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Are there any different assembly languages for x86?
The topic of x86 assembly language programming is messy because: There are many different assemblers out there: MASM, NASM, gas, as86, TASM, a86, Terse, etc. All use radically different assembly languages. There are differences in the way you have to code for Linux, OS/X, Windows, etc. Many different object file formats exist: ELF, COFF, Win32,
What are in and out instructions in x86 used for?
Speculative prefetch of uncacheable memory isn’t allowed in the x86 ISA. And can’t ever happen for I/O space accesses. But in / out are very slow and partially serializing, and physical memory address space is no longer scarce, so device memory is normally just memory-mapped for efficient access with full-size PCIe transactions.)
Are there different object file formats for x86?
Many different object file formats exist: ELF, COFF, Win32, OMF, a.out for Linux, a.out for FreeBSD, rdf, IEEE-695, as86, etc. You generally will be calling functions residing in the operating system or other libraries so you will have to know some technical details about how libraries are linked, and not all linkers work the same way.
How are assembly language files assembled in a linker?
Regardless of the assembler, object file format, linker or operating system you use, the programming process is always the same: Each assembly language file is assembled into an “object file” and the object files are linked with other object files to form an executable.
Can a C function be called from an assembly function?
It doesn’t just have to be Assembly and C. The first step to calling an assembly function from C is to package it as a static library. Create a function and then compile the assembly source to an object file. We will link that later when we compile the c program.
Can you compile a c file into an assembly file?
Whether you compile the object files from Assembly or from C they turn out the same. Once they are object files they can be called from anywhere, but they have to be defined as externals and linked. You could create static libraries as object files from other languages too.