[video_core] buffer cache readback for nce invalidations (#4490)

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

This is a follow up of 4473, a fix for the next Ender Magnolia known crash, the shackled beast's vaper crash, but specific for NCE.

Imma try to be short:

NCE invalidation was dooming whole guest pages when it shouldn't. If the GPU buffer cache owns some bytes on a page, invalidating first discards their ownership, and the retrying CPU can then observe stale data. On Android, this was corrupting some indirect draw packets and causing huge invalid index count reach staging memory allocation.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4490
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: lizzie <lizzie@eden-emu.dev>

cpmfile.json

@@ -333,6 +333,11 @@
         "repo": "herumi/xbyak",
         "version": "v7.40.1"
     },
+    "zbic": {
+        "hash": "fbe2f37986377d7f0d96ae3224c80b5971df6e8b6961f68061f1975ebb2e8cb78f07b90f014b007be4023dbf5513581504e7f7d61a5237cb2a8a7a61ae11e482",
+        "repo": "kinnay/zbic",
+        "version": "11b08f2712264bbed731545085cbd9702096ceb7"
+    },
     "zlib": {
         "hash": "16fea4df307a68cf0035858abe2fd550250618a97590e202037acd18a666f57afc10f8836cbbd472d54a0e76539d0e558cb26f059d53de52ff90634bbf4f47d4",
         "min_version": "1.2",

externals/CMakeLists.txt

@@ -48,6 +48,11 @@ if (NOT TARGET stb::headers)
     add_library(stb::headers ALIAS stb)
 endif()
 
+AddJsonPackage(NAME zbic DOWNLOAD_ONLY)
+set(ZBIC_INCLUDE_DIR
+    "${zbic_SOURCE_DIR}/src"
+    PARENT_SCOPE)
+
 # ItaniumDemangle (Windows only)
 if (WIN32 AND NOT TARGET LLVM::Demangle)
     add_library(demangle demangle/ItaniumDemangle.cpp)

src/common/CMakeLists.txt

@@ -137,6 +137,8 @@ add_library(
     uuid.cpp
     uuid.h
     vector_math.h
+    zbic_compression.cpp
+    zbic_compression.h
     zstd_compression.cpp
     zstd_compression.h
     fs/ryujinx_compat.h fs/ryujinx_compat.cpp
@@ -147,6 +149,10 @@ add_library(
     net/net.h net/net.cpp
     container/unordered_map.h container/unordered_set.h)
 
+set_source_files_properties(zbic_compression.cpp PROPERTIES
+    INCLUDE_DIRECTORIES "${ZBIC_INCLUDE_DIR}"
+    COMPILE_OPTIONS "$<$<CXX_COMPILER_ID:Clang,GNU>:-Wno-unused-function;-Wno-missing-declarations;-Wno-shadow>")
+
 if(WIN32)
     target_sources(common PRIVATE windows/timer_resolution.cpp
         windows/timer_resolution.h)

src/common/settings_enums.h

@@ -150,7 +150,7 @@ ENUM(ScalingFilter, NearestNeighbor, Bilinear, Bicubic, Gaussian, Lanczos, Scale
 ENUM(AntiAliasing, None, Fxaa, Smaa);
 ENUM(AspectRatio, R16_9, R4_3, R21_9, R16_10, Stretch);
 ENUM(ConsoleMode, Handheld, Docked);
-ENUM(AppletMode, HLE, LLE);
+ENUM(AppletMode, HLE, LLE, Disabled);
 ENUM(SpirvOptimizeMode, Never, OnLoad, Always);
 ENUM(GpuClock, Normal, Boost, Overclock)
 ENUM(GpuUnswizzleSize, VerySmall, Small, Normal, Large, VeryLarge)

src/common/zbic_compression.cpp

@@ -0,0 +1,46 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include <cstring>
+
+#include "common/zbic_compression.h"
+
+#define ZSTD_ZBIC_SUPPORT 1
+#define ZSTDLIB_VISIBLE static
+#define ZSTDLIB_HIDDEN static
+#define ZSTDERRORLIB_VISIBLE static
+#define ZSTDERRORLIB_HIDDEN static
+#undef ZSTD_MULTITHREAD
+
+#if defined(__ANDROID__)
+#undef _GNU_SOURCE
+#endif
+
+#include "zstd.h"
+#define g_ZSTD_threading_useless_symbol g_ZSTD_zbic_threading_useless_symbol
+#include "zstd.c"
+#undef g_ZSTD_threading_useless_symbol
+
+namespace Common::Compression {
+
+bool IsZBIC(std::span<const u8> src) {
+    if (src.size() < sizeof(u32)) {
+        return false;
+    }
+    u32 magic = 0;
+    std::memcpy(&magic, src.data(), sizeof(u32));
+    return magic == ZSTD_MAGICNUMBER; // 0x4349425A ("ZBIC")
+}
+
+int DecompressDataZBIC(std::span<u8> dst, std::span<const u8> src) {
+    if (dst.empty() || src.empty()) {
+        return -1;
+    }
+    const size_t res = ZSTD_decompress(dst.data(), dst.size(), src.data(), src.size());
+    if (ZSTD_isError(res)) {
+        return -1;
+    }
+    return static_cast<int>(res);
+}
+
+} // namespace Common::Compression

