Add toggle to disable SPIRV optimization pass (#1080)

* Add toggle to disable SPIRV optimization pass

* vk_shader_util.cpp: Nitpicky comment tweak

* Consistently refer to "optimizer" instead of "optimization"

---------

Co-authored-by: OpenSauce04 <opensauce04@gmail.com>

src/android/app/src/main/java/org/citra/citra_emu/features/settings/model/BooleanSetting.kt

@@ -12,6 +12,7 @@ enum class BooleanSetting(
     EXPAND_TO_CUTOUT_AREA("expand_to_cutout_area", Settings.SECTION_LAYOUT, false),
     SPIRV_SHADER_GEN("spirv_shader_gen", Settings.SECTION_RENDERER, true),
     ASYNC_SHADERS("async_shader_compilation", Settings.SECTION_RENDERER, false),
+    DISABLE_SPIRV_OPTIMIZER("disable_spirv_optimizer", Settings.SECTION_RENDERER, true),
     PLUGIN_LOADER("plugin_loader", Settings.SECTION_SYSTEM, false),
     ALLOW_PLUGIN_LOADER("allow_plugin_loader", Settings.SECTION_SYSTEM, true),
     SWAP_SCREEN("swap_screen", Settings.SECTION_LAYOUT, false),

src/android/app/src/main/java/org/citra/citra_emu/features/settings/ui/SettingsFragmentPresenter.kt

@@ -839,6 +839,15 @@ class SettingsFragmentPresenter(private val fragmentView: SettingsFragmentView)
                     BooleanSetting.SPIRV_SHADER_GEN.defaultValue,
                 )
             )
+            add(
+                SwitchSetting(
+                    BooleanSetting.DISABLE_SPIRV_OPTIMIZER,
+                    R.string.disable_spirv_optimizer,
+                    R.string.disable_spirv_optimizer_description,
+                    BooleanSetting.DISABLE_SPIRV_OPTIMIZER.key,
+                    BooleanSetting.DISABLE_SPIRV_OPTIMIZER.defaultValue,
+                )
+            )
             add(
                 SwitchSetting(
                     BooleanSetting.ASYNC_SHADERS,

src/android/app/src/main/jni/config.cpp

@@ -142,6 +142,7 @@ void Config::ReadValues() {
     ReadSetting("Renderer", Settings::values.async_presentation);
     ReadSetting("Renderer", Settings::values.async_shader_compilation);
     ReadSetting("Renderer", Settings::values.spirv_shader_gen);
+    ReadSetting("Renderer", Settings::values.disable_spirv_optimizer);
     ReadSetting("Renderer", Settings::values.use_hw_shader);
     ReadSetting("Renderer", Settings::values.use_shader_jit);
     ReadSetting("Renderer", Settings::values.resolution_factor);

src/android/app/src/main/jni/default_ini.h

@@ -113,6 +113,10 @@ async_shader_compilation =
 # 0: GLSL, 1: SPIR-V (default)
 spirv_shader_gen =
 
+# Whether to disable the SPIRV optimizer. Disabling it reduces stutter, but may slightly worsen performance
+# 0: Enabled, 1: Disabled (default)
+disable_spirv_optimizer =
+
 # Whether to use hardware shaders to emulate 3DS shaders
 # 0: Software, 1 (default): Hardware
 use_hw_shader =

src/android/app/src/main/res/values/strings.xml

@@ -870,5 +870,7 @@
     <string name="emulation_quickload">Quickload</string>
     <string name="emulation_occupied_quicksave_slot">Quicksave - %1$tF %1$tR</string>
     <string name="quickload_not_found">No Quicksave available.</string>
+    <string name="disable_spirv_optimizer">Disable SPIR-V Optimizer</string>
+    <string name="disable_spirv_optimizer_description">Disables the SPIR-V optimization pass, reducing stuttering considerably while barely affecting performance.</string>
 
 </resources>

src/citra_qt/configuration/configure_graphics.cpp

@@ -1,4 +1,4 @@
-// Copyright 2016 Citra Emulator Project
+// Copyright Citra Emulator Project / Azahar Emulator Project
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
@@ -59,6 +59,7 @@ ConfigureGraphics::ConfigureGraphics(QString gl_renderer, std::span<const QStrin
 
         ui->physical_device_combo->setVisible(false);
         ui->spirv_shader_gen->setVisible(false);
+        ui->disable_spirv_optimizer->setVisible(false);
     } else {
         for (const QString& name : physical_devices) {
             ui->physical_device_combo->addItem(name);
@@ -143,6 +144,7 @@ void ConfigureGraphics::SetConfiguration() {
     ui->toggle_disk_shader_cache->setChecked(Settings::values.use_disk_shader_cache.GetValue());
     ui->toggle_vsync_new->setChecked(Settings::values.use_vsync_new.GetValue());
     ui->spirv_shader_gen->setChecked(Settings::values.spirv_shader_gen.GetValue());
+    ui->disable_spirv_optimizer->setChecked(Settings::values.disable_spirv_optimizer.GetValue());
     ui->toggle_async_shaders->setChecked(Settings::values.async_shader_compilation.GetValue());
     ui->toggle_async_present->setChecked(Settings::values.async_presentation.GetValue());
 
