How to compile assembly code with NASM
Compiling assembly code involves translating human-readable assembly code into machine code or object code that a computer can execute.
Compilation Process
- Assembler: The first step is to use an assembler to convert assembly code into machine code or object code. Assemblers are specific to the architecture of the target machine.
- Linker: If the program consists of multiple source files or relies on external libraries, a linker may be used to combine these files into a single executable. The linker resolves addresses and references between different parts of the code.
Consider a simple x86 assembly program that prints "Hello, World!" to the console:
Assembling
Use an assembler (e.g., NASM for x86) to convert the assembly code into object code:
This produces an object file (hello.o) containing machine code.
Linking
If needed, use a linker (e.g., ld for Linux) to link the object file with any necessary libraries:
This produces the final executable (hello), ready to be executed.
Execution
Run the compiled executable:
The program will execute and print "Hello, World!" to the console.
Conclusion
Compiling assembly code involves using an assembler to convert human-readable assembly code into machine code or object code, and optionally using a linker to combine multiple object files into a single executable.