qt: Fix game name format error

Silence miscellaneous warnings

.ci/scripts/linux/docker.sh

@@ -5,10 +5,11 @@ cd /yuzu
 ccache -s
 
 mkdir build || true && cd build
-cmake .. -G Ninja -DYUZU_USE_BUNDLED_UNICORN=ON -DYUZU_USE_QT_WEB_ENGINE=ON -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/lib/ccache/gcc -DCMAKE_CXX_COMPILER=/usr/lib/ccache/g++ -DYUZU_ENABLE_COMPATIBILITY_REPORTING=${ENABLE_COMPATIBILITY_REPORTING:-"OFF"} -DENABLE_COMPATIBILITY_LIST_DOWNLOAD=ON -DUSE_DISCORD_PRESENCE=ON
+cmake .. -G Ninja -DDISPLAY_VERSION=$1 -DYUZU_USE_BUNDLED_UNICORN=ON -DYUZU_USE_QT_WEB_ENGINE=ON -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/lib/ccache/gcc -DCMAKE_CXX_COMPILER=/usr/lib/ccache/g++ -DYUZU_ENABLE_COMPATIBILITY_REPORTING=${ENABLE_COMPATIBILITY_REPORTING:-"OFF"} -DENABLE_COMPATIBILITY_LIST_DOWNLOAD=ON -DUSE_DISCORD_PRESENCE=ON
 
 ninja
 
 ccache -s
 
-ctest -VV -C Release
+# Ignore zlib's tests, since they aren't gated behind a CMake option.
+ctest -VV -E "(example|example64)" -C Release

.ci/scripts/linux/exec.sh

@@ -2,4 +2,4 @@
 
 mkdir -p "ccache"  || true
 chmod a+x ./.ci/scripts/linux/docker.sh
-docker run -e ENABLE_COMPATIBILITY_REPORTING -e CCACHE_DIR=/yuzu/ccache -v $(pwd):/yuzu yuzuemu/build-environments:linux-fresh /bin/bash /yuzu/.ci/scripts/linux/docker.sh
+docker run -e ENABLE_COMPATIBILITY_REPORTING -e CCACHE_DIR=/yuzu/ccache -v $(pwd):/yuzu yuzuemu/build-environments:linux-fresh /bin/bash /yuzu/.ci/scripts/linux/docker.sh $1

.ci/scripts/windows/docker.sh

@@ -13,7 +13,7 @@ echo '' >> /bin/cmd
 chmod +x /bin/cmd
 
 mkdir build || true && cd build
-cmake .. -G Ninja -DCMAKE_TOOLCHAIN_FILE="$(pwd)/../CMakeModules/MinGWCross.cmake" -DUSE_CCACHE=ON -DYUZU_USE_BUNDLED_UNICORN=ON -DENABLE_COMPATIBILITY_LIST_DOWNLOAD=ON -DCMAKE_BUILD_TYPE=Release
+cmake .. -G Ninja -DDISPLAY_VERSION=$1 -DCMAKE_TOOLCHAIN_FILE="$(pwd)/../CMakeModules/MinGWCross.cmake" -DUSE_CCACHE=ON -DYUZU_USE_BUNDLED_UNICORN=ON -DENABLE_COMPATIBILITY_LIST_DOWNLOAD=ON -DCMAKE_BUILD_TYPE=Release
 ninja
 
 # Clean up the dirty hacks

.ci/scripts/windows/exec.sh

@@ -2,4 +2,4 @@
 
 mkdir -p "ccache" || true
 chmod a+x ./.ci/scripts/windows/docker.sh
-docker run -e CCACHE_DIR=/yuzu/ccache -v $(pwd):/yuzu yuzuemu/build-environments:linux-mingw /bin/bash -ex /yuzu/.ci/scripts/windows/docker.sh
+docker run -e CCACHE_DIR=/yuzu/ccache -v $(pwd):/yuzu yuzuemu/build-environments:linux-mingw /bin/bash -ex /yuzu/.ci/scripts/windows/docker.sh $1

.ci/scripts/windows/upload.ps1

@@ -0,0 +1,32 @@
+$GITDATE = $(git show -s --date=short --format='%ad') -replace "-",""
+$GITREV = $(git show -s --format='%h')
+$RELEASE_DIST = "yuzu-windows-msvc"
+
+$MSVC_BUILD_ZIP = "yuzu-windows-msvc-$GITDATE-$GITREV.zip" -replace " ", ""
+$MSVC_BUILD_PDB = "yuzu-windows-msvc-$GITDATE-$GITREV-debugsymbols.zip" -replace " ", ""
+$MSVC_SEVENZIP = "yuzu-windows-msvc-$GITDATE-$GITREV.7z" -replace " ", ""
+
+$env:BUILD_ZIP = $MSVC_BUILD_ZIP
+$env:BUILD_SYMBOLS = $MSVC_BUILD_PDB
+$env:BUILD_UPDATE = $MSVC_SEVENZIP
+
+$BUILD_DIR = ".\build\bin\Release"
+
+mkdir pdb
+Get-ChildItem "$BUILD_DIR\" -Recurse -Filter "*.pdb" | Copy-Item -destination .\pdb
+7z a -tzip $MSVC_BUILD_PDB .\pdb\*.pdb
+rm "$BUILD_DIR\*.pdb"
+mkdir $RELEASE_DIST
+mkdir "artifacts"
+
+Copy-Item "$BUILD_DIR\*" -Destination $RELEASE_DIST -Recurse
+rm "$RELEASE_DIST\*.exe"
+Get-ChildItem "$BUILD_DIR" -Recurse -Filter "yuzu*.exe" | Copy-Item -destination $RELEASE_DIST
+Get-ChildItem "$BUILD_DIR" -Recurse -Filter "QtWebEngineProcess*.exe" | Copy-Item -destination $RELEASE_DIST
+Copy-Item .\license.txt -Destination $RELEASE_DIST
+Copy-Item .\README.md -Destination $RELEASE_DIST
+7z a -tzip $MSVC_BUILD_ZIP $RELEASE_DIST\*
+7z a $MSVC_SEVENZIP $RELEASE_DIST
+
+Get-ChildItem . -Filter "*.zip" | Copy-Item -destination "artifacts"
+Get-ChildItem . -Filter "*.7z" | Copy-Item -destination "artifacts"

.ci/templates/build-msvc.yml

@@ -0,0 +1,22 @@
+parameters:
+  artifactSource: 'true'
+  cache: 'false'
+  version: ''
+
+steps:
+- script: mkdir build && cd build && cmake -G "Visual Studio 15 2017 Win64" --config Release -DYUZU_USE_BUNDLED_QT=1 -DYUZU_USE_BUNDLED_SDL2=1 -DYUZU_USE_BUNDLED_UNICORN=1 -DYUZU_USE_QT_WEB_ENGINE=ON -DENABLE_COMPATIBILITY_LIST_DOWNLOAD=ON -DYUZU_ENABLE_COMPATIBILITY_REPORTING=${COMPAT} -DUSE_DISCORD_PRESENCE=ON -DDISPLAY_VERSION=${{ parameters['version'] }} .. && cd ..
+  displayName: 'Configure CMake'
+- task: MSBuild@1
+  displayName: 'Build'
+  inputs:
+    solution: 'build/yuzu.sln'
+    maximumCpuCount: true
+    configuration: release
+- task: PowerShell@2
+  displayName: 'Package Artifacts'
+  inputs:
+    targetType: 'filePath'
+    filePath: './.ci/scripts/windows/upload.ps1'
+- publish: artifacts
+  artifact: 'yuzu-$(BuildName)-windows-msvc'
+  displayName: 'Upload Artifacts'

.ci/templates/build-single.yml

@@ -1,10 +1,9 @@
 parameters:
   artifactSource: 'true'
   cache: 'false'
+  version: ''
 
 steps:
-- script: export DATE=`date '+%Y.%m.%d'` && export CI=true && AZURE_REPO_NAME=yuzu-emu/yuzu-$(BuildName) && AZURE_REPO_TAG=$(BuildName)-$DATE
-  displayName: 'Determine Build Name'
 - task: DockerInstaller@0
   displayName: 'Prepare Environment'
   inputs:
@@ -15,7 +14,7 @@ steps:
     key: yuzu-v1-$(BuildName)-$(BuildSuffix)-$(CacheSuffix)
     path: $(System.DefaultWorkingDirectory)/ccache
     cacheHitVar: CACHE_RESTORED
-- script: chmod a+x ./.ci/scripts/$(ScriptFolder)/exec.sh && ./.ci/scripts/$(ScriptFolder)/exec.sh
+- script: chmod a+x ./.ci/scripts/$(ScriptFolder)/exec.sh && ./.ci/scripts/$(ScriptFolder)/exec.sh ${{ parameters['version'] }}
   displayName: 'Build'
 - script: chmod a+x ./.ci/scripts/$(ScriptFolder)/upload.sh && RELEASE_NAME=$(BuildName) ./.ci/scripts/$(ScriptFolder)/upload.sh
   displayName: 'Package Artifacts'

.ci/templates/build-standard.yml

@@ -1,3 +1,6 @@
+parameters:
+  version: ''
+
 jobs:
 - job: build
   displayName: 'standard'
@@ -20,4 +23,5 @@ jobs:
   - template: ./build-single.yml
     parameters:
       artifactSource: 'false'
-      cache: $(parameters.cache)
+      cache: $(parameters.cache)
+      version: $(parameters.version)

.ci/templates/build-testing.yml

@@ -1,3 +1,6 @@
+parameters:
+  version: ''
+
 jobs:
 - job: build_test
   displayName: 'testing'
@@ -31,3 +34,4 @@ jobs:
       parameters:
         artifactSource: 'false'
         cache: 'false'
+        version: $(parameters.version)

.ci/templates/mergebot.yml

@@ -11,5 +11,5 @@ steps:
     inputs:
       scriptSource: 'filePath'
       scriptPath: '.ci/scripts/merge/apply-patches-by-label.py'
-      arguments: '${{ parameters.matchLabel }} patches'
+      arguments: '${{ parameters.matchLabel }} Tagged patches'
       workingDirectory: '$(System.DefaultWorkingDirectory)'

.ci/templates/release-download.yml

@@ -2,7 +2,7 @@ steps:
   - task: DownloadPipelineArtifact@2
     displayName: 'Download Windows Release'
     inputs:
-      artifactName: 'yuzu-$(BuildName)-windows-mingw'
+      artifactName: 'yuzu-$(BuildName)-windows-msvc'
       buildType: 'current'
       targetPath: '$(Build.ArtifactStagingDirectory)'
   - task: DownloadPipelineArtifact@2

.ci/yuzu-mainline-step2.yml

@@ -1,6 +1,9 @@
 trigger:
 - master
 
+variables:
+  DisplayVersion: $[counter(variables['DisplayPrefix'], 1)]
+
 stages:
 - stage: format
   displayName: 'format'
@@ -15,12 +18,49 @@ stages:
   dependsOn: format
   displayName: 'build'
   jobs:
-  - template: ./templates/build-standard.yml
-    parameters:
-      cache: 'true'
+  - job: build
+    displayName: 'standard'
+    pool:
+      vmImage: ubuntu-latest
+    strategy:
+      maxParallel: 10
+      matrix:
+        linux:
+          BuildSuffix: 'linux'
+          ScriptFolder: 'linux'
+    steps:
+    - template: ./templates/sync-source.yml
+      parameters:
+        artifactSource: $(parameters.artifactSource)
+        needSubmodules: 'true'
+    - template: ./templates/build-single.yml
+      parameters:
+        artifactSource: 'false'
+        cache: 'true'
+        version: $(DisplayVersion)
+- stage: build_win
+  dependsOn: format
+  displayName: 'build-windows'
+  jobs:
+  - job: build
+    displayName: 'msvc'
+    pool:
+      vmImage: vs2017-win2016
+    steps:
+    - template: ./templates/sync-source.yml
+      parameters:
+        artifactSource: $(parameters.artifactSource)
+        needSubmodules: 'true'
+    - template: ./templates/build-msvc.yml
+      parameters:
+        artifactSource: 'false'
+        cache: 'true'
+        version: $(DisplayVersion)
 - stage: release
   displayName: 'Release'
-  dependsOn: build
+  dependsOn:
+  - build
+  - build_win
   jobs:
   - job: github
     displayName: 'GitHub Release'

.ci/yuzu-patreon-step2.yml

@@ -1,6 +1,9 @@
 trigger:
 - master
 
+variables:
+  DisplayVersion: $[counter(variables['DisplayPrefix'], 1)]
+
 stages:
 - stage: format
   displayName: 'format'
@@ -15,14 +18,17 @@ stages:
   dependsOn: format
   displayName: 'build'
   jobs:
-  - template: ./templates/build-standard.yml
-    parameters:
-      cache: 'true'
-- stage: release
-  displayName: 'release'
-  dependsOn: build
-  jobs:
-  - job: azure
-    displayName: 'azure'
+  - job: build
+    displayName: 'windows-msvc'
+    pool:
+      vmImage: vs2017-win2016
     steps:
-    - template: ./templates/release-universal.yml
+    - template: ./templates/sync-source.yml
+      parameters:
+        artifactSource: $(parameters.artifactSource)
+        needSubmodules: 'true'
+    - template: ./templates/build-msvc.yml
+      parameters:
+        artifactSource: 'false'
+        cache: $(parameters.cache)
+        version: $(DisplayVersion)

.gitmodules

@@ -46,3 +46,9 @@
 [submodule "sirit"]
     path = externals/sirit
     url = https://github.com/ReinUsesLisp/sirit
+[submodule "libzip"]
+    path = externals/libzip
+    url = https://github.com/DarkLordZach/libzip
+[submodule "zlib"]
+    path = externals/zlib
+    url = https://github.com/madler/zlib

CMakeLists.txt

@@ -21,6 +21,8 @@ option(YUZU_USE_BUNDLED_UNICORN "Build/Download bundled Unicorn" ON)
 
 option(YUZU_USE_QT_WEB_ENGINE "Use QtWebEngine for web applet implementation" OFF)
 
+option(YUZU_ENABLE_BOXCAT "Enable the Boxcat service, a yuzu high-level implementation of BCAT" ON)
+
 option(ENABLE_CUBEB "Enables the cubeb audio backend" ON)
 
 option(ENABLE_VULKAN "Enables Vulkan backend" ON)

CMakeModules/GenerateSCMRev.cmake

@@ -83,9 +83,15 @@ set(HASH_FILES
     "${VIDEO_CORE}/shader/decode/video.cpp"
     "${VIDEO_CORE}/shader/decode/warp.cpp"
     "${VIDEO_CORE}/shader/decode/xmad.cpp"
+    "${VIDEO_CORE}/shader/ast.cpp"
+    "${VIDEO_CORE}/shader/ast.h"
     "${VIDEO_CORE}/shader/control_flow.cpp"
     "${VIDEO_CORE}/shader/control_flow.h"
+    "${VIDEO_CORE}/shader/compiler_settings.cpp"
+    "${VIDEO_CORE}/shader/compiler_settings.h"
     "${VIDEO_CORE}/shader/decode.cpp"
+    "${VIDEO_CORE}/shader/expr.cpp"
+    "${VIDEO_CORE}/shader/expr.h"
     "${VIDEO_CORE}/shader/node.h"
     "${VIDEO_CORE}/shader/node_helper.cpp"
     "${VIDEO_CORE}/shader/node_helper.h"

externals/CMakeLists.txt

@@ -77,6 +77,12 @@ if (ENABLE_VULKAN)
     add_subdirectory(sirit)
 endif()
 
+# zlib
+add_subdirectory(zlib EXCLUDE_FROM_ALL)
+
+# libzip
+add_subdirectory(libzip EXCLUDE_FROM_ALL)
+
 if (ENABLE_WEB_SERVICE)
     # LibreSSL
     set(LIBRESSL_SKIP_INSTALL ON CACHE BOOL "")

license.txt

@@ -341,15 +341,24 @@ Public License instead of this License.
 
 The icons used in this project have the following licenses:
 
-Icon Name                          | License       | Origin/Author
----                                | ---           | ---
-checked.png                        | Free for non-commercial use
-failed.png                         | Free for non-commercial use
-lock.png                           | CC BY-ND 3.0  | https://icons8.com
-plus_folder.png                    | CC BY-ND 3.0  | https://icons8.com
-bad_folder.png                     | CC BY-ND 3.0  | https://icons8.com
-chip.png                           | CC BY-ND 3.0  | https://icons8.com
-folder.png                         | CC BY-ND 3.0  | https://icons8.com
-plus.png (Default, Dark)           | CC0 1.0       | Designed by BreadFish64 from the Citra team
-plus.png (Colorful, Colorful Dark) | CC BY-ND 3.0  | https://icons8.com
-sd_card.png | CC BY-ND 3.0 | https://icons8.com
+Icon Name                                   | License       | Origin/Author
+---                                         | ---           | ---
+checked.png                                 | Free for non-commercial use
+failed.png                                  | Free for non-commercial use
+lock.png                                    | CC BY-ND 3.0  | https://icons8.com
+plus_folder.png (Default, Dark)             | CC BY-ND 3.0  | https://icons8.com
+bad_folder.png (Default, Dark)              | CC BY-ND 3.0  | https://icons8.com
+chip.png (Default, Dark)                    | CC BY-ND 3.0  | https://icons8.com
+folder.png (Default, Dark)                  | CC BY-ND 3.0  | https://icons8.com
+plus.png (Default, Dark)                    | CC0 1.0       | Designed by BreadFish64 from the Citra team
+sd_card.png (Default, Dark)                 | CC BY-ND 3.0  | https://icons8.com
+plus_folder.png (Colorful, Colorful Dark)   | CC BY-ND 3.0  | https://icons8.com
+bad_folder.png (Colorful, Colorful Dark)    | CC BY-ND 3.0  | https://icons8.com
+chip.png (Colorful, Colorful Dark)          | CC BY-ND 3.0  | https://icons8.com
+folder.png (Colorful, Colorful Dark)        | CC BY-ND 3.0  | https://icons8.com
+plus.png (Colorful, Colorful Dark)          | CC BY-ND 3.0  | https://icons8.com
+sd_card.png (Colorful, Colorful Dark)       | CC BY-ND 3.0  | https://icons8.com
+
+Note:
+Some icons are different in different themes, and they are separately listed
+only when they have different licenses/origins.

src/common/CMakeLists.txt

@@ -15,11 +15,23 @@ if (DEFINED ENV{CI})
     set(BUILD_TAG $ENV{AZURE_REPO_TAG})
   endif()
 endif()
+if (DEFINED ENV{TITLEBARFORMATIDLE})
+  set(TITLE_BAR_FORMAT_IDLE $ENV{TITLEBARFORMATIDLE})
+endif ()
+if (DEFINED ENV{TITLEBARFORMATRUNNING})
+  set(TITLE_BAR_FORMAT_RUNNING $ENV{TITLEBARFORMATRUNNING})
+endif ()
+if (DEFINED ENV{DISPLAYVERSION})
+  set(DISPLAY_VERSION $ENV{DISPLAYVERSION})
+endif ()
 add_custom_command(OUTPUT scm_rev.cpp
     COMMAND ${CMAKE_COMMAND}
       -DSRC_DIR="${CMAKE_SOURCE_DIR}"
       -DBUILD_REPOSITORY="${BUILD_REPOSITORY}"
+      -DTITLE_BAR_FORMAT_IDLE="${TITLE_BAR_FORMAT_IDLE}"
+      -DTITLE_BAR_FORMAT_RUNNING="${TITLE_BAR_FORMAT_RUNNING}"
       -DBUILD_TAG="${BUILD_TAG}"
+      -DBUILD_ID="${DISPLAY_VERSION}"
       -P "${CMAKE_SOURCE_DIR}/CMakeModules/GenerateSCMRev.cmake"
     DEPENDS
       # WARNING! It was too much work to try and make a common location for this list,
@@ -60,9 +72,15 @@ add_custom_command(OUTPUT scm_rev.cpp
       "${VIDEO_CORE}/shader/decode/video.cpp"
       "${VIDEO_CORE}/shader/decode/warp.cpp"
       "${VIDEO_CORE}/shader/decode/xmad.cpp"
+      "${VIDEO_CORE}/shader/ast.cpp"
+      "${VIDEO_CORE}/shader/ast.h"
       "${VIDEO_CORE}/shader/control_flow.cpp"
       "${VIDEO_CORE}/shader/control_flow.h"
+      "${VIDEO_CORE}/shader/compiler_settings.cpp"
+      "${VIDEO_CORE}/shader/compiler_settings.h"
       "${VIDEO_CORE}/shader/decode.cpp"
+      "${VIDEO_CORE}/shader/expr.cpp"
+      "${VIDEO_CORE}/shader/expr.h"
       "${VIDEO_CORE}/shader/node.h"
       "${VIDEO_CORE}/shader/node_helper.cpp"
       "${VIDEO_CORE}/shader/node_helper.h"

src/common/file_util.cpp

@@ -713,7 +713,6 @@ const std::string& GetUserPath(UserPath path, const std::string& new_path) {
         case UserPath::RootDir:
             user_path = paths[UserPath::RootDir] + DIR_SEP;
             break;
-
         case UserPath::UserDir:
             user_path = paths[UserPath::RootDir] + DIR_SEP;
             paths[UserPath::ConfigDir] = user_path + CONFIG_DIR DIR_SEP;
@@ -721,6 +720,8 @@ const std::string& GetUserPath(UserPath path, const std::string& new_path) {
             paths[UserPath::SDMCDir] = user_path + SDMC_DIR DIR_SEP;
             paths[UserPath::NANDDir] = user_path + NAND_DIR DIR_SEP;
             break;
+        default:
+            break;
         }
     }
 

src/common/scm_rev.cpp.in

@@ -11,6 +11,9 @@
 #define BUILD_DATE   "@BUILD_DATE@"
 #define BUILD_FULLNAME "@BUILD_FULLNAME@"
 #define BUILD_VERSION "@BUILD_VERSION@"
+#define BUILD_ID "@BUILD_ID@"
+#define TITLE_BAR_FORMAT_IDLE "@TITLE_BAR_FORMAT_IDLE@"
+#define TITLE_BAR_FORMAT_RUNNING "@TITLE_BAR_FORMAT_RUNNING@"
 #define SHADER_CACHE_VERSION "@SHADER_CACHE_VERSION@"
 
 namespace Common {
@@ -22,6 +25,9 @@ const char g_build_name[]   = BUILD_NAME;
 const char g_build_date[]   = BUILD_DATE;
 const char g_build_fullname[] = BUILD_FULLNAME;
 const char g_build_version[]  = BUILD_VERSION;
+const char g_build_id[] = BUILD_ID;
+const char g_title_bar_format_idle[] = TITLE_BAR_FORMAT_IDLE;
+const char g_title_bar_format_running[] = TITLE_BAR_FORMAT_RUNNING;
 const char g_shader_cache_version[] = SHADER_CACHE_VERSION;
 
 } // namespace

src/common/scm_rev.h

@@ -13,6 +13,9 @@ extern const char g_build_name[];
 extern const char g_build_date[];
 extern const char g_build_fullname[];
 extern const char g_build_version[];
+extern const char g_build_id[];
+extern const char g_title_bar_format_idle[];
+extern const char g_title_bar_format_running[];
 extern const char g_shader_cache_version[];
 
 } // namespace Common

src/core/CMakeLists.txt

@@ -1,3 +1,9 @@
+if (YUZU_ENABLE_BOXCAT)
+    set(BCAT_BOXCAT_ADDITIONAL_SOURCES hle/service/bcat/backend/boxcat.cpp hle/service/bcat/backend/boxcat.h)
+else()
+    set(BCAT_BOXCAT_ADDITIONAL_SOURCES)
+endif()
+
 add_library(core STATIC
     arm/arm_interface.h
     arm/arm_interface.cpp
@@ -82,6 +88,8 @@ add_library(core STATIC
     file_sys/vfs_concat.h
     file_sys/vfs_layered.cpp
     file_sys/vfs_layered.h
+    file_sys/vfs_libzip.cpp
+    file_sys/vfs_libzip.h
     file_sys/vfs_offset.cpp
     file_sys/vfs_offset.h
     file_sys/vfs_real.cpp
@@ -241,6 +249,9 @@ add_library(core STATIC
     hle/service/audio/errors.h
     hle/service/audio/hwopus.cpp
     hle/service/audio/hwopus.h
+    hle/service/bcat/backend/backend.cpp
+    hle/service/bcat/backend/backend.h
+    ${BCAT_BOXCAT_ADDITIONAL_SOURCES}
     hle/service/bcat/bcat.cpp
     hle/service/bcat/bcat.h
     hle/service/bcat/module.cpp
@@ -499,6 +510,15 @@ create_target_directory_groups(core)
 
 target_link_libraries(core PUBLIC common PRIVATE audio_core video_core)
 target_link_libraries(core PUBLIC Boost::boost PRIVATE fmt json-headers mbedtls opus unicorn open_source_archives)
+
+if (YUZU_ENABLE_BOXCAT)
+    get_directory_property(OPENSSL_LIBS
+        DIRECTORY ${PROJECT_SOURCE_DIR}/externals/libressl
+        DEFINITION OPENSSL_LIBS)
+    target_compile_definitions(core PRIVATE -DCPPHTTPLIB_OPENSSL_SUPPORT -DYUZU_ENABLE_BOXCAT)
+    target_link_libraries(core PRIVATE httplib json-headers ${OPENSSL_LIBS} zip)
+endif()
+
 if (ENABLE_WEB_SERVICE)
     target_compile_definitions(core PRIVATE -DENABLE_WEB_SERVICE)
     target_link_libraries(core PRIVATE web_service)

src/core/core.cpp

@@ -339,6 +339,7 @@ struct System::Impl {
 
     std::unique_ptr<Memory::CheatEngine> cheat_engine;
     std::unique_ptr<Tools::Freezer> memory_freezer;
+    std::array<u8, 0x20> build_id{};
 
     /// Frontend applets
     Service::AM::Applets::AppletManager applet_manager;
@@ -640,6 +641,14 @@ bool System::GetExitLock() const {
     return impl->exit_lock;
 }
 
+void System::SetCurrentProcessBuildID(std::array<u8, 32> id) {
+    impl->build_id = id;
+}
+
+const std::array<u8, 32>& System::GetCurrentProcessBuildID() const {
+    return impl->build_id;
+}
+
 System::ResultStatus System::Init(Frontend::EmuWindow& emu_window) {
     return impl->Init(*this, emu_window);
 }

src/core/core.h

@@ -330,6 +330,10 @@ public:
 
     bool GetExitLock() const;
 
+    void SetCurrentProcessBuildID(std::array<u8, 0x20> id);
+
+    const std::array<u8, 0x20>& GetCurrentProcessBuildID() const;
+
 private:
     System();
 

src/core/file_sys/bis_factory.cpp

@@ -136,4 +136,9 @@ u64 BISFactory::GetFullNANDTotalSpace() const {
     return static_cast<u64>(Settings::values.nand_total_size);
 }
 
+VirtualDir BISFactory::GetBCATDirectory(u64 title_id) const {
+    return GetOrCreateDirectoryRelative(nand_root,
+                                        fmt::format("/system/save/bcat/{:016X}", title_id));
+}
+
 } // namespace FileSys

src/core/file_sys/bis_factory.h

@@ -61,6 +61,8 @@ public:
     u64 GetUserNANDTotalSpace() const;
     u64 GetFullNANDTotalSpace() const;
 
