32 lines
705 B
ArmAsm
32 lines
705 B
ArmAsm
.file "memcpy.S"
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.section .text
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.global _memcpy
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.type _memcpy,@function
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_memcpy:
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#ifdef __RX_DISALLOW_STRING_INSNS__
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/* Do not use the string instructions - they might prefetch
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bytes from outside of valid memory. This is particularly
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dangerous in I/O space. */
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;; FIXME: It would be more space efficient to just branch to _memmove...
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cmp #0, r3 ; If the count is zero, do nothing
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beq 1f
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mov r1, r14 ; Save a copy of DEST
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2: mov.b [r2+], r5
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mov.b r5, [r14+]
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sub #1, r3
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bne 2b
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1: rts
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#else
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mov r1, r4 ; Save a copy of DEST
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smovf ; Copy R2 (source) to R1 (dest). Stop after R3 bytes.
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mov r4, r1 ; Return DEST
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rts
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#endif
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.size _memcpy, . - _memcpy
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