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21 lines
519 B
ArmAsm
21 lines
519 B
ArmAsm
.file "memmove.S"
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.section .text
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.global _memmove
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.type _memmove,@function
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_memmove:
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mov r1, r4 ; Save a copy of DEST
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cmp r1, r2
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blt 2f ; If SRC (r2) is less than DEST (r1) then copy backwards
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smovf
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1:
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mov r4, r1 ; Return DEST
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rts
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2:
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add r3, r1 ; The SMOVB instructions requires the DEST in r1 and the
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add r3, r2 ; SRC in r2 but it needs them to point the last bytes of
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sub #1, r2 ; the regions involved not the first bytes, hence these
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sub #1, r1 ; additions and subtractions.
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smovb
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bra 1b
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