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4d1e7918aa
Optimise code to use efficient unaligned memory access which is available on ARCv2. This allows us to really simplify memcpy code and speed up the code one and a half times (in case of unaligned source or destination). Don't wire it up yet ! Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
48 lines
1009 B
ArmAsm
48 lines
1009 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0+ */
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/*
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* ARCv2 memcpy implementation optimized for unaligned memory access using.
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*
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* Copyright (C) 2019 Synopsys
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* Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
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*/
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#include <linux/linkage.h>
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#ifdef CONFIG_ARC_HAS_LL64
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# define LOADX(DST,RX) ldd.ab DST, [RX, 8]
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# define STOREX(SRC,RX) std.ab SRC, [RX, 8]
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# define ZOLSHFT 5
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# define ZOLAND 0x1F
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#else
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# define LOADX(DST,RX) ld.ab DST, [RX, 4]
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# define STOREX(SRC,RX) st.ab SRC, [RX, 4]
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# define ZOLSHFT 4
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# define ZOLAND 0xF
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#endif
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ENTRY_CFI(memcpy)
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mov r3, r0 ; don;t clobber ret val
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lsr.f lp_count, r2, ZOLSHFT
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lpnz @.Lcopy32_64bytes
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;; LOOP START
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LOADX (r6, r1)
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LOADX (r8, r1)
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LOADX (r10, r1)
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LOADX (r4, r1)
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STOREX (r6, r3)
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STOREX (r8, r3)
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STOREX (r10, r3)
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STOREX (r4, r3)
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.Lcopy32_64bytes:
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and.f lp_count, r2, ZOLAND ;Last remaining 31 bytes
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lpnz @.Lcopyremainingbytes
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;; LOOP START
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ldb.ab r5, [r1, 1]
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stb.ab r5, [r3, 1]
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.Lcopyremainingbytes:
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j [blink]
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END_CFI(memcpy)
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