Incorrect Stack Pointer Manipulation in ARM Assembly Leading to Segmentation Faults
I'm optimizing some code but I'm trying to debug I'm trying to implement I tried several approaches but none seem to work. Hey everyone, I'm running into an issue that's driving me crazy. This might be a silly question, but I'm working with a segmentation fault when trying to manipulate the stack in my ARM assembly program. The goal is to create a simple function that pushes parameters onto the stack and retrieves them correctly. However, when I attempt to access the stack pointer, it seems to point to an invalid address after the first function call. Here's the code snippet: ```assembly .global main main: sub sp, sp, #16 // Allocate space on the stack mov r0, #10 // Load parameter 10 into r0 bl my_function // Call my_function add sp, sp, #16 // Free up the stack space bx lr // Return from main my_function: str r0, [sp, #0] // Store r0 at current stack pointer mov r1, [sp, #0] // Load it back to r1 bx lr // Return from my_function ``` I've verified that the `r0` register is being loaded correctly before the call, but I suspect the stack manipulation might be incorrect. Using `add sp, sp, #16` after the call feels like it could be problematic, as it may not match the previous allocation size if things go wrong. I've tried running the code on both an ARM emulation environment and a Raspberry Pi (ARM Cortex-A72), and I'm getting the same segmentation fault. When I inspect the stack pointer in a debugger, it shows an address that is well outside the expected stack range after the function call. Could anyone guide to understand if I'm missing something in how I'm manipulating the stack around function calls, or if there are any common pitfalls in ARM assembly regarding stack management? Any pointers or corrections would be greatly appreciated! What's the best practice here? This is part of a larger service I'm building. Any ideas what could be causing this? I'm on Linux using the latest version of Assembly. I'm using Assembly 3.10 in this project. Hoping someone can shed some light on this. What would be the recommended way to handle this? Any ideas what could be causing this?