Simulizer allows you to write assembly code and run it on a simulated and visualised CPU. It has been designed to improve various features of SPIM.

User Guide

Final Report (contains a more in depth description)

Features

• A code editor with syntax highlighting for the MIPS language, along with real-time error checking and tooltips.
• Simulation and visualisation of an abstract simplified CPU.
• A window showing the values of the registers as programs are running.
• Interaction with the CPU, e.g. controlling the clock speed, pausing, stepping through execution, etc.
• Helpful messages and animations as the simulation is running to help the user understand how the CPU is operating.
• High-level visualisation of annotated programs, see below.

Running

Package dependencies to run on a 64 bit Debian based GNU/Linux System (eg Ubuntu)

• openjdk-8-jre
• openjfx (JavaFX for openJDK-8)
• libxslt1.1 (usually installed anyway)

Windows

• Java 8 JRE
  • also includes JavaFX

Screenshots

Example Algorithm Visualisation:

Example Pipeline Visualisation:

Example CPU Visualisation:

Annotations

Simulizer uses a JavaScript engine along side the CPU emulation. Javascript code is placed between @{ and }@ delimiters inside MIPS comments. The JavaScript code can access information about the current state of the CPU (eg registers, memory etc) and can be used to:

• signal 'high level' algorithm visualisations (eg integer lists: swapping elements and highlighting elements, tower of Hanoi: disk swapping, bitmap rendering of memory location etc)
• prototype complex code before transcribing to assembly
• debugging tool (very useful for printf debugging or conditional breakpoints)

High-Level Visualiation

The current data structures/graphics that can be visualised are:

• Lists
• Tower of Hanoi
• Canvas (complete access to a JavaFX canvas)
  • can be used to render a bitmap of memory locations
  • can be used to draw any shapes
  • can be used to create your own high level visualisations from Javascript!

MIPS Cross Compiling C(++)

It is possible to use a compiler to generate MIPS output which Simulizer can consume (with some automatic editing). See work/gcc-mips.sh for a script which uses gcc to cross compile for MIPS (the gcc cross compiler must be installed manually).

This is how some of the more elaborate examples (eg snake.s) were created.

Building

Package dependencies to build on a 64 bit Debian based GNU/Linux System (eg Ubuntu)

• openjdk-8-jdk
• spim (for compatiability tests)
• openjfx (JavaFX for openJDK-8)
• gradle (or use gradle plugin with an IDE or the gradlew wrapper)
• add /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/ext/jfxrt.jar to the SDK classpath
  • your placement might be different. try: find /usr -name 'jfxrt.jar'
  • in Intellij IDEA: File > Project Structure > SDKs > 1.8 > Classpath
• gradle will handle the rest of the dependencies

Meet the Team

Charlie Street	Kelsey McKenna	Matthew Broadway	Michael Oultram	Theo Styles

Licence

Simulizer is released under the GNU General Public License v3.0