sgadrat/6502-compilers-bench

6502 C compilers benchmark

Easing the way to compare code generated by cc65, 6502-gcc, vbcc, and KickC.

This repository contains scripts to:

Compile the same source with various 6502 compilers,

Show the code generated,

Emulate generated binaries,

Show performance information.

Running benchs

Setuping your environement

Dependencies

You will need an up and running installation of:

cc65: mandatory, benchmarks for all compilers use CA65 assembler
Python: highly recomended, automation scripts are written in Python
gcc or clang: to build the emulator that run banchmarks

If you want to benchmark extra emulators, you will need them ready to compile some source:

6502-gcc: clone and compile it from there: https://github.com/itszor/gcc-6502-bits
vbcc

Build the emulator

The emulator is necessary to run benchmarks. It is not a NES/C64/AppleII/... emulator, it has its own expectations about memory layout.

$ cd emulator/
$ g++ -Imos6502 emulator.cpp mos6502/mos6502.cpp -o emulator

You should now have an executable named emulator in the emulator/ folder.

Setting your environment variables

Automation scripts heavily rely on environment variables to find compilers.

Note: you can skip any *_BIN if you have the binary in your PATH

Always needed:

$ export CA65_BIN=/somewhere/cc65/bin/ca65
$ export LD65_BIN=/somewhere/cc65/bin/ld65

Needed for benching cc65:

$ export C65_BIN=/somewhere/cc65/bin/cc65
$ export CC65_LIB=/somewhere/cc65/lib

Needed for benching vbcc:

$ export VBCC=/somewhere/vbcc6502/vbcc6502_linux/vbcc
$ export VBCC_BIN=/somewhere/vbcc6502/vbcc6502_linux/vbcc/bin/vc

Needed for benching 6502-gcc:

$ export GCC6502_BIN=/somewhere/gcc-6502-bits/prefix/bin/6502-gcc

Needed for benching KickC:

$ export KICKC_BIN=/somewhere/kickc/bin/kickc.sh

Running a benchmark

Running the unzip bench with cc65:

compilers/cc65/bench code_samples/unzip/unzip.c code_samples/unzip/unzip_data.s

This will produce a fat json on standard output. It contains:

The number of cycles taken by the generated code

The size of the generated code

The memory dump after execution

The generated assembler

You may add --options="-Oirs" to pass these flags to the compiler.

You may add --verbose to have compiler commands being print before executing them.

All compilers/*/bench scripts share the same comand line interface. Feel free to run the same test with different compilers.

Impacting environment variables

CA65_BIN: path to ca65 binary (default: ca65 [aka search in PATH])

CC65_BIN: path to cc65 binary (default: cc65 [aka search in PATH])

LD65_BIN: path to ld65 binary (default: ld65 [aka search in PATH])

CC65_LIB: path where cc65's standard *.lib can be found (default: tries to link without --lib-path, doomed to fail)

GCC6502_BIN: path to 6502-gcc binary (default: 6502-gcc [aka search in PATH])

VBCC_BIN: vc binary from VBCC toolchain (default: vc [aka search in PATH])

VBCC: shall point to VBCC's root dir for vbcc compilation to work

KICKC_BIN: path to kickc.sh (or equivalent for your platform) (default: kickc.sh [aka search in PATH])

EMU65: path to the emulator compiled from the emulator/ dir

sgadrat / 6502-compilers-bench