The developers behind RPCS3, the popular PlayStation 3 emulator, have just announced a major "breakthrough" in emulating the PS3's Cell Broadband Engine processor, reportedly leading to optimisations across all games (h/t: Tom's Hardware).
Historically, the PS3's Cell processor has famously created a lot of headaches for developers hoping to accurately emulate the console, due to its unique architecture when compared to your run-of-the-mill PC hardware. For instance, it notably included a general-purpose PowerPC core with multiple specialised coprocessors, called Synergistic Processing Elements (SPEs), each of which contains a 128-bit SIMD SPU called a Synergistic Processing Unit (or SPU, for short).
It's these SPUs that have, in the past, regularly led to CPU bottlenecks, with the RPCS3 team having to recompile the original Cell instructions into native x86 code using LLVM and ASMJIT "backends" to execute on CPU host threads, rather than simultaneously, like on the PS3. This can lead to potential losses in game performance.
Taking to Twitter/X, recently, the RPCS3 account has revealed that its team member, Elad, has discovered "new SPU usage patterns," giving the group fresh ways to generate more optimized PC code. This has led to some significant gains in some "of the most SPU-intensive games," including Eat Sleep Play's 2012 reboot of Twisted Metal, which has seen "a 5-7% Average FPS improvement" between version v.0.0.40-19096 and v0.0.40-19151 of the emulator.
Reacting to this news, James Stanard, the principal engine developer for Twisted Metal, said, "I wrote 90% of the SPU code in Twisted Metal. (A lot of it was moving PostFX off the GPU.) I'm proud that it got called out for being SPU-intensive. It sure was! We basically maxed out the PPU, SPUs, and RSX all at the same time."
He congratulated the team on its efforts, calling it "amazing work," and admitted he "was convinced at the time [of developing the game] that the PS3 would never be emulatable!"
Elsewhere, the RPCS3 social media account revealed, "All CPUs can benefit from this, from low-end to high-end," before adding, "We have even received reports from a user running a dual-core Athlon 3000G CPU showing improved audio rendering and slightly better performance in Gran Turismo 5."