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Understanding disassembled binary from Objdump - What are the fields from the output

I get the following output when I disassembled a simple ARM binary file using the command "arm-linux-gnueabihf-objdump -d a.out"

00008480 <_start>:
8480:   f04f 0b00   mov.w   fp, #0
8484:   f04f 0e00   mov.w   lr, #0
8488:   bc02        pop {r1}
848a:   466a        mov r2, sp

What do different columns represent here? For example, 8480 and f04f 0b00 (from the 2nd line of code)

Solution

  • The first column is the address of the code in memory. 0x8480 means the memory address of this piece of code is 0x8480.

    The second column is the hex representation of the code. f04f 0b00 means from memory address 0x8480(included) to 0x8484(excluded), there are 4 bytes of code, f0, 4f, 0b, 00.

    The remaining is the disassembled code. They are disassembled from the code in second column.