MIPT-MIPS / MIPT-V

MIPT-MIPS / MIPT-V is a pre-silicon simulator of MIPS and RISC-V CPU. It measures performance of program running on CPU, thus taking best features of RTL and common functional simulation:

• Precision. We provide cycle-accurate models of branch prediction unit and pipeline behavior.
• Customization. Cache size, branch prediction algorithms, and other parameters can be easily changed.
• Simplicity. Our source files are much more readable than RTL.
• Speed. Up to 1.0 MHz simulation frequency on i5-7300U.

MIPT-MIPS can be used for different purposes:

• Performance control of software optimizations: you may check IPC boosts of your programs
• Pathfinding of hardware optimizations: you may easily integrate some nice feature to CPU model
• Performance control of developed or produced hardware
• Education: simulator is a nice experimental frog to study CPU internals

Key system-level features:

• Compatibility with MARS system calls convention
• Interactive simulation with GDB

Key microarchitecture features:

• Configurable branch prediction unit with 5 prediction algorithms
• Configurable instruction cache with true-LRU policy
• Interstage data bypassing

More details about internals are available on Wiki

Requirements

We use C++17 features and Boost 1.61. Thus, you have to use compilers of these versions or newer:

• GCC 7
• Clang 5.0
• Apple LLVM 7.3.0
• MS Visual Studio 2017 (Boost 1.66 and CMake 3.10.2 are required)

Install Boost before building the project.

To work with MIPS traces, you need to install MIPS binutils. Please follow our manual if you are using Linux, OS X, or Windows.

Our build system is CMake. You should install CMake 3.9 or higher. Check our Wiki page to get more details about CMake. Users of IDE (Visual Studio, Eclipse, CodeBlocks etc.) may generate project files with CMake as well.

To generate RISC-V opcodes, CMake uses Python. Python interpreter should be available in your environment. If you still use Python 2, be sure you have future package installed: pip install --user future.

Command line options

Standalone run options

• -b <filename> — provide path to ELF binary file to execute.
• -n <number> — number of instructions to run. If omitted, simulation continues until halting system call or jump to null is executed.

ISA and system-level options:

• -I — modeled ISA. Default version is mars.
  • mips32, mips64 — state-of-the-art MIPS
  • riscv32, riscv64, riscv128 — RISC-V with all instructions
  • mars, mars64 — simplified MIPS without delayed branches
  • mipsI, mipsII, mipsIII, mipsIV — legacy MIPS versions
• -f — enables functional simulation only
• --mars — enables MARS-compatible mode of system calls
• -d — enables detailed output of each cycle

Performance mode options

Branch prediction

• --bp-mode — prediction mode. Check supported modes in manual.
• --bp-size — branch prediction cache size (amount of tracked branch instructions)
• --bp-ways — # of ways in branch prediction cache

Instruction cache

• --icache-size — instruction cache size in bytes
• --icache-ways — # of ways in instruction cache
• --icache-line-size — line size of instruction cache

Execution pipeline

• --long-alu-latency - number of execution stages required for long arithmetic instructions to be complete

Workflow example

Clone

1. Check that your environment meets all the requirements above.
2. Clone repository with submodules: git clone --recursive https://github.com/MIPT-ILab/mipt-mips.git

Build

To build simulator faster, we recommend to install Ninja.

1. Create a new build directory somewhere, then cd into it: mkdir /path/to/your/build/directory
2. Go to the build directory: cd /path/to/your/build/directory
3. Run cmake /path/to/mipt-mips/simulator -G "Ninja" to configure CMake
4. Run ninja to get the mipt-mips binary file
5. If you changed some source code files, just type ninja to rebuild project

Run

1. Now you can run simulation: ./mipt-mips -b /path/to/mips/binary
2. See more command line options in the paragraph below

Test

1. Go to mipt-tests subdirectory and build MIPS traces just by typing make
2. To run all unit tests, call ninja unit-tests && ctest --verbose -C Release from your build directory.

About MIPT-MIPS / MIPT-V

This project is a part of ILab activity at Moscow Institute of Physics and Technology (MIPT).

The main goal of the project is to teach the students the computer architecture through development of a microprocessor implementing the MIPS and RISC-V instruction set in both functional and performance simulators.

May I contribute?

Yes, if you attend MIPT-MIPS lectures. See our contributing.md file for details.