+    VirtualDir GetBCATDirectory(u64 title_id) const;
+
 private:
     VirtualDir nand_root;
     VirtualDir load_root;

src/core/file_sys/vfs_libzip.cpp

@@ -0,0 +1,79 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <string>
+#include <zip.h>
+#include "common/logging/backend.h"
+#include "core/file_sys/vfs.h"
+#include "core/file_sys/vfs_libzip.h"
+#include "core/file_sys/vfs_vector.h"
+
+namespace FileSys {
+
+VirtualDir ExtractZIP(VirtualFile file) {
+    zip_error_t error{};
+
+    const auto data = file->ReadAllBytes();
+    std::unique_ptr<zip_source_t, decltype(&zip_source_close)> src{
+        zip_source_buffer_create(data.data(), data.size(), 0, &error), zip_source_close};
+    if (src == nullptr)
+        return nullptr;
+
+    std::unique_ptr<zip_t, decltype(&zip_close)> zip{zip_open_from_source(src.get(), 0, &error),
+                                                     zip_close};
+    if (zip == nullptr)
+        return nullptr;
+
+    std::shared_ptr<VectorVfsDirectory> out = std::make_shared<VectorVfsDirectory>();
+
+    const auto num_entries = zip_get_num_entries(zip.get(), 0);
+
+    zip_stat_t stat{};
+    zip_stat_init(&stat);
+
+    for (std::size_t i = 0; i < num_entries; ++i) {
+        const auto stat_res = zip_stat_index(zip.get(), i, 0, &stat);
+        if (stat_res == -1)
+            return nullptr;
+
+        const std::string name(stat.name);
+        if (name.empty())
+            continue;
+
+        if (name.back() != '/') {
+            std::unique_ptr<zip_file_t, decltype(&zip_fclose)> file{
+                zip_fopen_index(zip.get(), i, 0), zip_fclose};
+
+            std::vector<u8> buf(stat.size);
+            if (zip_fread(file.get(), buf.data(), buf.size()) != buf.size())
+                return nullptr;
+
+            const auto parts = FileUtil::SplitPathComponents(stat.name);
+            const auto new_file = std::make_shared<VectorVfsFile>(buf, parts.back());
+
+            std::shared_ptr<VectorVfsDirectory> dtrv = out;
+            for (std::size_t j = 0; j < parts.size() - 1; ++j) {
+                if (dtrv == nullptr)
+                    return nullptr;
+                const auto subdir = dtrv->GetSubdirectory(parts[j]);
+                if (subdir == nullptr) {
+                    const auto temp = std::make_shared<VectorVfsDirectory>(
+                        std::vector<VirtualFile>{}, std::vector<VirtualDir>{}, parts[j]);
+                    dtrv->AddDirectory(temp);
+                    dtrv = temp;
+                } else {
+                    dtrv = std::dynamic_pointer_cast<VectorVfsDirectory>(subdir);
+                }
+            }
+
+            if (dtrv == nullptr)
+                return nullptr;
+            dtrv->AddFile(new_file);
+        }
+    }
+
+    return out;
+}
+
+} // namespace FileSys

src/core/file_sys/vfs_libzip.h

@@ -0,0 +1,13 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "core/file_sys/vfs_types.h"
+
+namespace FileSys {
+
+VirtualDir ExtractZIP(VirtualFile zip);
+
+} // namespace FileSys

src/core/hle/service/am/am.cpp

@@ -31,6 +31,7 @@
 #include "core/hle/service/am/tcap.h"
 #include "core/hle/service/apm/controller.h"
 #include "core/hle/service/apm/interface.h"
+#include "core/hle/service/bcat/backend/backend.h"
 #include "core/hle/service/filesystem/filesystem.h"
 #include "core/hle/service/ns/ns.h"
 #include "core/hle/service/nvflinger/nvflinger.h"
@@ -46,15 +47,20 @@ constexpr ResultCode ERR_NO_DATA_IN_CHANNEL{ErrorModule::AM, 0x2};
 constexpr ResultCode ERR_NO_MESSAGES{ErrorModule::AM, 0x3};
 constexpr ResultCode ERR_SIZE_OUT_OF_BOUNDS{ErrorModule::AM, 0x1F7};
 
-constexpr u32 POP_LAUNCH_PARAMETER_MAGIC = 0xC79497CA;
+enum class LaunchParameterKind : u32 {
+    ApplicationSpecific = 1,
+    AccountPreselectedUser = 2,
+};
 
-struct LaunchParameters {
+constexpr u32 LAUNCH_PARAMETER_ACCOUNT_PRESELECTED_USER_MAGIC = 0xC79497CA;
+
+struct LaunchParameterAccountPreselectedUser {
     u32_le magic;
     u32_le is_account_selected;
     u128 current_user;
     INSERT_PADDING_BYTES(0x70);
 };
-static_assert(sizeof(LaunchParameters) == 0x88);
+static_assert(sizeof(LaunchParameterAccountPreselectedUser) == 0x88);
 
 IWindowController::IWindowController(Core::System& system_)
     : ServiceFramework("IWindowController"), system{system_} {
@@ -1128,26 +1134,55 @@ void IApplicationFunctions::EndBlockingHomeButton(Kernel::HLERequestContext& ctx
 }
 
 void IApplicationFunctions::PopLaunchParameter(Kernel::HLERequestContext& ctx) {
-    LOG_DEBUG(Service_AM, "called");
+    IPC::RequestParser rp{ctx};
+    const auto kind = rp.PopEnum<LaunchParameterKind>();
 
-    LaunchParameters params{};
+    LOG_DEBUG(Service_AM, "called, kind={:08X}", static_cast<u8>(kind));
 
-    params.magic = POP_LAUNCH_PARAMETER_MAGIC;
-    params.is_account_selected = 1;
+    if (kind == LaunchParameterKind::ApplicationSpecific && !launch_popped_application_specific) {
+        const auto backend = BCAT::CreateBackendFromSettings(
+            [this](u64 tid) { return system.GetFileSystemController().GetBCATDirectory(tid); });
+        const auto build_id_full = Core::System::GetInstance().GetCurrentProcessBuildID();
+        u64 build_id{};
+        std::memcpy(&build_id, build_id_full.data(), sizeof(u64));
 
-    Account::ProfileManager profile_manager{};
-    const auto uuid = profile_manager.GetUser(Settings::values.current_user);
-    ASSERT(uuid);
-    params.current_user = uuid->uuid;
+        const auto data =
+            backend->GetLaunchParameter({Core::CurrentProcess()->GetTitleID(), build_id});
 
-    IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+        if (data.has_value()) {
+            IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+            rb.Push(RESULT_SUCCESS);
+            rb.PushIpcInterface<AM::IStorage>(*data);
+            launch_popped_application_specific = true;
+            return;
+        }
+    } else if (kind == LaunchParameterKind::AccountPreselectedUser &&
+               !launch_popped_account_preselect) {
+        LaunchParameterAccountPreselectedUser params{};
 
-    rb.Push(RESULT_SUCCESS);
+        params.magic = LAUNCH_PARAMETER_ACCOUNT_PRESELECTED_USER_MAGIC;
+        params.is_account_selected = 1;
 
-    std::vector<u8> buffer(sizeof(LaunchParameters));
-    std::memcpy(buffer.data(), &params, buffer.size());
+        Account::ProfileManager profile_manager{};
+        const auto uuid = profile_manager.GetUser(Settings::values.current_user);
+        ASSERT(uuid);
+        params.current_user = uuid->uuid;
 
-    rb.PushIpcInterface<AM::IStorage>(buffer);
+        IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+
+        rb.Push(RESULT_SUCCESS);
+
+        std::vector<u8> buffer(sizeof(LaunchParameterAccountPreselectedUser));
+        std::memcpy(buffer.data(), &params, buffer.size());
+
+        rb.PushIpcInterface<AM::IStorage>(buffer);
+        launch_popped_account_preselect = true;
+        return;
+    }
+
+    LOG_ERROR(Service_AM, "Attempted to load launch parameter but none was found!");
+    IPC::ResponseBuilder rb{ctx, 2};
+    rb.Push(ERR_NO_DATA_IN_CHANNEL);
 }
 
 void IApplicationFunctions::CreateApplicationAndRequestToStartForQuest(

src/core/hle/service/am/am.h

@@ -147,6 +147,7 @@ private:
     void GetAccumulatedSuspendedTickValue(Kernel::HLERequestContext& ctx);
     void GetAccumulatedSuspendedTickChangedEvent(Kernel::HLERequestContext& ctx);
 
+    Core::System& system;
     std::shared_ptr<NVFlinger::NVFlinger> nvflinger;
     Kernel::EventPair launchable_event;
     Kernel::EventPair accumulated_suspended_tick_changed_event;
@@ -154,8 +155,6 @@ private:
     u32 idle_time_detection_extension = 0;
     u64 num_fatal_sections_entered = 0;
     bool is_auto_sleep_disabled = false;
-
-    Core::System& system;
 };
 
 class ICommonStateGetter final : public ServiceFramework<ICommonStateGetter> {
@@ -255,6 +254,8 @@ private:
     void EnableApplicationCrashReport(Kernel::HLERequestContext& ctx);
     void GetGpuErrorDetectedSystemEvent(Kernel::HLERequestContext& ctx);
 
+    bool launch_popped_application_specific = false;
+    bool launch_popped_account_preselect = false;
     Kernel::EventPair gpu_error_detected_event;
     Core::System& system;
 };

src/core/hle/service/am/applets/applets.cpp

@@ -157,6 +157,10 @@ AppletManager::AppletManager(Core::System& system_) : system{system_} {}
 
 AppletManager::~AppletManager() = default;
 
+const AppletFrontendSet& AppletManager::GetAppletFrontendSet() const {
+    return frontend;
+}
+
 void AppletManager::SetAppletFrontendSet(AppletFrontendSet set) {
     if (set.parental_controls != nullptr)
         frontend.parental_controls = std::move(set.parental_controls);

src/core/hle/service/am/applets/applets.h

@@ -190,6 +190,8 @@ public:
     explicit AppletManager(Core::System& system_);
     ~AppletManager();
 
+    const AppletFrontendSet& GetAppletFrontendSet() const;
+
     void SetAppletFrontendSet(AppletFrontendSet set);
     void SetDefaultAppletFrontendSet();
     void SetDefaultAppletsIfMissing();

src/core/hle/service/apm/controller.cpp

@@ -13,7 +13,7 @@ constexpr PerformanceConfiguration DEFAULT_PERFORMANCE_CONFIGURATION =
     PerformanceConfiguration::Config7;
 
 Controller::Controller(Core::Timing::CoreTiming& core_timing)
-    : core_timing(core_timing), configs{
+    : core_timing{core_timing}, configs{
                                     {PerformanceMode::Handheld, DEFAULT_PERFORMANCE_CONFIGURATION},
                                     {PerformanceMode::Docked, DEFAULT_PERFORMANCE_CONFIGURATION},
                                 } {}
@@ -63,6 +63,7 @@ PerformanceConfiguration Controller::GetCurrentPerformanceConfiguration(Performa
 void Controller::SetClockSpeed(u32 mhz) {
     LOG_INFO(Service_APM, "called, mhz={:08X}", mhz);
     // TODO(DarkLordZach): Actually signal core_timing to change clock speed.
+    // TODO(Rodrigo): Remove [[maybe_unused]] when core_timing is used.
 }
 
 } // namespace Service::APM

src/core/hle/service/apm/controller.h

@@ -50,7 +50,7 @@ enum class PerformanceMode : u8 {
 // system during times of high load -- this simply maps to different PerformanceConfigs to use.
 class Controller {
 public:
-    Controller(Core::Timing::CoreTiming& core_timing);
+    explicit Controller(Core::Timing::CoreTiming& core_timing);
     ~Controller();
 
     void SetPerformanceConfiguration(PerformanceMode mode, PerformanceConfiguration config);
@@ -62,9 +62,9 @@ public:
 private:
     void SetClockSpeed(u32 mhz);
 
-    std::map<PerformanceMode, PerformanceConfiguration> configs;
+    [[maybe_unused]] Core::Timing::CoreTiming& core_timing;
 
-    Core::Timing::CoreTiming& core_timing;
+    std::map<PerformanceMode, PerformanceConfiguration> configs;
 };
 
 } // namespace Service::APM

src/core/hle/service/audio/audout_u.cpp

@@ -205,7 +205,7 @@ private:
     AudioCore::StreamPtr stream;
     std::string device_name;
 
-    AudoutParams audio_params{};
+    [[maybe_unused]] AudoutParams audio_params {};
 
     /// This is the event handle used to check if the audio buffer was released
     Kernel::EventPair buffer_event;

src/core/hle/service/bcat/backend/backend.cpp

@@ -0,0 +1,136 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/hex_util.h"
+#include "common/logging/log.h"
+#include "core/core.h"
+#include "core/hle/lock.h"
+#include "core/hle/service/bcat/backend/backend.h"
+
+namespace Service::BCAT {
+
+ProgressServiceBackend::ProgressServiceBackend(std::string event_name) : impl{} {
+    auto& kernel{Core::System::GetInstance().Kernel()};
+    event = Kernel::WritableEvent::CreateEventPair(
+        kernel, Kernel::ResetType::Automatic, "ProgressServiceBackend:UpdateEvent:" + event_name);
+}
+
+Kernel::SharedPtr<Kernel::ReadableEvent> ProgressServiceBackend::GetEvent() {
+    return event.readable;
+}
+
+DeliveryCacheProgressImpl& ProgressServiceBackend::GetImpl() {
+    return impl;
+}
+
+void ProgressServiceBackend::SetNeedHLELock(bool need) {
+    need_hle_lock = need;
+}
+
+void ProgressServiceBackend::SetTotalSize(u64 size) {
+    impl.total_bytes = size;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::StartConnecting() {
+    impl.status = DeliveryCacheProgressImpl::Status::Connecting;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::StartProcessingDataList() {
+    impl.status = DeliveryCacheProgressImpl::Status::ProcessingDataList;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::StartDownloadingFile(std::string_view dir_name,
+                                                  std::string_view file_name, u64 file_size) {
+    impl.status = DeliveryCacheProgressImpl::Status::Downloading;
+    impl.current_downloaded_bytes = 0;
+    impl.current_total_bytes = file_size;
+    std::memcpy(impl.current_directory.data(), dir_name.data(),
+                std::min<u64>(dir_name.size(), 0x31ull));
+    std::memcpy(impl.current_file.data(), file_name.data(),
+                std::min<u64>(file_name.size(), 0x31ull));
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::UpdateFileProgress(u64 downloaded) {
+    impl.current_downloaded_bytes = downloaded;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::FinishDownloadingFile() {
+    impl.total_downloaded_bytes += impl.current_total_bytes;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::CommitDirectory(std::string_view dir_name) {
+    impl.status = DeliveryCacheProgressImpl::Status::Committing;
+    impl.current_file.fill(0);
+    impl.current_downloaded_bytes = 0;
+    impl.current_total_bytes = 0;
+    std::memcpy(impl.current_directory.data(), dir_name.data(),
+                std::min<u64>(dir_name.size(), 0x31ull));
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::FinishDownload(ResultCode result) {
+    impl.total_downloaded_bytes = impl.total_bytes;
+    impl.status = DeliveryCacheProgressImpl::Status::Done;
+    impl.result = result;
+    SignalUpdate();
+}
+
+void ProgressServiceBackend::SignalUpdate() const {
+    if (need_hle_lock) {
+        std::lock_guard<std::recursive_mutex> lock(HLE::g_hle_lock);
+        event.writable->Signal();
+    } else {
+        event.writable->Signal();
+    }
+}
+
+Backend::Backend(DirectoryGetter getter) : dir_getter(std::move(getter)) {}
+
+Backend::~Backend() = default;
+
+NullBackend::NullBackend(const DirectoryGetter& getter) : Backend(std::move(getter)) {}
+
+NullBackend::~NullBackend() = default;
+
+bool NullBackend::Synchronize(TitleIDVersion title, ProgressServiceBackend& progress) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, build_id={:016X}", title.title_id,
+              title.build_id);
+
+    progress.FinishDownload(RESULT_SUCCESS);
+    return true;
+}
+
+bool NullBackend::SynchronizeDirectory(TitleIDVersion title, std::string name,
+                                       ProgressServiceBackend& progress) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, build_id={:016X}, name={}", title.title_id,
+              title.build_id, name);
+
+    progress.FinishDownload(RESULT_SUCCESS);
+    return true;
+}
+
+bool NullBackend::Clear(u64 title_id) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}");
+
+    return true;
+}
+
+void NullBackend::SetPassphrase(u64 title_id, const Passphrase& passphrase) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, passphrase = {}", title_id,
+              Common::HexToString(passphrase));
+}
+
+std::optional<std::vector<u8>> NullBackend::GetLaunchParameter(TitleIDVersion title) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, build_id={:016X}", title.title_id,
+              title.build_id);
+    return std::nullopt;
+}
+
+} // namespace Service::BCAT

src/core/hle/service/bcat/backend/backend.h

@@ -0,0 +1,147 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <optional>
+#include "common/common_types.h"
+#include "core/file_sys/vfs_types.h"
+#include "core/hle/kernel/readable_event.h"
+#include "core/hle/kernel/writable_event.h"
+#include "core/hle/result.h"
+
+namespace Service::BCAT {
+
+struct DeliveryCacheProgressImpl;
+
+using DirectoryGetter = std::function<FileSys::VirtualDir(u64)>;
+using Passphrase = std::array<u8, 0x20>;
+
+struct TitleIDVersion {
+    u64 title_id;
+    u64 build_id;
+};
+
+using DirectoryName = std::array<char, 0x20>;
+using FileName = std::array<char, 0x20>;
+
+struct DeliveryCacheProgressImpl {
+    enum class Status : s32 {
+        None = 0x0,
+        Queued = 0x1,
+        Connecting = 0x2,
+        ProcessingDataList = 0x3,
+        Downloading = 0x4,
+        Committing = 0x5,
+        Done = 0x9,
+    };
+
+    Status status;
+    ResultCode result = RESULT_SUCCESS;
+    DirectoryName current_directory;
+    FileName current_file;
+    s64 current_downloaded_bytes; ///< Bytes downloaded on current file.
+    s64 current_total_bytes;      ///< Bytes total on current file.
+    s64 total_downloaded_bytes;   ///< Bytes downloaded on overall download.
+    s64 total_bytes;              ///< Bytes total on overall download.
+    INSERT_PADDING_BYTES(
+        0x198); ///< Appears to be unused in official code, possibly reserved for future use.
+};
+static_assert(sizeof(DeliveryCacheProgressImpl) == 0x200,
+              "DeliveryCacheProgressImpl has incorrect size.");
+
+// A class to manage the signalling to the game about BCAT download progress.
+// Some of this class is implemented in module.cpp to avoid exposing the implementation structure.
+class ProgressServiceBackend {
+    friend class IBcatService;
+
+public:
+    // Clients should call this with true if any of the functions are going to be called from a
+    // non-HLE thread and this class need to lock the hle mutex. (default is false)
+    void SetNeedHLELock(bool need);
+
+    // Sets the number of bytes total in the entire download.
+    void SetTotalSize(u64 size);
+
+    // Notifies the application that the backend has started connecting to the server.
+    void StartConnecting();
+    // Notifies the application that the backend has begun accumulating and processing metadata.
+    void StartProcessingDataList();
+
+    // Notifies the application that a file is starting to be downloaded.
+    void StartDownloadingFile(std::string_view dir_name, std::string_view file_name, u64 file_size);
+    // Updates the progress of the current file to the size passed.
+    void UpdateFileProgress(u64 downloaded);
+    // Notifies the application that the current file has completed download.
+    void FinishDownloadingFile();
+
+    // Notifies the application that all files in this directory have completed and are being
+    // finalized.
+    void CommitDirectory(std::string_view dir_name);
+
+    // Notifies the application that the operation completed with result code result.
+    void FinishDownload(ResultCode result);
+
+private:
+    explicit ProgressServiceBackend(std::string event_name);
+
+    Kernel::SharedPtr<Kernel::ReadableEvent> GetEvent();
+    DeliveryCacheProgressImpl& GetImpl();
+
+    void SignalUpdate() const;
+
+    DeliveryCacheProgressImpl impl;
+    Kernel::EventPair event;
+    bool need_hle_lock = false;
+};
+
+// A class representing an abstract backend for BCAT functionality.
+class Backend {
+public:
+    explicit Backend(DirectoryGetter getter);
+    virtual ~Backend();
+
+    // Called when the backend is needed to synchronize the data for the game with title ID and
+    // version in title. A ProgressServiceBackend object is provided to alert the application of
+    // status.
+    virtual bool Synchronize(TitleIDVersion title, ProgressServiceBackend& progress) = 0;
+    // Very similar to Synchronize, but only for the directory provided. Backends should not alter
+    // the data for any other directories.
+    virtual bool SynchronizeDirectory(TitleIDVersion title, std::string name,
+                                      ProgressServiceBackend& progress) = 0;
+
+    // Removes all cached data associated with title id provided.
+    virtual bool Clear(u64 title_id) = 0;
+
+    // Sets the BCAT Passphrase to be used with the associated title ID.
+    virtual void SetPassphrase(u64 title_id, const Passphrase& passphrase) = 0;
+
+    // Gets the launch parameter used by AM associated with the title ID and version provided.
+    virtual std::optional<std::vector<u8>> GetLaunchParameter(TitleIDVersion title) = 0;
+
+protected:
+    DirectoryGetter dir_getter;
+};
+
+// A backend of BCAT that provides no operation.
+class NullBackend : public Backend {
+public:
+    explicit NullBackend(const DirectoryGetter& getter);
+    ~NullBackend() override;
+
+    bool Synchronize(TitleIDVersion title, ProgressServiceBackend& progress) override;
+    bool SynchronizeDirectory(TitleIDVersion title, std::string name,
+                              ProgressServiceBackend& progress) override;
+
+    bool Clear(u64 title_id) override;
+
+    void SetPassphrase(u64 title_id, const Passphrase& passphrase) override;
+
+    std::optional<std::vector<u8>> GetLaunchParameter(TitleIDVersion title) override;
+};
+
+std::unique_ptr<Backend> CreateBackendFromSettings(DirectoryGetter getter);
+
+} // namespace Service::BCAT

