Tags: X86 ARM MIPS ARM64 ASM L1 .
What does this code do?
_a$ = 8
_f PROC
mov ecx, DWORD PTR _a$[esp-4]
mov eax, ecx
mov edx, ecx
shl edx, 16 ; 00000010H
and eax, 65280 ; 0000ff00H
or eax, edx
mov edx, ecx
and edx, 16711680 ; 00ff0000H
shr ecx, 16 ; 00000010H
or edx, ecx
shl eax, 8
shr edx, 8
or eax, edx
ret 0
_f ENDP
f PROC
MOV r1,#0xff0000
AND r1,r1,r0,LSL #8
MOV r2,#0xff00
ORR r1,r1,r0,LSR #24
AND r2,r2,r0,LSR #8
ORR r1,r1,r2
ORR r0,r1,r0,LSL #24
BX lr
ENDP
f PROC
MOVS r3,#0xff
LSLS r2,r0,#8
LSLS r3,r3,#16
ANDS r2,r2,r3
LSRS r1,r0,#24
ORRS r1,r1,r2
LSRS r2,r0,#8
ASRS r3,r3,#8
ANDS r2,r2,r3
ORRS r1,r1,r2
LSLS r0,r0,#24
ORRS r0,r0,r1
BX lr
ENDP
f:
rev w0, w0
ret
f:
srl $v0, $a0, 24
sll $v1, $a0, 24
sll $a1, $a0, 8
or $v1, $v0
lui $v0, 0xFF
and $v0, $a1, $v0
srl $a0, 8
or $v0, $v1, $v0
andi $a0, 0xFF00
jr $ra
or $v0, $a0
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