65 lines
1.3 KiB
ArmAsm
65 lines
1.3 KiB
ArmAsm
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/* SPDX-License-Identifier: GPL-2.0 */
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#include <linux/linkage.h>
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#include <asm/asm.h>
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ENTRY(__memmove)
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WEAK(memmove)
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move t0, a0
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move t1, a1
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beq a0, a1, exit_memcpy
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beqz a2, exit_memcpy
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srli t2, a2, 0x2
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slt t3, a0, a1
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beqz t3, do_reverse
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andi a2, a2, 0x3
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li t4, 1
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beqz t2, byte_copy
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word_copy:
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lw t3, 0(a1)
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addi t2, t2, -1
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addi a1, a1, 4
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sw t3, 0(a0)
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addi a0, a0, 4
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bnez t2, word_copy
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beqz a2, exit_memcpy
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j byte_copy
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do_reverse:
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add a0, a0, a2
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add a1, a1, a2
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andi a2, a2, 0x3
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li t4, -1
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beqz t2, reverse_byte_copy
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reverse_word_copy:
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addi a1, a1, -4
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addi t2, t2, -1
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lw t3, 0(a1)
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addi a0, a0, -4
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sw t3, 0(a0)
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bnez t2, reverse_word_copy
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beqz a2, exit_memcpy
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reverse_byte_copy:
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addi a0, a0, -1
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addi a1, a1, -1
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byte_copy:
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lb t3, 0(a1)
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addi a2, a2, -1
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sb t3, 0(a0)
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add a1, a1, t4
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add a0, a0, t4
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bnez a2, byte_copy
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exit_memcpy:
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move a0, t0
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move a1, t1
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ret
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END(__memmove)
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