FEX-Emu--FEX/docs/SourceOutline.md

FEX-2405

FEXCore

See FEXCore/Readme.md for more details

Glossary

• Splatter: a code generator backend that concaternates configurable macros instead of doing isel
• IR: Intermediate Representation, our high-level opcode representation, loosely modeling arm64
• SSA: Single Static Assignment, a form of representing IR in memory
• Basic Block: A block of instructions with no control flow, terminated by control flow
• Fragment: A Collection of basic blocks, possibly an entire guest function or a subset of it

backend

IR to host code generation

arm64

• ALUOps.cpp
• Arm64Relocations.cpp: relocation logic of the arm64 splatter backend
• AtomicOps.cpp
• BranchOps.cpp
• ConversionOps.cpp
• EncryptionOps.cpp
• FlagOps.cpp
• JIT.cpp: Main glue logic of the arm64 splatter backend
• JITClass.h
• MemoryOps.cpp
• MiscOps.cpp
• MoveOps.cpp
• VectorOps.cpp

shared

• CPUBackend.h

frontend

x86-meta-blocks

• Frontend.cpp: Extracts instruction & block meta info, frontend multiblock logic

x86-tables

Metadata that drives the frontend x86/64 decoding

• BaseTables.cpp
• DDDTables.cpp
• EVEXTables.cpp
• H0F38Tables.cpp
• H0F3ATables.cpp
• PrimaryGroupTables.cpp
• SecondaryGroupTables.cpp
• SecondaryModRMTables.cpp
• SecondaryTables.cpp
• VEXTables.cpp
• X86Tables.h
• X87Tables.cpp
• XOPTables.cpp
• X86Tables.cpp

x86-to-ir

• Crypto.cpp: Handles x86/64 Crypto instructions to IR
• Flags.cpp: Handles x86/64 flag generation
• Vector.cpp: Handles x86/64 Vector instructions to IR
• X87.cpp: Handles x86/64 x87 to IR
• X87F64.cpp: Handles x86/64 x87 to IR
• OpcodeDispatcher.cpp: Handles x86/64 ops to IR, no-pf opt, local-flags opt

glue

Logic that binds various parts together

block-database

• LookupCache.cpp: Stores information about blocks, and provides C++ implementations to lookup the blocks

driver

Emulation mainloop related glue logic

• Core.cpp: Glues Frontend, OpDispatcher and IR Opts & Compilation, LookupCache, Dispatcher and provides the Execution loop entrypoint

log-manager

• LogManager.cpp

thunks

FEXCore side of thunks: Registration, Lookup

• Thunks.cpp
• Thunks.h

x86-guest-code

• X86HelperGen.cpp: Guest-side assembly helpers used by the backends
• X86HelperGen.h

ir

debug

• IRDumperPass.cpp: Prints IR

dumper

IR -> Text

• IRDumper.cpp

emitter

C++ Functions to generate IR. See IR.json for spec.

• IREmitter.cpp

opts

IR to IR Optimization

• PassManager.cpp: Defines which passes are run, and runs them
• PassManager.h
• ConstProp.cpp: ConstProp, ZExt elim, addressgen coalesce, const pooling, fcmp reduction, const inlining
• DeadCodeElimination.cpp
• DeadContextStoreElimination.cpp: Transforms ContextLoad/Store to temporaries, similar to mem2reg
• DeadStoreElimination.cpp: Cross block store-after-store elimination
• IRValidation.cpp: Sanity checking pass
• InlineCallOptimization.cpp: Removes unused arguments if known syscall number
• LongDivideRemovalPass.cpp: Long divide elimination pass
• RedundantFlagCalculationElimination.cpp: This is not used right now, possibly broken
• RegisterAllocationPass.cpp
• RegisterAllocationPass.h

opcodes

cpuid

• CPUID.cpp: Handles presented capability bits for guest cpu

dispatcher-implementations

• Crypto.cpp: Handles x86/64 Crypto instructions to IR
• Flags.cpp: Handles x86/64 flag generation
• Vector.cpp: Handles x86/64 Vector instructions to IR
• X87.cpp: Handles x86/64 x87 to IR
• X87F64.cpp: Handles x86/64 x87 to IR
• OpcodeDispatcher.cpp: Handles x86/64 ops to IR, no-pf opt, local-flags opt

ThunkLibs

See ThunkLibs/README.md for more details

thunklibs

These are generated + glue logic 1:1 thunks unless noted otherwise

EGL

• libEGL_Guest.cpp: Depends on glXGetProcAddress thunk
• libEGL_Host.cpp

GL

• libGL_Guest.cpp: Handles glXGetProcAddress
• libGL_Host.cpp: Uses glXGetProcAddress instead of dlsym

SDL2

• libSDL2_Guest.cpp: Handles sdlglproc, dload, stubs a few log fns
• libSDL2_Host.cpp

VDSO

• libVDSO_Guest.cpp: Linux VDSO thunking

Vulkan

• Guest.cpp
• Host.cpp

X11

• libXext_Guest.cpp
• libXext_Host.cpp
• libXfixes_Guest.cpp
• libXfixes_Host.cpp
• libXrender_Guest.cpp
• libXrender_Host.cpp

asound

• libasound_Guest.cpp
• libasound_Host.cpp

cef

• libcef_Guest.cpp
• libcef_Host.cpp

drm

• Guest.cpp
• Host.cpp

fex_malloc

• Guest.cpp: Handles allocations between guest and host thunks
• Host.cpp: Handles allocations between guest and host thunks

fex_malloc_loader

• Guest.cpp: Delays malloc symbol replacement until it is safe to run constructors

fex_malloc_symbols

• Host.cpp: Allows FEX to export allocation symbols

fex_thunk_test

• Guest.cpp
• Host.cpp

wayland-client

• Guest.cpp
• Host.cpp

xshmfence

• Guest.cpp
• Host.cpp

Source/Tests

unittests

See unittests/Readme.md for more details