Top "X86-64" questions

x86-64 is a 64 bit extension to the Intel x86 architecture

Why did GCC generate mov %eax,%eax and what does it mean?

GCC 4.4.3 generated the following x86_64 assembly. The part that confuses me is the mov %eax,%eax. Move the register to …

gcc assembly x86-64
Libtool think that a "library was moved" but it isn't the case

I am currently recompiling gtk+ and dependencies from source (I have no other choices). All my custom packages are installed …

gtk libtool freetype pango x86-64
What is the purpose of the "PAUSE" instruction in x86?

I am trying to create a dumb version of a spin lock. Browsing the web, I came across a assembly …

parallel-processing x86 x86-64 intel critical-section
Why is %eax zeroed before a call to printf?

I am trying to pick up a little x86. I am compiling on a 64bit mac with gcc -S -O0. …

macos assembly gcc x86-64 calling-convention
Assembly 64bit - movl, movq. Interchanging is okay?

Context: Learning GAS assembly on 64 bit linux. Many tutorials are for 32-bit assembly. Difficult to bushwhack through x86_64 assembly. Question: …

assembly 64-bit x86-64 gnu-assembler instructions
Why 64 bit mode ( Long mode ) doesn't use segment registers?

I'm a beginner level of student :) I'm studying about intel architecture, and I'm studying a memory management such as a …

memory-management x86-64 intel memory-segmentation
What is the 'shadow space' in x64 assembly?

I found plenty of topics about this shadow space, but I couldn't find the answer in none of them, so …

windows assembly x86-64 calling-convention abi
Function parameters transferred in registers on 64bit OS?

I am reading one of Agner Fog's manuals and as an advantage for 64 bit Operating Systems (over 32 bit) he says: …

c++ c assembly x86-64 calling-convention
Do shared libraries use the same heap as the application?

Say I have an application in Linux that uses shared libraries (.so files). My question is whether the code in …

c linux gcc x86-64
Which inline assembly code is correct for rdtscp?

Disclaimer: Words cannot describe how much I detest AT&T style syntax I have a problem that I hope …

gcc assembly x86-64 inline-assembly