Questions tagged [64-bit]
A 64-bit architecture is usually a system where addresses (pointers) are 64 bits wide. Sometimes, it can mean a system where the “natural” size for integer computations (the word size) is 64 bits.
64-bit
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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 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 ...
- 21
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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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51
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Assembly jump instructions don't seem to work
bits 64
default rel
section .data
fmt db "%s", 0xd, 0xa, 0
err db "Correct usage: echo <string>"
section .text
extern printf
extern ExitProcess
global ...
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Order in which instructions are printed/executed
Why the output is in diffrent order than it is declared?
Shouldnt the output be in this order?
aaaa
bbbb
cccc
Instead it is:
I assume the issue is in assigning "bbb" value to the text ...
- 23
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REX encoding for instructions with the VEX prefix
[x64]
is there some generic algorithm using which I can determine relevant registers for the rex byte? I'm specifically interested in the calculation of REX for instructions with the VEX prefix (so ...
- 69
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What is the difference between these two functions in x64 assembly?
I'm playing around with lower level stuff in C on Windows (x64) to try and learn low level concepts. I ran across something I don't understand and just wonder if someone could explain something to me....
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Writing x64 nasm assembly for windows [duplicate]
I would like to learn how to write x64 nasm assembly for windows but I can't find any resources for that.
And also how to compile the assembly into executable program.
So if anyone knows of a ...
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VB,net cannot assign the number 18446744073709551615 to a Uint64 or Uint128 [closed]
In a tool of my I run into this very high number what seems to be a uInt64.
So, I thought if I'm using a uInt128 it should work but is also generate an overflow.
How I can overcome this?
Kind regards,
...
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Excel VBA 32-Bit to 64-Bit
I have a old Excel file with 32-bit code.
Who can turn this into 64-Bit code?
Private Declare Function SetWindowPos Lib "user32" ( _
ByVal hWnd As Long, _
...
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Spec file for a 64-bit DLL wine wrapper
Trying to create a spec file for a WINE wrapper for a Windows 64-bit DLL.
In a 32-bit equivalent project the spec file might have contained something like this:
@ stdcall foo (long ptr) Proxyfoo
In ...
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how to convert windows filetime 64bit hex to date and time?
i have this reg_binary (5D-07-BB-CB-60-1F-D7-01) value of the shutdowntime from the registry how to convert it to this format (DDMMYYYY HH:MM:SS)? enter image description here
is there a simple way to ...
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0
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WinExec not executing command - return value 0 (MASM in Visual Studio 2022)
When calling WinExec and passing the two variables to it (as per MSDN):
UINT WinExec(
[in] LPCSTR lpCmdLine,
[in] UINT uCmdShow
);
I can't seem to get a correct value returned in RAX and the ...
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Why symbolic access to x64 assembly function parameters stopped to work from MSVC2013
I needed to catch parameters of function written in x64 assembly. First 4 parameters are stored in registry. They are fine.
It seems that it was possible to use symbolic address as depicted in example....
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updating 32bit macro for 64bit
This excel macro worked fine on windows 10, but gives me errors on windows 11. If anyone could help would really appreciate it.
Option Explicit
Private Declare Function URLDownloadToFile Lib "...
