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+/* Copyright (C) 2006-2014 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 *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
+
+ push {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( sfi_pld r1, #-4 )
+ 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( sbcsne r4, ip, r2 ) @ C is always set here
+ CALGN( bcs 2f )
+ CALGN( adr r4, 6f )
+ CALGN( subs r2, r2, ip ) @ C is set here
+#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( sfi_pld r1, #-4 )
+2: PLD( subs r2, r2, #96 )
+ PLD( sfi_pld r1, #-32 )
+ PLD( blt 4f )
+ PLD( sfi_pld r1, #-64 )
+ PLD( sfi_pld r1, #-96 )
+
+3: PLD( sfi_pld r1, #-128 )
+4: sfi_breg r1, \
+ ldmdb \B!, {r3, r4, r5, r6, r7, r8, ip, lr}
+ subs r2, r2, #32
+ sfi_breg r0, \
+ stmdb \B!, {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
+ sfi_breg r1, \
+ ldr r3, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr r4, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr r5, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr r6, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr r7, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr r8, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r1, \
+ ldr lr, [\B, #-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
+ sfi_breg r0, \
+ str r3, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str r4, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str r5, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str r6, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str r7, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str r8, [\B, #-4]!
+ .p2align ARM_BX_ALIGN_LOG2
+ sfi_breg r0, \
+ str lr, [\B, #-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
+ sfi_breg r1, \
+ ldrbne r3, [\B, #-1]!
+ sfi_breg r1, \
+ ldrbcs r4, [\B, #-1]!
+ sfi_breg r1, \
+ ldrbcs ip, [\B, #-1]
+ sfi_breg r0, \
+ strbne r3, [\B, #-1]!
+ sfi_breg r0, \
+ strbcs r4, [\B, #-1]!
+ sfi_breg r0, \
+ strbcs ip, [\B, #-1]
+
+#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: cmp ip, #2
+ sfi_breg r1, \
+ ldrbgt r3, [\B, #-1]!
+ sfi_breg r1, \
+ ldrbge r4, [\B, #-1]!
+ sfi_breg r1, \
+ ldrb lr, [\B, #-1]!
+ sfi_breg r0, \
+ strbgt r3, [\B, #-1]!
+ sfi_breg r0, \
+ strbge r4, [\B, #-1]!
+ subs r2, r2, ip
+ sfi_breg r0, \
+ strb lr, [\B, #-1]!
+ blt 8b
+ ands ip, r1, #3
+ beq 1b
+
+10: bic r1, r1, #3
+ cmp ip, #2
+ sfi_breg r1, \
+ ldr r3, [\B, #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( 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( sfi_pld r1, #-4 )
+ PLD( subs r2, r2, #96 )
+ PLD( sfi_pld r1, #-32 )
+ PLD( blt 13f )
+ PLD( sfi_pld r1, #-64 )
+ PLD( sfi_pld r1, #-96 )
+
+12: PLD( sfi_pld r1, #-128 )
+13: sfi_breg r1, \
+ ldmdb \B!, {r7, r8, r10, ip}
+ mov lr, r3, PUSH #\push
+ subs r2, r2, #32
+ sfi_breg r1, \
+ ldmdb \B!, {r3, r4, r5, r6}
+ orr lr, lr, ip, PULL #\pull
+ mov ip, ip, PUSH #\push
+ orr ip, ip, r10, PULL #\pull
+ mov r10, r10, PUSH #\push
+ orr r10, r10, 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
+ sfi_breg r0, \
+ stmdb \B!, {r4 - r8, r10, ip, lr}
+ 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 lr, r3, PUSH #\push
+ sfi_breg r1, \
+ ldr r3, [\B, #-4]!
+ subs ip, ip, #4
+ orr lr, lr, r3, PULL #\pull
+ sfi_breg r0, \
+ str lr, [\B, #-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)