src/core/hle/service/bcat/backend/boxcat.cpp

@@ -0,0 +1,503 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <fmt/ostream.h>
+#include <httplib.h>
+#include <json.hpp>
+#include <mbedtls/sha256.h>
+#include "common/hex_util.h"
+#include "common/logging/backend.h"
+#include "common/logging/log.h"
+#include "core/core.h"
+#include "core/file_sys/vfs.h"
+#include "core/file_sys/vfs_libzip.h"
+#include "core/file_sys/vfs_vector.h"
+#include "core/frontend/applets/error.h"
+#include "core/hle/service/am/applets/applets.h"
+#include "core/hle/service/bcat/backend/boxcat.h"
+#include "core/settings.h"
+
+namespace {
+
+// Prevents conflicts with windows macro called CreateFile
+FileSys::VirtualFile VfsCreateFileWrap(FileSys::VirtualDir dir, std::string_view name) {
+    return dir->CreateFile(name);
+}
+
+// Prevents conflicts with windows macro called DeleteFile
+bool VfsDeleteFileWrap(FileSys::VirtualDir dir, std::string_view name) {
+    return dir->DeleteFile(name);
+}
+
+} // Anonymous namespace
+
+namespace Service::BCAT {
+
+constexpr ResultCode ERROR_GENERAL_BCAT_FAILURE{ErrorModule::BCAT, 1};
+
+constexpr char BOXCAT_HOSTNAME[] = "api.yuzu-emu.org";
+
+// Formatted using fmt with arg[0] = hex title id
+constexpr char BOXCAT_PATHNAME_DATA[] = "/game-assets/{:016X}/boxcat";
+constexpr char BOXCAT_PATHNAME_LAUNCHPARAM[] = "/game-assets/{:016X}/launchparam";
+
+constexpr char BOXCAT_PATHNAME_EVENTS[] = "/game-assets/boxcat/events";
+
+constexpr char BOXCAT_API_VERSION[] = "1";
+constexpr char BOXCAT_CLIENT_TYPE[] = "yuzu";
+
+// HTTP status codes for Boxcat
+enum class ResponseStatus {
+    Ok = 200,               ///< Operation completed successfully.
+    BadClientVersion = 301, ///< The Boxcat-Client-Version doesn't match the server.
+    NoUpdate = 304,         ///< The digest provided would match the new data, no need to update.
+    NoMatchTitleId = 404,   ///< The title ID provided doesn't have a boxcat implementation.
+    NoMatchBuildId = 406,   ///< The build ID provided is blacklisted (potentially because of format
+                            ///< issues or whatnot) and has no data.
+};
+
+enum class DownloadResult {
+    Success = 0,
+    NoResponse,
+    GeneralWebError,
+    NoMatchTitleId,
+    NoMatchBuildId,
+    InvalidContentType,
+    GeneralFSError,
+    BadClientVersion,
+};
+
+constexpr std::array<const char*, 8> DOWNLOAD_RESULT_LOG_MESSAGES{
+    "Success",
+    "There was no response from the server.",
+    "There was a general web error code returned from the server.",
+    "The title ID of the current game doesn't have a boxcat implementation. If you believe an "
+    "implementation should be added, contact yuzu support.",
+    "The build ID of the current version of the game is marked as incompatible with the current "
+    "BCAT distribution. Try upgrading or downgrading your game version or contacting yuzu support.",
+    "The content type of the web response was invalid.",
+    "There was a general filesystem error while saving the zip file.",
+    "The server is either too new or too old to serve the request. Try using the latest version of "
+    "an official release of yuzu.",
+};
+
+std::ostream& operator<<(std::ostream& os, DownloadResult result) {
+    return os << DOWNLOAD_RESULT_LOG_MESSAGES.at(static_cast<std::size_t>(result));
+}
+
+constexpr u32 PORT = 443;
+constexpr u32 TIMEOUT_SECONDS = 30;
+[[maybe_unused]] constexpr u64 VFS_COPY_BLOCK_SIZE = 1ULL << 24; // 4MB
+
+namespace {
+
+std::string GetBINFilePath(u64 title_id) {
+    return fmt::format("{}bcat/{:016X}/launchparam.bin",
+                       FileUtil::GetUserPath(FileUtil::UserPath::CacheDir), title_id);
+}
+
+std::string GetZIPFilePath(u64 title_id) {
+    return fmt::format("{}bcat/{:016X}/data.zip",
+                       FileUtil::GetUserPath(FileUtil::UserPath::CacheDir), title_id);
+}
+
+// If the error is something the user should know about (build ID mismatch, bad client version),
+// display an error.
+void HandleDownloadDisplayResult(DownloadResult res) {
+    if (res == DownloadResult::Success || res == DownloadResult::NoResponse ||
+        res == DownloadResult::GeneralWebError || res == DownloadResult::GeneralFSError ||
+        res == DownloadResult::NoMatchTitleId || res == DownloadResult::InvalidContentType) {
+        return;
+    }
+
+    const auto& frontend{Core::System::GetInstance().GetAppletManager().GetAppletFrontendSet()};
+    frontend.error->ShowCustomErrorText(
+        ResultCode(-1), "There was an error while attempting to use Boxcat.",
+        DOWNLOAD_RESULT_LOG_MESSAGES[static_cast<std::size_t>(res)], [] {});
+}
+
+bool VfsRawCopyProgress(FileSys::VirtualFile src, FileSys::VirtualFile dest,
+                        std::string_view dir_name, ProgressServiceBackend& progress,
+                        std::size_t block_size = 0x1000) {
+    if (src == nullptr || dest == nullptr || !src->IsReadable() || !dest->IsWritable())
+        return false;
+    if (!dest->Resize(src->GetSize()))
+        return false;
+
+    progress.StartDownloadingFile(dir_name, src->GetName(), src->GetSize());
+
+    std::vector<u8> temp(std::min(block_size, src->GetSize()));
+    for (std::size_t i = 0; i < src->GetSize(); i += block_size) {
+        const auto read = std::min(block_size, src->GetSize() - i);
+
+        if (src->Read(temp.data(), read, i) != read) {
+            return false;
+        }
+
+        if (dest->Write(temp.data(), read, i) != read) {
+            return false;
+        }
+
+        progress.UpdateFileProgress(i);
+    }
+
+    progress.FinishDownloadingFile();
+
+    return true;
+}
+
+bool VfsRawCopyDProgressSingle(FileSys::VirtualDir src, FileSys::VirtualDir dest,
+                               ProgressServiceBackend& progress, std::size_t block_size = 0x1000) {
+    if (src == nullptr || dest == nullptr || !src->IsReadable() || !dest->IsWritable())
+        return false;
+
+    for (const auto& file : src->GetFiles()) {
+        const auto out_file = VfsCreateFileWrap(dest, file->GetName());
+        if (!VfsRawCopyProgress(file, out_file, src->GetName(), progress, block_size)) {
+            return false;
+        }
+    }
+    progress.CommitDirectory(src->GetName());
+
+    return true;
+}
+
+bool VfsRawCopyDProgress(FileSys::VirtualDir src, FileSys::VirtualDir dest,
+                         ProgressServiceBackend& progress, std::size_t block_size = 0x1000) {
+    if (src == nullptr || dest == nullptr || !src->IsReadable() || !dest->IsWritable())
+        return false;
+
+    for (const auto& dir : src->GetSubdirectories()) {
+        const auto out = dest->CreateSubdirectory(dir->GetName());
+        if (!VfsRawCopyDProgressSingle(dir, out, progress, block_size)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+} // Anonymous namespace
+
+class Boxcat::Client {
+public:
+    Client(std::string path, u64 title_id, u64 build_id)
+        : path(std::move(path)), title_id(title_id), build_id(build_id) {}
+
+    DownloadResult DownloadDataZip() {
+        return DownloadInternal(fmt::format(BOXCAT_PATHNAME_DATA, title_id), TIMEOUT_SECONDS,
+                                "application/zip");
+    }
+
+    DownloadResult DownloadLaunchParam() {
+        return DownloadInternal(fmt::format(BOXCAT_PATHNAME_LAUNCHPARAM, title_id),
+                                TIMEOUT_SECONDS / 3, "application/octet-stream");
+    }
+
+private:
+    DownloadResult DownloadInternal(const std::string& resolved_path, u32 timeout_seconds,
+                                    const std::string& content_type_name) {
+        if (client == nullptr) {
+            client = std::make_unique<httplib::SSLClient>(BOXCAT_HOSTNAME, PORT, timeout_seconds);
+        }
+
+        httplib::Headers headers{
+            {std::string("Game-Assets-API-Version"), std::string(BOXCAT_API_VERSION)},
+            {std::string("Boxcat-Client-Type"), std::string(BOXCAT_CLIENT_TYPE)},
+            {std::string("Game-Build-Id"), fmt::format("{:016X}", build_id)},
+        };
+
+        if (FileUtil::Exists(path)) {
+            FileUtil::IOFile file{path, "rb"};
+            if (file.IsOpen()) {
+                std::vector<u8> bytes(file.GetSize());
+                file.ReadBytes(bytes.data(), bytes.size());
+                const auto digest = DigestFile(bytes);
+                headers.insert({std::string("If-None-Match"), Common::HexToString(digest, false)});
+            }
+        }
+
+        const auto response = client->Get(resolved_path.c_str(), headers);
+        if (response == nullptr)
+            return DownloadResult::NoResponse;
+
+        if (response->status == static_cast<int>(ResponseStatus::NoUpdate))
+            return DownloadResult::Success;
+        if (response->status == static_cast<int>(ResponseStatus::BadClientVersion))
+            return DownloadResult::BadClientVersion;
+        if (response->status == static_cast<int>(ResponseStatus::NoMatchTitleId))
+            return DownloadResult::NoMatchTitleId;
+        if (response->status == static_cast<int>(ResponseStatus::NoMatchBuildId))
+            return DownloadResult::NoMatchBuildId;
+        if (response->status != static_cast<int>(ResponseStatus::Ok))
+            return DownloadResult::GeneralWebError;
+
+        const auto content_type = response->headers.find("content-type");
+        if (content_type == response->headers.end() ||
+            content_type->second.find(content_type_name) == std::string::npos) {
+            return DownloadResult::InvalidContentType;
+        }
+
+        FileUtil::CreateFullPath(path);
+        FileUtil::IOFile file{path, "wb"};
+        if (!file.IsOpen())
+            return DownloadResult::GeneralFSError;
+        if (!file.Resize(response->body.size()))
+            return DownloadResult::GeneralFSError;
+        if (file.WriteBytes(response->body.data(), response->body.size()) != response->body.size())
+            return DownloadResult::GeneralFSError;
+
+        return DownloadResult::Success;
+    }
+
+    using Digest = std::array<u8, 0x20>;
+    static Digest DigestFile(std::vector<u8> bytes) {
+        Digest out{};
+        mbedtls_sha256(bytes.data(), bytes.size(), out.data(), 0);
+        return out;
+    }
+
+    std::unique_ptr<httplib::Client> client;
+    std::string path;
+    u64 title_id;
+    u64 build_id;
+};
+
+Boxcat::Boxcat(DirectoryGetter getter) : Backend(std::move(getter)) {}
+
+Boxcat::~Boxcat() = default;
+
+void SynchronizeInternal(DirectoryGetter dir_getter, TitleIDVersion title,
+                         ProgressServiceBackend& progress,
+                         std::optional<std::string> dir_name = {}) {
+    progress.SetNeedHLELock(true);
+
+    if (Settings::values.bcat_boxcat_local) {
+        LOG_INFO(Service_BCAT, "Boxcat using local data by override, skipping download.");
+        const auto dir = dir_getter(title.title_id);
+        if (dir)
+            progress.SetTotalSize(dir->GetSize());
+        progress.FinishDownload(RESULT_SUCCESS);
+        return;
+    }
+
+    const auto zip_path{GetZIPFilePath(title.title_id)};
+    Boxcat::Client client{zip_path, title.title_id, title.build_id};
+
+    progress.StartConnecting();
+
+    const auto res = client.DownloadDataZip();
+    if (res != DownloadResult::Success) {
+        LOG_ERROR(Service_BCAT, "Boxcat synchronization failed with error '{}'!", res);
+
+        if (res == DownloadResult::NoMatchBuildId || res == DownloadResult::NoMatchTitleId) {
+            FileUtil::Delete(zip_path);
+        }
+
+        HandleDownloadDisplayResult(res);
+        progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+        return;
+    }
+
+    progress.StartProcessingDataList();
+
+    FileUtil::IOFile zip{zip_path, "rb"};
+    const auto size = zip.GetSize();
+    std::vector<u8> bytes(size);
+    if (!zip.IsOpen() || size == 0 || zip.ReadBytes(bytes.data(), bytes.size()) != bytes.size()) {
+        LOG_ERROR(Service_BCAT, "Boxcat failed to read ZIP file at path '{}'!", zip_path);
+        progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+        return;
+    }
+
+    const auto extracted = FileSys::ExtractZIP(std::make_shared<FileSys::VectorVfsFile>(bytes));
+    if (extracted == nullptr) {
+        LOG_ERROR(Service_BCAT, "Boxcat failed to extract ZIP file!");
+        progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+        return;
+    }
+
+    if (dir_name == std::nullopt) {
+        progress.SetTotalSize(extracted->GetSize());
+
+        const auto target_dir = dir_getter(title.title_id);
+        if (target_dir == nullptr || !VfsRawCopyDProgress(extracted, target_dir, progress)) {
+            LOG_ERROR(Service_BCAT, "Boxcat failed to copy extracted ZIP to target directory!");
+            progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+            return;
+        }
+    } else {
+        const auto target_dir = dir_getter(title.title_id);
+        if (target_dir == nullptr) {
+            LOG_ERROR(Service_BCAT, "Boxcat failed to get directory for title ID!");
+            progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+            return;
+        }
+
+        const auto target_sub = target_dir->GetSubdirectory(*dir_name);
+        const auto source_sub = extracted->GetSubdirectory(*dir_name);
+
+        progress.SetTotalSize(source_sub->GetSize());
+
+        std::vector<std::string> filenames;
+        {
+            const auto files = target_sub->GetFiles();
+            std::transform(files.begin(), files.end(), std::back_inserter(filenames),
+                           [](const auto& vfile) { return vfile->GetName(); });
+        }
+
+        for (const auto& filename : filenames) {
+            VfsDeleteFileWrap(target_sub, filename);
+        }
+
+        if (target_sub == nullptr || source_sub == nullptr ||
+            !VfsRawCopyDProgressSingle(source_sub, target_sub, progress)) {
+            LOG_ERROR(Service_BCAT, "Boxcat failed to copy extracted ZIP to target directory!");
+            progress.FinishDownload(ERROR_GENERAL_BCAT_FAILURE);
+            return;
+        }
+    }
+
+    progress.FinishDownload(RESULT_SUCCESS);
+}
+
+bool Boxcat::Synchronize(TitleIDVersion title, ProgressServiceBackend& progress) {
+    is_syncing.exchange(true);
+    std::thread([this, title, &progress] { SynchronizeInternal(dir_getter, title, progress); })
+        .detach();
+    return true;
+}
+
+bool Boxcat::SynchronizeDirectory(TitleIDVersion title, std::string name,
+                                  ProgressServiceBackend& progress) {
+    is_syncing.exchange(true);
+    std::thread(
+        [this, title, name, &progress] { SynchronizeInternal(dir_getter, title, progress, name); })
+        .detach();
+    return true;
+}
+
+bool Boxcat::Clear(u64 title_id) {
+    if (Settings::values.bcat_boxcat_local) {
+        LOG_INFO(Service_BCAT, "Boxcat using local data by override, skipping clear.");
+        return true;
+    }
+
+    const auto dir = dir_getter(title_id);
+
+    std::vector<std::string> dirnames;
+
+    for (const auto& subdir : dir->GetSubdirectories())
+        dirnames.push_back(subdir->GetName());
+
+    for (const auto& subdir : dirnames) {
+        if (!dir->DeleteSubdirectoryRecursive(subdir))
+            return false;
+    }
+
+    return true;
+}
+
+void Boxcat::SetPassphrase(u64 title_id, const Passphrase& passphrase) {
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, passphrase={}", title_id,
+              Common::HexToString(passphrase));
+}
+
+std::optional<std::vector<u8>> Boxcat::GetLaunchParameter(TitleIDVersion title) {
+    const auto path{GetBINFilePath(title.title_id)};
+
+    if (Settings::values.bcat_boxcat_local) {
+        LOG_INFO(Service_BCAT, "Boxcat using local data by override, skipping download.");
+    } else {
+        Boxcat::Client client{path, title.title_id, title.build_id};
+
+        const auto res = client.DownloadLaunchParam();
+        if (res != DownloadResult::Success) {
+            LOG_ERROR(Service_BCAT, "Boxcat synchronization failed with error '{}'!", res);
+
+            if (res == DownloadResult::NoMatchBuildId || res == DownloadResult::NoMatchTitleId) {
+                FileUtil::Delete(path);
+            }
+
+            HandleDownloadDisplayResult(res);
+            return std::nullopt;
+        }
+    }
+
+    FileUtil::IOFile bin{path, "rb"};
+    const auto size = bin.GetSize();
+    std::vector<u8> bytes(size);
+    if (!bin.IsOpen() || size == 0 || bin.ReadBytes(bytes.data(), bytes.size()) != bytes.size()) {
+        LOG_ERROR(Service_BCAT, "Boxcat failed to read launch parameter binary at path '{}'!",
+                  path);
+        return std::nullopt;
+    }
+
+    return bytes;
+}
+
+Boxcat::StatusResult Boxcat::GetStatus(std::optional<std::string>& global,
+                                       std::map<std::string, EventStatus>& games) {
+    httplib::SSLClient client{BOXCAT_HOSTNAME, static_cast<int>(PORT),
+                              static_cast<int>(TIMEOUT_SECONDS)};
+
+    httplib::Headers headers{
+        {std::string("Game-Assets-API-Version"), std::string(BOXCAT_API_VERSION)},
+        {std::string("Boxcat-Client-Type"), std::string(BOXCAT_CLIENT_TYPE)},
+    };
+
+    const auto response = client.Get(BOXCAT_PATHNAME_EVENTS, headers);
+    if (response == nullptr)
+        return StatusResult::Offline;
+
+    if (response->status == static_cast<int>(ResponseStatus::BadClientVersion))
+        return StatusResult::BadClientVersion;
+
+    try {
+        nlohmann::json json = nlohmann::json::parse(response->body);
+
+        if (!json["online"].get<bool>())
+            return StatusResult::Offline;
+
+        if (json["global"].is_null())
+            global = std::nullopt;
+        else
+            global = json["global"].get<std::string>();
+
+        if (json["games"].is_array()) {
+            for (const auto object : json["games"]) {
+                if (object.is_object() && object.find("name") != object.end()) {
+                    EventStatus detail{};
+                    if (object["header"].is_string()) {
+                        detail.header = object["header"].get<std::string>();
+                    } else {
+                        detail.header = std::nullopt;
+                    }
+
+                    if (object["footer"].is_string()) {
+                        detail.footer = object["footer"].get<std::string>();
+                    } else {
+                        detail.footer = std::nullopt;
+                    }
+
+                    if (object["events"].is_array()) {
+                        for (const auto& event : object["events"]) {
+                            if (!event.is_string())
+                                continue;
+                            detail.events.push_back(event.get<std::string>());
+                        }
+                    }
+
+                    games.insert_or_assign(object["name"], std::move(detail));
+                }
+            }
+        }
+
+        return StatusResult::Success;
+    } catch (const nlohmann::json::parse_error& e) {
+        return StatusResult::ParseError;
+    }
+}
+
+} // namespace Service::BCAT

src/core/hle/service/bcat/backend/boxcat.h

@@ -0,0 +1,58 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <atomic>
+#include <map>
+#include <optional>
+#include "core/hle/service/bcat/backend/backend.h"
+
+namespace Service::BCAT {
+
+struct EventStatus {
+    std::optional<std::string> header;
+    std::optional<std::string> footer;
+    std::vector<std::string> events;
+};
+
+/// Boxcat is yuzu's custom backend implementation of Nintendo's BCAT service. It is free to use and
+/// doesn't require a switch or nintendo account. The content is controlled by the yuzu team.
+class Boxcat final : public Backend {
+    friend void SynchronizeInternal(DirectoryGetter dir_getter, TitleIDVersion title,
+                                    ProgressServiceBackend& progress,
+                                    std::optional<std::string> dir_name);
+
+public:
+    explicit Boxcat(DirectoryGetter getter);
+    ~Boxcat() override;
+
+    bool Synchronize(TitleIDVersion title, ProgressServiceBackend& progress) override;
+    bool SynchronizeDirectory(TitleIDVersion title, std::string name,
+                              ProgressServiceBackend& progress) override;
+
+    bool Clear(u64 title_id) override;
+
+    void SetPassphrase(u64 title_id, const Passphrase& passphrase) override;
+
+    std::optional<std::vector<u8>> GetLaunchParameter(TitleIDVersion title) override;
+
+    enum class StatusResult {
+        Success,
+        Offline,
+        ParseError,
+        BadClientVersion,
+    };
+
+    static StatusResult GetStatus(std::optional<std::string>& global,
+                                  std::map<std::string, EventStatus>& games);
+
+private:
+    std::atomic_bool is_syncing{false};
+
+    class Client;
+    std::unique_ptr<Client> client;
+};
+
+} // namespace Service::BCAT

src/core/hle/service/bcat/bcat.cpp

@@ -6,11 +6,15 @@
 
 namespace Service::BCAT {
 
-BCAT::BCAT(std::shared_ptr<Module> module, const char* name)
-    : Module::Interface(std::move(module), name) {
+BCAT::BCAT(std::shared_ptr<Module> module, FileSystem::FileSystemController& fsc, const char* name)
+    : Module::Interface(std::move(module), fsc, name) {
+    // clang-format off
     static const FunctionInfo functions[] = {
         {0, &BCAT::CreateBcatService, "CreateBcatService"},
+        {1, &BCAT::CreateDeliveryCacheStorageService, "CreateDeliveryCacheStorageService"},
+        {2, &BCAT::CreateDeliveryCacheStorageServiceWithApplicationId, "CreateDeliveryCacheStorageServiceWithApplicationId"},
     };
+    // clang-format on
     RegisterHandlers(functions);
 }
 

src/core/hle/service/bcat/bcat.h

@@ -10,7 +10,8 @@ namespace Service::BCAT {
 
 class BCAT final : public Module::Interface {
 public:
-    explicit BCAT(std::shared_ptr<Module> module, const char* name);
+    explicit BCAT(std::shared_ptr<Module> module, FileSystem::FileSystemController& fsc,
+                  const char* name);
     ~BCAT() override;
 };
 

src/core/hle/service/bcat/module.cpp

@@ -2,34 +2,254 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <cctype>
+#include <mbedtls/md5.h>
+#include "backend/boxcat.h"
+#include "common/hex_util.h"
 #include "common/logging/log.h"
+#include "common/string_util.h"
+#include "core/file_sys/vfs.h"
 #include "core/hle/ipc_helpers.h"
+#include "core/hle/kernel/process.h"
+#include "core/hle/kernel/readable_event.h"
+#include "core/hle/kernel/writable_event.h"
+#include "core/hle/service/bcat/backend/backend.h"
 #include "core/hle/service/bcat/bcat.h"
 #include "core/hle/service/bcat/module.h"
+#include "core/hle/service/filesystem/filesystem.h"
+#include "core/settings.h"
 
 namespace Service::BCAT {
 
+constexpr ResultCode ERROR_INVALID_ARGUMENT{ErrorModule::BCAT, 1};
+constexpr ResultCode ERROR_FAILED_OPEN_ENTITY{ErrorModule::BCAT, 2};
+constexpr ResultCode ERROR_ENTITY_ALREADY_OPEN{ErrorModule::BCAT, 6};
+constexpr ResultCode ERROR_NO_OPEN_ENTITY{ErrorModule::BCAT, 7};
+
+// The command to clear the delivery cache just calls fs IFileSystem DeleteFile on all of the files
+// and if any of them have a non-zero result it just forwards that result. This is the FS error code
+// for permission denied, which is the closest approximation of this scenario.
+constexpr ResultCode ERROR_FAILED_CLEAR_CACHE{ErrorModule::FS, 6400};
+
+using BCATDigest = std::array<u8, 0x10>;
+
+namespace {
+
+u64 GetCurrentBuildID() {
+    const auto& id = Core::System::GetInstance().GetCurrentProcessBuildID();
+    u64 out{};
+    std::memcpy(&out, id.data(), sizeof(u64));
+    return out;
+}
+
+// The digest is only used to determine if a file is unique compared to others of the same name.
+// Since the algorithm isn't ever checked in game, MD5 is safe.
+BCATDigest DigestFile(const FileSys::VirtualFile& file) {
+    BCATDigest out{};
+    const auto bytes = file->ReadAllBytes();
+    mbedtls_md5(bytes.data(), bytes.size(), out.data());
+    return out;
+}
+
+// For a name to be valid it must be non-empty, must have a null terminating character as the final
+// char, can only contain numbers, letters, underscores and a hyphen if directory and a period if
+// file.
+bool VerifyNameValidInternal(Kernel::HLERequestContext& ctx, std::array<char, 0x20> name,
+                             char match_char) {
+    const auto null_chars = std::count(name.begin(), name.end(), 0);
+    const auto bad_chars = std::count_if(name.begin(), name.end(), [match_char](char c) {
+        return !std::isalnum(static_cast<u8>(c)) && c != '_' && c != match_char && c != '\0';
+    });
+    if (null_chars == 0x20 || null_chars == 0 || bad_chars != 0 || name[0x1F] != '\0') {
+        LOG_ERROR(Service_BCAT, "Name passed was invalid!");
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(ERROR_INVALID_ARGUMENT);
+        return false;
+    }
+
+    return true;
+}
+
+bool VerifyNameValidDir(Kernel::HLERequestContext& ctx, DirectoryName name) {
+    return VerifyNameValidInternal(ctx, name, '-');
+}
+
+bool VerifyNameValidFile(Kernel::HLERequestContext& ctx, FileName name) {
+    return VerifyNameValidInternal(ctx, name, '.');
+}
+
+} // Anonymous namespace
+
+struct DeliveryCacheDirectoryEntry {
+    FileName name;
+    u64 size;
+    BCATDigest digest;
+};
+
+class IDeliveryCacheProgressService final : public ServiceFramework<IDeliveryCacheProgressService> {
+public:
+    IDeliveryCacheProgressService(Kernel::SharedPtr<Kernel::ReadableEvent> event,
+                                  const DeliveryCacheProgressImpl& impl)
+        : ServiceFramework{"IDeliveryCacheProgressService"}, event(std::move(event)), impl(impl) {
+        // clang-format off
+        static const FunctionInfo functions[] = {
+            {0, &IDeliveryCacheProgressService::GetEvent, "GetEvent"},
+            {1, &IDeliveryCacheProgressService::GetImpl, "GetImpl"},
+        };
+        // clang-format on
+
+        RegisterHandlers(functions);
+    }
+
+private:
+    void GetEvent(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        IPC::ResponseBuilder rb{ctx, 2, 1};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushCopyObjects(event);
+    }
+
+    void GetImpl(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        ctx.WriteBuffer(&impl, sizeof(DeliveryCacheProgressImpl));
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    Kernel::SharedPtr<Kernel::ReadableEvent> event;
+    const DeliveryCacheProgressImpl& impl;
+};
+
 class IBcatService final : public ServiceFramework<IBcatService> {
 public:
-    IBcatService() : ServiceFramework("IBcatService") {
+    IBcatService(Backend& backend) : ServiceFramework("IBcatService"), backend(backend) {
+        // clang-format off
         static const FunctionInfo functions[] = {
-            {10100, nullptr, "RequestSyncDeliveryCache"},
-            {10101, nullptr, "RequestSyncDeliveryCacheWithDirectoryName"},
+            {10100, &IBcatService::RequestSyncDeliveryCache, "RequestSyncDeliveryCache"},
+            {10101, &IBcatService::RequestSyncDeliveryCacheWithDirectoryName, "RequestSyncDeliveryCacheWithDirectoryName"},
             {10200, nullptr, "CancelSyncDeliveryCacheRequest"},
             {20100, nullptr, "RequestSyncDeliveryCacheWithApplicationId"},
             {20101, nullptr, "RequestSyncDeliveryCacheWithApplicationIdAndDirectoryName"},
-            {30100, nullptr, "SetPassphrase"},
+            {30100, &IBcatService::SetPassphrase, "SetPassphrase"},
             {30200, nullptr, "RegisterBackgroundDeliveryTask"},
             {30201, nullptr, "UnregisterBackgroundDeliveryTask"},
             {30202, nullptr, "BlockDeliveryTask"},
             {30203, nullptr, "UnblockDeliveryTask"},
             {90100, nullptr, "EnumerateBackgroundDeliveryTask"},
             {90200, nullptr, "GetDeliveryList"},
-            {90201, nullptr, "ClearDeliveryCacheStorage"},
+            {90201, &IBcatService::ClearDeliveryCacheStorage, "ClearDeliveryCacheStorage"},
             {90300, nullptr, "GetPushNotificationLog"},
         };
+        // clang-format on
         RegisterHandlers(functions);
     }
+
+private:
+    enum class SyncType {
+        Normal,
+        Directory,
+        Count,
+    };
+
+    std::shared_ptr<IDeliveryCacheProgressService> CreateProgressService(SyncType type) {
+        auto& backend{progress.at(static_cast<std::size_t>(type))};
+        return std::make_shared<IDeliveryCacheProgressService>(backend.GetEvent(),
+                                                               backend.GetImpl());
+    }
+
+    void RequestSyncDeliveryCache(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        backend.Synchronize({Core::CurrentProcess()->GetTitleID(), GetCurrentBuildID()},
+                            progress.at(static_cast<std::size_t>(SyncType::Normal)));
+
+        IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushIpcInterface(CreateProgressService(SyncType::Normal));
+    }
+
+    void RequestSyncDeliveryCacheWithDirectoryName(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto name_raw = rp.PopRaw<DirectoryName>();
+        const auto name =
+            Common::StringFromFixedZeroTerminatedBuffer(name_raw.data(), name_raw.size());
+
+        LOG_DEBUG(Service_BCAT, "called, name={}", name);
+
+        backend.SynchronizeDirectory({Core::CurrentProcess()->GetTitleID(), GetCurrentBuildID()},
+                                     name,
+                                     progress.at(static_cast<std::size_t>(SyncType::Directory)));
+
+        IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushIpcInterface(CreateProgressService(SyncType::Directory));
+    }
+
+    void SetPassphrase(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto title_id = rp.PopRaw<u64>();
+
+        const auto passphrase_raw = ctx.ReadBuffer();
+
+        LOG_DEBUG(Service_BCAT, "called, title_id={:016X}, passphrase={}", title_id,
+                  Common::HexToString(passphrase_raw));
+
+        if (title_id == 0) {
+            LOG_ERROR(Service_BCAT, "Invalid title ID!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ARGUMENT);
+        }
+
+        if (passphrase_raw.size() > 0x40) {
+            LOG_ERROR(Service_BCAT, "Passphrase too large!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ARGUMENT);
+            return;
+        }
+
+        Passphrase passphrase{};
+        std::memcpy(passphrase.data(), passphrase_raw.data(),
+                    std::min(passphrase.size(), passphrase_raw.size()));
+
+        backend.SetPassphrase(title_id, passphrase);
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    void ClearDeliveryCacheStorage(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto title_id = rp.PopRaw<u64>();
+
+        LOG_DEBUG(Service_BCAT, "called, title_id={:016X}", title_id);
+
+        if (title_id == 0) {
+            LOG_ERROR(Service_BCAT, "Invalid title ID!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ARGUMENT);
+            return;
+        }
+
+        if (!backend.Clear(title_id)) {
+            LOG_ERROR(Service_BCAT, "Could not clear the directory successfully!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_FAILED_CLEAR_CACHE);
+            return;
+        }
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    Backend& backend;
+
+    std::array<ProgressServiceBackend, static_cast<std::size_t>(SyncType::Count)> progress{
+        ProgressServiceBackend{"Normal"},
+        ProgressServiceBackend{"Directory"},
+    };
 };
 
 void Module::Interface::CreateBcatService(Kernel::HLERequestContext& ctx) {
@@ -37,20 +257,331 @@ void Module::Interface::CreateBcatService(Kernel::HLERequestContext& ctx) {
 
     IPC::ResponseBuilder rb{ctx, 2, 0, 1};
     rb.Push(RESULT_SUCCESS);
-    rb.PushIpcInterface<IBcatService>();
+    rb.PushIpcInterface<IBcatService>(*backend);
 }
 