src/common/zbic_compression.h

@@ -0,0 +1,15 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <span>
+#include "common/common_types.h"
+
+namespace Common::Compression {
+
+[[nodiscard]] bool IsZBIC(std::span<const u8> src);
+
+[[nodiscard]] int DecompressDataZBIC(std::span<u8> dst, std::span<const u8> src);
+
+} // namespace Common::Compression

src/core/hle/service/ro/ro.cpp

@@ -16,6 +16,10 @@
 #include "core/hle/service/ro/ro_types.h"
 #include "core/hle/service/server_manager.h"
 #include "core/hle/service/service.h"
+#ifdef HAS_NCE
+#include "core/arm/nce/patcher.h"
+#include "core/hle/kernel/k_shared_memory.h"
+#endif
 
 namespace Service::RO {
 
@@ -386,7 +390,7 @@ public:
         R_SUCCEED();
     }
 
-    Result MapManualLoadModuleMemory(u64* out_address, size_t context_id, u64 nro_address,
+    Result MapManualLoadModuleMemory(Kernel::KernelCore& kernel, u64* out_address, size_t context_id, u64 nro_address,
                                      u64 nro_size, u64 bss_address, u64 bss_size) {
         // Get context.
         ProcessContext* context = this->GetContextById(context_id);
@@ -421,7 +425,31 @@ public:
         R_TRY(context->ValidateNro(std::addressof(nro_info->module_id), std::addressof(rx_size),
                                    std::addressof(ro_size), std::addressof(rw_size),
                                    nro_info->base_address, nro_size, bss_size));
+#ifdef HAS_NCE
+        if (Settings::IsNceEnabled()) {
+            auto* process = context->GetProcess();
+            auto& memory = process->GetMemory();
 
+            std::vector<u8> image(total_size);
+            memory.ReadBlock(nro_info->base_address, image.data(), rx_size);
+
+            Kernel::CodeSet::Segment code{.size = static_cast<u32>(rx_size)};
+            Core::NCE::Patcher patch;
+            patch.PatchText(image, code);
+            patch.RelocateAndCopy(nro_info->base_address, code, image, nullptr);
+
+            const u64 patch_address = nro_info->base_address + total_size;
+            const size_t patch_size = patch.GetSectionSize();
+            constexpr auto permission = Kernel::Svc::MemoryPermission::ReadExecute;
+
+            auto* patch_memory = Kernel::KSharedMemory::Create(kernel);
+            R_TRY(patch_memory->Initialize(kernel, kernel.System().DeviceMemory(), process, permission, permission, patch_size));
+            std::memcpy(patch_memory->GetPointer(), image.data() + total_size, patch_size);
+            R_TRY(process->AddSharedMemory(kernel, patch_memory, patch_address, patch_size));
+            R_TRY(patch_memory->Map(*process, patch_address, patch_size, permission));
+            memory.WriteBlock(nro_info->base_address, image.data(), rx_size);
+        }
+#endif
         // Set NRO perms.
         R_TRY(SetNroPerms(context->GetProcess(), nro_info->base_address, rx_size, ro_size,
                           rw_size + bss_size));
@@ -531,7 +559,7 @@ public:
     Result MapManualLoadModuleMemory(Out<u64> out_load_address, ClientProcessId client_pid,
                                      u64 nro_address, u64 nro_size, u64 bss_address, u64 bss_size) {
         R_TRY(m_ro->ValidateProcess(m_context_id, *client_pid));
-        R_RETURN(m_ro->MapManualLoadModuleMemory(out_load_address.Get(), m_context_id, nro_address,
+        R_RETURN(m_ro->MapManualLoadModuleMemory(system.Kernel(), out_load_address.Get(), m_context_id, nro_address,
                                                  nro_size, bss_address, bss_size));
     }
 

src/core/loader/nso.cpp

@@ -7,12 +7,14 @@
 #include <algorithm>
 #include <cinttypes>
 #include <cstring>
+#include <span>
 #include <vector>
 
