, ip
+ nop
+ nop
+ str1w r0, r3, abort=20f
+ str1w r0, r4, abort=20f
+ str1w r0, r5, abort=20f
+ str1w r0, r6, abort=20f
+ str1w r0, r7, abort=20f
+ str1w r0, r8, abort=20f
+ str1w r0, lr, abort=20f
+
+ CALGN( bcs 2b )
+
+7: ldmfd sp!, {r5 - r8}
+
+8: movs r2, r2, lsl #31
+ ldr1b r1, r3, ne, abort=21f
+ ldr1b r1, r4, cs, abort=21f
+ ldr1b r1, ip, cs, abort=21f
+ str1b r0, r3, ne, abort=21f
+ str1b r0, r4, cs, abort=21f
+ str1b r0, ip, cs, abort=21f
+
+ exit r4, pc
+
+9: rsb ip, ip, #4
+ cmp ip, #2
+ ldr1b r1, r3, gt, abort=21f
+ ldr1b r1, r4, ge, abort=21f
+ ldr1b r1, lr, abort=21f
+ str1b r0, r3, gt, abort=21f
+ str1b r0, r4, ge, abort=21f
+ subs r2, r2, ip
+ str1b r0, lr, abort=21f
+ blt 8b
+ ands ip, r1, #3
+ beq 1b
+
+10: bic r1, r1, #3
+ cmp ip, #2
+ ldr1w r1, lr, abort=21f
+ 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( sbcnes r4, ip, r2 ) @ C is always set here
+ CALGN( subcc r2, r2, ip )
+ CALGN( bcc 15f )
+
+11: stmfd sp!, {r5 - r9}
+
+ 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: ldr4w r1, r4, r5, r6, r7, abort=19f
+ mov r3, lr, pull #\pull
+ subs r2, r2, #32
+ ldr4w r1, r8, r9, ip, lr, abort=19f
+ 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, r9, push #\push
+ mov r9, r9, pull #\pull
+ orr r9, r9, ip, push #\push
+ mov ip, ip, pull #\pull
+ orr ip, ip, lr, push #\push
+ str8w r0, r3, r4, r5, r6, r7, r8, r9, ip, , abort=19f
+ bge 12b
+ PLD( cmn r2, #96 )
+ PLD( bge 13b )
+
+ ldmfd sp!, {r5 - r9}
+
+14: ands ip, r2, #28
+ beq 16f
+
+15: mov r3, lr, pull #\pull
+ ldr1w r1, lr, abort=21f
+ subs ip, ip, #4
+ orr r3, r3, lr, push #\push
+ str1w r0, r3, abort=21f
+ 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
+
+
+/*
+ * Abort preanble and completion macros.
+ * If a fixup handler is required then those macros must surround it.
+ * It is assumed that the fixup code will handle the private part of
+ * the exit macro.
+ */
+
+ .macro copy_abort_preamble
+19: ldmfd sp!, {r5 - r9}
+ b 21f
+20: ldmfd sp!, {r5 - r8}
+21:
+ .endm
+
+ .macro copy_abort_end
+ ldmfd sp!, {r4, pc}
+ .endm
+
diff --git a/arch/arm/lib/memcpy.S b/arch/arm/lib/memcpy.S
index f5a593c..7e71d67 100644
--- a/arch/arm/lib/memcpy.S
+++ b/arch/arm/lib/memcpy.S
@@ -1,393 +1,59 @@
/*
* linux/arch/arm/lib/memcpy.S
*
- * Copyright (C) 1995-1999 Russell King
+ * Author: Nicolas Pitre
+ * Created: Sep 28, 2005
+ * Copyright: MontaVista Software, Inc.
*
- * 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.
- *
- * ASM optimised string functions
+ * 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.
