freedom-u-sdk VS Unicorn Engine

They are based on HiFive Unleashed OpenOCD configuration file on old Freedom U SDK but heavily modified for the latest version of RISC-V OpenOCD (and to enable debugging on U74 cores).

For this experiment distro that I ran benchmark on, I use the new 2021.05.00 image and replaced rootfs with my own. I guess as long as FSBL from fusdk 2021.05 is used, then the Unmatched will run at 1.2 GHz.

OFRAK Tetris is a project I started at work about two weeks ago. It's a web-based game that works on desktop and mobile. I made it for my company to bring to events like DEF CON, and to promote our binary analysis and patching framework called OFRAK.

In the game, 32-bit, little-endian ARM assembly instructions fall, and you can modify the operands before executing them on a CPU emulator. There are two segments mapped – one for instructions, and one for data (though both have read, write, and execute permissions). Your score is a four byte signed integer stored at the virtual address pointed to by the R12 register, and the goal is to use the instructions that fall to make the score value in memory as high as possible. When it's game over, you can download your game as an ELF to relive the glory in GDB on your favorite ARM device.

The CPU emulator is a version of Unicorn (https://www.unicorn-engine.org/) that has been cross-compiled to WebAssembly (https://alexaltea.github.io/unicorn.js/), so everything on the page runs in the browser without the need for any complicated infrastructure on the back end.

Since I've only been working on this for a short period of time leading up to its debut at DEF CON, there are still many more features I'd eventually like to implement. These include adding support for other ISAs besides ARM, adding an instruction reference manual, and lots of little cleanups, bug fixes, and adjustments.

My highest score is 509,644,979, but my average is about 131,378.

I look forward to feedback, bug reports, feature requests, and strategy discussions!

Entails hundreds of hours of single-stepping through that opcode in Linux kernel using an indirect operand pointing toward its own opcode (self-modifying code).

Even the extraordinaire Fabrice Bellard (author of QEMU) admitted that it is broke and did a total rewrite, which fixed tons of other issues.

https://github.com/unicorn-engine/unicorn/issues/364

Macdu (Vita3K dev) also stated that this game is CPU bound so they used a CPU emulator known as unicorn2 , this is also the reason for the slow speed

This is how I found out a snippet of assembly code that can actually distinguished between a KVM hypervisor and most of today’s emulator.

https://github.com/unicorn-engine/unicorn/issues/364