 #include "common/common_funcs.h"
 #include "common/hex_util.h"
 #include "common/logging.h"
 #include "common/lz4_compression.h"
+#include "common/zbic_compression.h"
 #include "common/settings.h"
 #include "common/swap.h"
 #include "core/core.h"
@@ -104,11 +106,36 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(Kernel::KProcess& process, Core::
         for (std::size_t i = 0; i < nso_header.segments.size(); ++i) {
             nso_file.Read(compressed_data.data(), nso_header.segments_compressed_size[i], nso_header.segments[i].offset);
             if (nso_header.IsSegmentCompressed(i)) {
-                int r = Common::Compression::DecompressDataLZ4(decompressed_size.data(), nso_header.segments[i].size, compressed_data.data(), nso_header.segments_compressed_size[i]);
+                if (nso_header.IsZBICCompressed()) {
-                ASSERT(r == int(nso_header.segments[i].size));
+                    // ZBIC compression
-                std::memcpy(codeset.memory.data() + module_start + nso_header.segments[i].location, decompressed_size.data(), nso_header.segments[i].size);
+                    const int r = Common::Compression::DecompressDataZBIC(
+                        std::span<u8>{decompressed_size}.first(nso_header.segments[i].size),
+                        std::span<const u8>{compressed_data}.first(nso_header.segments_compressed_size[i])
+                    );
+                    ASSERT(r > 0);
                 } else {
-                std::memcpy(codeset.memory.data() + module_start + nso_header.segments[i].location, compressed_data.data(), nso_header.segments[i].size);
+                    // LZ4 compression
+                    int r = Common::Compression::DecompressDataLZ4(
+                        decompressed_size.data(),
+                        nso_header.segments[i].size,
+                        compressed_data.data(),
+                        nso_header.segments_compressed_size[i]
+                    );
+                    ASSERT(r == int(nso_header.segments[i].size));
+                }
+
+                std::memcpy(
+                    codeset.memory.data() + module_start + nso_header.segments[i].location,
+                    decompressed_size.data(),
+                    nso_header.segments[i].size
+                );
+            } else {
+                // Not compressed
+                std::memcpy(
+                    codeset.memory.data() + module_start + nso_header.segments[i].location,
+                    compressed_data.data(),
+                    nso_header.segments[i].size
+                );
             }
             codeset.segments[i].addr = module_start + nso_header.segments[i].location;
             codeset.segments[i].offset = module_start + nso_header.segments[i].location;

src/core/loader/nso.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -58,6 +61,9 @@ struct NSOHeader {
     std::array<SHA256Hash, 3> segment_hashes;
 
     bool IsSegmentCompressed(size_t segment_num) const;
+    bool IsZBICCompressed() const {
+        return ((flags >> 7) & 1) != 0;
+    }
 };
 static_assert(sizeof(NSOHeader) == 0x100, "NSOHeader has incorrect size.");
 static_assert(std::is_trivially_copyable_v<NSOHeader>, "NSOHeader must be trivially copyable.");

src/core/memory.cpp

@@ -757,7 +757,7 @@ struct Memory::Impl {
         };
         auto& gpu = system.GPU();
         gpu_device_memory->ApplyOpOnPointer(
-            p, scratch_buffers[core], [&](DAddr address) { gpu.InvalidateRegion(address, size); });
+            p, scratch_buffers[core], [&](DAddr address) { gpu.InvalidateRegion(address, size, true); });
     }
 
     Core::System& system;

src/qt_common/config/shared_translation.cpp

@@ -342,9 +342,6 @@ std::unique_ptr<TranslationMap> InitializeTranslations(QObject* parent) {
               "it bypasses such prompts and directly exits the emulation."));
     INSERT(UISettings, hide_mouse, tr("Hide mouse on inactivity"),
            tr("Hides the mouse after 2.5s of inactivity."));
-    INSERT(UISettings, controller_applet_disabled, tr("Disable controller applet"),
-           tr("Forcibly disables the use of the controller applet in emulated programs.\n"
-              "When a program attempts to open the controller applet, it is immediately closed."));
     INSERT(UISettings, check_for_updates, tr("Check for updates"),
            tr("Whether or not to check for updates upon startup."));
 
