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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RET to the main flow after execution of a conditional
Is there any possibility to use RET function to go back from the conditional statement to the main function (_start) where it was called from and go on with the next instructions?
Right now, it's just ...
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Why CSAPP say Gcc do not use vcvtss2sd?
Computer Systems: A Programmer's Perpective (3rd), in section 3.11.1, say "Suppose the low-order 4 bytes of %xmm0 hold a single-precision value; then it would seem straightforward to use the ...
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Why does operand 1 in a modr/m byte change depending on the decoding mode
I'm trying to figure out why the instruction changes from add [eax], al to add [rax], al when changing the decoding mode from x86 to x64.
The instruction bytes are 00 00
I think it might be because ...
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Web.Config Redirect for Azure.Core not working as expected
I have a Microsoft Web Site project (different than a Web Application) that has version 1.20.0.0 of Azure.Core.dll as an assembly in the project. However, a .cs file in the project is calling for ...
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function call crash on amd [closed]
I made a exe and a dll. Dll calling function in exe. it is fine in intel system but it is crash when amd system.
asm
{
push ebp -> crash here most of the time
mov esp,ebp -> crash here rarely
...
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How to use UART in PIC16F877A with assembly code?
I am using UART in PIC16F877A with test board HJ-5G.
My oscillator is 4MHz (KDS4.000). I tried to receive data from my computer.(Serial Debug Assistant)
But I do not receive anything. And I tried to ...
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Can i boot from sram when i use arm cortex m3
normally,we boot from flash or ROM, but what if i want to boot from SRAM area(0x20000000_0x3fffffff) instead of Code area(0x00000000_0x1fffffff), should i use startup.s to copy the code to SRAM area?
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Twice as slow SIMD performance without extra copy
I've been optimizing some code, and stumbled across some peculiar case.
Here are the two assembly codes:
; FAST
lea rcx,[rsp+50h]
call qword ptr [Random_get_float3] ;this function ...
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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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