*/
+
#include <linux/linkage.h>
#include <asm/assembler.h>
- .text
-
-#define ENTER \
- mov ip,sp ;\
- stmfd sp!,{r0,r4-r9,fp,ip,lr,pc} ;\
- sub fp,ip,#4
-
-#define EXIT \
- LOADREGS(ea, fp, {r0, r4 - r9, fp, sp, pc})
-
-#define EXITEQ \
- LOADREGS(eqea, fp, {r0, r4 - r9, fp, sp, pc})
-
-/*
- * Prototype: void memcpy(void *to,const void *from,unsigned long n);
- */
-ENTRY(memcpy)
-ENTRY(memmove)
- ENTER
- cmp r1, r0
- bcc 23f
- subs r2, r2, #4
- blt 6f
- PLD( pld [r1, #0] )
- ands ip, r0, #3
- bne 7f
- ands ip, r1, #3
- bne 8f
+ .macro ldr1w ptr reg abort
+ ldr \reg, [\ptr], #4
+ .endm
-1: subs r2, r2, #8
- blt 5f
- subs r2, r2, #20
- blt 4f
- PLD( pld [r1, #28] )
- PLD( subs r2, r2, #64 )
- PLD( blt 3f )
-2: PLD( pld [r1, #60] )
- PLD( pld [r1, #92] )
- ldmia r1!, {r3 - r9, ip}
- subs r2, r2, #32
- stmgeia r0!, {r3 - r9, ip}
- ldmgeia r1!, {r3 - r9, ip}
- subges r2, r2, #32
- stmia r0!, {r3 - r9, ip}
- bge 2b
-3: PLD( ldmia r1!, {r3 - r9, ip} )
- PLD( adds r2, r2, #32 )
- PLD( stmgeia r0!, {r3 - r9, ip} )
- PLD( ldmgeia r1!, {r3 - r9, ip} )
- PLD( subges r2, r2, #32 )
- PLD( stmia r0!, {r3 - r9, ip} )
-4: cmn r2, #16
- ldmgeia r1!, {r3 - r6}
- subge r2, r2, #16
- stmgeia r0!, {r3 - r6}
- adds r2, r2, #20
- ldmgeia r1!, {r3 - r5}
- subge r2, r2, #12
- stmgeia r0!, {r3 - r5}
-5: adds r2, r2, #8
- blt 6f
- subs r2, r2, #4
- ldrlt r3, [r1], #4
- ldmgeia r1!, {r4, r5}
- subge r2, r2, #4
- strlt r3, [r0], #4
- stmgeia r0!, {r4, r5}
+ .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
+ ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
+ .endm
-6: adds r2, r2, #4
- EXITEQ
- cmp r2, #2
- ldrb r3, [r1], #1
- ldrgeb r4, [r1], #1
- ldrgtb r5, [r1], #1
- strb r3, [r0], #1
- strgeb r4, [r0], #1
- strgtb r5, [r0], #1
- EXIT
+ .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
+ .endm
-7: rsb ip, ip, #4
- cmp ip, #2
- ldrb r3, [r1], #1
- ldrgeb r4, [r1], #1
- ldrgtb r5, [r1], #1
- strb r3, [r0], #1
- strgeb r4, [r0], #1
- strgtb r5, [r0], #1
- subs r2, r2, ip
- blt 6b
- ands ip, r1, #3
- beq 1b
+ .macro ldr1b ptr reg cond=al abort
+ ldr\cond\()b \reg, [\ptr], #1
+ .endm
-8: bic r1, r1, #3
- ldr r7, [r1], #4
- cmp ip, #2
- bgt 18f
- beq 13f
- cmp r2, #12
- blt 11f
- PLD( pld [r1, #12] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 10f )
- PLD( pld [r1, #28] )
-9: PLD( pld [r1, #44] )
-10: mov r3, r7, pull #8
- ldmia r1!, {r4 - r7}
- subs r2, r2, #16
- orr r3, r3, r4, push #24
- mov r4, r4, pull #8
- orr r4, r4, r5, push #24
- mov r5, r5, pull #8
- orr r5, r5, r6, push #24
- mov r6, r6, pull #8
- orr r6, r6, r7, push #24
- stmia r0!, {r3 - r6}
- bge 9b
- PLD( cmn r2, #32 )
- PLD( bge 10b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 12f
-11: mov r3, r7, pull #8
- ldr r7, [r1], #4
- subs r2, r2, #4
- orr r3, r3, r7, push #24
- str r3, [r0], #4
- bge 11b
-12: sub r1, r1, #3
- b 6b
+ .macro str1w ptr reg abort
+ str \reg, [\ptr], #4
+ .endm
-13: cmp r2, #12
- blt 16f
- PLD( pld [r1, #12] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 15f )
- PLD( pld [r1, #28] )
-14: PLD( pld [r1, #44] )
-15: mov r3, r7, pull #16
- ldmia r1!, {r4 - r7}
- subs r2, r2, #16
- orr r3, r3, r4, push #16
- mov r4, r4, pull #16
- orr r4, r4, r5, push #16
- mov r5, r5, pull #16
- orr r5, r5, r6, push #16
- mov r6, r6, pull #16
- orr r6, r6, r7, push #16
- stmia r0!, {r3 - r6}
- bge 14b
- PLD( cmn r2, #32 )