@@ -162,6 +164,8 @@ void ConfigureGraphics::ApplyConfiguration() {
                                              ui->toggle_async_present, async_presentation);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.spirv_shader_gen,
                                              ui->spirv_shader_gen, spirv_shader_gen);
+    ConfigurationShared::ApplyPerGameSetting(&Settings::values.disable_spirv_optimizer,
+                                             ui->disable_spirv_optimizer, disable_spirv_optimizer);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.use_hw_shader, ui->toggle_hw_shader,
                                              use_hw_shader);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.shaders_accurate_mul,
@@ -241,6 +245,9 @@ void ConfigureGraphics::SetupPerGameUI() {
         ui->toggle_async_present, Settings::values.async_presentation, async_presentation);
     ConfigurationShared::SetColoredTristate(ui->spirv_shader_gen, Settings::values.spirv_shader_gen,
                                             spirv_shader_gen);
+    ConfigurationShared::SetColoredTristate(ui->disable_spirv_optimizer,
+                                            Settings::values.disable_spirv_optimizer,
+                                            disable_spirv_optimizer);
 }
 
 void ConfigureGraphics::SetPhysicalDeviceComboVisibility(int index) {
@@ -263,5 +270,6 @@ void ConfigureGraphics::SetPhysicalDeviceComboVisibility(int index) {
 
     ui->physical_device_group->setVisible(effective_api == Settings::GraphicsAPI::Vulkan);
     ui->spirv_shader_gen->setVisible(effective_api == Settings::GraphicsAPI::Vulkan);
+    ui->disable_spirv_optimizer->setVisible(effective_api == Settings::GraphicsAPI::Vulkan);
     ui->opengl_renderer_group->setVisible(effective_api == Settings::GraphicsAPI::OpenGL);
 }

src/citra_qt/configuration/configure_graphics.h

@@ -1,4 +1,4 @@
-// Copyright 2016 Citra Emulator Project
+// Copyright Citra Emulator Project / Azahar Emulator Project
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
@@ -42,6 +42,7 @@ private:
     ConfigurationShared::CheckState async_shader_compilation;
     ConfigurationShared::CheckState async_presentation;
     ConfigurationShared::CheckState spirv_shader_gen;
+    ConfigurationShared::CheckState disable_spirv_optimizer;
     std::unique_ptr<Ui::ConfigureGraphics> ui;
     QColor bg_color;
 };

src/citra_qt/configuration/configure_graphics.ui

@@ -136,6 +136,16 @@
         </property>
        </widget>
       </item>
+      <item>
+       <widget class="QCheckBox" name="disable_spirv_optimizer">
+        <property name="text">
+         <string>Disable GLSL -> SPIR-V Optimizer</string>
+        </property>
+        <property name="toolTip">
+         <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Disables the SPIR-V optimization pass, reducing stuttering considerably while barely affecting performance.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+        </property>
+       </widget>
+      </item>
      </layout>
     </widget>
    </item>

src/common/settings.h

@@ -498,6 +498,7 @@ struct Values {
     Setting<bool> renderer_debug{false, "renderer_debug"};
     Setting<bool> dump_command_buffers{false, "dump_command_buffers"};
     SwitchableSetting<bool> spirv_shader_gen{true, "spirv_shader_gen"};
+    SwitchableSetting<bool> disable_spirv_optimizer{true, "disable_spirv_optimizer"};
     SwitchableSetting<bool> async_shader_compilation{false, "async_shader_compilation"};
     SwitchableSetting<bool> async_presentation{true, "async_presentation"};
     SwitchableSetting<bool> use_hw_shader{true, "use_hw_shader"};

src/video_core/renderer_vulkan/vk_shader_util.cpp

@@ -1,4 +1,4 @@
-// Copyright 2023 Citra Emulator Project
+// Copyright Citra Emulator Project / Azahar Emulator Project
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
@@ -9,6 +9,7 @@
 #include "common/assert.h"
 #include "common/literals.h"
 #include "common/logging/log.h"
+#include "common/settings.h"
 #include "video_core/renderer_vulkan/vk_shader_util.h"
 
 namespace Vulkan {
@@ -203,8 +204,8 @@ vk::ShaderModule Compile(std::string_view code, vk::ShaderStageFlagBits stage, v
     spv::SpvBuildLogger logger;
     glslang::SpvOptions options;
 
-    // Enable optimizations on the generated SPIR-V code.
+    // Controls optimizations on the generated SPIR-V code.
-    options.disableOptimizer = false;
+    options.disableOptimizer = Settings::values.disable_spirv_optimizer.GetValue();
     options.validate = false;
     options.optimizeSize = true;