Pyssembly

A python assembly emulator.

This tool allows to execute pseudo assembly code and it is meant for teaching purposes.

Install

python -m pip install pyssembly

Usage

python -m pyssembly <code.pys>

Examples

Lots of examples are available in the examples folder.

Print the result of 137 * 2322:

1. create file multiplication.pys containing:

mov a 137
mul a 2322
out a "\n"

2. run it with: python -m pyssembly multiplication.pys
3. result: 318114

Read 2 numbers from stdin and return average:

1. create file average.pys containing:

in a "First number: "
in b "Second number: "
int a a 
int b b 
mov avg a
add avg b
div avg 2
out "The average between " a 
out " and " b 
out " is: " avg 
out "\n" null

2. run it with: python -m pyssembly average.pys
3. result:

First number: 26
Second number: 17
The average between 26 and 17 is: 21.5

Pseudo assembly

The language that pyssembly is able to execute is a pseudo assembly. All instructions have the form:

<instruction> <operand a> <operand b>

All instructions that return a result, store such result in the first operand (a).

Comments

To comment a line write ';' at the beginning. For example:

;this is a comment

Labels

To label a line, to use it as destination in a jmp statement, simply write a single word in the line. For example:

this-is-a-label

Null

The null value is simply the keyword null. Like so:

out "Hello world" null

Arrays

Arrays are accessed using the [] sintax. For example:

mov arr[0] 6

Arrays are actually dictionaries and anything can be a key.

Instruction set

General

• mov a b: store b into a
• jmp a b: if a, jump to b (b can be a label or a line number)
• in a b: print b to stdout, read string from stdin, store it into a
• out a b: print a and b to stdout

Conversions

• bool a b: boolean(b)
• int a b: integer(b)
• flt a b: float(b)
• str a b: string(b)

Math

• add a b: a + b
• sub a b: a - b
• mul a b: a * b
• div a b: a / b
• pow a b: a^b
• log a b: log_b^a
• root a b: a^1/b
• idiv a b: a // b
• mod a b: a % b

Random

• rnd a b: generate random float, a<=rf<=b
• irnd a b: generate random integer, a<=ri<=b

Trigonometry

• sin a b: sin(b)
• cos a b: cos(b)
• tan a b: tan(b)
• asin a b: asin(b)
• acos a b: acos(b)
• atan a b: atan(b)
• atan2 a b: atan2(a, b)

Boolean

• eq a b: a == b
• neq a b: a != b
• les a b: a < b
• leq a b: a <= b
• grt a b: a > b
• geq a b: a >= b
• not a b: not b
• and a b: a and b
• or a b: a or b
• xor a b: a xor b
• nand a b: a nand b
• nor a b: a nor b
• nxor a b: a nxor b