João Victor Amorim
3005babab8
Completes the fused-FMA slice deferred by the VOP3P first slice (#145). v_pk_fma_f16 previously failed emission loudly because an f32 multiply-add followed by an f16 pack rounds twice; the pinned miss is fma(0x4100, 0x7522, 0x04EA) = 0x7A6B fused vs 0x7A6A via f32. The f32 product of two f16 values is exact, so only the addition needs correcting: compute sum = RN(product + addend), recover the exact residual with Knuth 2Sum, and if the sum is inexact with an even significand, step one ulp towards the true value. That is round-to-odd, and rounding the f32 result to f16 with round-to-nearest-even then matches a true fused f16 FMA exactly (24 significand bits >= 11 + 2). Inf/NaN inputs turn the residual into NaN, the ordered compare skips the parity fix, and IEEE special behaviour passes through unchanged. The op_sel/op_sel_hi/neg_lo/neg_hi source modifiers apply to src2 through the existing operand path; clamp stays rejected like the other packed ops. Every op in the 2Sum chain is decorated NoContraction: without it the AMD RDNA3 Windows driver folds the sequence, collapses the residual to zero, and the midpoint case decays to the double-rounded result. This was caught by running the emitted shader on a real device (see below). Verification: - A mirror of the emitted sequence was checked against an exact integer reference (every finite f16 is m * 2^-24, so a*b + c is an exact Int128 multiple of 2^-48, rounded once to f16 RNE) across 34M cases: directed midpoint pins, random sweeps over all operand classes, tiny-addend midpoint stress, subnormal products, and Inf/NaN propagation. 0 mismatches. - ShaderDump gains a pk-f16 program covering all five packed opcodes, both fma modifier paths, and the pinned constants; all programs decode and emit. - The executable exec program now computes the pinned fma and its negated-addend twin (0x7A6B7A6B / 0x7A6A7A6A, straddling an f16 midpoint) and stores them at offsets 20/24; GpuConformance checks both on device. All values match on an AMD Radeon RX 7700 XT.
SharpEmu
An experimental PlayStation 5 emulator for Windows, Linux and macOS.
Join our Discord for development updates, compatibility discussions, support, and community chat.
Note
SharpEmu supports Windows x64, Linux x64, and macOS x64. Apple Silicon Macs can run the macOS x64 build through Rosetta 2, and Windows on ARM devices (e.g. Snapdragon) can run the Windows x64 build through Windows' built-in x64 emulation.
Warning
SharpEmu is an experimental PS5 emulator developed from scratch in C#. The current focus is on accuracy and infrastructure setup rather than game-specific compatibility.
Info
SharpEmu is an emulator project currently in its early stages of development.
This project is developed purely for research and educational purposes. There are no commercial goals associated with it. We enjoy learning about system architecture and reverse engineering.
SharpEmu focuses exclusively on the PlayStation 5.
Our goal is not to emulate PS4 games, as there is already an excellent emulator dedicated to that platform: ShadPS4.
Games Tested
| Demons Souls Remake | Dreaming Sarah |
|---|---|
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| Void Terrarium | Dead Cells |
|---|---|
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Status
The emulator can currently load the eboot.bin of real games, execute native CPU instructions, and partially handle kernel-related functionality. However, several critical components are still missing.
Current capabilities include:
- Loading
eboot.binand.elffiles - Executing native CPU instructions
- Reading basic game metadata (title, version, etc.)
- Loading system modules (
prx/sys_module) - Partial support for some kernel functions
FiberandAMPRexports- PlayGo scenarios
- Initial loading game files
- Shader/resource submits and AGC initial
- Video outputs in some games
Some games have reached like sceVideoOut and AGC stages.
SharpEmu supports Windows, Linux, and macOS hosts. Video output uses Vulkan on Windows and Linux, and MoltenVK on macOS. Platform support is still experimental, so compatibility and performance vary by game, operating system, and GPU driver.
Using
Download the release archive for your operating system, extract it, and launch
SharpEmu with the path to a legally obtained game's eboot.bin.
Windows PowerShell:
.\SharpEmu.exe "C:\path\to\game\eboot.bin" 2>&1 |
Tee-Object -FilePath "SharpEmu.log"
Linux and macOS:
chmod +x ./SharpEmu
./SharpEmu "/path/to/game/eboot.bin" 2>&1 |
tee SharpEmu.log
A Vulkan-capable GPU and current graphics driver are required. The macOS release includes the MoltenVK Vulkan implementation.
Important
This project does not support or condone piracy.
All games used during development and testing are dumped from consoles that we personally own.
Users are expected to use legally obtained copies of their games.
Build
- Install the .NET SDK version specified in
global.json. - Clone the repository:
git clone https://github.com/sharpemu/sharpemu.git - Open the solution file (
SharpEmu.slnx) in VSCode. - Build the project:
dotnet buildordotnet publish - Build artifacts will be located in the
artifactsdirectory.
Disclaimer
SharpEmu is an experimental emulator intended for research and educational purposes.
This project does not contain any copyrighted system firmware, game data, or proprietary PlayStation assets.
Special Thanks
The following projects were extremely helpful during development:
-
ShadPS4
Helped with understanding the basic architecture of the PlayStation 4. -
Kyty
One of the few PS5 emulator projects available and very useful for studying native code execution. -
Ryujinx
Provided valuable references for filesystem handling and low-level C# implementation patterns.
License
Contributing
Before opening an issue or pull request, please read our contribution guidelines:
The guide covers:
- Coding style and formatting
- AI-assisted contributions
- Pull request expectations
- Testing guidelines
- Legal and reverse engineering policy