Questions tagged [assembly]
Assembly language questions. Please tag the processor and/or the instruction set you are using, as well as the assembler, a valid set should be like this: ([assembly] [x86] [gnu-assembler] or [att]). Use the [.net-assembly] tag instead for .NET assemblies, [cil] for .NET assembly language, [wasm] for web assembly, and for Java bytecode, use the tag java-bytecode-asm instead.
assembly
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When an embedded c program is created, why is there extra machine code around my compiled c program?
This C program blinks an LED attached to an AVR ATmega32u4.
ISR(TIMER1_OVF_vect) // attach Interrupt Sub Routine to TIMER1
{
// toggle LED
PIND = (1 << PIND5); // #define PIND (*(...
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Difference between comiss and comisd in x64 asm
I wrote some code to compare the value of xmm10 and xmm6 using:
comiss xmm10, xmm6 and then comisd xmm10, xmm6
The first one works, and the second one doesn't.
I tried using subss xmm10, xmm6 followed ...
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Why is my array value not equal to a literal?
I am new to assembly and was trying to work with an array. However, I was geting caught when try to compare the array value to a constant stored in a register.
From the following code I was expecting ...
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Printing 2D array in MIPS
I have been using a few other posts on here to try and figure out what I am doing wrong but I am stuck and could use some help. I am making a game that has an 8x8 "board" (2d array) similar ...
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What is wrong with this control for the brightness of a lamp in ATmega328P?
I'm new to assembly and I'm trying to develop a control for the brightness of a lamp for my college. The lamp must have 5 distinct levels of brightness, one off and four levels with gradual increase. ...
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signal SIGSEGV: address access protected in __run_exit_handlers
I'm trying to do a packer project for my school, it is made in C and ASM, and for the moment it is supposed to target only ELF files.
I have managed to do my section injection, correctly align my new ...
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CMake does not compile asm-files (cross-compile)
We set up our build system with CMake and besides C and C++-files we need to compile asm-files (.s).
We use a tiarmclang-compiler (LTS3.2.0) and thus need to crosscompile.
While everything works for C ...
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multidimensional slice access performance in golang
I am working on a little and simple game-of-life in Golang and stumbled on a performance problem during slice access.
This is the primary data structure for the game:
type Neighbor struct {
X, Y ...
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Why does gdb combine byte values when examining memory as words? [closed]
While examining 4 addresses from $rip as bytes in GDB, it shows 4 individual values. However, when I examine the same addresses as words, it combines that 4 byte values into a single word value. Why ...
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NASM ORG doesn't like SECTION [closed]
Looks like NASM ORG directive doesn't behave correctly in the presence of SECTION directive, in spite that it's compiled to the binary format. I wonder if there's an alternative for ORG in NASM which ...
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I'm trying to build a nand2tetris assembler but the ply.lex library in python keep breaking my assembly instructions to different lines
the first thought I had was that I didn't manage to handle the new line character properly because it keeps throwing the new line character "\n" whenever I try to append the instructions for ...
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Unable to compile NASM without -no_pie on macOS
I'm trying to follow the tutorial for NASM and I made a few adjustments (like changing the entrypoint function from "start" to "_main") to get the following hello.asm to compile ...
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data segment of AVR store nonsense after compiling
So i'm trying to change the first element of an array that i'm storing in sram and i checked if the data after compile is equal to the value of pre-initialaztion and it wasn't equal. so this my code:
....
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Why do I keep getting a Segmentation Fault from trying to access /dev/mem in ARM64 on the Raspberry Pi 4?
I've been working at this program for months, and I've fixed many errors, errors with alignment, other segmentation faults, and I've gotten down to this one, where it throws a segmentation fault when ...
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gnu inline assembly constraint `i` for memory address
Recetly, this function rip_rel_ptr has been added to Linux kernel.
https://elixir.bootlin.com/linux/latest/source/arch/x86/include/asm/asm.h#L118.
I can compile the kernel, but when I copy this ...
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