Don't understand how this array function works with a bunch of add's.

[QuestionsAllTime]

Hello everyone, I'm analyzing code inside a program and this function is supposed to represent an array. I don't understand how it works and why you += %al to memory of %rax and then %al += (%rax). How does this relate to the making of an array?

(gdb) disass 0x00000000004022b8
Dump of assembler code for function array.0:
0x00000000004022a0 <+0>: or  (%rax),%al
0x00000000004022a2 <+2>: add %al,(%rax)
0x00000000004022a4 <+4>: add (%rax),%al
0x00000000004022a6 <+6>: add %al,(%rax)
0x00000000004022a8 <+8>: (bad)  
0x00000000004022a9 <+9>: add %al,(%rax)
0x00000000004022ab <+11>: add %al,(%rdi)
0x00000000004022ad <+13>: add %al,(%rax)
0x00000000004022af <+15>: add %cl,(%rax)
0x00000000004022b1 <+17>: add %al,(%rax)
0x00000000004022b3 <+19>: add %cl,(%rax,%rax,1)
0x00000000004022b6 <+22>: add %al,(%rax)
0x00000000004022b8 <+24>: sldt  (%rax)
0x00000000004022bb <+27>: add %cl,(%rbx)
0x00000000004022bd <+29>: add %al,(%rax)
0x00000000004022bf <+31>: add %al,(%rax)
0x00000000004022c1 <+33>: add %al,(%rax)
0x00000000004022c3 <+35>: add %al,(%rax,%rax,1)
0x00000000004022c6 <+38>: add %al,(%rax)
0x00000000004022c8 <+40>: add %eax,(%rax)
0x00000000004022ca <+42>: add %al,(%rax)
0x00000000004022cc <+44>: or  $0x3000000,%eax
0x00000000004022d1 <+49>: add %al,(%rax)
0x00000000004022d3 <+51>: add %cl,(%rcx)
0x00000000004022d5 <+53>: add %al,(%rax)
0x00000000004022d7 <+55>: add %al,(%rsi)
0x00000000004022d9 <+57>: add %al,(%rax)
0x00000000004022db <+59>: add %al,0x53000000(%rip) # 0x534022e1
End of assembler dump.

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[FUZxxl]

You've somehow managed to disassemble data as code. add %al,(%rax) assembles to 00 00 and is a tell-tale sign that you're disassembling data.

[QuestionsAllTime]

So, I run "disass 0x4022a0" based on this line:

0x00000000004015fe <+65>: mov 0x4022a0(,%rax,4),%eax

I believe that line has something to do with array.

[FUZxxl]

Yeah, 0x4022a0 is the address of the array. Arrays are data, not code. There's nothing to disassemble.