/* * linux/arch/arm/lib/memcpy.S * * 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 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. */ #include <arch/asm.h> #include "asmlib.h" #define LDR1W_SHIFT 0 #define STR1W_SHIFT 0 .macro ldr1w ptr reg abort W(ldr) \reg, [\ptr], #4 .endm .macro ldr4w ptr reg1 reg2 reg3 reg4 abort ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4} .endm .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} .endm .macro ldr1b ptr reg cond=al abort ldr\cond\()b \reg, [\ptr], #1 .endm .macro str1w ptr reg abort W(str) \reg, [\ptr], #4 .endm .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8} .endm .macro str1b ptr reg cond=al abort str\cond\()b \reg, [\ptr], #1 .endm .macro enter reg1 reg2 stmdb sp!, {r0, \reg1, \reg2} .endm .macro exit reg1 reg2 ldmfd sp!, {r0, \reg1, \reg2} .endm /* Prototype: void *memcpy(void *dest, const void *src, size_t n); */ ENTRY(memcpy) 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, r0, #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 #if LDR1W_SHIFT > 0 lsl ip, ip, #LDR1W_SHIFT #endif addne pc, pc, ip @ C is always clear here b 7f 6: .rept (1 << LDR1W_SHIFT) W(nop) .endr 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 #if LDR1W_SHIFT < STR1W_SHIFT lsl ip, ip, #STR1W_SHIFT - LDR1W_SHIFT #elif LDR1W_SHIFT > STR1W_SHIFT lsr ip, ip, #LDR1W_SHIFT - STR1W_SHIFT #endif add pc, pc, ip nop .rept (1 << STR1W_SHIFT) W(nop) .endr 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, r0, #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 ENDPROC(memcpy)