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Update memory-layout and calling-convention reading materials to correctly reflect the 64-bit System V AMD64 ABI. Add the missing `xor rax, rax` before variadic function calls and convert 32-bit stack argument examples to 64-bit register arguments. Fix #141 Signed-off-by: alexf05 <alexfechet16@gmail.com>
Correct multiple issues introduced during the x86_64 transition: - max-c-calls: Fix signedness comparison by using `jae` and fix pointer initialization bug in the solution. Revert support file. - regs-preserve: Add required 16-byte stack alignment before calling printf and fix the order of stack restoration in the solution. Fix #141 Signed-off-by: alexf05 <alexfechet16@gmail.com>
Signed-off-by: alexf05 <alexfechet16@gmail.com>
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Description of changes
This PR resolves the remaining bugs, ABI violations, and typos from the x86_64 transition in
lab-09.Specific fixes include:
raxfor variadic functions likeprintfand updating 32-bit stack argument examples to 64-bit register arguments).max-c-calls: Fixed a logical bug by changing the signed comparison (jge) to unsigned (jae). Fixed pointer initialization in the solution.regs-preserve: Added the required 16-byte stack alignment (sub rsp, 8) to the support code before callingprintfto prevent immediate segfaults. Corrected the stack restoration order (pop rbxvsadd rsp, 8) in the solution.Question for Reviewer (@teodutu): I noticed that the
max-c-calls-x86task currently contains 64-bit code instead of 32-bit, and themax-assembly-calls-x86task is missingadd esp, Xstack cleanups for thecdeclcalling convention. Should I convert these files back to proper 32-bit assembly in a follow-up commit, or are these x86 legacy folders planned for deletion?Fix #141