gojasm

The jazzy JAS compiler.

Usage instructions

Invoke the compiler using:

$ gojasm input.jas -o output.ijvm

To see the selection of useful (and useless) flags use:

$ gojasm --help

IJVM extensions

gojasm has a few extensions on the JAS language specification, just for ease of use:

• numbers: gojasm allows you to define numbers using either normal (10), hex (0x10), octal (012), and binary (0b1010), instead of only the normal form
• #print macro: gojasm has a macro, #print "text to print" which will be converted to the corresponding BIPUSH and OUT instructions.

Custom IJVM configuration

By default we load the equivalent to the Mic-1 default configuration file, which is defined as:

0x10    BIPUSH byte
0x59    DUP
0xA7    GOTO label
0x60    IADD
0x7E    IAND
0x99    IFEQ label
0x9B    IFLT label
0x9F    IF_ICMPEQ label
0x84    IINC var byte
0x15    ILOAD var
0xB6    INVOKEVIRTUAL method
0xB0    IOR
0xAC    IRETURN
0x36    ISTORE var
0x64    ISUB
0x13    LDC_W constant
0x00    NOP
0x57    POP
0x5F    SWAP
0xC4    WIDE
0xFF    HALT
0xFE    ERR
0xFD    OUT
0xFC    IN

You can extend this file with as many instructions as you would like. Every line follows the pattern:

opcode name [args...]

The following arguments types are available:

• byte (a single byte)
• var (name of a variable)
• label (a label)
• constant (name of a constant)
• method (name of a method)

There can be any numer of arguments. However, there is a maximum of only one of either label or constant per operation.

To use your custom configuration, invoke gojasm like follows:

$ gojasm -c custom.conf input.jas -o output.jas