cadmic
99113e2da6
* Match frameSetSize * Match frameResetUCode and frameScaleMatrix * Match _frameDrawRectangle * Match frameGetDepth * Match frameConvertYUVtoRGB * Match packTakeBlocks * Match frameMakeTexture * Match frameLoadTile * Match frameCullDL * Match frameInvalidateCache and frameUpdateCache * Match frameLoadTexture * Move CopyCFB * Match frameSetViewport * Small fixes
oot-gc
This repo contains a WIP decompilation of the N64 Emulator ELF executable intended for use with the Gamecube releases of The Legend of Zelda Ocarina of Time. Currently the decompilation specifically targets the version shipped with the Japanese Zelda Collector's Edition disk as symbols and other debugging information was left unstripped.
It builds the following ELF executables:
SIM.elf : md5: 64428C7350B31E0AAD3DDE221C5B18A5
SIM_S.elf : md5: EDDD2DED9906AD2312F7EC585B3D72CE
SIM_S is a version of the build with stripped symbols which when diffed against a similarly stripped original matches byte for byte if assembled and linked, which is the most realistic goal for verifying the accuracy of the decompilation.
Building
Requirements
You will need the following dependencies:
- gcc or clang
- make
- git
- python3
- wibo (Linux) or wine (macOS)
- wget
- unzip
- clang-format (optional)
Ubuntu/Debian
In order to install wibo, you will need to download it and run:
sudo install wibo /usr/bin
You can install the dependencies with the following commands:
sudo apt-get update
sudo apt-get install build-essential git python3 wget unzip
macOS
You can install dependencies via Homebrew with the following command:
brew install coreutils python3 wget wine
Instructions
- Obtain the original ELF executable found in the
120903_zelda.tgcfile on the Japanese Collector's Edition disk and place it in the base working directory and name itSIM_original.elf - Run
make setupandmake
Development
First, copy a matching build to the expected/ directory to diff against:
mkdir expected
cp -r build expected/
Diff tools
For locally diffing the current build against the expected build:
objdiff: Start the objdiff GUI and open this directory as the project directory.diff.py(asm-differ): Run e.g../diff.py -mwo3 xlMainto diff a function.vbindiff: Runvbindiff SIM_S.elf build/SIM/SIM_S.elfto directly diff the ELF files to debug tricky matching issues, using the ELF section headers and the linker map file to locate the diffs in the code.
decomp.me
Run tools/decompme.py <c-file> <asm-file> (e.g. tools/decompme.py src/emulator/cpu.c asm/non_matchings/cpu/cpuExecute.s) to create a
decomp.me scratch for a function. The C file and all of its included headers will be used as the context.
Permuter
To import a function for decomp-permuter, ensure powerpc-eabi-objdump binary
is on your PATH (for instance by adding tools/binutils from this project) and run something like
path/to/permuter/import.py src/emulator/THPRead.c asm/non_matchings/THPRead/Reader.s
path/to/permuter/permuter.py nonmatchings/Reader -j 8
Sometimes you may need to tweak the source in order for things to import
correctly, for example by explicitly marking auto-inlined functions as inline.
Debug Info
The files in the debug/ directory contain a dump of the DWARF debugging information in the original ELF. Functions marked as // Erased
were present at one time but have been stripped by the linker, because they were either unused or inlined at all call sites.
Migrating a file to C
All emulator files have been migrated to C, but some SDK and standard library files are still built from the disassembly. Before decompiling one of these files:
- In
obj_files.mk, replace$(BUILD_DIR)/asm/<path>.owith$(BUILD_DIR)/src/<path>.oto link the new object file - Add an entry in
objdiff.json - Run
cp expected/build/SIM/asm/<path>.o expected/build/SIM/src/<path>.oto create a base to diff against