-Module::Interface::Interface(std::shared_ptr<Module> module, const char* name)
-    : ServiceFramework(name), module(std::move(module)) {}
+class IDeliveryCacheFileService final : public ServiceFramework<IDeliveryCacheFileService> {
+public:
+    IDeliveryCacheFileService(FileSys::VirtualDir root_)
+        : ServiceFramework{"IDeliveryCacheFileService"}, root(std::move(root_)) {
+        // clang-format off
+        static const FunctionInfo functions[] = {
+            {0, &IDeliveryCacheFileService::Open, "Open"},
+            {1, &IDeliveryCacheFileService::Read, "Read"},
+            {2, &IDeliveryCacheFileService::GetSize, "GetSize"},
+            {3, &IDeliveryCacheFileService::GetDigest, "GetDigest"},
+        };
+        // clang-format on
+
+        RegisterHandlers(functions);
+    }
+
+private:
+    void Open(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto dir_name_raw = rp.PopRaw<DirectoryName>();
+        const auto file_name_raw = rp.PopRaw<FileName>();
+
+        const auto dir_name =
+            Common::StringFromFixedZeroTerminatedBuffer(dir_name_raw.data(), dir_name_raw.size());
+        const auto file_name =
+            Common::StringFromFixedZeroTerminatedBuffer(file_name_raw.data(), file_name_raw.size());
+
+        LOG_DEBUG(Service_BCAT, "called, dir_name={}, file_name={}", dir_name, file_name);
+
+        if (!VerifyNameValidDir(ctx, dir_name_raw) || !VerifyNameValidFile(ctx, file_name_raw))
+            return;
+
+        if (current_file != nullptr) {
+            LOG_ERROR(Service_BCAT, "A file has already been opened on this interface!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_ENTITY_ALREADY_OPEN);
+            return;
+        }
+
+        const auto dir = root->GetSubdirectory(dir_name);
+
+        if (dir == nullptr) {
+            LOG_ERROR(Service_BCAT, "The directory of name={} couldn't be opened!", dir_name);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_FAILED_OPEN_ENTITY);
+            return;
+        }
+
+        current_file = dir->GetFile(file_name);
+
+        if (current_file == nullptr) {
+            LOG_ERROR(Service_BCAT, "The file of name={} couldn't be opened!", file_name);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_FAILED_OPEN_ENTITY);
+            return;
+        }
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    void Read(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto offset{rp.PopRaw<u64>()};
+
+        auto size = ctx.GetWriteBufferSize();
+
+        LOG_DEBUG(Service_BCAT, "called, offset={:016X}, size={:016X}", offset, size);
+
+        if (current_file == nullptr) {
+            LOG_ERROR(Service_BCAT, "There is no file currently open!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NO_OPEN_ENTITY);
+        }
+
+        size = std::min<u64>(current_file->GetSize() - offset, size);
+        const auto buffer = current_file->ReadBytes(size, offset);
+        ctx.WriteBuffer(buffer);
+
+        IPC::ResponseBuilder rb{ctx, 4};
+        rb.Push(RESULT_SUCCESS);
+        rb.Push<u64>(buffer.size());
+    }
+
+    void GetSize(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        if (current_file == nullptr) {
+            LOG_ERROR(Service_BCAT, "There is no file currently open!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NO_OPEN_ENTITY);
+        }
+
+        IPC::ResponseBuilder rb{ctx, 4};
+        rb.Push(RESULT_SUCCESS);
+        rb.Push<u64>(current_file->GetSize());
+    }
+
+    void GetDigest(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        if (current_file == nullptr) {
+            LOG_ERROR(Service_BCAT, "There is no file currently open!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NO_OPEN_ENTITY);
+        }
+
+        IPC::ResponseBuilder rb{ctx, 6};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushRaw(DigestFile(current_file));
+    }
+
+    FileSys::VirtualDir root;
+    FileSys::VirtualFile current_file;
+};
+
+class IDeliveryCacheDirectoryService final
+    : public ServiceFramework<IDeliveryCacheDirectoryService> {
+public:
+    IDeliveryCacheDirectoryService(FileSys::VirtualDir root_)
+        : ServiceFramework{"IDeliveryCacheDirectoryService"}, root(std::move(root_)) {
+        // clang-format off
+        static const FunctionInfo functions[] = {
+            {0, &IDeliveryCacheDirectoryService::Open, "Open"},
+            {1, &IDeliveryCacheDirectoryService::Read, "Read"},
+            {2, &IDeliveryCacheDirectoryService::GetCount, "GetCount"},
+        };
+        // clang-format on
+
+        RegisterHandlers(functions);
+    }
+
+private:
+    void Open(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        const auto name_raw = rp.PopRaw<DirectoryName>();
+        const auto name =
+            Common::StringFromFixedZeroTerminatedBuffer(name_raw.data(), name_raw.size());
+
+        LOG_DEBUG(Service_BCAT, "called, name={}", name);
+
+        if (!VerifyNameValidDir(ctx, name_raw))
+            return;
+
+        if (current_dir != nullptr) {
+            LOG_ERROR(Service_BCAT, "A file has already been opened on this interface!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_ENTITY_ALREADY_OPEN);
+            return;
+        }
+
+        current_dir = root->GetSubdirectory(name);
+
+        if (current_dir == nullptr) {
+            LOG_ERROR(Service_BCAT, "Failed to open the directory name={}!", name);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_FAILED_OPEN_ENTITY);
+            return;
+        }
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    void Read(Kernel::HLERequestContext& ctx) {
+        auto write_size = ctx.GetWriteBufferSize() / sizeof(DeliveryCacheDirectoryEntry);
+
+        LOG_DEBUG(Service_BCAT, "called, write_size={:016X}", write_size);
+
+        if (current_dir == nullptr) {
+            LOG_ERROR(Service_BCAT, "There is no open directory!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NO_OPEN_ENTITY);
+            return;
+        }
+
+        const auto files = current_dir->GetFiles();
+        write_size = std::min<u64>(write_size, files.size());
+        std::vector<DeliveryCacheDirectoryEntry> entries(write_size);
+        std::transform(
+            files.begin(), files.begin() + write_size, entries.begin(), [](const auto& file) {
+                FileName name{};
+                std::memcpy(name.data(), file->GetName().data(),
+                            std::min(file->GetName().size(), name.size()));
+                return DeliveryCacheDirectoryEntry{name, file->GetSize(), DigestFile(file)};
+            });
+
+        ctx.WriteBuffer(entries);
+
+        IPC::ResponseBuilder rb{ctx, 3};
+        rb.Push(RESULT_SUCCESS);
+        rb.Push<u32>(write_size * sizeof(DeliveryCacheDirectoryEntry));
+    }
+
+    void GetCount(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        if (current_dir == nullptr) {
+            LOG_ERROR(Service_BCAT, "There is no open directory!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NO_OPEN_ENTITY);
+            return;
+        }
+
+        const auto files = current_dir->GetFiles();
+
+        IPC::ResponseBuilder rb{ctx, 3};
+        rb.Push(RESULT_SUCCESS);
+        rb.Push<u32>(files.size());
+    }
+
+    FileSys::VirtualDir root;
+    FileSys::VirtualDir current_dir;
+};
+
+class IDeliveryCacheStorageService final : public ServiceFramework<IDeliveryCacheStorageService> {
+public:
+    IDeliveryCacheStorageService(FileSys::VirtualDir root_)
+        : ServiceFramework{"IDeliveryCacheStorageService"}, root(std::move(root_)) {
+        // clang-format off
+        static const FunctionInfo functions[] = {
+            {0, &IDeliveryCacheStorageService::CreateFileService, "CreateFileService"},
+            {1, &IDeliveryCacheStorageService::CreateDirectoryService, "CreateDirectoryService"},
+            {10, &IDeliveryCacheStorageService::EnumerateDeliveryCacheDirectory, "EnumerateDeliveryCacheDirectory"},
+        };
+        // clang-format on
+
+        RegisterHandlers(functions);
+
+        for (const auto& subdir : root->GetSubdirectories()) {
+            DirectoryName name{};
+            std::memcpy(name.data(), subdir->GetName().data(),
+                        std::min(sizeof(DirectoryName) - 1, subdir->GetName().size()));
+            entries.push_back(name);
+        }
+    }
+
+private:
+    void CreateFileService(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushIpcInterface<IDeliveryCacheFileService>(root);
+    }
+
+    void CreateDirectoryService(Kernel::HLERequestContext& ctx) {
+        LOG_DEBUG(Service_BCAT, "called");
+
+        IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+        rb.Push(RESULT_SUCCESS);
+        rb.PushIpcInterface<IDeliveryCacheDirectoryService>(root);
+    }
+
+    void EnumerateDeliveryCacheDirectory(Kernel::HLERequestContext& ctx) {
+        auto size = ctx.GetWriteBufferSize() / sizeof(DirectoryName);
+
+        LOG_DEBUG(Service_BCAT, "called, size={:016X}", size);
+
+        size = std::min<u64>(size, entries.size() - next_read_index);
+        ctx.WriteBuffer(entries.data() + next_read_index, size * sizeof(DirectoryName));
+        next_read_index += size;
+
+        IPC::ResponseBuilder rb{ctx, 3};
+        rb.Push(RESULT_SUCCESS);
+        rb.Push<u32>(size);
+    }
+
+    FileSys::VirtualDir root;
+    std::vector<DirectoryName> entries;
+    u64 next_read_index = 0;
+};
+
+void Module::Interface::CreateDeliveryCacheStorageService(Kernel::HLERequestContext& ctx) {
+    LOG_DEBUG(Service_BCAT, "called");
+
+    IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+    rb.Push(RESULT_SUCCESS);
+    rb.PushIpcInterface<IDeliveryCacheStorageService>(
+        fsc.GetBCATDirectory(Core::CurrentProcess()->GetTitleID()));
+}
+
+void Module::Interface::CreateDeliveryCacheStorageServiceWithApplicationId(
+    Kernel::HLERequestContext& ctx) {
+    IPC::RequestParser rp{ctx};
+    const auto title_id = rp.PopRaw<u64>();
+
+    LOG_DEBUG(Service_BCAT, "called, title_id={:016X}", title_id);
+
+    IPC::ResponseBuilder rb{ctx, 2, 0, 1};
+    rb.Push(RESULT_SUCCESS);
+    rb.PushIpcInterface<IDeliveryCacheStorageService>(fsc.GetBCATDirectory(title_id));
+}
+
+std::unique_ptr<Backend> CreateBackendFromSettings(DirectoryGetter getter) {
+    const auto backend = Settings::values.bcat_backend;
+
+#ifdef YUZU_ENABLE_BOXCAT
+    if (backend == "boxcat")
+        return std::make_unique<Boxcat>(std::move(getter));
+#endif
+
+    return std::make_unique<NullBackend>(std::move(getter));
+}
+
+Module::Interface::Interface(std::shared_ptr<Module> module, FileSystem::FileSystemController& fsc,
+                             const char* name)
+    : ServiceFramework(name), fsc(fsc), module(std::move(module)),
+      backend(CreateBackendFromSettings([&fsc](u64 tid) { return fsc.GetBCATDirectory(tid); })) {}
 
 Module::Interface::~Interface() = default;
 
-void InstallInterfaces(SM::ServiceManager& service_manager) {
+void InstallInterfaces(Core::System& system) {
     auto module = std::make_shared<Module>();
-    std::make_shared<BCAT>(module, "bcat:a")->InstallAsService(service_manager);
-    std::make_shared<BCAT>(module, "bcat:m")->InstallAsService(service_manager);
-    std::make_shared<BCAT>(module, "bcat:u")->InstallAsService(service_manager);
-    std::make_shared<BCAT>(module, "bcat:s")->InstallAsService(service_manager);
+    std::make_shared<BCAT>(module, system.GetFileSystemController(), "bcat:a")
+        ->InstallAsService(system.ServiceManager());
+    std::make_shared<BCAT>(module, system.GetFileSystemController(), "bcat:m")
+        ->InstallAsService(system.ServiceManager());
+    std::make_shared<BCAT>(module, system.GetFileSystemController(), "bcat:u")
+        ->InstallAsService(system.ServiceManager());
+    std::make_shared<BCAT>(module, system.GetFileSystemController(), "bcat:s")
+        ->InstallAsService(system.ServiceManager());
 }
 
 } // namespace Service::BCAT

src/core/hle/service/bcat/module.h

@@ -6,23 +6,39 @@
 
 #include "core/hle/service/service.h"
 
-namespace Service::BCAT {
+namespace Service {
+
+namespace FileSystem {
+class FileSystemController;
+} // namespace FileSystem
+
+namespace BCAT {
+
+class Backend;
 
 class Module final {
 public:
     class Interface : public ServiceFramework<Interface> {
     public:
-        explicit Interface(std::shared_ptr<Module> module, const char* name);
+        explicit Interface(std::shared_ptr<Module> module, FileSystem::FileSystemController& fsc,
+                           const char* name);
         ~Interface() override;
 
         void CreateBcatService(Kernel::HLERequestContext& ctx);
+        void CreateDeliveryCacheStorageService(Kernel::HLERequestContext& ctx);
+        void CreateDeliveryCacheStorageServiceWithApplicationId(Kernel::HLERequestContext& ctx);
 
     protected:
+        FileSystem::FileSystemController& fsc;
+
         std::shared_ptr<Module> module;
+        std::unique_ptr<Backend> backend;
     };
 };
 
 /// Registers all BCAT services with the specified service manager.
-void InstallInterfaces(SM::ServiceManager& service_manager);
+void InstallInterfaces(Core::System& system);
 
-} // namespace Service::BCAT
+} // namespace BCAT
+
+} // namespace Service

src/core/hle/service/filesystem/filesystem.cpp

@@ -674,6 +674,15 @@ FileSys::VirtualDir FileSystemController::GetModificationDumpRoot(u64 title_id)
     return bis_factory->GetModificationDumpRoot(title_id);
 }
 
+FileSys::VirtualDir FileSystemController::GetBCATDirectory(u64 title_id) const {
+    LOG_TRACE(Service_FS, "Opening BCAT root for tid={:016X}", title_id);
+
+    if (bis_factory == nullptr)
+        return nullptr;
+
+    return bis_factory->GetBCATDirectory(title_id);
+}
+
 void FileSystemController::CreateFactories(FileSys::VfsFilesystem& vfs, bool overwrite) {
     if (overwrite) {
         bis_factory = nullptr;

src/core/hle/service/filesystem/filesystem.h

@@ -110,6 +110,8 @@ public:
     FileSys::VirtualDir GetModificationLoadRoot(u64 title_id) const;
     FileSys::VirtualDir GetModificationDumpRoot(u64 title_id) const;
 
+    FileSys::VirtualDir GetBCATDirectory(u64 title_id) const;
+
     // Creates the SaveData, SDMC, and BIS Factories. Should be called once and before any function
     // above is called.
     void CreateFactories(FileSys::VfsFilesystem& vfs, bool overwrite = true);

src/core/hle/service/filesystem/fsp_srv.cpp

@@ -803,7 +803,7 @@ void FSP_SRV::CreateSaveDataFileSystem(Kernel::HLERequestContext& ctx) {
     IPC::RequestParser rp{ctx};
 
     auto save_struct = rp.PopRaw<FileSys::SaveDataDescriptor>();
-    auto save_create_struct = rp.PopRaw<std::array<u8, 0x40>>();
+    [[maybe_unused]] auto save_create_struct = rp.PopRaw<std::array<u8, 0x40>>();
     u128 uid = rp.PopRaw<u128>();
 
     LOG_DEBUG(Service_FS, "called save_struct = {}, uid = {:016X}{:016X}", save_struct.DebugInfo(),

src/core/hle/service/friend/friend.cpp

@@ -237,7 +237,6 @@ private:
     };
 
     Common::UUID uuid;
-    bool is_event_created = false;
     Kernel::EventPair notification_event;
     std::queue<SizedNotificationInfo> notifications;
     States states{};

src/core/hle/service/hid/controllers/debug_pad.cpp

@@ -11,11 +11,10 @@
 namespace Service::HID {
 
 constexpr s32 HID_JOYSTICK_MAX = 0x7fff;
-constexpr s32 HID_JOYSTICK_MIN = -0x7fff;
+[[maybe_unused]] constexpr s32 HID_JOYSTICK_MIN = -0x7fff;
 enum class JoystickId : std::size_t { Joystick_Left, Joystick_Right };
 
-Controller_DebugPad::Controller_DebugPad(Core::System& system)
-    : ControllerBase(system), system(system) {}
+Controller_DebugPad::Controller_DebugPad(Core::System& system) : ControllerBase(system) {}
 Controller_DebugPad::~Controller_DebugPad() = default;
 
 void Controller_DebugPad::OnInit() {}

src/core/hle/service/hid/controllers/debug_pad.h

@@ -89,6 +89,5 @@ private:
         buttons;
     std::array<std::unique_ptr<Input::AnalogDevice>, Settings::NativeAnalog::NUM_STICKS_HID>
         analogs;
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/gesture.cpp

@@ -10,8 +10,7 @@
 namespace Service::HID {
 constexpr std::size_t SHARED_MEMORY_OFFSET = 0x3BA00;
 
-Controller_Gesture::Controller_Gesture(Core::System& system)
-    : ControllerBase(system), system(system) {}
+Controller_Gesture::Controller_Gesture(Core::System& system) : ControllerBase(system) {}
 Controller_Gesture::~Controller_Gesture() = default;
 
 void Controller_Gesture::OnInit() {}

src/core/hle/service/hid/controllers/gesture.h

@@ -59,6 +59,5 @@ private:
         std::array<GestureState, 17> gesture_states;
     };
     SharedMemory shared_memory{};
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/keyboard.cpp

@@ -12,8 +12,7 @@ namespace Service::HID {
 constexpr std::size_t SHARED_MEMORY_OFFSET = 0x3800;
 constexpr u8 KEYS_PER_BYTE = 8;
 
-Controller_Keyboard::Controller_Keyboard(Core::System& system)
-    : ControllerBase(system), system(system) {}
+Controller_Keyboard::Controller_Keyboard(Core::System& system) : ControllerBase(system) {}
 Controller_Keyboard::~Controller_Keyboard() = default;
 
 void Controller_Keyboard::OnInit() {}

src/core/hle/service/hid/controllers/keyboard.h

@@ -53,6 +53,5 @@ private:
         keyboard_keys;
     std::array<std::unique_ptr<Input::ButtonDevice>, Settings::NativeKeyboard::NumKeyboardMods>
         keyboard_mods;
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/mouse.cpp

@@ -11,7 +11,7 @@
 namespace Service::HID {
 constexpr std::size_t SHARED_MEMORY_OFFSET = 0x3400;
 
-Controller_Mouse::Controller_Mouse(Core::System& system) : ControllerBase(system), system(system) {}
+Controller_Mouse::Controller_Mouse(Core::System& system) : ControllerBase(system) {}
 Controller_Mouse::~Controller_Mouse() = default;
 
 void Controller_Mouse::OnInit() {}

src/core/hle/service/hid/controllers/mouse.h

@@ -53,6 +53,5 @@ private:
     std::unique_ptr<Input::MouseDevice> mouse_device;
     std::array<std::unique_ptr<Input::ButtonDevice>, Settings::NativeMouseButton::NumMouseButtons>
         mouse_button_devices;
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/npad.cpp

@@ -20,7 +20,7 @@
 
 namespace Service::HID {
 constexpr s32 HID_JOYSTICK_MAX = 0x7fff;
-constexpr s32 HID_JOYSTICK_MIN = -0x7fff;
+[[maybe_unused]] constexpr s32 HID_JOYSTICK_MIN = -0x7fff;
 constexpr std::size_t NPAD_OFFSET = 0x9A00;
 constexpr u32 BATTERY_FULL = 2;
 constexpr u32 MAX_NPAD_ID = 7;
@@ -105,6 +105,8 @@ void Controller_NPad::InitNewlyAddedControler(std::size_t controller_idx) {
     controller.joy_styles.raw = 0; // Zero out
     controller.device_type.raw = 0;
     switch (controller_type) {
+    case NPadControllerType::None:
+        UNREACHABLE();
     case NPadControllerType::Handheld:
         controller.joy_styles.handheld.Assign(1);
         controller.device_type.handheld.Assign(1);
@@ -239,7 +241,7 @@ void Controller_NPad::OnRelease() {}
 
 void Controller_NPad::RequestPadStateUpdate(u32 npad_id) {
     const auto controller_idx = NPadIdToIndex(npad_id);
-    const auto controller_type = connected_controllers[controller_idx].type;
+    [[maybe_unused]] const auto controller_type = connected_controllers[controller_idx].type;
     if (!connected_controllers[controller_idx].is_connected) {
         return;
     }
@@ -346,6 +348,8 @@ void Controller_NPad::OnUpdate(const Core::Timing::CoreTiming& core_timing, u8*
         libnx_entry.connection_status.raw = 0;
 
         switch (controller_type) {
+        case NPadControllerType::None:
+            UNREACHABLE();
         case NPadControllerType::Handheld:
             handheld_entry.connection_status.raw = 0;
             handheld_entry.connection_status.IsWired.Assign(1);

src/core/hle/service/hid/controllers/stubbed.cpp

@@ -9,8 +9,7 @@
 
 namespace Service::HID {
 
-Controller_Stubbed::Controller_Stubbed(Core::System& system)
-    : ControllerBase(system), system(system) {}
+Controller_Stubbed::Controller_Stubbed(Core::System& system) : ControllerBase(system) {}
 Controller_Stubbed::~Controller_Stubbed() = default;
 
 void Controller_Stubbed::OnInit() {}

src/core/hle/service/hid/controllers/stubbed.h

@@ -30,6 +30,5 @@ public:
 private:
     bool smart_update{};
     std::size_t common_offset{};
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/touchscreen.cpp

@@ -13,8 +13,7 @@
 namespace Service::HID {
 constexpr std::size_t SHARED_MEMORY_OFFSET = 0x400;
 
-Controller_Touchscreen::Controller_Touchscreen(Core::System& system)
-    : ControllerBase(system), system(system) {}
+Controller_Touchscreen::Controller_Touchscreen(Core::System& system) : ControllerBase(system) {}
 Controller_Touchscreen::~Controller_Touchscreen() = default;
 
 void Controller_Touchscreen::OnInit() {}

src/core/hle/service/hid/controllers/touchscreen.h

@@ -69,6 +69,5 @@ private:
     TouchScreenSharedMemory shared_memory{};
     std::unique_ptr<Input::TouchDevice> touch_device;
     s64_le last_touch{};
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/controllers/xpad.cpp

@@ -10,7 +10,7 @@
 namespace Service::HID {
 constexpr std::size_t SHARED_MEMORY_OFFSET = 0x3C00;
 
-Controller_XPad::Controller_XPad(Core::System& system) : ControllerBase(system), system(system) {}
+Controller_XPad::Controller_XPad(Core::System& system) : ControllerBase(system) {}
 Controller_XPad::~Controller_XPad() = default;
 
 void Controller_XPad::OnInit() {}

src/core/hle/service/hid/controllers/xpad.h

@@ -56,6 +56,5 @@ private:
     };
     static_assert(sizeof(SharedMemory) == 0x1000, "SharedMemory is an invalid size");
     SharedMemory shared_memory{};
-    Core::System& system;
 };
 } // namespace Service::HID

src/core/hle/service/hid/hid.cpp

@@ -38,8 +38,10 @@ namespace Service::HID {
 // Updating period for each HID device.
 // TODO(ogniK): Find actual polling rate of hid
 constexpr s64 pad_update_ticks = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 66);
-constexpr s64 accelerometer_update_ticks = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 100);
-constexpr s64 gyroscope_update_ticks = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 100);
+[[maybe_unused]] constexpr s64 accelerometer_update_ticks =
+    static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 100);
+[[maybe_unused]] constexpr s64 gyroscope_update_ticks =
+    static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 100);
 constexpr std::size_t SHARED_MEMORY_SIZE = 0x40000;
 
 IAppletResource::IAppletResource(Core::System& system)

src/core/hle/service/nfp/nfp.cpp

@@ -18,8 +18,8 @@
 namespace Service::NFP {
 
 namespace ErrCodes {
-constexpr ResultCode ERR_TAG_FAILED(ErrorModule::NFP,
-                                    -1); // TODO(ogniK): Find the actual error code
+[[maybe_unused]] constexpr ResultCode ERR_TAG_FAILED(ErrorModule::NFP,
+                                                     -1); // TODO(ogniK): Find the actual error code
 constexpr ResultCode ERR_NO_APPLICATION_AREA(ErrorModule::NFP, 152);
 } // namespace ErrCodes
 
@@ -35,7 +35,7 @@ Module::Interface::~Interface() = default;
 class IUser final : public ServiceFramework<IUser> {
 public:
     IUser(Module::Interface& nfp_interface, Core::System& system)
-        : ServiceFramework("NFP::IUser"), nfp_interface(nfp_interface), system(system) {
+        : ServiceFramework("NFP::IUser"), nfp_interface(nfp_interface) {
         static const FunctionInfo functions[] = {
             {0, &IUser::Initialize, "Initialize"},
             {1, &IUser::Finalize, "Finalize"},
@@ -183,6 +183,8 @@ private:
         case DeviceState::TagRemoved:
             device_state = DeviceState::Initialized;
             break;
+        default:
+            break;
         }
         IPC::ResponseBuilder rb{ctx, 2};
         rb.Push(RESULT_SUCCESS);
@@ -324,7 +326,6 @@ private:
     Kernel::EventPair deactivate_event;
     Kernel::EventPair availability_change_event;
     const Module::Interface& nfp_interface;
-    Core::System& system;
 };
 
 void Module::Interface::CreateUserInterface(Kernel::HLERequestContext& ctx) {

src/core/hle/service/nifm/nifm.cpp

@@ -12,6 +12,13 @@
 
 namespace Service::NIFM {
 
+enum class RequestState : u32 {
+    NotSubmitted = 1,
+    Error = 1, ///< The duplicate 1 is intentional; it means both not submitted and error on HW.
+    Pending = 2,
+    Connected = 3,
+};
+
 class IScanRequest final : public ServiceFramework<IScanRequest> {
 public:
     explicit IScanRequest() : ServiceFramework("IScanRequest") {
@@ -81,7 +88,7 @@ private:
 
         IPC::ResponseBuilder rb{ctx, 3};
         rb.Push(RESULT_SUCCESS);
-        rb.Push<u32>(0);
+        rb.PushEnum(RequestState::Connected);
     }
 
     void GetResult(Kernel::HLERequestContext& ctx) {
@@ -189,14 +196,14 @@ private:
 
         IPC::ResponseBuilder rb{ctx, 3};
         rb.Push(RESULT_SUCCESS);
-        rb.Push<u8>(0);
+        rb.Push<u8>(1);
     }
     void IsAnyInternetRequestAccepted(Kernel::HLERequestContext& ctx) {
         LOG_WARNING(Service_NIFM, "(STUBBED) called");
 
         IPC::ResponseBuilder rb{ctx, 3};
         rb.Push(RESULT_SUCCESS);
-        rb.Push<u8>(0);
+        rb.Push<u8>(1);
     }
     Core::System& system;
 };

src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp

@@ -45,6 +45,8 @@ u32 nvhost_as_gpu::ioctl(Ioctl command, const std::vector<u8>& input, const std:
         return GetVARegions(input, output);
     case IoctlCommand::IocUnmapBufferCommand:
         return UnmapBuffer(input, output);
+    default:
+        break;
     }
 
     if (static_cast<IoctlCommand>(command.cmd.Value()) == IoctlCommand::IocRemapCommand)

src/core/hle/service/nvdrv/devices/nvhost_ctrl.cpp

@@ -38,9 +38,10 @@ u32 nvhost_ctrl::ioctl(Ioctl command, const std::vector<u8>& input, const std::v
         return IocCtrlEventUnregister(input, output);
     case IoctlCommand::IocCtrlEventSignalCommand:
         return IocCtrlEventSignal(input, output);
+    default:
+        UNIMPLEMENTED_MSG("Unimplemented ioctl");
+        return 0;
     }
-    UNIMPLEMENTED_MSG("Unimplemented ioctl");
-    return 0;
 }
 
 u32 nvhost_ctrl::NvOsGetConfigU32(const std::vector<u8>& input, std::vector<u8>& output) {

src/core/hle/service/nvdrv/devices/nvhost_ctrl_gpu.cpp

@@ -40,9 +40,10 @@ u32 nvhost_ctrl_gpu::ioctl(Ioctl command, const std::vector<u8>& input,
         return FlushL2(input, output);
     case IoctlCommand::IocGetGpuTime:
         return GetGpuTime(input, output);
+    default:
+        UNIMPLEMENTED_MSG("Unimplemented ioctl");
+        return 0;
     }
-    UNIMPLEMENTED_MSG("Unimplemented ioctl");
-    return 0;
 }
 
 u32 nvhost_ctrl_gpu::GetCharacteristics(const std::vector<u8>& input, std::vector<u8>& output,

src/core/hle/service/nvdrv/devices/nvhost_gpu.cpp

@@ -44,6 +44,8 @@ u32 nvhost_gpu::ioctl(Ioctl command, const std::vector<u8>& input, const std::ve
         return GetWaitbase(input, output);
     case IoctlCommand::IocChannelSetTimeoutCommand:
         return ChannelSetTimeout(input, output);
+    default:
+        break;
     }
 
     if (command.group == NVGPU_IOCTL_MAGIC) {

src/core/hle/service/service.cpp

@@ -208,7 +208,7 @@ void Init(std::shared_ptr<SM::ServiceManager>& sm, Core::System& system) {
     AOC::InstallInterfaces(*sm, system);
     APM::InstallInterfaces(system);
     Audio::InstallInterfaces(*sm, system);
-    BCAT::InstallInterfaces(*sm);
+    BCAT::InstallInterfaces(system);
     BPC::InstallInterfaces(*sm);
     BtDrv::InstallInterfaces(*sm, system);
     BTM::InstallInterfaces(*sm, system);

src/core/loader/nso.cpp

@@ -150,6 +150,7 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(Kernel::Process& process,
     // Apply cheats if they exist and the program has a valid title ID
     if (pm) {
         auto& system = Core::System::GetInstance();
+        system.SetCurrentProcessBuildID(nso_header.build_id);
         const auto cheats = pm->CreateCheatList(system, nso_header.build_id);
         if (!cheats.empty()) {
             system.RegisterCheatList(cheats, nso_header.build_id, load_base, image_size);

src/core/settings.cpp

@@ -103,6 +103,8 @@ void LogSettings() {
     LogSetting("Debugging_UseGdbstub", Settings::values.use_gdbstub);
     LogSetting("Debugging_GdbstubPort", Settings::values.gdbstub_port);
     LogSetting("Debugging_ProgramArgs", Settings::values.program_args);
+    LogSetting("Services_BCATBackend", Settings::values.bcat_backend);
+    LogSetting("Services_BCATBoxcatLocal", Settings::values.bcat_boxcat_local);
 }
 