@@ -380,6 +377,7 @@ std::unique_ptr<ComboboxTranslationMap> ComboboxEnumeration(QObject* parent) {
                           {
                               PAIR(AppletMode, HLE, tr("Custom frontend")),
                               PAIR(AppletMode, LLE, tr("Real applet")),
+                              PAIR(AppletMode, Disabled, tr("Disabled")),
                           }});
 
     translations->insert({Settings::EnumMetadata<Settings::SpirvOptimizeMode>::Index(),

src/qt_common/config/uisettings.h

@@ -127,8 +127,6 @@ struct Values {
     Setting<bool> hide_mouse{
         linkage, true, "hideInactiveMouse", Category::UiGeneral, Settings::Specialization::Default,
         true,    true};
-    Setting<bool> controller_applet_disabled{linkage, false, "disableControllerApplet",
-                                             Category::UiGeneral};
     // Set when Vulkan is known to crash the application
     bool has_broken_vulkan = false;
 

src/video_core/gpu.cpp

@@ -226,7 +226,17 @@ struct GPU::Impl {
     }
 
     /// Notify rasterizer that any caches of the specified region should be invalidated
-    void InvalidateRegion(DAddr addr, u64 size) {
+    void InvalidateRegion(DAddr addr, u64 size, bool preserve_gpu_writes) {
+        VideoCore::RasterizerInterface* rasterizer = renderer->ReadRasterizer();
+        if (preserve_gpu_writes && rasterizer->MustFlushRegion(addr, size, VideoCommon::CacheType::BufferCache)) {
+            const u64 fence = RequestSyncOperation([rasterizer, addr, size] {
+                rasterizer->FlushRegion(addr, size, VideoCommon::CacheType::BufferCache);
+                rasterizer->OnCacheInvalidation(addr, size);
+            });
+            gpu_thread.TickGPU(is_async);
+            WaitForSyncOperation(fence);
+            return;
+        }
         gpu_thread.InvalidateRegion(addr, size);
     }
 
@@ -518,8 +528,8 @@ void GPU::FlushRegion(DAddr addr, u64 size) {
     impl->FlushRegion(addr, size);
 }
 
-void GPU::InvalidateRegion(DAddr addr, u64 size) {
+void GPU::InvalidateRegion(DAddr addr, u64 size, bool preserve_gpu_writes) {
-    impl->InvalidateRegion(addr, size);
+    impl->InvalidateRegion(addr, size, preserve_gpu_writes);
 }
 
 bool GPU::OnCPUWrite(DAddr addr, u64 size) {

src/video_core/gpu.h

@@ -248,7 +248,7 @@ public:
     void FlushRegion(DAddr addr, u64 size);
 
     /// Notify rasterizer that any caches of the specified region should be invalidated
-    void InvalidateRegion(DAddr addr, u64 size);
+    void InvalidateRegion(DAddr addr, u64 size, bool preserve_gpu_writes = false);
 
     /// Notify rasterizer that CPU is trying to write this area. It returns true if the area is
     /// sensible, false otherwise, addr and size must be a valid combination

src/yuzu/configuration/configure_applets.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -8,7 +11,6 @@
 
 class QCheckBox;
 class QLineEdit;
-class QComboBox;
 class QDateTimeEdit;
 namespace Core {
 class System;

src/yuzu/configuration/shared_widget.cpp

@@ -140,7 +140,12 @@ QWidget* Widget::CreateCombobox(std::function<std::string()>& serializer,
     if (combobox_enumerations.contains(type)) {
         enumeration = &combobox_enumerations.at(type);
         for (const auto& [id, name] : *enumeration) {
-            combobox->addItem(name);
+            if (type == Settings::EnumMetadata<Settings::AppletMode>::Index() &&
+                id == static_cast<u32>(Settings::AppletMode::Disabled) &&
+                setting.Id() != Settings::values.controller_applet_mode.Id()) {
+                continue;
+            }
+            combobox->addItem(name, id);
         }
     } else {
         return combobox;
@@ -158,9 +163,8 @@ QWidget* Widget::CreateCombobox(std::function<std::string()>& serializer,
     const u32 setting_value = std::strtoul(setting.ToString().c_str(), nullptr, 0);
     combobox->setCurrentIndex(find_index(setting_value));
 
-    serializer = [this, enumeration]() {
+    serializer = [this]() {
-        int current = combobox->currentIndex();
+        return std::to_string(combobox->currentData().toUInt());
-        return std::to_string(enumeration->at(current).first);
     };
 
     restore_func = [this, find_index]() {

src/yuzu/main_window.cpp

@@ -1786,7 +1786,7 @@ bool MainWindow::LoadROM(const QString& filename, Service::AM::FrontendAppletPar
 
     QtCommon::system->SetFrontendAppletSet({
         std::make_unique<QtAmiiboSettings>(*this), // Amiibo Settings
-        (UISettings::values.controller_applet_disabled.GetValue() == true)
+        (Settings::values.controller_applet_mode.GetValue() == Settings::AppletMode::Disabled)
             ? nullptr
             : std::make_unique<QtControllerSelector>(*this), // Controller Selector
         std::make_unique<QtErrorDisplay>(*this),             // Error Display