Flat Assembler is a fast and efficient self-assembling 80x86 assembler. It supports x86 and x86-64 instruction sets with MMX, 3DNow!, SSE up to SSE4, AVX, AVX2, and XOP extensions. It can produce output in binary, MZ, PE, COFF, or ELF format. It includes powerful but easy-to-use macroinstruction support and does multiple passes to optimize the instruction codes for size. It is written entirely in assembly language.
Yasm is a complete rewrite of the NASM assembler. It currently supports the x86 and AMD64 instruction sets, accepts NASM and GAS assembler syntaxes, outputs binary, ELF32, ELF64, COFF, Mach-O (32 and 64), RDOFF2, Win32, and Win64 object formats, and generates source debugging information in STABS, DWARF 2, and CodeView 8 formats.
An almost ISO C compatible C compiler that produces binaries for 6502-based computers. Targets that are supported out of the box are: Apple ][, Atari 8-bit machines, Commodore C64/C128/C16/C116, Commodore Plus/4, Commodore 600/700, GEOS for C64, and Lynx. The package includes a complete suite of assembler development tools (assembler, linker, archiver) which allows mixing of C and assembler code.
Nonpareil is a microcode-level simulator for HP calculators introduced between 1972 and 1982, including the HP-35, HP-45, HP-55, HP-25, HP-34C, HP-38C, HP-41CV, HP-11C, HP-12C, HP-15C, HP-16C, and other models. The necessary microcode is included, as is a microcode assembler. The GTK+ toolkit is used for the user interface.
The Amsterdam Compiler Kit is a fully-featured retargetable compiler toolchain. It will cross-compile ANSI C, K&R C, Pascal, Modula-2, Occam, Fortran and Basic for a number of architectures including, but not limited to, the 6500, 68000, Z80, i80, i86, i386, and PDP-11. It provides a complete development environment including preprocessors, compilers, assemblers, linkers, librarian tools, and target download tools.