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d2912cb15b
Based on 2 normalized pattern(s): 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 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 # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
68 lines
1.4 KiB
ArmAsm
68 lines
1.4 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*/
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/* If dst and src are 4 byte aligned, copy 8 bytes at a time.
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If the src is 4, but not 8 byte aligned, we first read 4 bytes to get
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it 8 byte aligned. Thus, we can do a little read-ahead, without
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dereferencing a cache line that we should not touch.
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Note that short and long instructions have been scheduled to avoid
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branch stalls.
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The beq_s to r3z could be made unaligned & long to avoid a stall
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there, but the it is not likely to be taken often, and it
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would also be likey to cost an unaligned mispredict at the next call. */
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#include <linux/linkage.h>
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ENTRY_CFI(strcpy)
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or r2,r0,r1
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bmsk_s r2,r2,1
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brne.d r2,0,charloop
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mov_s r10,r0
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ld_s r3,[r1,0]
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mov r8,0x01010101
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bbit0.d r1,2,loop_start
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ror r12,r8
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sub r2,r3,r8
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bic_s r2,r2,r3
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tst_s r2,r12
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bne r3z
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mov_s r4,r3
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.balign 4
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loop:
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ld.a r3,[r1,4]
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st.ab r4,[r10,4]
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loop_start:
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ld.a r4,[r1,4]
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sub r2,r3,r8
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bic_s r2,r2,r3
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tst_s r2,r12
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bne_s r3z
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st.ab r3,[r10,4]
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sub r2,r4,r8
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bic r2,r2,r4
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tst r2,r12
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beq loop
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mov_s r3,r4
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#ifdef __LITTLE_ENDIAN__
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r3z: bmsk.f r1,r3,7
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lsr_s r3,r3,8
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#else
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r3z: lsr.f r1,r3,24
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asl_s r3,r3,8
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#endif
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bne.d r3z
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stb.ab r1,[r10,1]
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j_s [blink]
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.balign 4
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charloop:
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ldb.ab r3,[r1,1]
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brne.d r3,0,charloop
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stb.ab r3,[r10,1]
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j [blink]
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END_CFI(strcpy)
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