- PLD( bge 15b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 17f
-16: mov r3, r7, pull #16
- ldr r7, [r1], #4
- subs r2, r2, #4
- orr r3, r3, r7, push #16
- str r3, [r0], #4
- bge 16b
-17: sub r1, r1, #2
- b 6b
+ .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
+ stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
+ .endm
-18: cmp r2, #12
- blt 21f
- PLD( pld [r1, #12] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 20f )
- PLD( pld [r1, #28] )
-19: PLD( pld [r1, #44] )
-20: mov r3, r7, pull #24
- ldmia r1!, {r4 - r7}
- subs r2, r2, #16
- orr r3, r3, r4, push #8
- mov r4, r4, pull #24
- orr r4, r4, r5, push #8
- mov r5, r5, pull #24
- orr r5, r5, r6, push #8
- mov r6, r6, pull #24
- orr r6, r6, r7, push #8
- stmia r0!, {r3 - r6}
- bge 19b
- PLD( cmn r2, #32 )
- PLD( bge 20b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 22f
-21: mov r3, r7, pull #24
- ldr r7, [r1], #4
- subs r2, r2, #4
- orr r3, r3, r7, push #8
- str r3, [r0], #4
- bge 21b
-22: sub r1, r1, #1
- b 6b
+ .macro str1b ptr reg cond=al abort
+ str\cond\()b \reg, [\ptr], #1
+ .endm
+ .macro enter reg1 reg2
+ stmdb sp!, {r0, \reg1, \reg2}
+ .endm
-23: add r1, r1, r2
- add r0, r0, r2
- subs r2, r2, #4
- blt 29f
- PLD( pld [r1, #-4] )
- ands ip, r0, #3
- bne 30f
- ands ip, r1, #3
- bne 31f
+ .macro exit reg1 reg2
+ ldmfd sp!, {r0, \reg1, \reg2}
+ .endm
-24: subs r2, r2, #8
- blt 28f
- subs r2, r2, #20
- blt 27f
- PLD( pld [r1, #-32] )
- PLD( subs r2, r2, #64 )
- PLD( blt 26f )
-25: PLD( pld [r1, #-64] )
- PLD( pld [r1, #-96] )
- ldmdb r1!, {r3 - r9, ip}
- subs r2, r2, #32
- stmgedb r0!, {r3 - r9, ip}
- ldmgedb r1!, {r3 - r9, ip}
- subges r2, r2, #32
- stmdb r0!, {r3 - r9, ip}
- bge 25b
-26: PLD( ldmdb r1!, {r3 - r9, ip} )
- PLD( adds r2, r2, #32 )
- PLD( stmgedb r0!, {r3 - r9, ip} )
- PLD( ldmgedb r1!, {r3 - r9, ip} )
- PLD( subges r2, r2, #32 )
- PLD( stmdb r0!, {r3 - r9, ip} )
-27: cmn r2, #16
- ldmgedb r1!, {r3 - r6}
- subge r2, r2, #16
- stmgedb r0!, {r3 - r6}
- adds r2, r2, #20
- ldmgedb r1!, {r3 - r5}
- subge r2, r2, #12
- stmgedb r0!, {r3 - r5}
-28: adds r2, r2, #8
- blt 29f
- subs r2, r2, #4
- ldrlt r3, [r1, #-4]!
- ldmgedb r1!, {r4, r5}
- subge r2, r2, #4
- strlt r3, [r0, #-4]!
- stmgedb r0!, {r4, r5}
+ .text
-29: adds r2, r2, #4
- EXITEQ
- cmp r2, #2
- ldrb r3, [r1, #-1]!
- ldrgeb r4, [r1, #-1]!
- ldrgtb r5, [r1, #-1]!
- strb r3, [r0, #-1]!
- strgeb r4, [r0, #-1]!
- strgtb r5, [r0, #-1]!
- EXIT
+/* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
-30: cmp ip, #2
- ldrb r3, [r1, #-1]!
- ldrgeb r4, [r1, #-1]!
- ldrgtb r5, [r1, #-1]!
- strb r3, [r0, #-1]!
- strgeb r4, [r0, #-1]!
- strgtb r5, [r0, #-1]!
- subs r2, r2, ip
- blt 29b
- ands ip, r1, #3
- beq 24b
-
-31: bic r1, r1, #3
- ldr r3, [r1], #0
- cmp ip, #2
- blt 41f
- beq 36f
- cmp r2, #12
- blt 34f
- PLD( pld [r1, #-16] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 33f )
- PLD( pld [r1, #-32] )
-32: PLD( pld [r1, #-48] )
-33: mov r7, r3, push #8
- ldmdb r1!, {r3, r4, r5, r6}
- subs r2, r2, #16
- orr r7, r7, r6, pull #24
- mov r6, r6, push #8
- orr r6, r6, r5, pull #24
- mov r5, r5, push #8
- orr r5, r5, r4, pull #24
- mov r4, r4, push #8
- orr r4, r4, r3, pull #24
- stmdb r0!, {r4, r5, r6, r7}
- bge 32b
- PLD( cmn r2, #32 )
- PLD( bge 33b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 35f
-34: mov ip, r3, push #8
- ldr r3, [r1, #-4]!
- subs r2, r2, #4
- orr ip, ip, r3, pull #24
- str ip, [r0, #-4]!