 } // namespace Settings

src/core/settings.h

@@ -448,6 +448,10 @@ struct Values {
     bool reporting_services;
     bool quest_flag;
 
+    // BCAT
+    std::string bcat_backend;
+    bool bcat_boxcat_local;
+
     // WebService
     bool enable_telemetry;
     std::string web_api_url;

src/video_core/CMakeLists.txt

@@ -105,9 +105,15 @@ add_library(video_core STATIC
     shader/decode/warp.cpp
     shader/decode/xmad.cpp
     shader/decode/other.cpp
+    shader/ast.cpp
+    shader/ast.h
     shader/control_flow.cpp
     shader/control_flow.h
+    shader/compiler_settings.cpp
+    shader/compiler_settings.h
     shader/decode.cpp
+    shader/expr.cpp
+    shader/expr.h
     shader/node_helper.cpp
     shader/node_helper.h
     shader/node.h

src/video_core/renderer_opengl/gl_shader_decompiler.cpp

@@ -19,6 +19,7 @@
 #include "video_core/renderer_opengl/gl_device.h"
 #include "video_core/renderer_opengl/gl_rasterizer.h"
 #include "video_core/renderer_opengl/gl_shader_decompiler.h"
+#include "video_core/shader/ast.h"
 #include "video_core/shader/node.h"
 #include "video_core/shader/shader_ir.h"
 
@@ -334,39 +335,24 @@ constexpr bool IsVertexShader(ProgramType stage) {
     return stage == ProgramType::VertexA || stage == ProgramType::VertexB;
 }
 
+class ASTDecompiler;
+class ExprDecompiler;
+
 class GLSLDecompiler final {
 public:
     explicit GLSLDecompiler(const Device& device, const ShaderIR& ir, ProgramType stage,
                             std::string suffix)
         : device{device}, ir{ir}, stage{stage}, suffix{suffix}, header{ir.GetHeader()} {}
 
-    void Decompile() {
-        DeclareVertex();
-        DeclareGeometry();
-        DeclareRegisters();
-        DeclarePredicates();
-        DeclareLocalMemory();
-        DeclareSharedMemory();
-        DeclareInternalFlags();
-        DeclareInputAttributes();
-        DeclareOutputAttributes();
-        DeclareConstantBuffers();
-        DeclareGlobalMemory();
-        DeclareSamplers();
-        DeclarePhysicalAttributeReader();
-        DeclareImages();
-
-        code.AddLine("void execute_{}() {{", suffix);
-        ++code.scope;
-
+    void DecompileBranchMode() {
         // VM's program counter
         const auto first_address = ir.GetBasicBlocks().begin()->first;
         code.AddLine("uint jmp_to = {}U;", first_address);
 
         // TODO(Subv): Figure out the actual depth of the flow stack, for now it seems
         // unlikely that shaders will use 20 nested SSYs and PBKs.
+        constexpr u32 FLOW_STACK_SIZE = 20;
         if (!ir.IsFlowStackDisabled()) {
-            constexpr u32 FLOW_STACK_SIZE = 20;
             for (const auto stack : std::array{MetaStackClass::Ssy, MetaStackClass::Pbk}) {
                 code.AddLine("uint {}[{}];", FlowStackName(stack), FLOW_STACK_SIZE);
                 code.AddLine("uint {} = 0U;", FlowStackTopName(stack));
@@ -392,10 +378,37 @@ public:
         code.AddLine("default: return;");
         code.AddLine("}}");
 
-        for (std::size_t i = 0; i < 2; ++i) {
-            --code.scope;
-            code.AddLine("}}");
+        --code.scope;
+        code.AddLine("}}");
+    }
+
+    void DecompileAST();
+
+    void Decompile() {
+        DeclareVertex();
+        DeclareGeometry();
+        DeclareRegisters();
+        DeclarePredicates();
+        DeclareLocalMemory();
+        DeclareInternalFlags();
+        DeclareInputAttributes();
+        DeclareOutputAttributes();
+        DeclareConstantBuffers();
+        DeclareGlobalMemory();
+        DeclareSamplers();
+        DeclarePhysicalAttributeReader();
+
+        code.AddLine("void execute_{}() {{", suffix);
+        ++code.scope;
+
+        if (ir.IsDecompiled()) {
+            DecompileAST();
+        } else {
+            DecompileBranchMode();
         }
+
+        --code.scope;
+        code.AddLine("}}");
     }
 
     std::string GetResult() {
@@ -424,6 +437,9 @@ public:
     }
 
 private:
+    friend class ASTDecompiler;
+    friend class ExprDecompiler;
+
     void DeclareVertex() {
         if (!IsVertexShader(stage))
             return;
@@ -1821,10 +1837,9 @@ private:
         return {};
     }
 
-    Expression Exit(Operation operation) {
+    void PreExit() {
         if (stage != ProgramType::Fragment) {
-            code.AddLine("return;");
-            return {};
+            return;
         }
         const auto& used_registers = ir.GetRegisters();
         const auto SafeGetRegister = [&](u32 reg) -> Expression {
@@ -1856,7 +1871,10 @@ private:
             // already contains one past the last color register.
             code.AddLine("gl_FragDepth = {};", SafeGetRegister(current_reg + 1).AsFloat());
         }
+    }
 
+    Expression Exit(Operation operation) {
+        PreExit();
         code.AddLine("return;");
         return {};
     }
@@ -2253,6 +2271,208 @@ private:
     ShaderWriter code;
 };
 
+static constexpr std::string_view flow_var = "flow_var_";
+
+std::string GetFlowVariable(u32 i) {
+    return fmt::format("{}{}", flow_var, i);
+}
+
+class ExprDecompiler {
+public:
+    explicit ExprDecompiler(GLSLDecompiler& decomp) : decomp{decomp} {}
+
+    void operator()(VideoCommon::Shader::ExprAnd& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " && ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(VideoCommon::Shader::ExprOr& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " || ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(VideoCommon::Shader::ExprNot& expr) {
+        inner += '!';
+        std::visit(*this, *expr.operand1);
+    }
+
+    void operator()(VideoCommon::Shader::ExprPredicate& expr) {
+        const auto pred = static_cast<Tegra::Shader::Pred>(expr.predicate);
+        inner += decomp.GetPredicate(pred);
+    }
+
+    void operator()(VideoCommon::Shader::ExprCondCode& expr) {
+        const Node cc = decomp.ir.GetConditionCode(expr.cc);
+        std::string target;
+
+        if (const auto pred = std::get_if<PredicateNode>(&*cc)) {
+            const auto index = pred->GetIndex();
+            switch (index) {
+            case Tegra::Shader::Pred::NeverExecute:
+                target = "false";
+            case Tegra::Shader::Pred::UnusedIndex:
+                target = "true";
+            default:
+                target = decomp.GetPredicate(index);
+            }
+        } else if (const auto flag = std::get_if<InternalFlagNode>(&*cc)) {
+            target = decomp.GetInternalFlag(flag->GetFlag());
+        } else {
+            UNREACHABLE();
+        }
+        inner += target;
+    }
+
+    void operator()(VideoCommon::Shader::ExprVar& expr) {
+        inner += GetFlowVariable(expr.var_index);
+    }
+
+    void operator()(VideoCommon::Shader::ExprBoolean& expr) {
+        inner += expr.value ? "true" : "false";
+    }
+
+    std::string& GetResult() {
+        return inner;
+    }
+
+private:
+    std::string inner;
+    GLSLDecompiler& decomp;
+};
+
+class ASTDecompiler {
+public:
+    explicit ASTDecompiler(GLSLDecompiler& decomp) : decomp{decomp} {}
+
+    void operator()(VideoCommon::Shader::ASTProgram& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(VideoCommon::Shader::ASTIfThen& ast) {
+        ExprDecompiler expr_parser{decomp};
+        std::visit(expr_parser, *ast.condition);
+        decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
+        decomp.code.scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        decomp.code.scope--;
+        decomp.code.AddLine("}}");
+    }
+
+    void operator()(VideoCommon::Shader::ASTIfElse& ast) {
+        decomp.code.AddLine("else {{");
+        decomp.code.scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        decomp.code.scope--;
+        decomp.code.AddLine("}}");
+    }
+
+    void operator()(VideoCommon::Shader::ASTBlockEncoded& ast) {
+        UNREACHABLE();
+    }
+
+    void operator()(VideoCommon::Shader::ASTBlockDecoded& ast) {
+        decomp.VisitBlock(ast.nodes);
+    }
+
+    void operator()(VideoCommon::Shader::ASTVarSet& ast) {
+        ExprDecompiler expr_parser{decomp};
+        std::visit(expr_parser, *ast.condition);
+        decomp.code.AddLine("{} = {};", GetFlowVariable(ast.index), expr_parser.GetResult());
+    }
+
+    void operator()(VideoCommon::Shader::ASTLabel& ast) {
+        decomp.code.AddLine("// Label_{}:", ast.index);
+    }
+
+    void operator()(VideoCommon::Shader::ASTGoto& ast) {
+        UNREACHABLE();
+    }
+
+    void operator()(VideoCommon::Shader::ASTDoWhile& ast) {
+        ExprDecompiler expr_parser{decomp};
+        std::visit(expr_parser, *ast.condition);
+        decomp.code.AddLine("do {{");
+        decomp.code.scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        decomp.code.scope--;
+        decomp.code.AddLine("}} while({});", expr_parser.GetResult());
+    }
+
+    void operator()(VideoCommon::Shader::ASTReturn& ast) {
+        const bool is_true = VideoCommon::Shader::ExprIsTrue(ast.condition);
+        if (!is_true) {
+            ExprDecompiler expr_parser{decomp};
+            std::visit(expr_parser, *ast.condition);
+            decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
+            decomp.code.scope++;
+        }
+        if (ast.kills) {
+            decomp.code.AddLine("discard;");
+        } else {
+            decomp.PreExit();
+            decomp.code.AddLine("return;");
+        }
+        if (!is_true) {
+            decomp.code.scope--;
+            decomp.code.AddLine("}}");
+        }
+    }
+
+    void operator()(VideoCommon::Shader::ASTBreak& ast) {
+        const bool is_true = VideoCommon::Shader::ExprIsTrue(ast.condition);
+        if (!is_true) {
+            ExprDecompiler expr_parser{decomp};
+            std::visit(expr_parser, *ast.condition);
+            decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
+            decomp.code.scope++;
+        }
+        decomp.code.AddLine("break;");
+        if (!is_true) {
+            decomp.code.scope--;
+            decomp.code.AddLine("}}");
+        }
+    }
+
+    void Visit(VideoCommon::Shader::ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+    }
+
+private:
+    GLSLDecompiler& decomp;
+};
+
+void GLSLDecompiler::DecompileAST() {
+    const u32 num_flow_variables = ir.GetASTNumVariables();
+    for (u32 i = 0; i < num_flow_variables; i++) {
+        code.AddLine("bool {} = false;", GetFlowVariable(i));
+    }
+    ASTDecompiler decompiler{*this};
+    VideoCommon::Shader::ASTNode program = ir.GetASTProgram();
+    decompiler.Visit(program);
+}
+
 } // Anonymous namespace
 
 std::string GetCommonDeclarations() {

src/video_core/renderer_opengl/gl_shader_gen.cpp

@@ -11,12 +11,16 @@
 namespace OpenGL::GLShader {
 
 using Tegra::Engines::Maxwell3D;
+using VideoCommon::Shader::CompileDepth;
+using VideoCommon::Shader::CompilerSettings;
 using VideoCommon::Shader::ProgramCode;
 using VideoCommon::Shader::ShaderIR;
 
 static constexpr u32 PROGRAM_OFFSET = 10;
 static constexpr u32 COMPUTE_OFFSET = 0;
 
+static constexpr CompilerSettings settings{CompileDepth::NoFlowStack, true};
+
 ProgramResult GenerateVertexShader(const Device& device, const ShaderSetup& setup) {
     const std::string id = fmt::format("{:016x}", setup.program.unique_identifier);
 
@@ -31,13 +35,14 @@ layout (std140, binding = EMULATION_UBO_BINDING) uniform vs_config {
 
 )";
 
-    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a);
+    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a, settings);
     const auto stage = setup.IsDualProgram() ? ProgramType::VertexA : ProgramType::VertexB;
     ProgramResult program = Decompile(device, program_ir, stage, "vertex");
     out += program.first;
 
     if (setup.IsDualProgram()) {
-        const ShaderIR program_ir_b(setup.program.code_b, PROGRAM_OFFSET, setup.program.size_b);
+        const ShaderIR program_ir_b(setup.program.code_b, PROGRAM_OFFSET, setup.program.size_b,
+                                    settings);
         ProgramResult program_b = Decompile(device, program_ir_b, ProgramType::VertexB, "vertex_b");
         out += program_b.first;
     }
@@ -80,7 +85,7 @@ layout (std140, binding = EMULATION_UBO_BINDING) uniform gs_config {
 
 )";
 
-    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a);
+    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a, settings);
     ProgramResult program = Decompile(device, program_ir, ProgramType::Geometry, "geometry");
     out += program.first;
 
@@ -114,7 +119,8 @@ layout (std140, binding = EMULATION_UBO_BINDING) uniform fs_config {
 };
 
 )";
-    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a);
+
+    const ShaderIR program_ir(setup.program.code, PROGRAM_OFFSET, setup.program.size_a, settings);
     ProgramResult program = Decompile(device, program_ir, ProgramType::Fragment, "fragment");
     out += program.first;
 
@@ -133,7 +139,7 @@ ProgramResult GenerateComputeShader(const Device& device, const ShaderSetup& set
     std::string out = "// Shader Unique Id: CS" + id + "\n\n";
     out += GetCommonDeclarations();
 
-    const ShaderIR program_ir(setup.program.code, COMPUTE_OFFSET, setup.program.size_a);
+    const ShaderIR program_ir(setup.program.code, COMPUTE_OFFSET, setup.program.size_a, settings);
     ProgramResult program = Decompile(device, program_ir, ProgramType::Compute, "compute");
     out += program.first;
 

src/video_core/renderer_vulkan/vk_shader_decompiler.cpp

@@ -88,6 +88,9 @@ bool IsPrecise(Operation operand) {
 
 } // namespace
 
+class ASTDecompiler;
+class ExprDecompiler;
+
 class SPIRVDecompiler : public Sirit::Module {
 public:
     explicit SPIRVDecompiler(const VKDevice& device, const ShaderIR& ir, ShaderStage stage)
@@ -97,27 +100,7 @@ public:
         AddExtension("SPV_KHR_variable_pointers");
     }
 
-    void Decompile() {
-        AllocateBindings();
-        AllocateLabels();
-
-        DeclareVertex();
-        DeclareGeometry();
-        DeclareFragment();
-        DeclareRegisters();
-        DeclarePredicates();
-        DeclareLocalMemory();
-        DeclareInternalFlags();
-        DeclareInputAttributes();
-        DeclareOutputAttributes();
-        DeclareConstantBuffers();
-        DeclareGlobalBuffers();
-        DeclareSamplers();
-
-        execute_function =
-            Emit(OpFunction(t_void, spv::FunctionControlMask::Inline, TypeFunction(t_void)));
-        Emit(OpLabel());
-
+    void DecompileBranchMode() {
         const u32 first_address = ir.GetBasicBlocks().begin()->first;
         const Id loop_label = OpLabel("loop");
         const Id merge_label = OpLabel("merge");
@@ -174,6 +157,43 @@ public:
         Emit(continue_label);
         Emit(OpBranch(loop_label));
         Emit(merge_label);
+    }
+
+    void DecompileAST();
+
+    void Decompile() {
+        const bool is_fully_decompiled = ir.IsDecompiled();
+        AllocateBindings();
+        if (!is_fully_decompiled) {
+            AllocateLabels();
+        }
+
+        DeclareVertex();
+        DeclareGeometry();
+        DeclareFragment();
+        DeclareRegisters();
+        DeclarePredicates();
+        if (is_fully_decompiled) {
+            DeclareFlowVariables();
+        }
+        DeclareLocalMemory();
+        DeclareInternalFlags();
+        DeclareInputAttributes();
+        DeclareOutputAttributes();
+        DeclareConstantBuffers();
+        DeclareGlobalBuffers();
+        DeclareSamplers();
+
+        execute_function =
+            Emit(OpFunction(t_void, spv::FunctionControlMask::Inline, TypeFunction(t_void)));
+        Emit(OpLabel());
+
+        if (is_fully_decompiled) {
+            DecompileAST();
+        } else {
+            DecompileBranchMode();
+        }
+
         Emit(OpReturn());
         Emit(OpFunctionEnd());
     }
@@ -206,6 +226,9 @@ public:
     }
 
 private:
+    friend class ASTDecompiler;
+    friend class ExprDecompiler;
+
     static constexpr auto INTERNAL_FLAGS_COUNT = static_cast<std::size_t>(InternalFlag::Amount);
 
     void AllocateBindings() {
@@ -294,6 +317,14 @@ private:
         }
     }
 
+    void DeclareFlowVariables() {
+        for (u32 i = 0; i < ir.GetASTNumVariables(); i++) {
+            const Id id = OpVariable(t_prv_bool, spv::StorageClass::Private, v_false);
+            Name(id, fmt::format("flow_var_{}", static_cast<u32>(i)));
+            flow_variables.emplace(i, AddGlobalVariable(id));
+        }
+    }
+
     void DeclareLocalMemory() {
         if (const u64 local_memory_size = header.GetLocalMemorySize(); local_memory_size > 0) {
             const auto element_count = static_cast<u32>(Common::AlignUp(local_memory_size, 4) / 4);
@@ -615,9 +646,15 @@ private:
             Emit(OpBranchConditional(condition, true_label, skip_label));
             Emit(true_label);
 
+            ++conditional_nest_count;
             VisitBasicBlock(conditional->GetCode());
+            --conditional_nest_count;
 
-            Emit(OpBranch(skip_label));
+            if (inside_branch == 0) {
+                Emit(OpBranch(skip_label));
+            } else {
+                inside_branch--;
+            }
             Emit(skip_label);
             return {};
 
@@ -980,7 +1017,11 @@ private:
         UNIMPLEMENTED_IF(!target);
 
         Emit(OpStore(jmp_to, Constant(t_uint, target->GetValue())));
-        BranchingOp([&]() { Emit(OpBranch(continue_label)); });
+        Emit(OpBranch(continue_label));
+        inside_branch = conditional_nest_count;
+        if (conditional_nest_count == 0) {
+            Emit(OpLabel());
+        }
         return {};
     }
 
@@ -988,7 +1029,11 @@ private:
         const Id op_a = VisitOperand<Type::Uint>(operation, 0);
 
         Emit(OpStore(jmp_to, op_a));
-        BranchingOp([&]() { Emit(OpBranch(continue_label)); });
+        Emit(OpBranch(continue_label));
+        inside_branch = conditional_nest_count;
+        if (conditional_nest_count == 0) {
+            Emit(OpLabel());
+        }
         return {};
     }
 
@@ -1015,11 +1060,15 @@ private:
 
         Emit(OpStore(flow_stack_top, previous));
         Emit(OpStore(jmp_to, target));
-        BranchingOp([&]() { Emit(OpBranch(continue_label)); });
+        Emit(OpBranch(continue_label));
+        inside_branch = conditional_nest_count;
+        if (conditional_nest_count == 0) {
+            Emit(OpLabel());
+        }
         return {};
     }
 
-    Id Exit(Operation operation) {
+    Id PreExit() {
         switch (stage) {
         case ShaderStage::Vertex: {
             // TODO(Rodrigo): We should use VK_EXT_depth_range_unrestricted instead, but it doesn't
@@ -1067,12 +1116,35 @@ private:
         }
         }
 
-        BranchingOp([&]() { Emit(OpReturn()); });
+        return {};
+    }
+
+    Id Exit(Operation operation) {
+        PreExit();
+        inside_branch = conditional_nest_count;
+        if (conditional_nest_count > 0) {
+            Emit(OpReturn());
+        } else {
+            const Id dummy = OpLabel();
+            Emit(OpBranch(dummy));
+            Emit(dummy);
+            Emit(OpReturn());
+            Emit(OpLabel());
+        }
         return {};
     }
 
     Id Discard(Operation operation) {
-        BranchingOp([&]() { Emit(OpKill()); });
+        inside_branch = conditional_nest_count;
+        if (conditional_nest_count > 0) {
+            Emit(OpKill());
+        } else {
+            const Id dummy = OpLabel();
+            Emit(OpBranch(dummy));
+            Emit(dummy);
+            Emit(OpKill());
+            Emit(OpLabel());
+        }
         return {};
     }
 
@@ -1267,17 +1339,6 @@ private:
         return {};
     }
 
-    void BranchingOp(std::function<void()> call) {
-        const Id true_label = OpLabel();
-        const Id skip_label = OpLabel();
-        Emit(OpSelectionMerge(skip_label, spv::SelectionControlMask::Flatten));
-        Emit(OpBranchConditional(v_true, true_label, skip_label, 1, 0));
-        Emit(true_label);
-        call();
-
-        Emit(skip_label);
-    }
-
     std::tuple<Id, Id> CreateFlowStack() {
         // TODO(Rodrigo): Figure out the actual depth of the flow stack, for now it seems unlikely
         // that shaders will use 20 nested SSYs and PBKs.
@@ -1483,6 +1544,8 @@ private:
     const ShaderIR& ir;
     const ShaderStage stage;
     const Tegra::Shader::Header header;
+    u64 conditional_nest_count{};
+    u64 inside_branch{};
 
     const Id t_void = Name(TypeVoid(), "void");
 
@@ -1545,6 +1608,7 @@ private:
     Id per_vertex{};
     std::map<u32, Id> registers;
     std::map<Tegra::Shader::Pred, Id> predicates;
+    std::map<u32, Id> flow_variables;
     Id local_memory{};
     std::array<Id, INTERNAL_FLAGS_COUNT> internal_flags{};
     std::map<Attribute::Index, Id> input_attributes;
@@ -1580,6 +1644,223 @@ private:
     std::map<u32, Id> labels;
 };
 
