Tags: X86 ARM MIPS ARM64 ASM L1 .
What does this code do?
An array of array[x][y] form is accessed here. Try to determine the dimensions of the array, at least partially, by finding y.
_array$ = 8
_x$ = 12
_y$ = 16
_f PROC
mov eax, DWORD PTR _x$[esp-4]
mov edx, DWORD PTR _y$[esp-4]
mov ecx, eax
shl ecx, 4
sub ecx, eax
lea eax, DWORD PTR [edx+ecx*8]
mov ecx, DWORD PTR _array$[esp-4]
fld QWORD PTR [ecx+eax*8]
ret 0
_f ENDP
f PROC
RSB r1,r1,r1,LSL #4
ADD r0,r0,r1,LSL #6
ADD r1,r0,r2,LSL #3
LDM r1,{r0,r1}
BX lr
ENDP
f PROC
MOVS r3,#0xf
LSLS r3,r3,#6
MULS r1,r3,r1
ADDS r0,r1,r0
LSLS r1,r2,#3
ADDS r1,r0,r1
LDM r1,{r0,r1}
BX lr
ENDP
f:
sxtw x1, w1
add x0, x0, x2, sxtw 3
lsl x2, x1, 10
sub x1, x2, x1, lsl 6
ldr d0, [x0,x1]
ret
f:
sll $v0, $a1, 10
sll $a1, 6
subu $a1, $v0, $a1
addu $a1, $a0, $a1
sll $a2, 3
addu $a1, $a2
lwc1 $f0, 4($a1)
or $at, $zero
lwc1 $f1, 0($a1)
jr $ra
or $at, $zero
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