All Questions
971
questions
1
vote
1
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50
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My bootloader isn't printing after switching to Protected Mode
I'm trying to print the character "C" after switching to the Protected Mode, but it isn't working, and I don't know why. I'm using Assembly AT&T/GAS syntax
Here is the code:
.code16
....
user26135221
1
vote
0
answers
55
views
Whis is this x86_64 AT&T assembly failing, i think foo: is the culprit?
Here is the assembly, I am using Windows 11.
Assembling: as .\test.S -o test.out
Linking: ld -o test.exe -subsys=console test.out -L "C:\TDM-GCC-64\x86_64-w64-mingw32\lib" -lmsvcrt
When i ...
- 86
0
votes
0
answers
100
views
cannot execute: required file not found, linking -lc wth ld command
So basically, I am working on a compiler ... long story short, I codegen and i want to use libc with the x86_64 AT&T Assembly. The object file is generated with 64bit elf architecture. I want to ...
- 86
0
votes
0
answers
79
views
Problem with program in assembly x86 AT&T, division by repeated subtraction algorithm
I have a problem with my program. It should read from STDIN 32 bytes as divident, then next 32 bytes as divisor, after that it should divide divident by divisor using "division by repeated ...
- 1
1
vote
2
answers
42
views
Problem to convert from ASCII to integers in Assembly AT&T 32 bit
ASM newbie here. I'm trying to convert in ASM AT&T (32-bit version) the following ASCII text from ASCII to integer (skipping the commas (44 in ASCII) and newlines (10 in ASCII)):
1,10,2,2\n2,7,6,7\...
- 11
2
votes
1
answer
74
views
GNU as: when to use '$'
After a long time I have to use the GNU assembler again. Ever since I had trouble with the '$'.
The manual just says:
3.6.2.1 Integers
A decimal integer starts with a non-zero digit followed by zero ...
- 61
1
vote
0
answers
48
views
GAS with AT&T syntax - creating a label by concatenating a variable of a macro
I have an assembly code that generates ISR (interrupt service routine) stubs. I want to automate this process, and for each of the interrupts (there are 256) generate it's own unique stub. This is ...
1
vote
0
answers
52
views
x86 Assembly: handling exponent 1 in power calculation
I have this code I wrote in x86. The code does a power of the first number I'm pushing to the queue by the second one.
Now all cases work as expected except one case that's when the second number ...
- 129
0
votes
1
answer
123
views
Breakpoints for assembly code in VSCode with GDB
I use xUbuntu 22.04.4 and the VSCode current version for linux (1.87.2)
I want to set the debugging of a .s assembly (AT&T) file. I created a task.json and a launch.json file and allowed ...
- 337
0
votes
0
answers
15
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jle instruction failed to jump properly [duplicate]
I am writing a bubble sort algorithm, and here is my code, using AT&T format, x86-64.
.section .data
values:
.int 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
.section .text
.globl _start
_start:
movl $...
- 1
1
vote
1
answer
34
views
Loading disk sector into memory (AT&T)
I want to load a sector into a memory address starting at (0xD000). I use index addressing to complete disk load with 0x13 BIOS interrupt. Using 16bit mode, BIOS, AT& Syntax assembly.
I am having ...
0
votes
0
answers
26
views
Are these two x86_64 assembly programs the same? [duplicate]
I'm on an Ubuntu 22.04 x86_64 system, kernel 6.5.0-15-generic. I'm learning how to make simple programs that make system calls by using GAS AT&T assembly format. My goal was to create a simple ...
- 55
0
votes
1
answer
312
views
Hello World x86_64. Is this 100% correct?
I'm on an Ubuntu 22.04 x86_64 system, kernel 6.5.0-15-generic.
I'm learning how to make simple programs that make system calls by using GAS AT&T assembly format.
This assembly program is in the ...
- 55
0
votes
1
answer
91
views
How do I go about creating a GAS AT&T format main assembly program that uses the syscall instruction to print "Hello World"?
I'm on a Linux x86_64 system and my goal is to create an assembly program inside the classic main function. I've tried this and it works fine :
.code64
.section .rodata
msg: .ascii "Hello, World!\...
- 55
0
votes
0
answers
50
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AT&T Assembly how to compare Strings from console
I have the string "-l" stored in a variable called lineSpace and I want to check if its equal to a value which I get from the console arguments.
I try to get the first part of the argument ...