+class ExprDecompiler {
+public:
+    explicit ExprDecompiler(SPIRVDecompiler& decomp) : decomp{decomp} {}
+
+    Id operator()(VideoCommon::Shader::ExprAnd& expr) {
+        const Id type_def = decomp.GetTypeDefinition(Type::Bool);
+        const Id op1 = Visit(expr.operand1);
+        const Id op2 = Visit(expr.operand2);
+        return decomp.Emit(decomp.OpLogicalAnd(type_def, op1, op2));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprOr& expr) {
+        const Id type_def = decomp.GetTypeDefinition(Type::Bool);
+        const Id op1 = Visit(expr.operand1);
+        const Id op2 = Visit(expr.operand2);
+        return decomp.Emit(decomp.OpLogicalOr(type_def, op1, op2));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprNot& expr) {
+        const Id type_def = decomp.GetTypeDefinition(Type::Bool);
+        const Id op1 = Visit(expr.operand1);
+        return decomp.Emit(decomp.OpLogicalNot(type_def, op1));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprPredicate& expr) {
+        const auto pred = static_cast<Tegra::Shader::Pred>(expr.predicate);
+        return decomp.Emit(decomp.OpLoad(decomp.t_bool, decomp.predicates.at(pred)));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprCondCode& expr) {
+        const Node cc = decomp.ir.GetConditionCode(expr.cc);
+        Id target;
+
+        if (const auto pred = std::get_if<PredicateNode>(&*cc)) {
+            const auto index = pred->GetIndex();
+            switch (index) {
+            case Tegra::Shader::Pred::NeverExecute:
+                target = decomp.v_false;
+            case Tegra::Shader::Pred::UnusedIndex:
+                target = decomp.v_true;
+            default:
+                target = decomp.predicates.at(index);
+            }
+        } else if (const auto flag = std::get_if<InternalFlagNode>(&*cc)) {
+            target = decomp.internal_flags.at(static_cast<u32>(flag->GetFlag()));
+        }
+        return decomp.Emit(decomp.OpLoad(decomp.t_bool, target));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprVar& expr) {
+        return decomp.Emit(decomp.OpLoad(decomp.t_bool, decomp.flow_variables.at(expr.var_index)));
+    }
+
+    Id operator()(VideoCommon::Shader::ExprBoolean& expr) {
+        return expr.value ? decomp.v_true : decomp.v_false;
+    }
+
+    Id Visit(VideoCommon::Shader::Expr& node) {
+        return std::visit(*this, *node);
+    }
+
+private:
+    SPIRVDecompiler& decomp;
+};
+
+class ASTDecompiler {
+public:
+    explicit ASTDecompiler(SPIRVDecompiler& decomp) : decomp{decomp} {}
+
+    void operator()(VideoCommon::Shader::ASTProgram& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(VideoCommon::Shader::ASTIfThen& ast) {
+        ExprDecompiler expr_parser{decomp};
+        const Id condition = expr_parser.Visit(ast.condition);
+        const Id then_label = decomp.OpLabel();
+        const Id endif_label = decomp.OpLabel();
+        decomp.Emit(decomp.OpSelectionMerge(endif_label, spv::SelectionControlMask::MaskNone));
+        decomp.Emit(decomp.OpBranchConditional(condition, then_label, endif_label));
+        decomp.Emit(then_label);
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        decomp.Emit(decomp.OpBranch(endif_label));
+        decomp.Emit(endif_label);
+    }
+
+    void operator()(VideoCommon::Shader::ASTIfElse& ast) {
+        UNREACHABLE();
+    }
+
+    void operator()(VideoCommon::Shader::ASTBlockEncoded& ast) {
+        UNREACHABLE();
+    }
+
+    void operator()(VideoCommon::Shader::ASTBlockDecoded& ast) {
+        decomp.VisitBasicBlock(ast.nodes);
+    }
+
+    void operator()(VideoCommon::Shader::ASTVarSet& ast) {
+        ExprDecompiler expr_parser{decomp};
+        const Id condition = expr_parser.Visit(ast.condition);
+        decomp.Emit(decomp.OpStore(decomp.flow_variables.at(ast.index), condition));
+    }
+
+    void operator()(VideoCommon::Shader::ASTLabel& ast) {
+        // Do nothing
+    }
+
+    void operator()(VideoCommon::Shader::ASTGoto& ast) {
+        UNREACHABLE();
+    }
+
+    void operator()(VideoCommon::Shader::ASTDoWhile& ast) {
+        const Id loop_label = decomp.OpLabel();
+        const Id endloop_label = decomp.OpLabel();
+        const Id loop_start_block = decomp.OpLabel();
+        const Id loop_end_block = decomp.OpLabel();
+        current_loop_exit = endloop_label;
+        decomp.Emit(decomp.OpBranch(loop_label));
+        decomp.Emit(loop_label);
+        decomp.Emit(
+            decomp.OpLoopMerge(endloop_label, loop_end_block, spv::LoopControlMask::MaskNone));
+        decomp.Emit(decomp.OpBranch(loop_start_block));
+        decomp.Emit(loop_start_block);
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        ExprDecompiler expr_parser{decomp};
+        const Id condition = expr_parser.Visit(ast.condition);
+        decomp.Emit(decomp.OpBranchConditional(condition, loop_label, endloop_label));
+        decomp.Emit(endloop_label);
+    }
+
+    void operator()(VideoCommon::Shader::ASTReturn& ast) {
+        if (!VideoCommon::Shader::ExprIsTrue(ast.condition)) {
+            ExprDecompiler expr_parser{decomp};
+            const Id condition = expr_parser.Visit(ast.condition);
+            const Id then_label = decomp.OpLabel();
+            const Id endif_label = decomp.OpLabel();
+            decomp.Emit(decomp.OpSelectionMerge(endif_label, spv::SelectionControlMask::MaskNone));
+            decomp.Emit(decomp.OpBranchConditional(condition, then_label, endif_label));
+            decomp.Emit(then_label);
+            if (ast.kills) {
+                decomp.Emit(decomp.OpKill());
+            } else {
+                decomp.PreExit();
+                decomp.Emit(decomp.OpReturn());
+            }
+            decomp.Emit(endif_label);
+        } else {
+            const Id next_block = decomp.OpLabel();
+            decomp.Emit(decomp.OpBranch(next_block));
+            decomp.Emit(next_block);
+            if (ast.kills) {
+                decomp.Emit(decomp.OpKill());
+            } else {
+                decomp.PreExit();
+                decomp.Emit(decomp.OpReturn());
+            }
+            decomp.Emit(decomp.OpLabel());
+        }
+    }
+
+    void operator()(VideoCommon::Shader::ASTBreak& ast) {
+        if (!VideoCommon::Shader::ExprIsTrue(ast.condition)) {
+            ExprDecompiler expr_parser{decomp};
+            const Id condition = expr_parser.Visit(ast.condition);
+            const Id then_label = decomp.OpLabel();
+            const Id endif_label = decomp.OpLabel();
+            decomp.Emit(decomp.OpSelectionMerge(endif_label, spv::SelectionControlMask::MaskNone));
+            decomp.Emit(decomp.OpBranchConditional(condition, then_label, endif_label));
+            decomp.Emit(then_label);
+            decomp.Emit(decomp.OpBranch(current_loop_exit));
+            decomp.Emit(endif_label);
+        } else {
+            const Id next_block = decomp.OpLabel();
+            decomp.Emit(decomp.OpBranch(next_block));
+            decomp.Emit(next_block);
+            decomp.Emit(decomp.OpBranch(current_loop_exit));
+            decomp.Emit(decomp.OpLabel());
+        }
+    }
+
+    void Visit(VideoCommon::Shader::ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+    }
+
+private:
+    SPIRVDecompiler& decomp;
+    Id current_loop_exit{};
+};
+
+void SPIRVDecompiler::DecompileAST() {
+    const u32 num_flow_variables = ir.GetASTNumVariables();
+    for (u32 i = 0; i < num_flow_variables; i++) {
+        const Id id = OpVariable(t_prv_bool, spv::StorageClass::Private, v_false);
+        Name(id, fmt::format("flow_var_{}", i));
+        flow_variables.emplace(i, AddGlobalVariable(id));
+    }
+    ASTDecompiler decompiler{*this};
+    VideoCommon::Shader::ASTNode program = ir.GetASTProgram();
+    decompiler.Visit(program);
+    const Id next_block = OpLabel();
+    Emit(OpBranch(next_block));
+    Emit(next_block);
+}
+
 DecompilerResult Decompile(const VKDevice& device, const VideoCommon::Shader::ShaderIR& ir,
                            Maxwell::ShaderStage stage) {
     auto decompiler = std::make_unique<SPIRVDecompiler>(device, ir, stage);

src/video_core/shader/ast.cpp

@@ -0,0 +1,738 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <string>
+
+#include "common/assert.h"
+#include "common/common_types.h"
+#include "video_core/shader/ast.h"
+#include "video_core/shader/expr.h"
+
+namespace VideoCommon::Shader {
+
+ASTZipper::ASTZipper() = default;
+
+void ASTZipper::Init(const ASTNode new_first, const ASTNode parent) {
+    ASSERT(new_first->manager == nullptr);
+    first = new_first;
+    last = new_first;
+
+    ASTNode current = first;
+    while (current) {
+        current->manager = this;
+        current->parent = parent;
+        last = current;
+        current = current->next;
+    }
+}
+
+void ASTZipper::PushBack(const ASTNode new_node) {
+    ASSERT(new_node->manager == nullptr);
+    new_node->previous = last;
+    if (last) {
+        last->next = new_node;
+    }
+    new_node->next.reset();
+    last = new_node;
+    if (!first) {
+        first = new_node;
+    }
+    new_node->manager = this;
+}
+
+void ASTZipper::PushFront(const ASTNode new_node) {
+    ASSERT(new_node->manager == nullptr);
+    new_node->previous.reset();
+    new_node->next = first;
+    if (first) {
+        first->previous = new_node;
+    }
+    if (last == first) {
+        last = new_node;
+    }
+    first = new_node;
+    new_node->manager = this;
+}
+
+void ASTZipper::InsertAfter(const ASTNode new_node, const ASTNode at_node) {
+    ASSERT(new_node->manager == nullptr);
+    if (!at_node) {
+        PushFront(new_node);
+        return;
+    }
+    const ASTNode next = at_node->next;
+    if (next) {
+        next->previous = new_node;
+    }
+    new_node->previous = at_node;
+    if (at_node == last) {
+        last = new_node;
+    }
+    new_node->next = next;
+    at_node->next = new_node;
+    new_node->manager = this;
+}
+
+void ASTZipper::InsertBefore(const ASTNode new_node, const ASTNode at_node) {
+    ASSERT(new_node->manager == nullptr);
+    if (!at_node) {
+        PushBack(new_node);
+        return;
+    }
+    const ASTNode previous = at_node->previous;
+    if (previous) {
+        previous->next = new_node;
+    }
+    new_node->next = at_node;
+    if (at_node == first) {
+        first = new_node;
+    }
+    new_node->previous = previous;
+    at_node->previous = new_node;
+    new_node->manager = this;
+}
+
+void ASTZipper::DetachTail(ASTNode node) {
+    ASSERT(node->manager == this);
+    if (node == first) {
+        first.reset();
+        last.reset();
+        return;
+    }
+
+    last = node->previous;
+    last->next.reset();
+    node->previous.reset();
+
+    ASTNode current = std::move(node);
+    while (current) {
+        current->manager = nullptr;
+        current->parent.reset();
+        current = current->next;
+    }
+}
+
+void ASTZipper::DetachSegment(const ASTNode start, const ASTNode end) {
+    ASSERT(start->manager == this && end->manager == this);
+    if (start == end) {
+        DetachSingle(start);
+        return;
+    }
+    const ASTNode prev = start->previous;
+    const ASTNode post = end->next;
+    if (!prev) {
+        first = post;
+    } else {
+        prev->next = post;
+    }
+    if (!post) {
+        last = prev;
+    } else {
+        post->previous = prev;
+    }
+    start->previous.reset();
+    end->next.reset();
+    ASTNode current = start;
+    bool found = false;
+    while (current) {
+        current->manager = nullptr;
+        current->parent.reset();
+        found |= current == end;
+        current = current->next;
+    }
+    ASSERT(found);
+}
+
+void ASTZipper::DetachSingle(const ASTNode node) {
+    ASSERT(node->manager == this);
+    const ASTNode prev = node->previous;
+    const ASTNode post = node->next;
+    node->previous.reset();
+    node->next.reset();
+    if (!prev) {
+        first = post;
+    } else {
+        prev->next = post;
+    }
+    if (!post) {
+        last = prev;
+    } else {
+        post->previous = prev;
+    }
+
+    node->manager = nullptr;
+    node->parent.reset();
+}
+
+void ASTZipper::Remove(const ASTNode node) {
+    ASSERT(node->manager == this);
+    const ASTNode next = node->next;
+    const ASTNode previous = node->previous;
+    if (previous) {
+        previous->next = next;
+    }
+    if (next) {
+        next->previous = previous;
+    }
+    node->parent.reset();
+    node->manager = nullptr;
+    if (node == last) {
+        last = previous;
+    }
+    if (node == first) {
+        first = next;
+    }
+}
+
+class ExprPrinter final {
+public:
+    void operator()(const ExprAnd& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " && ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(const ExprOr& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " || ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(const ExprNot& expr) {
+        inner += "!";
+        std::visit(*this, *expr.operand1);
+    }
+
+    void operator()(const ExprPredicate& expr) {
+        inner += "P" + std::to_string(expr.predicate);
+    }
+
+    void operator()(const ExprCondCode& expr) {
+        u32 cc = static_cast<u32>(expr.cc);
+        inner += "CC" + std::to_string(cc);
+    }
+
+    void operator()(const ExprVar& expr) {
+        inner += "V" + std::to_string(expr.var_index);
+    }
+
+    void operator()(const ExprBoolean& expr) {
+        inner += expr.value ? "true" : "false";
+    }
+
+    const std::string& GetResult() const {
+        return inner;
+    }
+
+    std::string inner{};
+};
+
+class ASTPrinter {
+public:
+    void operator()(const ASTProgram& ast) {
+        scope++;
+        inner += "program {\n";
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        inner += "}\n";
+        scope--;
+    }
+
+    void operator()(const ASTIfThen& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "if (" + expr_parser.GetResult() + ") {\n";
+        scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        scope--;
+        inner += Ident() + "}\n";
+    }
+
+    void operator()(const ASTIfElse& ast) {
+        inner += Ident() + "else {\n";
+        scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        scope--;
+        inner += Ident() + "}\n";
+    }
+
+    void operator()(const ASTBlockEncoded& ast) {
+        inner += Ident() + "Block(" + std::to_string(ast.start) + ", " + std::to_string(ast.end) +
+                 ");\n";
+    }
+
+    void operator()(const ASTBlockDecoded& ast) {
+        inner += Ident() + "Block;\n";
+    }
+
+    void operator()(const ASTVarSet& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner +=
+            Ident() + "V" + std::to_string(ast.index) + " := " + expr_parser.GetResult() + ";\n";
+    }
+
+    void operator()(const ASTLabel& ast) {
+        inner += "Label_" + std::to_string(ast.index) + ":\n";
+    }
+
+    void operator()(const ASTGoto& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "(" + expr_parser.GetResult() + ") -> goto Label_" +
+                 std::to_string(ast.label) + ";\n";
+    }
+
+    void operator()(const ASTDoWhile& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "do {\n";
+        scope++;
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+        scope--;
+        inner += Ident() + "} while (" + expr_parser.GetResult() + ");\n";
+    }
+
+    void operator()(const ASTReturn& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "(" + expr_parser.GetResult() + ") -> " +
+                 (ast.kills ? "discard" : "exit") + ";\n";
+    }
+
+    void operator()(const ASTBreak& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "(" + expr_parser.GetResult() + ") -> break;\n";
+    }
+
+    std::string& Ident() {
+        if (memo_scope == scope) {
+            return tabs_memo;
+        }
+        tabs_memo = tabs.substr(0, scope * 2);
+        memo_scope = scope;
+        return tabs_memo;
+    }
+
+    void Visit(ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+    }
+
+    const std::string& GetResult() const {
+        return inner;
+    }
+
+private:
+    std::string inner{};
+    u32 scope{};
+
+    std::string tabs_memo{};
+    u32 memo_scope{};
+
+    static constexpr std::string_view tabs{"                                    "};
+};
+
+std::string ASTManager::Print() {
+    ASTPrinter printer{};
+    printer.Visit(main_node);
+    return printer.GetResult();
+}
+
+ASTManager::ASTManager(bool full_decompile, bool disable_else_derivation)
+    : full_decompile{full_decompile}, disable_else_derivation{disable_else_derivation} {};
+
+ASTManager::~ASTManager() {
+    Clear();
+}
+
+void ASTManager::Init() {
+    main_node = ASTBase::Make<ASTProgram>(ASTNode{});
+    program = std::get_if<ASTProgram>(main_node->GetInnerData());
+    false_condition = MakeExpr<ExprBoolean>(false);
+}
+
+void ASTManager::DeclareLabel(u32 address) {
+    const auto pair = labels_map.emplace(address, labels_count);
+    if (pair.second) {
+        labels_count++;
+        labels.resize(labels_count);
+    }
+}
+
+void ASTManager::InsertLabel(u32 address) {
+    const u32 index = labels_map[address];
+    const ASTNode label = ASTBase::Make<ASTLabel>(main_node, index);
+    labels[index] = label;
+    program->nodes.PushBack(label);
+}
+
+void ASTManager::InsertGoto(Expr condition, u32 address) {
+    const u32 index = labels_map[address];
+    const ASTNode goto_node = ASTBase::Make<ASTGoto>(main_node, std::move(condition), index);
+    gotos.push_back(goto_node);
+    program->nodes.PushBack(goto_node);
+}
+
+void ASTManager::InsertBlock(u32 start_address, u32 end_address) {
+    ASTNode block = ASTBase::Make<ASTBlockEncoded>(main_node, start_address, end_address);
+    program->nodes.PushBack(std::move(block));
+}
+
+void ASTManager::InsertReturn(Expr condition, bool kills) {
+    ASTNode node = ASTBase::Make<ASTReturn>(main_node, std::move(condition), kills);
+    program->nodes.PushBack(std::move(node));
+}
+
+// The decompile algorithm is based on
+// "Taming control flow: A structured approach to eliminating goto statements"
+// by AM Erosa, LJ Hendren 1994. In general, the idea is to get gotos to be
+// on the same structured level as the label which they jump to. This is done,
+// through outward/inward movements and lifting. Once they are at the same
+// level, you can enclose them in an "if" structure or a "do-while" structure.
+void ASTManager::Decompile() {
+    auto it = gotos.begin();
+    while (it != gotos.end()) {
+        const ASTNode goto_node = *it;
+        const auto label_index = goto_node->GetGotoLabel();
+        if (!label_index) {
+            return;
+        }
+        const ASTNode label = labels[*label_index];
+        if (!full_decompile) {
+            // We only decompile backward jumps
+            if (!IsBackwardsJump(goto_node, label)) {
+                it++;
+                continue;
+            }
+        }
+        if (IndirectlyRelated(goto_node, label)) {
+            while (!DirectlyRelated(goto_node, label)) {
+                MoveOutward(goto_node);
+            }
+        }
+        if (DirectlyRelated(goto_node, label)) {
+            u32 goto_level = goto_node->GetLevel();
+            const u32 label_level = label->GetLevel();
+            while (label_level < goto_level) {
+                MoveOutward(goto_node);
+                goto_level--;
+            }
+            // TODO(Blinkhawk): Implement Lifting and Inward Movements
+        }
+        if (label->GetParent() == goto_node->GetParent()) {
+            bool is_loop = false;
+            ASTNode current = goto_node->GetPrevious();
+            while (current) {
+                if (current == label) {
+                    is_loop = true;
+                    break;
+                }
+                current = current->GetPrevious();
+            }
+
+            if (is_loop) {
+                EncloseDoWhile(goto_node, label);
+            } else {
+                EncloseIfThen(goto_node, label);
+            }
+            it = gotos.erase(it);
+            continue;
+        }
+        it++;
+    }
+    if (full_decompile) {
+        for (const ASTNode& label : labels) {
+            auto& manager = label->GetManager();
+            manager.Remove(label);
+        }
+        labels.clear();
+    } else {
+        auto label_it = labels.begin();
+        while (label_it != labels.end()) {
+            bool can_remove = true;
+            ASTNode label = *label_it;
+            for (const ASTNode& goto_node : gotos) {
+                const auto label_index = goto_node->GetGotoLabel();
+                if (!label_index) {
+                    return;
+                }
+                ASTNode& glabel = labels[*label_index];
+                if (glabel == label) {
+                    can_remove = false;
+                    break;
+                }
+            }
+            if (can_remove) {
+                label->MarkLabelUnused();
+            }
+        }
+    }
+}
+
+bool ASTManager::IsBackwardsJump(ASTNode goto_node, ASTNode label_node) const {
+    u32 goto_level = goto_node->GetLevel();
+    u32 label_level = label_node->GetLevel();
+    while (goto_level > label_level) {
+        goto_level--;
+        goto_node = goto_node->GetParent();
+    }
+    while (label_level > goto_level) {
+        label_level--;
+        label_node = label_node->GetParent();
+    }
+    while (goto_node->GetParent() != label_node->GetParent()) {
+        goto_node = goto_node->GetParent();
+        label_node = label_node->GetParent();
+    }
+    ASTNode current = goto_node->GetPrevious();
+    while (current) {
+        if (current == label_node) {
+            return true;
+        }
+        current = current->GetPrevious();
+    }
+    return false;
+}
+
+bool ASTManager::IndirectlyRelated(const ASTNode& first, const ASTNode& second) const {
+    return !(first->GetParent() == second->GetParent() || DirectlyRelated(first, second));
+}
+
+bool ASTManager::DirectlyRelated(const ASTNode& first, const ASTNode& second) const {
+    if (first->GetParent() == second->GetParent()) {
+        return false;
+    }
+    const u32 first_level = first->GetLevel();
+    const u32 second_level = second->GetLevel();
+    u32 min_level;
+    u32 max_level;
+    ASTNode max;
+    ASTNode min;
+    if (first_level > second_level) {
+        min_level = second_level;
+        min = second;
+        max_level = first_level;
+        max = first;
+    } else {
+        min_level = first_level;
+        min = first;
+        max_level = second_level;
+        max = second;
+    }
+
+    while (max_level > min_level) {
+        max_level--;
+        max = max->GetParent();
+    }
+
+    return min->GetParent() == max->GetParent();
+}
+
+void ASTManager::ShowCurrentState(std::string_view state) {
+    LOG_CRITICAL(HW_GPU, "\nState {}:\n\n{}\n", state, Print());
+    SanityCheck();
+}
+
+void ASTManager::SanityCheck() {
+    for (auto& label : labels) {
+        if (!label->GetParent()) {
+            LOG_CRITICAL(HW_GPU, "Sanity Check Failed");
+        }
+    }
+}
+
+void ASTManager::EncloseDoWhile(ASTNode goto_node, ASTNode label) {
+    ASTZipper& zipper = goto_node->GetManager();
+    const ASTNode loop_start = label->GetNext();
+    if (loop_start == goto_node) {
+        zipper.Remove(goto_node);
+        return;
+    }
+    const ASTNode parent = label->GetParent();
+    const Expr condition = goto_node->GetGotoCondition();
+    zipper.DetachSegment(loop_start, goto_node);
+    const ASTNode do_while_node = ASTBase::Make<ASTDoWhile>(parent, condition);
+    ASTZipper* sub_zipper = do_while_node->GetSubNodes();
+    sub_zipper->Init(loop_start, do_while_node);
+    zipper.InsertAfter(do_while_node, label);
+    sub_zipper->Remove(goto_node);
+}
+
+void ASTManager::EncloseIfThen(ASTNode goto_node, ASTNode label) {
+    ASTZipper& zipper = goto_node->GetManager();
+    const ASTNode if_end = label->GetPrevious();
+    if (if_end == goto_node) {
+        zipper.Remove(goto_node);
+        return;
+    }
+    const ASTNode prev = goto_node->GetPrevious();
+    const Expr condition = goto_node->GetGotoCondition();
+    bool do_else = false;
+    if (!disable_else_derivation && prev->IsIfThen()) {
+        const Expr if_condition = prev->GetIfCondition();
+        do_else = ExprAreEqual(if_condition, condition);
+    }
+    const ASTNode parent = label->GetParent();
+    zipper.DetachSegment(goto_node, if_end);
+    ASTNode if_node;
+    if (do_else) {
+        if_node = ASTBase::Make<ASTIfElse>(parent);
+    } else {
+        Expr neg_condition = MakeExprNot(condition);
+        if_node = ASTBase::Make<ASTIfThen>(parent, neg_condition);
+    }
+    ASTZipper* sub_zipper = if_node->GetSubNodes();
+    sub_zipper->Init(goto_node, if_node);
+    zipper.InsertAfter(if_node, prev);
+    sub_zipper->Remove(goto_node);
+}
+
+void ASTManager::MoveOutward(ASTNode goto_node) {
+    ASTZipper& zipper = goto_node->GetManager();
+    const ASTNode parent = goto_node->GetParent();
+    ASTZipper& zipper2 = parent->GetManager();
+    const ASTNode grandpa = parent->GetParent();
+    const bool is_loop = parent->IsLoop();
+    const bool is_else = parent->IsIfElse();
+    const bool is_if = parent->IsIfThen();
+
+    const ASTNode prev = goto_node->GetPrevious();
+    const ASTNode post = goto_node->GetNext();
+
+    const Expr condition = goto_node->GetGotoCondition();
+    zipper.DetachSingle(goto_node);
+    if (is_loop) {
+        const u32 var_index = NewVariable();
+        const Expr var_condition = MakeExpr<ExprVar>(var_index);
+        const ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
+        const ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, false_condition);
+        zipper2.InsertBefore(var_node_init, parent);
+        zipper.InsertAfter(var_node, prev);
+        goto_node->SetGotoCondition(var_condition);
+        const ASTNode break_node = ASTBase::Make<ASTBreak>(parent, var_condition);
+        zipper.InsertAfter(break_node, var_node);
+    } else if (is_if || is_else) {
+        const u32 var_index = NewVariable();
+        const Expr var_condition = MakeExpr<ExprVar>(var_index);
+        const ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
+        const ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, false_condition);
+        if (is_if) {
+            zipper2.InsertBefore(var_node_init, parent);
+        } else {
+            zipper2.InsertBefore(var_node_init, parent->GetPrevious());
+        }
+        zipper.InsertAfter(var_node, prev);
+        goto_node->SetGotoCondition(var_condition);
+        if (post) {
+            zipper.DetachTail(post);
+            const ASTNode if_node = ASTBase::Make<ASTIfThen>(parent, MakeExprNot(var_condition));
+            ASTZipper* sub_zipper = if_node->GetSubNodes();
+            sub_zipper->Init(post, if_node);
+            zipper.InsertAfter(if_node, var_node);
+        }
+    } else {
+        UNREACHABLE();
+    }
+    const ASTNode next = parent->GetNext();
+    if (is_if && next && next->IsIfElse()) {
+        zipper2.InsertAfter(goto_node, next);
+        goto_node->SetParent(grandpa);
+        return;
+    }
+    zipper2.InsertAfter(goto_node, parent);
+    goto_node->SetParent(grandpa);
+}
+
+class ASTClearer {
+public:
+    ASTClearer() = default;
+
+    void operator()(const ASTProgram& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(const ASTIfThen& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(const ASTIfElse& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()([[maybe_unused]] const ASTBlockEncoded& ast) {}
+
+    void operator()(ASTBlockDecoded& ast) {
+        ast.nodes.clear();
+    }
+
+    void operator()([[maybe_unused]] const ASTVarSet& ast) {}
+
+    void operator()([[maybe_unused]] const ASTLabel& ast) {}
+
+    void operator()([[maybe_unused]] const ASTGoto& ast) {}
+
+    void operator()(const ASTDoWhile& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()([[maybe_unused]] const ASTReturn& ast) {}
+
+    void operator()([[maybe_unused]] const ASTBreak& ast) {}
+
+    void Visit(const ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+        node->Clear();
+    }
+};
+
+void ASTManager::Clear() {
+    if (!main_node) {
+        return;
+    }
+    ASTClearer clearer{};
+    clearer.Visit(main_node);
+    main_node.reset();
+    program = nullptr;
+    labels_map.clear();
+    labels.clear();
+    gotos.clear();
+}
+
+} // namespace VideoCommon::Shader

