/* Copyright (C) 2006, 2008, 2009 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, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include /* * 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 /* * 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. */ ENTRY(memmove) subs ip, r0, r1 cmphi r2, ip #ifdef NOT_IN_libc bls memcpy #else bls HIDDEN_JUMPTARGET(memcpy) #endif stmfd sp!, {r0, r4, lr} cfi_adjust_cfa_offset (12) cfi_rel_offset (r4, 4) cfi_rel_offset (lr, 8) cfi_remember_state 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} 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( 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} cfi_adjust_cfa_offset (-16) cfi_restore (r5) cfi_restore (r6) cfi_restore (r7) cfi_restore (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] #if defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__) ldmfd sp!, {r0, r4, lr} cfi_adjust_cfa_offset (-12) cfi_restore (r4) cfi_restore (lr) bx lr #else ldmfd sp!, {r0, r4, pc} #endif cfi_restore_state 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} 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 (r9, 16) 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} cfi_adjust_cfa_offset (-20) cfi_restore (r5) cfi_restore (r6) cfi_restore (r7) cfi_restore (r8) cfi_restore (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 END(memmove) libc_hidden_builtin_def (memmove)