disassembly

来源： https://stackoverflow.com/questions/40685938/differentiate-data-from-instructions-in-arm

来源： https://stackoverflow.com/questions/40685938/differentiate-data-from-instructions-in-arm

来源： https://stackoverflow.com/questions/14807033/nasm-changes-jnz-to-jne-while-assembling-why

来源： https://stackoverflow.com/questions/15502403/where-do-i-find-the-assembly-code-for-a-procedure-called-in-the-gcc-assembly-out

来源： https://stackoverflow.com/questions/15502403/where-do-i-find-the-assembly-code-for-a-procedure-called-in-the-gcc-assembly-out

来源： https://stackoverflow.com/questions/62341879/why-gdb-shows-different-addresses-in-rip-relative-mode-from-absolute-address

问题 I'm trying to understand the lines in a piece of disassembled code as shown below. I'd like to know the following: dec %eax : Why is the eax register being decremented? What is the initial value of the eax register? movl $0x0,-0x8(%ebp) : Why are we moving the value 0x0 onto the stack? Doesn't movl store a 32-bit value (4 bytes)? If so, why is the value being stored 8 bytes below the base pointer instead of 4 bytes? Here's the disassembled binary: Contents of section .text: 0000 554889e5

问题 I'm trying to understand the lines in a piece of disassembled code as shown below. I'd like to know the following: dec %eax : Why is the eax register being decremented? What is the initial value of the eax register? movl $0x0,-0x8(%ebp) : Why are we moving the value 0x0 onto the stack? Doesn't movl store a 32-bit value (4 bytes)? If so, why is the value being stored 8 bytes below the base pointer instead of 4 bytes? Here's the disassembled binary: Contents of section .text: 0000 554889e5

问题 I'm studying the x86 assembly language. In order to better understand what's going on behind the scenes of string creation, I have a sample program that just prints a string. GCC produced the following Assembly program, and I'm having trouble understanding the compiler's output: Assembly Code: Dump of assembler code for function main: 0x0000000000400596 <+0>: push %rbp 0x0000000000400597 <+1>: mov %rsp,%rbp 0x000000000040059a <+4>: sub $0x10,%rsp 0x000000000040059e <+8>: movq $0x400668,-0x8(

问题 Let's say I've the following set of instructions: 00E79E00 | E8 AE580000 CALL someprocess.00E7F6B3 00E79E05 | 85C0 TEST EAX, EAX (output taken from OllyDbg) How do I encode the rel32 offset from the near call(0xE8) so I can get the absolute position I can jump to? I know that the offset is relative to the next instruction and is calculated by subtracting the target with it. My question is: how do I 'reverse' this so I get the function addres 00E7F6B3 from the relative offset AE580000 回答1: You