src/video_core/shader/ast.h

@@ -0,0 +1,400 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <list>
+#include <memory>
+#include <optional>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "video_core/shader/expr.h"
+#include "video_core/shader/node.h"
+
+namespace VideoCommon::Shader {
+
+class ASTBase;
+class ASTBlockDecoded;
+class ASTBlockEncoded;
+class ASTBreak;
+class ASTDoWhile;
+class ASTGoto;
+class ASTIfElse;
+class ASTIfThen;
+class ASTLabel;
+class ASTProgram;
+class ASTReturn;
+class ASTVarSet;
+
+using ASTData = std::variant<ASTProgram, ASTIfThen, ASTIfElse, ASTBlockEncoded, ASTBlockDecoded,
+                             ASTVarSet, ASTGoto, ASTLabel, ASTDoWhile, ASTReturn, ASTBreak>;
+
+using ASTNode = std::shared_ptr<ASTBase>;
+
+enum class ASTZipperType : u32 {
+    Program,
+    IfThen,
+    IfElse,
+    Loop,
+};
+
+class ASTZipper final {
+public:
+    explicit ASTZipper();
+
+    void Init(ASTNode first, ASTNode parent);
+
+    ASTNode GetFirst() const {
+        return first;
+    }
+
+    ASTNode GetLast() const {
+        return last;
+    }
+
+    void PushBack(ASTNode new_node);
+    void PushFront(ASTNode new_node);
+    void InsertAfter(ASTNode new_node, ASTNode at_node);
+    void InsertBefore(ASTNode new_node, ASTNode at_node);
+    void DetachTail(ASTNode node);
+    void DetachSingle(ASTNode node);
+    void DetachSegment(ASTNode start, ASTNode end);
+    void Remove(ASTNode node);
+
+    ASTNode first{};
+    ASTNode last{};
+};
+
+class ASTProgram {
+public:
+    ASTZipper nodes{};
+};
+
+class ASTIfThen {
+public:
+    explicit ASTIfThen(Expr condition) : condition{std::move(condition)} {}
+    Expr condition;
+    ASTZipper nodes{};
+};
+
+class ASTIfElse {
+public:
+    ASTZipper nodes{};
+};
+
+class ASTBlockEncoded {
+public:
+    explicit ASTBlockEncoded(u32 start, u32 end) : start{start}, end{end} {}
+    u32 start;
+    u32 end;
+};
+
+class ASTBlockDecoded {
+public:
+    explicit ASTBlockDecoded(NodeBlock&& new_nodes) : nodes(std::move(new_nodes)) {}
+    NodeBlock nodes;
+};
+
+class ASTVarSet {
+public:
+    explicit ASTVarSet(u32 index, Expr condition) : index{index}, condition{std::move(condition)} {}
+    u32 index;
+    Expr condition;
+};
+
+class ASTLabel {
+public:
+    explicit ASTLabel(u32 index) : index{index} {}
+    u32 index;
+    bool unused{};
+};
+
+class ASTGoto {
+public:
+    explicit ASTGoto(Expr condition, u32 label) : condition{std::move(condition)}, label{label} {}
+    Expr condition;
+    u32 label;
+};
+
+class ASTDoWhile {
+public:
+    explicit ASTDoWhile(Expr condition) : condition{std::move(condition)} {}
+    Expr condition;
+    ASTZipper nodes{};
+};
+
+class ASTReturn {
+public:
+    explicit ASTReturn(Expr condition, bool kills)
+        : condition{std::move(condition)}, kills{kills} {}
+    Expr condition;
+    bool kills;
+};
+
+class ASTBreak {
+public:
+    explicit ASTBreak(Expr condition) : condition{std::move(condition)} {}
+    Expr condition;
+};
+
+class ASTBase {
+public:
+    explicit ASTBase(ASTNode parent, ASTData data)
+        : data{std::move(data)}, parent{std::move(parent)} {}
+
+    template <class U, class... Args>
+    static ASTNode Make(ASTNode parent, Args&&... args) {
+        return std::make_shared<ASTBase>(std::move(parent),
+                                         ASTData(U(std::forward<Args>(args)...)));
+    }
+
+    void SetParent(ASTNode new_parent) {
+        parent = std::move(new_parent);
+    }
+
+    ASTNode& GetParent() {
+        return parent;
+    }
+
+    const ASTNode& GetParent() const {
+        return parent;
+    }
+
+    u32 GetLevel() const {
+        u32 level = 0;
+        auto next_parent = parent;
+        while (next_parent) {
+            next_parent = next_parent->GetParent();
+            level++;
+        }
+        return level;
+    }
+
+    ASTData* GetInnerData() {
+        return &data;
+    }
+
+    const ASTData* GetInnerData() const {
+        return &data;
+    }
+
+    ASTNode GetNext() const {
+        return next;
+    }
+
+    ASTNode GetPrevious() const {
+        return previous;
+    }
+
+    ASTZipper& GetManager() {
+        return *manager;
+    }
+
+    const ASTZipper& GetManager() const {
+        return *manager;
+    }
+
+    std::optional<u32> GetGotoLabel() const {
+        auto inner = std::get_if<ASTGoto>(&data);
+        if (inner) {
+            return {inner->label};
+        }
+        return {};
+    }
+
+    Expr GetGotoCondition() const {
+        auto inner = std::get_if<ASTGoto>(&data);
+        if (inner) {
+            return inner->condition;
+        }
+        return nullptr;
+    }
+
+    void MarkLabelUnused() {
+        auto inner = std::get_if<ASTLabel>(&data);
+        if (inner) {
+            inner->unused = true;
+        }
+    }
+
+    bool IsLabelUnused() const {
+        auto inner = std::get_if<ASTLabel>(&data);
+        if (inner) {
+            return inner->unused;
+        }
+        return true;
+    }
+
+    std::optional<u32> GetLabelIndex() const {
+        auto inner = std::get_if<ASTLabel>(&data);
+        if (inner) {
+            return {inner->index};
+        }
+        return {};
+    }
+
+    Expr GetIfCondition() const {
+        auto inner = std::get_if<ASTIfThen>(&data);
+        if (inner) {
+            return inner->condition;
+        }
+        return nullptr;
+    }
+
+    void SetGotoCondition(Expr new_condition) {
+        auto inner = std::get_if<ASTGoto>(&data);
+        if (inner) {
+            inner->condition = std::move(new_condition);
+        }
+    }
+
+    bool IsIfThen() const {
+        return std::holds_alternative<ASTIfThen>(data);
+    }
+
+    bool IsIfElse() const {
+        return std::holds_alternative<ASTIfElse>(data);
+    }
+
+    bool IsBlockEncoded() const {
+        return std::holds_alternative<ASTBlockEncoded>(data);
+    }
+
+    void TransformBlockEncoded(NodeBlock&& nodes) {
+        data = ASTBlockDecoded(std::move(nodes));
+    }
+
+    bool IsLoop() const {
+        return std::holds_alternative<ASTDoWhile>(data);
+    }
+
+    ASTZipper* GetSubNodes() {
+        if (std::holds_alternative<ASTProgram>(data)) {
+            return &std::get_if<ASTProgram>(&data)->nodes;
+        }
+        if (std::holds_alternative<ASTIfThen>(data)) {
+            return &std::get_if<ASTIfThen>(&data)->nodes;
+        }
+        if (std::holds_alternative<ASTIfElse>(data)) {
+            return &std::get_if<ASTIfElse>(&data)->nodes;
+        }
+        if (std::holds_alternative<ASTDoWhile>(data)) {
+            return &std::get_if<ASTDoWhile>(&data)->nodes;
+        }
+        return nullptr;
+    }
+
+    void Clear() {
+        next.reset();
+        previous.reset();
+        parent.reset();
+        manager = nullptr;
+    }
+
+private:
+    friend class ASTZipper;
+
+    ASTData data;
+    ASTNode parent{};
+    ASTNode next{};
+    ASTNode previous{};
+    ASTZipper* manager{};
+};
+
+class ASTManager final {
+public:
+    ASTManager(bool full_decompile, bool disable_else_derivation);
+    ~ASTManager();
+
+    ASTManager(const ASTManager& o) = delete;
+    ASTManager& operator=(const ASTManager& other) = delete;
+
+    ASTManager(ASTManager&& other) noexcept = default;
+    ASTManager& operator=(ASTManager&& other) noexcept = default;
+
+    void Init();
+
+    void DeclareLabel(u32 address);
+
+    void InsertLabel(u32 address);
+
+    void InsertGoto(Expr condition, u32 address);
+
+    void InsertBlock(u32 start_address, u32 end_address);
+
+    void InsertReturn(Expr condition, bool kills);
+
+    std::string Print();
+
+    void Decompile();
+
+    void ShowCurrentState(std::string_view state);
+
+    void SanityCheck();
+
+    void Clear();
+
+    bool IsFullyDecompiled() const {
+        if (full_decompile) {
+            return gotos.empty();
+        }
+
+        for (ASTNode goto_node : gotos) {
+            auto label_index = goto_node->GetGotoLabel();
+            if (!label_index) {
+                return false;
+            }
+            ASTNode glabel = labels[*label_index];
+            if (IsBackwardsJump(goto_node, glabel)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    ASTNode GetProgram() const {
+        return main_node;
+    }
+
+    u32 GetVariables() const {
+        return variables;
+    }
+
+    const std::vector<ASTNode>& GetLabels() const {
+        return labels;
+    }
+
+private:
+    bool IsBackwardsJump(ASTNode goto_node, ASTNode label_node) const;
+
+    bool IndirectlyRelated(const ASTNode& first, const ASTNode& second) const;
+
+    bool DirectlyRelated(const ASTNode& first, const ASTNode& second) const;
+
+    void EncloseDoWhile(ASTNode goto_node, ASTNode label);
+
+    void EncloseIfThen(ASTNode goto_node, ASTNode label);
+
+    void MoveOutward(ASTNode goto_node);
+
+    u32 NewVariable() {
+        return variables++;
+    }
+
+    bool full_decompile{};
+    bool disable_else_derivation{};
+    std::unordered_map<u32, u32> labels_map{};
+    u32 labels_count{};
+    std::vector<ASTNode> labels{};
+    std::list<ASTNode> gotos{};
+    u32 variables{};
+    ASTProgram* program{};
+    ASTNode main_node{};
+    Expr false_condition{};
+};
+
+} // namespace VideoCommon::Shader

src/video_core/shader/compiler_settings.cpp

@@ -0,0 +1,26 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "video_core/shader/compiler_settings.h"
+
+namespace VideoCommon::Shader {
+
+std::string CompileDepthAsString(const CompileDepth cd) {
+    switch (cd) {
+    case CompileDepth::BruteForce:
+        return "Brute Force Compile";
+    case CompileDepth::FlowStack:
+        return "Simple Flow Stack Mode";
+    case CompileDepth::NoFlowStack:
+        return "Remove Flow Stack";
+    case CompileDepth::DecompileBackwards:
+        return "Decompile Backward Jumps";
+    case CompileDepth::FullDecompile:
+        return "Full Decompilation";
+    default:
+        return "Unknown Compiler Process";
+    }
+}
+
+} // namespace VideoCommon::Shader

src/video_core/shader/compiler_settings.h

@@ -0,0 +1,26 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "video_core/engines/shader_bytecode.h"
+
+namespace VideoCommon::Shader {
+
+enum class CompileDepth : u32 {
+    BruteForce = 0,
+    FlowStack = 1,
+    NoFlowStack = 2,
+    DecompileBackwards = 3,
+    FullDecompile = 4,
+};
+
+std::string CompileDepthAsString(CompileDepth cd);
+
+struct CompilerSettings {
+    CompileDepth depth{CompileDepth::NoFlowStack};
+    bool disable_else_derivation{true};
+};
+
+} // namespace VideoCommon::Shader

src/video_core/shader/control_flow.cpp

@@ -4,13 +4,14 @@
 
 #include <list>
 #include <map>
+#include <set>
 #include <stack>
 #include <unordered_map>
-#include <unordered_set>
 #include <vector>
 
 #include "common/assert.h"
 #include "common/common_types.h"
+#include "video_core/shader/ast.h"
 #include "video_core/shader/control_flow.h"
 #include "video_core/shader/shader_ir.h"
 
@@ -64,12 +65,13 @@ struct CFGRebuildState {
     std::list<u32> inspect_queries{};
     std::list<Query> queries{};
     std::unordered_map<u32, u32> registered{};
-    std::unordered_set<u32> labels{};
+    std::set<u32> labels{};
     std::map<u32, u32> ssy_labels{};
     std::map<u32, u32> pbk_labels{};
     std::unordered_map<u32, BlockStack> stacks{};
     const ProgramCode& program_code;
     const std::size_t program_size;
+    ASTManager* manager;
 };
 
 enum class BlockCollision : u32 { None, Found, Inside };
@@ -415,38 +417,133 @@ bool TryQuery(CFGRebuildState& state) {
 }
 } // Anonymous namespace
 
-std::optional<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code,
-                                              std::size_t program_size, u32 start_address) {
-    CFGRebuildState state{program_code, program_size, start_address};
+void InsertBranch(ASTManager& mm, const BlockBranchInfo& branch) {
+    const auto get_expr = ([&](const Condition& cond) -> Expr {
+        Expr result{};
+        if (cond.cc != ConditionCode::T) {
+            result = MakeExpr<ExprCondCode>(cond.cc);
+        }
+        if (cond.predicate != Pred::UnusedIndex) {
+            u32 pred = static_cast<u32>(cond.predicate);
+            bool negate = false;
+            if (pred > 7) {
+                negate = true;
+                pred -= 8;
+            }
+            Expr extra = MakeExpr<ExprPredicate>(pred);
+            if (negate) {
+                extra = MakeExpr<ExprNot>(extra);
+            }
+            if (result) {
+                return MakeExpr<ExprAnd>(extra, result);
+            }
+            return extra;
+        }
+        if (result) {
+            return result;
+        }
+        return MakeExpr<ExprBoolean>(true);
+    });
+    if (branch.address < 0) {
+        if (branch.kill) {
+            mm.InsertReturn(get_expr(branch.condition), true);
+            return;
+        }
+        mm.InsertReturn(get_expr(branch.condition), false);
+        return;
+    }
+    mm.InsertGoto(get_expr(branch.condition), branch.address);
+}
 
+void DecompileShader(CFGRebuildState& state) {
+    state.manager->Init();
+    for (auto label : state.labels) {
+        state.manager->DeclareLabel(label);
+    }
+    for (auto& block : state.block_info) {
+        if (state.labels.count(block.start) != 0) {
+            state.manager->InsertLabel(block.start);
+        }
+        u32 end = block.branch.ignore ? block.end + 1 : block.end;
+        state.manager->InsertBlock(block.start, end);
+        if (!block.branch.ignore) {
+            InsertBranch(*state.manager, block.branch);
+        }
+    }
+    state.manager->Decompile();
+}
+
+std::unique_ptr<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code, u32 program_size,
+                                                u32 start_address,
+                                                const CompilerSettings& settings) {
+    auto result_out = std::make_unique<ShaderCharacteristics>();
+    if (settings.depth == CompileDepth::BruteForce) {
+        result_out->settings.depth = CompileDepth::BruteForce;
+        return result_out;
+    }
+
+    CFGRebuildState state{program_code, program_size, start_address};
     // Inspect Code and generate blocks
     state.labels.clear();
     state.labels.emplace(start_address);
     state.inspect_queries.push_back(state.start);
     while (!state.inspect_queries.empty()) {
         if (!TryInspectAddress(state)) {
-            return {};
+            result_out->settings.depth = CompileDepth::BruteForce;
+            return result_out;
         }
     }
 
-    // Decompile Stacks
-    state.queries.push_back(Query{state.start, {}, {}});
-    bool decompiled = true;
-    while (!state.queries.empty()) {
-        if (!TryQuery(state)) {
-            decompiled = false;
-            break;
+    bool use_flow_stack = true;
+
+    bool decompiled = false;
+
+    if (settings.depth != CompileDepth::FlowStack) {
+        // Decompile Stacks
+        state.queries.push_back(Query{state.start, {}, {}});
+        decompiled = true;
+        while (!state.queries.empty()) {
+            if (!TryQuery(state)) {
+                decompiled = false;
+                break;
+            }
         }
     }
 
+    use_flow_stack = !decompiled;
+
     // Sort and organize results
     std::sort(state.block_info.begin(), state.block_info.end(),
-              [](const BlockInfo& a, const BlockInfo& b) { return a.start < b.start; });
-    ShaderCharacteristics result_out{};
-    result_out.decompilable = decompiled;
-    result_out.start = start_address;
-    result_out.end = start_address;
-    for (const auto& block : state.block_info) {
+              [](const BlockInfo& a, const BlockInfo& b) -> bool { return a.start < b.start; });
+    if (decompiled && settings.depth != CompileDepth::NoFlowStack) {
+        ASTManager manager{settings.depth != CompileDepth::DecompileBackwards,
+                           settings.disable_else_derivation};
+        state.manager = &manager;
+        DecompileShader(state);
+        decompiled = state.manager->IsFullyDecompiled();
+        if (!decompiled) {
+            if (settings.depth == CompileDepth::FullDecompile) {
+                LOG_CRITICAL(HW_GPU, "Failed to remove all the gotos!:");
+            } else {
+                LOG_CRITICAL(HW_GPU, "Failed to remove all backward gotos!:");
+            }
+            state.manager->ShowCurrentState("Of Shader");
+            state.manager->Clear();
+        } else {
+            auto characteristics = std::make_unique<ShaderCharacteristics>();
+            characteristics->start = start_address;
+            characteristics->settings.depth = settings.depth;
+            characteristics->manager = std::move(manager);
+            characteristics->end = state.block_info.back().end + 1;
+            return characteristics;
+        }
+    }
+
+    result_out->start = start_address;
+    result_out->settings.depth =
+        use_flow_stack ? CompileDepth::FlowStack : CompileDepth::NoFlowStack;
+    result_out->blocks.clear();
+    for (auto& block : state.block_info) {
         ShaderBlock new_block{};
         new_block.start = block.start;
         new_block.end = block.end;
@@ -456,26 +553,26 @@ std::optional<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code,
             new_block.branch.kills = block.branch.kill;
             new_block.branch.address = block.branch.address;
         }
-        result_out.end = std::max(result_out.end, block.end);
-        result_out.blocks.push_back(new_block);
+        result_out->end = std::max(result_out->end, block.end);
+        result_out->blocks.push_back(new_block);
     }
-    if (result_out.decompilable) {
-        result_out.labels = std::move(state.labels);
-        return {std::move(result_out)};
+    if (!use_flow_stack) {
+        result_out->labels = std::move(state.labels);
+        return result_out;
     }
 
-    // If it's not decompilable, merge the unlabelled blocks together
-    auto back = result_out.blocks.begin();
+    auto back = result_out->blocks.begin();
     auto next = std::next(back);
-    while (next != result_out.blocks.end()) {
+    while (next != result_out->blocks.end()) {
         if (state.labels.count(next->start) == 0 && next->start == back->end + 1) {
             back->end = next->end;
-            next = result_out.blocks.erase(next);
+            next = result_out->blocks.erase(next);
             continue;
         }
         back = next;
         ++next;
     }
-    return {std::move(result_out)};
+
+    return result_out;
 }
 } // namespace VideoCommon::Shader

src/video_core/shader/control_flow.h

@@ -6,9 +6,11 @@
 
 #include <list>
 #include <optional>
-#include <unordered_set>
+#include <set>
 
 #include "video_core/engines/shader_bytecode.h"
+#include "video_core/shader/ast.h"
+#include "video_core/shader/compiler_settings.h"
 #include "video_core/shader/shader_ir.h"
 
 namespace VideoCommon::Shader {
@@ -67,13 +69,15 @@ struct ShaderBlock {
 
 struct ShaderCharacteristics {
     std::list<ShaderBlock> blocks{};
-    bool decompilable{};
+    std::set<u32> labels{};
     u32 start{};
     u32 end{};
-    std::unordered_set<u32> labels{};
+    ASTManager manager{true, true};
+    CompilerSettings settings{};
 };
 
-std::optional<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code,
-                                              std::size_t program_size, u32 start_address);
+std::unique_ptr<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code, u32 program_size,
+                                                u32 start_address,
+                                                const CompilerSettings& settings);
 
 } // namespace VideoCommon::Shader

src/video_core/shader/decode.cpp

@@ -35,58 +35,138 @@ constexpr bool IsSchedInstruction(u32 offset, u32 main_offset) {
 
 } // namespace
 
+class ASTDecoder {
+public:
+    ASTDecoder(ShaderIR& ir) : ir(ir) {}
+
+    void operator()(ASTProgram& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(ASTIfThen& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(ASTIfElse& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(ASTBlockEncoded& ast) {}
+
+    void operator()(ASTBlockDecoded& ast) {}
+
+    void operator()(ASTVarSet& ast) {}
+
+    void operator()(ASTLabel& ast) {}
+
+    void operator()(ASTGoto& ast) {}
+
+    void operator()(ASTDoWhile& ast) {
+        ASTNode current = ast.nodes.GetFirst();
+        while (current) {
+            Visit(current);
+            current = current->GetNext();
+        }
+    }
+
+    void operator()(ASTReturn& ast) {}
+
+    void operator()(ASTBreak& ast) {}
+
+    void Visit(ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+        if (node->IsBlockEncoded()) {
+            auto block = std::get_if<ASTBlockEncoded>(node->GetInnerData());
+            NodeBlock bb = ir.DecodeRange(block->start, block->end);
+            node->TransformBlockEncoded(std::move(bb));
+        }
+    }
+
+private:
+    ShaderIR& ir;
+};
+
 void ShaderIR::Decode() {
     std::memcpy(&header, program_code.data(), sizeof(Tegra::Shader::Header));
 
-    disable_flow_stack = false;
-    const auto info = ScanFlow(program_code, program_size, main_offset);
-    if (info) {
-        const auto& shader_info = *info;
-        coverage_begin = shader_info.start;
-        coverage_end = shader_info.end;
-        if (shader_info.decompilable) {
-            disable_flow_stack = true;
-            const auto insert_block = [this](NodeBlock& nodes, u32 label) {
-                if (label == static_cast<u32>(exit_branch)) {
-                    return;
-                }
-                basic_blocks.insert({label, nodes});
-            };
-            const auto& blocks = shader_info.blocks;
-            NodeBlock current_block;
-            u32 current_label = static_cast<u32>(exit_branch);
-            for (auto& block : blocks) {
-                if (shader_info.labels.count(block.start) != 0) {
-                    insert_block(current_block, current_label);
-                    current_block.clear();
-                    current_label = block.start;
-                }
-                if (!block.ignore_branch) {
-                    DecodeRangeInner(current_block, block.start, block.end);
-                    InsertControlFlow(current_block, block);
-                } else {
-                    DecodeRangeInner(current_block, block.start, block.end + 1);
-                }
-            }
-            insert_block(current_block, current_label);
-            return;
-        }
-        LOG_WARNING(HW_GPU, "Flow Stack Removing Failed! Falling back to old method");
-        // we can't decompile it, fallback to standard method
+    decompiled = false;
+    auto info = ScanFlow(program_code, program_size, main_offset, settings);
+    auto& shader_info = *info;
+    coverage_begin = shader_info.start;
+    coverage_end = shader_info.end;
+    switch (shader_info.settings.depth) {
+    case CompileDepth::FlowStack: {
         for (const auto& block : shader_info.blocks) {
             basic_blocks.insert({block.start, DecodeRange(block.start, block.end + 1)});
         }
-        return;
+        break;
     }
-    LOG_WARNING(HW_GPU, "Flow Analysis Failed! Falling back to brute force compiling");
-
-    // Now we need to deal with an undecompilable shader. We need to brute force
-    // a shader that captures every position.
-    coverage_begin = main_offset;
-    const u32 shader_end = static_cast<u32>(program_size / sizeof(u64));
-    coverage_end = shader_end;
-    for (u32 label = main_offset; label < shader_end; label++) {
-        basic_blocks.insert({label, DecodeRange(label, label + 1)});
+    case CompileDepth::NoFlowStack: {
+        disable_flow_stack = true;
+        const auto insert_block = [this](NodeBlock& nodes, u32 label) {
+            if (label == static_cast<u32>(exit_branch)) {
+                return;
+            }
+            basic_blocks.insert({label, nodes});
+        };
+        const auto& blocks = shader_info.blocks;
+        NodeBlock current_block;
+        u32 current_label = static_cast<u32>(exit_branch);
+        for (auto& block : blocks) {
+            if (shader_info.labels.count(block.start) != 0) {
+                insert_block(current_block, current_label);
+                current_block.clear();
+                current_label = block.start;
+            }
+            if (!block.ignore_branch) {
+                DecodeRangeInner(current_block, block.start, block.end);
+                InsertControlFlow(current_block, block);
+            } else {
+                DecodeRangeInner(current_block, block.start, block.end + 1);
+            }
+        }
+        insert_block(current_block, current_label);
+        break;
+    }
+    case CompileDepth::DecompileBackwards:
+    case CompileDepth::FullDecompile: {
+        program_manager = std::move(shader_info.manager);
+        disable_flow_stack = true;
+        decompiled = true;
+        ASTDecoder decoder{*this};
+        ASTNode program = GetASTProgram();
+        decoder.Visit(program);
+        break;
+    }
+    default:
+        LOG_CRITICAL(HW_GPU, "Unknown decompilation mode!");
+        [[fallthrough]];
+    case CompileDepth::BruteForce: {
+        coverage_begin = main_offset;
+        const u32 shader_end = static_cast<u32>(program_size / sizeof(u64));
+        coverage_end = shader_end;
+        for (u32 label = main_offset; label < shader_end; label++) {
+            basic_blocks.insert({label, DecodeRange(label, label + 1)});
+        }
+        break;
+    }
+    }
+    if (settings.depth != shader_info.settings.depth) {
+        LOG_WARNING(
+            HW_GPU, "Decompiling to this setting \"{}\" failed, downgrading to this setting \"{}\"",
+            CompileDepthAsString(settings.depth), CompileDepthAsString(shader_info.settings.depth));
     }
 }
 

src/video_core/shader/expr.cpp

@@ -0,0 +1,93 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <memory>
+#include <variant>
+
+#include "video_core/shader/expr.h"
+
+namespace VideoCommon::Shader {
+namespace {
+bool ExprIsBoolean(const Expr& expr) {
+    return std::holds_alternative<ExprBoolean>(*expr);
+}
+
+bool ExprBooleanGet(const Expr& expr) {
+    return std::get_if<ExprBoolean>(expr.get())->value;
+}
+} // Anonymous namespace
+
+bool ExprAnd::operator==(const ExprAnd& b) const {
+    return (*operand1 == *b.operand1) && (*operand2 == *b.operand2);
+}
+
+bool ExprAnd::operator!=(const ExprAnd& b) const {
+    return !operator==(b);
+}
+
+bool ExprOr::operator==(const ExprOr& b) const {
+    return (*operand1 == *b.operand1) && (*operand2 == *b.operand2);
+}
+
+bool ExprOr::operator!=(const ExprOr& b) const {
+    return !operator==(b);
+}
+
+bool ExprNot::operator==(const ExprNot& b) const {
+    return *operand1 == *b.operand1;
+}
+
+bool ExprNot::operator!=(const ExprNot& b) const {
+    return !operator==(b);
+}
+
+Expr MakeExprNot(Expr first) {
+    if (std::holds_alternative<ExprNot>(*first)) {
+        return std::get_if<ExprNot>(first.get())->operand1;
+    }
+    return MakeExpr<ExprNot>(std::move(first));
+}
+
+Expr MakeExprAnd(Expr first, Expr second) {
+    if (ExprIsBoolean(first)) {
+        return ExprBooleanGet(first) ? second : first;
+    }
+    if (ExprIsBoolean(second)) {
+        return ExprBooleanGet(second) ? first : second;
+    }
+    return MakeExpr<ExprAnd>(std::move(first), std::move(second));
+}
+
+Expr MakeExprOr(Expr first, Expr second) {
+    if (ExprIsBoolean(first)) {
+        return ExprBooleanGet(first) ? first : second;
+    }
+    if (ExprIsBoolean(second)) {
+        return ExprBooleanGet(second) ? second : first;
+    }
+    return MakeExpr<ExprOr>(std::move(first), std::move(second));
+}
+
+bool ExprAreEqual(const Expr& first, const Expr& second) {
+    return (*first) == (*second);
+}
+
+bool ExprAreOpposite(const Expr& first, const Expr& second) {
+    if (std::holds_alternative<ExprNot>(*first)) {
+        return ExprAreEqual(std::get_if<ExprNot>(first.get())->operand1, second);
+    }
+    if (std::holds_alternative<ExprNot>(*second)) {
+        return ExprAreEqual(std::get_if<ExprNot>(second.get())->operand1, first);
+    }
+    return false;
+}
+
+bool ExprIsTrue(const Expr& first) {
+    if (ExprIsBoolean(first)) {
+        return ExprBooleanGet(first);
+    }
+    return false;
+}
+
+} // namespace VideoCommon::Shader

src/video_core/shader/expr.h

@@ -0,0 +1,139 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <variant>
+
+#include "video_core/engines/shader_bytecode.h"
+
+namespace VideoCommon::Shader {
+
+using Tegra::Shader::ConditionCode;
+using Tegra::Shader::Pred;
+
+class ExprAnd;
+class ExprBoolean;
+class ExprCondCode;
+class ExprNot;
+class ExprOr;
+class ExprPredicate;
+class ExprVar;
+
+using ExprData =
+    std::variant<ExprVar, ExprCondCode, ExprPredicate, ExprNot, ExprOr, ExprAnd, ExprBoolean>;
+using Expr = std::shared_ptr<ExprData>;
+
+class ExprAnd final {
+public:
+    explicit ExprAnd(Expr a, Expr b) : operand1{std::move(a)}, operand2{std::move(b)} {}
+
+    bool operator==(const ExprAnd& b) const;
+    bool operator!=(const ExprAnd& b) const;
+
+    Expr operand1;
+    Expr operand2;
+};
+
+class ExprOr final {
+public:
+    explicit ExprOr(Expr a, Expr b) : operand1{std::move(a)}, operand2{std::move(b)} {}
+
+    bool operator==(const ExprOr& b) const;
+    bool operator!=(const ExprOr& b) const;
+
+    Expr operand1;
+    Expr operand2;
+};
+
+class ExprNot final {
+public:
+    explicit ExprNot(Expr a) : operand1{std::move(a)} {}
+
+    bool operator==(const ExprNot& b) const;
+    bool operator!=(const ExprNot& b) const;
+
+    Expr operand1;
+};
+
+class ExprVar final {
+public:
+    explicit ExprVar(u32 index) : var_index{index} {}
+
+    bool operator==(const ExprVar& b) const {
+        return var_index == b.var_index;
+    }
+
+    bool operator!=(const ExprVar& b) const {
+        return !operator==(b);
+    }
+
+    u32 var_index;
+};
+
+class ExprPredicate final {
+public:
+    explicit ExprPredicate(u32 predicate) : predicate{predicate} {}
+
+    bool operator==(const ExprPredicate& b) const {
+        return predicate == b.predicate;
+    }
+
+    bool operator!=(const ExprPredicate& b) const {
+        return !operator==(b);
+    }
+
+    u32 predicate;
+};
+
+class ExprCondCode final {
+public:
+    explicit ExprCondCode(ConditionCode cc) : cc{cc} {}
+
+    bool operator==(const ExprCondCode& b) const {
+        return cc == b.cc;
+    }
+
+    bool operator!=(const ExprCondCode& b) const {
+        return !operator==(b);
+    }
+
+    ConditionCode cc;
+};
+
+class ExprBoolean final {
+public:
+    explicit ExprBoolean(bool val) : value{val} {}
+
+    bool operator==(const ExprBoolean& b) const {
+        return value == b.value;
+    }
+
+    bool operator!=(const ExprBoolean& b) const {
+        return !operator==(b);
+    }
+
+    bool value;
+};
+
+template <typename T, typename... Args>
+Expr MakeExpr(Args&&... args) {
+    static_assert(std::is_convertible_v<T, ExprData>);
+    return std::make_shared<ExprData>(T(std::forward<Args>(args)...));
+}
+
+bool ExprAreEqual(const Expr& first, const Expr& second);
+
+bool ExprAreOpposite(const Expr& first, const Expr& second);
+
+Expr MakeExprNot(Expr first);
+
+Expr MakeExprAnd(Expr first, Expr second);
+
+Expr MakeExprOr(Expr first, Expr second);
+
+bool ExprIsTrue(const Expr& first);
+
+} // namespace VideoCommon::Shader

src/video_core/shader/shader_ir.cpp

@@ -22,8 +22,10 @@ using Tegra::Shader::PredCondition;
 using Tegra::Shader::PredOperation;
 using Tegra::Shader::Register;
 
