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Ryan Houdek
c5754145c5
As said in the implementation of this struct commit message. This new pair struct optimizes specific cases of small forward only increments that can fit in to 8-bit space, and small forward or backward jump cases that fit in to 16-bit space. Some stats of this change: - Steam: 5.88MB down to 4.34MB. 73.8% the space consumed - Steamwebhelper: 15.8MB down to 13.24MB. 83.8% space consumed - Sonic Mania: 3.6MB down to 2.58MB. 71.6% space consumed As for absolute stats when compared to all code buffer size: - Steam: 86MB of code buffer to 5.88MB -> 4.34MB of RIP reconstruction. - 6.8% -> 5% code buffer space used for RIP reconstruction - Steamwebhelper: 285MB of code buffer to 17MB -> 14.26MB of RIP reconstruction. - 5.9% -> 4.9% code buffer space used for RIP reconstruction - Sonic Mania: 48.53MB of code buffer to 3.55MB -> 2.53MB of RIP reconstruction. - 7.3% -> 5.2% code buffer space used for RIP reconstruction
FEXCore - Fast x86 Core emulation library
This is the core emulation library that is used for the FEX emulator project. This project aims to provide a fast and functional x86-64 emulation library that can meet and surpass other x86-64 emulation libraries.
Goals
- Be as fast as possible, beating and exceeding current options for x86-64 emulation
- 25% - 50% lower performance than native code would be desired target
- Use an IR to efficiently translate x86-64 to our host architecture
- Support a tiered recompiler to allow for fast runtime performance
- Support offline compilation and offline tooling for inspection and performance analysis
- Support threaded emulation. Including emulating x86-64's strong memory model on weak memory model architectures
- Support a significant portion of the x86-64 instruction space.
- Including MMX, SSE, SSE2, SSE3, SSSE3, and SSE4*
- Support fallback routines for uncommonly used x86-64 instructions
- Including x87 and 3DNow!
- Only support userspace emulation.
- All x86-64 instructions run as if they are under CPL-3(userland) security layer
- Minimal Linux Syscall emulation for testing purposes
- Portable library implementation in order to support easy integration in to applications
Target Host Architecture
The target host architecture for this library is AArch64. Specifically the ARMv8.1 version or newer. The CPU IR is designed with AArch64 in mind but should allow for other architectures as well. x86-64 host support is available for ease of development, but is not a priority.
Not desired
- Kernel space emulation
- CPL0-2 emulation
- Real Mode, Protected Mode, Virtual-8086 Mode, System Management Mode
- IRQs
- SVM
- "Cycle Accurate" emulation