How Do You Make An Assembler?

Question

I'd like to make a simple x86 assembler. I'm wondering if there's any tutorials for making your own assembler. Or if there's a simple assembler that I could study.

Also, I wonder what tools are used in looking at and handling the binary/hex of programs.

Answer 1

As far as example code goes...

• http://www.nasm.us/
• http://www.gnu.org/software/binutils/

I don't know of any "simple" assemblers, though.

Answer 2

I wrote one a long time ago. It is as simple as getting the x86 assembler ref guide from Intel, and writing the bytes to a .com file (for windows). I wish i could find my old forum post I made on it. It was written in D++. Just goes to show you can do it in any language. Just tokenize your string and translate it.

Answer 3

This is what you are looking for:

Assemblers And Loaders - By David Salomon. Published February, 1993 - Freely available (download here)

Ofcourse you are going to need:

1. Intel® 64 and IA-32 Architectures Software Developer's Manuals
2. AMD-64 Architecture Programmers manual
3. Linkers and Loaders by John R. Levine (freely available)
4. ELF File Format Specifications : System V ABI Update
5. Microsoft Portable Executable and Common Object File Format Specification

You can always refer to implementations of Opensource Assemblers

1. Netwide Assembler (NASM)
2. Gnu Assembler (GAS)