- bge 34b
-35: add r1, r1, #3
- b 29b
-
-36: cmp r2, #12
- blt 39f
- PLD( pld [r1, #-16] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 38f )
- PLD( pld [r1, #-32] )
-37: PLD( pld [r1, #-48] )
-38: mov r7, r3, push #16
- ldmdb r1!, {r3, r4, r5, r6}
- subs r2, r2, #16
- orr r7, r7, r6, pull #16
- mov r6, r6, push #16
- orr r6, r6, r5, pull #16
- mov r5, r5, push #16
- orr r5, r5, r4, pull #16
- mov r4, r4, push #16
- orr r4, r4, r3, pull #16
- stmdb r0!, {r4, r5, r6, r7}
- bge 37b
- PLD( cmn r2, #32 )
- PLD( bge 38b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 40f
-39: mov ip, r3, push #16
- ldr r3, [r1, #-4]!
- subs r2, r2, #4
- orr ip, ip, r3, pull #16
- str ip, [r0, #-4]!
- bge 39b
-40: add r1, r1, #2
- b 29b
+ENTRY(memcpy)
-41: cmp r2, #12
- blt 44f
- PLD( pld [r1, #-16] )
- sub r2, r2, #12
- PLD( subs r2, r2, #32 )
- PLD( blt 43f )
- PLD( pld [r1, #-32] )
-42: PLD( pld [r1, #-48] )
-43: mov r7, r3, push #24
- ldmdb r1!, {r3, r4, r5, r6}
- subs r2, r2, #16
- orr r7, r7, r6, pull #8
- mov r6, r6, push #24
- orr r6, r6, r5, pull #8
- mov r5, r5, push #24
- orr r5, r5, r4, pull #8
- mov r4, r4, push #24
- orr r4, r4, r3, pull #8
- stmdb r0!, {r4, r5, r6, r7}
- bge 42b
- PLD( cmn r2, #32 )
- PLD( bge 43b )
- PLD( add r2, r2, #32 )
- adds r2, r2, #12
- blt 45f
-44: mov ip, r3, push #24
- ldr r3, [r1, #-4]!
- subs r2, r2, #4
- orr ip, ip, r3, pull #8
- str ip, [r0, #-4]!
- bge 44b
-45: add r1, r1, #1
- b 29b
+#include "copy_template.S"
diff --git a/arch/arm/lib/memmove.S b/arch/arm/lib/memmove.S
new file mode 100644
index 0000000..ef7fddc
--- /dev/null
+++ b/arch/arm/lib/memmove.S
@@ -0,0 +1,206 @@
+/*
+ * linux/arch/arm/lib/memmove.S
+ *
+ * Author: Nicolas Pitre
+ * Created: Sep 28, 2005
+ * Copyright: (C) MontaVista Software Inc.
+ *
+ * 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.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * 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...)
+
+ .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. This
+ * is a transposition of the code from copy_template.S but with the copy
+ * occurring in the opposite direction.
+ */
+
+ENTRY(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
+ PLD( pld [r1, #-4] )
+ bne 9f
+ ands ip, r1, #3
+ bne 10f
+
+1: subs r2, r2, #(28)
+ stmfd sp!, {r5 - r8}
+ blt 5f
+
+ CALGN( ands ip, r1, #31 )
+ CALGN( sbcnes r4, ip, r2 ) @ C is always set here
+ CALGN( bcs 2f )
+ CALGN( adr r4, 6f )
+ CALGN( subs r2, r2, ip ) @ C is set here
+ CALGN( add pc, r4, ip )
+
+ PLD( pld [r1, #-4] )
+2: PLD( subs r2, r2, #96 )
+ PLD( pld [r1, #-32] )
+ PLD( blt 4f )
+ PLD( pld [r1, #-64] )
+ PLD( pld [r1, #-96] )
+
+3: PLD( pld [r1, #-128] )
+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
+ PLD( cmn r2, #96 )
+ PLD( bge 4b )
+
+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]!
+
+ CALGN( bcs 2b )
+
+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]
+ ldmfd sp!, {r0, r4, pc}
+
+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
+
+ CALGN( ands ip, r1, #31 )
+ CALGN( rsb ip, ip, #32 )
+ CALGN( sbcnes r4, ip, r2 ) @ C is always set here
+ CALGN( subcc r2, r2, ip )
+ CALGN( bcc 15f )
+
+11: stmfd sp!, {r5 - r9}
+
+ PLD( pld [r1, #-4] )
+ PLD( subs r2, r2, #96 )
+ PLD( pld [r1, #-32] )
+ PLD( blt 13f )
+ PLD( pld [r1, #-64] )
+ PLD( pld [r1, #-96] )
+
+12: PLD( pld [r1, #-128] )
+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
+ PLD( cmn r2, #96 )
+ PLD( bge 13b )
+
+ 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
+ CALGN( cmp r2, #0 )
+ CALGN( bge 11b )
+
+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
+
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