-ShaderIR::ShaderIR(const ProgramCode& program_code, u32 main_offset, const std::size_t size)
-    : program_code{program_code}, main_offset{main_offset}, program_size{size} {
+ShaderIR::ShaderIR(const ProgramCode& program_code, u32 main_offset, const std::size_t size,
+                   CompilerSettings settings)
+    : program_code{program_code}, main_offset{main_offset}, program_size{size}, basic_blocks{},
+      program_manager{true, true}, settings{settings} {
     Decode();
 }
 
@@ -137,7 +139,7 @@ Node ShaderIR::GetOutputAttribute(Attribute::Index index, u64 element, Node buff
     return MakeNode<AbufNode>(index, static_cast<u32>(element), std::move(buffer));
 }
 
-Node ShaderIR::GetInternalFlag(InternalFlag flag, bool negated) {
+Node ShaderIR::GetInternalFlag(InternalFlag flag, bool negated) const {
     const Node node = MakeNode<InternalFlagNode>(flag);
     if (negated) {
         return Operation(OperationCode::LogicalNegate, node);
@@ -367,13 +369,13 @@ OperationCode ShaderIR::GetPredicateCombiner(PredOperation operation) {
     return op->second;
 }
 
-Node ShaderIR::GetConditionCode(Tegra::Shader::ConditionCode cc) {
+Node ShaderIR::GetConditionCode(Tegra::Shader::ConditionCode cc) const {
     switch (cc) {
     case Tegra::Shader::ConditionCode::NEU:
         return GetInternalFlag(InternalFlag::Zero, true);
     default:
         UNIMPLEMENTED_MSG("Unimplemented condition code: {}", static_cast<u32>(cc));
-        return GetPredicate(static_cast<u64>(Pred::NeverExecute));
+        return MakeNode<PredicateNode>(Pred::NeverExecute, false);
     }
 }
 

src/video_core/shader/shader_ir.h

@@ -15,6 +15,8 @@
 #include "video_core/engines/maxwell_3d.h"
 #include "video_core/engines/shader_bytecode.h"
 #include "video_core/engines/shader_header.h"
+#include "video_core/shader/ast.h"
+#include "video_core/shader/compiler_settings.h"
 #include "video_core/shader/node.h"
 
 namespace VideoCommon::Shader {
@@ -64,7 +66,8 @@ struct GlobalMemoryUsage {
 
 class ShaderIR final {
 public:
-    explicit ShaderIR(const ProgramCode& program_code, u32 main_offset, std::size_t size);
+    explicit ShaderIR(const ProgramCode& program_code, u32 main_offset, std::size_t size,
+                      CompilerSettings settings);
     ~ShaderIR();
 
     const std::map<u32, NodeBlock>& GetBasicBlocks() const {
@@ -144,11 +147,31 @@ public:
         return disable_flow_stack;
     }
 
+    bool IsDecompiled() const {
+        return decompiled;
+    }
+
+    const ASTManager& GetASTManager() const {
+        return program_manager;
+    }
+
+    ASTNode GetASTProgram() const {
+        return program_manager.GetProgram();
+    }
+
+    u32 GetASTNumVariables() const {
+        return program_manager.GetVariables();
+    }
+
     u32 ConvertAddressToNvidiaSpace(const u32 address) const {
         return (address - main_offset) * sizeof(Tegra::Shader::Instruction);
     }
 
+    /// Returns a condition code evaluated from internal flags
+    Node GetConditionCode(Tegra::Shader::ConditionCode cc) const;
+
 private:
+    friend class ASTDecoder;
     void Decode();
 
     NodeBlock DecodeRange(u32 begin, u32 end);
@@ -213,7 +236,7 @@ private:
     /// Generates a node representing an output attribute. Keeps track of used attributes.
     Node GetOutputAttribute(Tegra::Shader::Attribute::Index index, u64 element, Node buffer);
     /// Generates a node representing an internal flag
-    Node GetInternalFlag(InternalFlag flag, bool negated = false);
+    Node GetInternalFlag(InternalFlag flag, bool negated = false) const;
     /// Generates a node representing a local memory address
     Node GetLocalMemory(Node address);
     /// Generates a node representing a shared memory address
@@ -271,9 +294,6 @@ private:
     /// Returns a predicate combiner operation
     OperationCode GetPredicateCombiner(Tegra::Shader::PredOperation operation);
 
-    /// Returns a condition code evaluated from internal flags
-    Node GetConditionCode(Tegra::Shader::ConditionCode cc);
-
     /// Accesses a texture sampler
     const Sampler& GetSampler(const Tegra::Shader::Sampler& sampler,
                               Tegra::Shader::TextureType type, bool is_array, bool is_shadow);
@@ -357,6 +377,7 @@ private:
     const ProgramCode& program_code;
     const u32 main_offset;
     const std::size_t program_size;
+    bool decompiled{};
     bool disable_flow_stack{};
 
     u32 coverage_begin{};
@@ -364,6 +385,8 @@ private:
 
     std::map<u32, NodeBlock> basic_blocks;
     NodeBlock global_code;
+    ASTManager program_manager;
+    CompilerSettings settings{};
 
     std::set<u32> used_registers;
     std::set<Tegra::Shader::Pred> used_predicates;

src/video_core/texture_cache/texture_cache.h

@@ -224,8 +224,13 @@ public:
                      const Tegra::Engines::Fermi2D::Regs::Surface& dst_config,
                      const Tegra::Engines::Fermi2D::Config& copy_config) {
         std::lock_guard lock{mutex};
-        std::pair<TSurface, TView> dst_surface = GetFermiSurface(dst_config);
-        std::pair<TSurface, TView> src_surface = GetFermiSurface(src_config);
+        SurfaceParams src_params = SurfaceParams::CreateForFermiCopySurface(src_config);
+        SurfaceParams dst_params = SurfaceParams::CreateForFermiCopySurface(dst_config);
+        const GPUVAddr src_gpu_addr = src_config.Address();
+        const GPUVAddr dst_gpu_addr = dst_config.Address();
+        DeduceBestBlit(src_params, dst_params, src_gpu_addr, dst_gpu_addr);
+        std::pair<TSurface, TView> dst_surface = GetSurface(dst_gpu_addr, dst_params, true, false);
+        std::pair<TSurface, TView> src_surface = GetSurface(src_gpu_addr, src_params, true, false);
         ImageBlit(src_surface.second, dst_surface.second, copy_config);
         dst_surface.first->MarkAsModified(true, Tick());
     }
@@ -357,6 +362,29 @@ private:
         BufferCopy = 3,
     };
 
+    enum class DeductionType : u32 {
+        DeductionComplete,
+        DeductionIncomplete,
+        DeductionFailed,
+    };
+
+    struct Deduction {
+        DeductionType type{DeductionType::DeductionFailed};
+        TSurface surface{};
+
+        bool Failed() const {
+            return type == DeductionType::DeductionFailed;
+        }
+
+        bool Incomplete() const {
+            return type == DeductionType::DeductionIncomplete;
+        }
+
+        bool IsDepth() const {
+            return surface->GetSurfaceParams().IsPixelFormatZeta();
+        }
+    };
+
     /**
      * `PickStrategy` takes care of selecting a proper strategy to deal with a texture recycle.
      * @param overlaps, the overlapping surfaces registered in the cache.
@@ -691,6 +719,120 @@ private:
                               MatchTopologyResult::FullMatch);
     }
 
+    /**
+     * `DeduceSurface` gets the starting address and parameters of a candidate surface and tries
+     * to find a matching surface within the cache that's similar to it. If there are many textures
+     * or the texture found if entirely incompatible, it will fail. If no texture is found, the
+     * blit will be unsuccessful.
+     * @param gpu_addr, the starting address of the candidate surface.
+     * @param params, the paremeters on the candidate surface.
+     **/
+    Deduction DeduceSurface(const GPUVAddr gpu_addr, const SurfaceParams& params) {
+        const auto host_ptr{system.GPU().MemoryManager().GetPointer(gpu_addr)};
+        const auto cache_addr{ToCacheAddr(host_ptr)};
+
+        if (!cache_addr) {
+            Deduction result{};
+            result.type = DeductionType::DeductionFailed;
+            return result;
+        }
+
+        if (const auto iter = l1_cache.find(cache_addr); iter != l1_cache.end()) {
+            TSurface& current_surface = iter->second;
+            const auto topological_result = current_surface->MatchesTopology(params);
+            if (topological_result != MatchTopologyResult::FullMatch) {
+                Deduction result{};
+                result.type = DeductionType::DeductionFailed;
+                return result;
+            }
+            const auto struct_result = current_surface->MatchesStructure(params);
+            if (struct_result != MatchStructureResult::None &&
+                current_surface->MatchTarget(params.target)) {
+                Deduction result{};
+                result.type = DeductionType::DeductionComplete;
+                result.surface = current_surface;
+                return result;
+            }
+        }
+
+        const std::size_t candidate_size = params.GetGuestSizeInBytes();
+        auto overlaps{GetSurfacesInRegion(cache_addr, candidate_size)};
+
+        if (overlaps.empty()) {
+            Deduction result{};
+            result.type = DeductionType::DeductionIncomplete;
+            return result;
+        }
+
+        if (overlaps.size() > 1) {
+            Deduction result{};
+            result.type = DeductionType::DeductionFailed;
+            return result;
+        } else {
+            Deduction result{};
+            result.type = DeductionType::DeductionComplete;
+            result.surface = overlaps[0];
+            return result;
+        }
+    }
+
+    /**
+     * `DeduceBestBlit` gets the a source and destination starting address and parameters,
+     * and tries to deduce if they are supposed to be depth textures. If so, their
+     * parameters are modified and fixed into so.
+     * @param gpu_addr, the starting address of the candidate surface.
+     * @param params, the parameters on the candidate surface.
+     **/
+    void DeduceBestBlit(SurfaceParams& src_params, SurfaceParams& dst_params,
+                        const GPUVAddr src_gpu_addr, const GPUVAddr dst_gpu_addr) {
+        auto deduced_src = DeduceSurface(src_gpu_addr, src_params);
+        auto deduced_dst = DeduceSurface(src_gpu_addr, src_params);
+        if (deduced_src.Failed() || deduced_dst.Failed()) {
+            return;
+        }
+
+        const bool incomplete_src = deduced_src.Incomplete();
+        const bool incomplete_dst = deduced_dst.Incomplete();
+
+        if (incomplete_src && incomplete_dst) {
+            return;
+        }
+
+        const bool any_incomplete = incomplete_src || incomplete_dst;
+
+        if (!any_incomplete) {
+            if (!(deduced_src.IsDepth() && deduced_dst.IsDepth())) {
+                return;
+            }
+        } else {
+            if (incomplete_src && !(deduced_dst.IsDepth())) {
+                return;
+            }
+
+            if (incomplete_dst && !(deduced_src.IsDepth())) {
+                return;
+            }
+        }
+
+        const auto inherit_format = ([](SurfaceParams& to, TSurface from) {
+            const SurfaceParams& params = from->GetSurfaceParams();
+            to.pixel_format = params.pixel_format;
+            to.component_type = params.component_type;
+            to.type = params.type;
+        });
+        // Now we got the cases where one or both is Depth and the other is not known
+        if (!incomplete_src) {
+            inherit_format(src_params, deduced_src.surface);
+        } else {
+            inherit_format(src_params, deduced_dst.surface);
+        }
+        if (!incomplete_dst) {
+            inherit_format(dst_params, deduced_dst.surface);
+        } else {
+            inherit_format(dst_params, deduced_src.surface);
+        }
+    }
+
     std::pair<TSurface, TView> InitializeSurface(GPUVAddr gpu_addr, const SurfaceParams& params,
                                                  bool preserve_contents) {
         auto new_surface{GetUncachedSurface(gpu_addr, params)};

src/yuzu/CMakeLists.txt

@@ -66,6 +66,9 @@ add_executable(yuzu
     configuration/configure_profile_manager.cpp
     configuration/configure_profile_manager.h
     configuration/configure_profile_manager.ui
+    configuration/configure_service.cpp
+    configuration/configure_service.h
+    configuration/configure_service.ui
     configuration/configure_system.cpp
     configuration/configure_system.h
     configuration/configure_system.ui
@@ -186,6 +189,10 @@ if (YUZU_USE_QT_WEB_ENGINE)
     target_compile_definitions(yuzu PRIVATE -DYUZU_USE_QT_WEB_ENGINE)
 endif ()
 
+if (YUZU_ENABLE_BOXCAT)
+    target_compile_definitions(yuzu PRIVATE -DYUZU_ENABLE_BOXCAT)
+endif ()
+
 if(UNIX AND NOT APPLE)
     install(TARGETS yuzu RUNTIME DESTINATION "${CMAKE_INSTALL_PREFIX}/bin")
 endif()

src/yuzu/configuration/config.cpp

@@ -525,6 +525,17 @@ void Config::ReadDebuggingValues() {
     qt_config->endGroup();
 }
 
+void Config::ReadServiceValues() {
+    qt_config->beginGroup(QStringLiteral("Services"));
+    Settings::values.bcat_backend =
+        ReadSetting(QStringLiteral("bcat_backend"), QStringLiteral("boxcat"))
+            .toString()
+            .toStdString();
+    Settings::values.bcat_boxcat_local =
+        ReadSetting(QStringLiteral("bcat_boxcat_local"), false).toBool();
+    qt_config->endGroup();
+}
+
 void Config::ReadDisabledAddOnValues() {
     const auto size = qt_config->beginReadArray(QStringLiteral("DisabledAddOns"));
 
@@ -769,6 +780,7 @@ void Config::ReadValues() {
     ReadMiscellaneousValues();
     ReadDebuggingValues();
     ReadWebServiceValues();
+    ReadServiceValues();
     ReadDisabledAddOnValues();
     ReadUIValues();
 }
@@ -866,6 +878,7 @@ void Config::SaveValues() {
     SaveMiscellaneousValues();
     SaveDebuggingValues();
     SaveWebServiceValues();
+    SaveServiceValues();
     SaveDisabledAddOnValues();
     SaveUIValues();
 }
@@ -963,6 +976,14 @@ void Config::SaveDebuggingValues() {
     qt_config->endGroup();
 }
 
+void Config::SaveServiceValues() {
+    qt_config->beginGroup(QStringLiteral("Services"));
+    WriteSetting(QStringLiteral("bcat_backend"),
+                 QString::fromStdString(Settings::values.bcat_backend), QStringLiteral("null"));
+    WriteSetting(QStringLiteral("bcat_boxcat_local"), Settings::values.bcat_boxcat_local, false);
+    qt_config->endGroup();
+}
+
 void Config::SaveDisabledAddOnValues() {
     qt_config->beginWriteArray(QStringLiteral("DisabledAddOns"));
 

src/yuzu/configuration/config.h

@@ -42,6 +42,7 @@ private:
     void ReadCoreValues();
     void ReadDataStorageValues();
     void ReadDebuggingValues();
+    void ReadServiceValues();
     void ReadDisabledAddOnValues();
     void ReadMiscellaneousValues();
     void ReadPathValues();
@@ -65,6 +66,7 @@ private:
     void SaveCoreValues();
     void SaveDataStorageValues();
     void SaveDebuggingValues();
+    void SaveServiceValues();
     void SaveDisabledAddOnValues();
     void SaveMiscellaneousValues();
     void SavePathValues();

src/yuzu/configuration/configure.ui

@@ -98,6 +98,11 @@
          <string>Web</string>
         </attribute>
        </widget>
+       <widget class="ConfigureService" name="serviceTab">
+        <attribute name="title">
+         <string>Services</string>
+        </attribute>
+       </widget>
       </widget>
      </item>
     </layout>
@@ -178,6 +183,12 @@
    <header>configuration/configure_hotkeys.h</header>
    <container>1</container>
   </customwidget>
+  <customwidget>
+   <class>ConfigureService</class>
+   <extends>QWidget</extends>
+   <header>configuration/configure_service.h</header>
+   <container>1</container>
+  </customwidget>
  </customwidgets>
  <resources/>
  <connections>

src/yuzu/configuration/configure_dialog.cpp

@@ -44,6 +44,7 @@ void ConfigureDialog::ApplyConfiguration() {
     ui->audioTab->ApplyConfiguration();
     ui->debugTab->ApplyConfiguration();
     ui->webTab->ApplyConfiguration();
+    ui->serviceTab->ApplyConfiguration();
     Settings::Apply();
     Settings::LogSettings();
 }
@@ -74,7 +75,8 @@ Q_DECLARE_METATYPE(QList<QWidget*>);
 void ConfigureDialog::PopulateSelectionList() {
     const std::array<std::pair<QString, QList<QWidget*>>, 4> items{
         {{tr("General"), {ui->generalTab, ui->webTab, ui->debugTab, ui->gameListTab}},
-         {tr("System"), {ui->systemTab, ui->profileManagerTab, ui->filesystemTab, ui->audioTab}},
+         {tr("System"),
+          {ui->systemTab, ui->profileManagerTab, ui->serviceTab, ui->filesystemTab, ui->audioTab}},
          {tr("Graphics"), {ui->graphicsTab}},
          {tr("Controls"), {ui->inputTab, ui->hotkeysTab}}},
     };
@@ -108,6 +110,7 @@ void ConfigureDialog::UpdateVisibleTabs() {
         {ui->webTab, tr("Web")},
         {ui->gameListTab, tr("Game List")},
         {ui->filesystemTab, tr("Filesystem")},
+        {ui->serviceTab, tr("Services")},
     };
 
     [[maybe_unused]] const QSignalBlocker blocker(ui->tabWidget);

src/yuzu/configuration/configure_service.cpp

@@ -0,0 +1,138 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <QGraphicsItem>
+#include <QtConcurrent/QtConcurrent>
+#include "core/hle/service/bcat/backend/boxcat.h"
+#include "core/settings.h"
+#include "ui_configure_service.h"
+#include "yuzu/configuration/configure_service.h"
+
+namespace {
+QString FormatEventStatusString(const Service::BCAT::EventStatus& status) {
+    QString out;
+
+    if (status.header.has_value()) {
+        out += QStringLiteral("<i>%1</i><br>").arg(QString::fromStdString(*status.header));
+    }
+
+    if (status.events.size() == 1) {
+        out += QStringLiteral("%1<br>").arg(QString::fromStdString(status.events.front()));
+    } else {
+        for (const auto& event : status.events) {
+            out += QStringLiteral("- %1<br>").arg(QString::fromStdString(event));
+        }
+    }
+
+    if (status.footer.has_value()) {
+        out += QStringLiteral("<i>%1</i><br>").arg(QString::fromStdString(*status.footer));
+    }
+
+    return out;
+}
+} // Anonymous namespace
+
+ConfigureService::ConfigureService(QWidget* parent)
+    : QWidget(parent), ui(std::make_unique<Ui::ConfigureService>()) {
+    ui->setupUi(this);
+
+    ui->bcat_source->addItem(QStringLiteral("None"));
+    ui->bcat_empty_label->setHidden(true);
+    ui->bcat_empty_header->setHidden(true);
+
+#ifdef YUZU_ENABLE_BOXCAT
+    ui->bcat_source->addItem(QStringLiteral("Boxcat"), QStringLiteral("boxcat"));
+#endif
+
+    connect(ui->bcat_source, QOverload<int>::of(&QComboBox::currentIndexChanged), this,
+            &ConfigureService::OnBCATImplChanged);
+
+    this->SetConfiguration();
+}
+
+ConfigureService::~ConfigureService() = default;
+
+void ConfigureService::ApplyConfiguration() {
+    Settings::values.bcat_backend = ui->bcat_source->currentText().toLower().toStdString();
+}
+
+void ConfigureService::RetranslateUi() {
+    ui->retranslateUi(this);
+}
+
+void ConfigureService::SetConfiguration() {
+    const int index =
+        ui->bcat_source->findData(QString::fromStdString(Settings::values.bcat_backend));
+    ui->bcat_source->setCurrentIndex(index == -1 ? 0 : index);
+}
+
+std::pair<QString, QString> ConfigureService::BCATDownloadEvents() {
+    std::optional<std::string> global;
+    std::map<std::string, Service::BCAT::EventStatus> map;
+    const auto res = Service::BCAT::Boxcat::GetStatus(global, map);
+
+    switch (res) {
+    case Service::BCAT::Boxcat::StatusResult::Success:
+        break;
+    case Service::BCAT::Boxcat::StatusResult::Offline:
+        return {QString{},
+                tr("The boxcat service is offline or you are not connected to the internet.")};
+    case Service::BCAT::Boxcat::StatusResult::ParseError:
+        return {QString{},
+                tr("There was an error while processing the boxcat event data. Contact the yuzu "
+                   "developers.")};
+    case Service::BCAT::Boxcat::StatusResult::BadClientVersion:
+        return {QString{},
+                tr("The version of yuzu you are using is either too new or too old for the server. "
+                   "Try updating to the latest official release of yuzu.")};
+    }
+
+    if (map.empty()) {
+        return {QStringLiteral("Current Boxcat Events"),
+                tr("There are currently no events on boxcat.")};
+    }
+
+    QString out;
+
+    if (global.has_value()) {
+        out += QStringLiteral("%1<br>").arg(QString::fromStdString(*global));
+    }
+
+    for (const auto& [key, value] : map) {
+        out += QStringLiteral("%1<b>%2</b><br>%3")
+                   .arg(out.isEmpty() ? QString{} : QStringLiteral("<br>"))
+                   .arg(QString::fromStdString(key))
+                   .arg(FormatEventStatusString(value));
+    }
+    return {QStringLiteral("Current Boxcat Events"), std::move(out)};
+}
+
+void ConfigureService::OnBCATImplChanged() {
+#ifdef YUZU_ENABLE_BOXCAT
+    const auto boxcat = ui->bcat_source->currentText() == QStringLiteral("Boxcat");
+    ui->bcat_empty_header->setHidden(!boxcat);
+    ui->bcat_empty_label->setHidden(!boxcat);
+    ui->bcat_empty_header->setText(QString{});
+    ui->bcat_empty_label->setText(tr("Yuzu is retrieving the latest boxcat status..."));
+
+    if (!boxcat)
+        return;
+
+    const auto future = QtConcurrent::run([this] { return BCATDownloadEvents(); });
+
+    watcher.setFuture(future);
+    connect(&watcher, &QFutureWatcher<std::pair<QString, QString>>::finished, this,
+            [this] { OnUpdateBCATEmptyLabel(watcher.result()); });
+#endif
+}
+
+void ConfigureService::OnUpdateBCATEmptyLabel(std::pair<QString, QString> string) {
+#ifdef YUZU_ENABLE_BOXCAT
+    const auto boxcat = ui->bcat_source->currentText() == QStringLiteral("Boxcat");
+    if (boxcat) {
+        ui->bcat_empty_header->setText(string.first);
+        ui->bcat_empty_label->setText(string.second);
+    }
+#endif
+}

src/yuzu/configuration/configure_service.h

@@ -0,0 +1,34 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <QFutureWatcher>
+#include <QWidget>
+
+namespace Ui {
+class ConfigureService;
+}
+
+class ConfigureService : public QWidget {
+    Q_OBJECT
+
+public:
+    explicit ConfigureService(QWidget* parent = nullptr);
+    ~ConfigureService() override;
+
+    void ApplyConfiguration();
+    void RetranslateUi();
+
+private:
+    void SetConfiguration();
+
+    std::pair<QString, QString> BCATDownloadEvents();
+    void OnBCATImplChanged();
+    void OnUpdateBCATEmptyLabel(std::pair<QString, QString> string);
+
+    std::unique_ptr<Ui::ConfigureService> ui;
+    QFutureWatcher<std::pair<QString, QString>> watcher{this};
+};

src/yuzu/configuration/configure_service.ui

@@ -0,0 +1,124 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>ConfigureService</class>
+ <widget class="QWidget" name="ConfigureService">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>433</width>
+    <height>561</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <layout class="QVBoxLayout" name="verticalLayout_3">
+     <item>
+      <widget class="QGroupBox" name="groupBox">
+       <property name="title">
+        <string>BCAT</string>
+       </property>
+       <layout class="QGridLayout" name="gridLayout">
+        <item row="1" column="1" colspan="2">
+         <widget class="QLabel" name="label_2">
+          <property name="maximumSize">
+           <size>
+            <width>260</width>
+            <height>16777215</height>
+           </size>
+          </property>
+          <property name="text">
+           <string>BCAT is Nintendo's way of sending data to games to engage its community and unlock additional content.</string>
+          </property>
+          <property name="wordWrap">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="0">
+         <widget class="QLabel" name="label">
+          <property name="maximumSize">
+           <size>
+            <width>16777215</width>
+            <height>16777215</height>
+           </size>
+          </property>
+          <property name="text">
+           <string>BCAT Backend</string>
+          </property>
+         </widget>
+        </item>
+        <item row="3" column="1" colspan="2">
+         <widget class="QLabel" name="bcat_empty_label">
+          <property name="enabled">
+           <bool>true</bool>
+          </property>
+          <property name="maximumSize">
+           <size>
+            <width>260</width>
+            <height>16777215</height>
+           </size>
+          </property>
+          <property name="text">
+           <string/>
+          </property>
+          <property name="alignment">
+           <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignTop</set>
+          </property>
+          <property name="wordWrap">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+        <item row="2" column="1" colspan="2">
+         <widget class="QLabel" name="label_3">
+          <property name="text">
+           <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;&lt;a href=&quot;https://yuzu-emu.org/help/feature/boxcat&quot;&gt;&lt;span style=&quot; text-decoration: underline; color:#0000ff;&quot;&gt;Learn more about BCAT, Boxcat, and Current Events&lt;/span&gt;&lt;/a&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+          </property>
+          <property name="openExternalLinks">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="1" colspan="2">
+         <widget class="QComboBox" name="bcat_source"/>
+        </item>
+        <item row="3" column="0">
+         <widget class="QLabel" name="bcat_empty_header">
+          <property name="text">
+           <string/>
+          </property>
+          <property name="alignment">
+           <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignTop</set>
+          </property>
+          <property name="wordWrap">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <spacer name="verticalSpacer">
+     <property name="orientation">
+      <enum>Qt::Vertical</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>20</width>
+       <height>40</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>