Vulkan: Use VK_NV_glsl extension where available, and skip glslang

Seems to produce faster ubershaders, at least.

Source/Core/VideoBackends/Vulkan/ShaderCompiler.cpp

@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include "VideoBackends/Vulkan/ShaderCompiler.h"
+#include "VideoBackends/Vulkan/VulkanContext.h"
 
 #include <cstddef>
 #include <cstdlib>
@@ -37,6 +38,11 @@ static bool CompileShaderToSPV(SPIRVCodeVector* out_code, EShLanguage stage,
                                const char* stage_filename, const char* source_code,
                                size_t source_code_length, const char* header, size_t header_length);
 
+// Copy GLSL source code to a SPIRVCodeVector, for use with VK_NV_glsl_shader.
+static void CopyGLSLToSPVVector(SPIRVCodeVector* out_code, const char* stage_filename,
+                                const char* source_code, size_t source_code_length,
+                                const char* header, size_t header_length);
+
 // Regarding the UBO bind points, we subtract one from the binding index because
 // the OpenGL backend requires UBO #0 for non-block uniforms (at least on NV).
 // This allows us to share the same shaders but use bind point #0 in the Vulkan
@@ -219,6 +225,42 @@ bool CompileShaderToSPV(SPIRVCodeVector* out_code, EShLanguage stage, const char
   return true;
 }
 
+void CopyGLSLToSPVVector(SPIRVCodeVector* out_code, const char* stage_filename,
+                         const char* source_code, size_t source_code_length, const char* header,
+                         size_t header_length)
+{
+  std::string full_source_code;
+  if (header_length > 0)
+  {
+    full_source_code.reserve(header_length + source_code_length);
+    full_source_code.append(header, header_length);
+    full_source_code.append(source_code, source_code_length);
+  }
+  else
+  {
+    full_source_code.append(source_code, source_code_length);
+  }
+
+  if (g_ActiveConfig.iLog & CONF_SAVESHADERS)
+  {
+    static int counter = 0;
+    std::string filename = StringFromFormat("%s%s_%04i.txt", File::GetUserPath(D_DUMP_IDX).c_str(),
+                                            stage_filename, counter++);
+
+    std::ofstream stream;
+    File::OpenFStream(stream, filename, std::ios_base::out);
+    if (stream.good())
+      stream << full_source_code << std::endl;
+  }
+
+  size_t padding = full_source_code.size() % 4;
+  if (padding != 0)
+    full_source_code.append(4 - padding, '\n');
+
+  out_code->resize(full_source_code.size() / 4);
+  std::memcpy(out_code->data(), full_source_code.c_str(), full_source_code.size());
+}
+
 bool InitializeGlslang()
 {
   static bool glslang_initialized = false;
@@ -338,29 +380,57 @@ const TBuiltInResource* GetCompilerResourceLimits()
 }
 
 bool CompileVertexShader(SPIRVCodeVector* out_code, const char* source_code,
-                         size_t source_code_length, bool prepend_header)
+                         size_t source_code_length)
 {
+  if (g_vulkan_context->SupportsNVGLSLExtension())
+  {
+    CopyGLSLToSPVVector(out_code, "vs", source_code, source_code_length, SHADER_HEADER,
+                        sizeof(SHADER_HEADER) - 1);
+    return true;
+  }
+
   return CompileShaderToSPV(out_code, EShLangVertex, "vs", source_code, source_code_length,
                             SHADER_HEADER, sizeof(SHADER_HEADER) - 1);
 }
 
 bool CompileGeometryShader(SPIRVCodeVector* out_code, const char* source_code,
-                           size_t source_code_length, bool prepend_header)
+                           size_t source_code_length)
 {
+  if (g_vulkan_context->SupportsNVGLSLExtension())
+  {
+    CopyGLSLToSPVVector(out_code, "gs", source_code, source_code_length, SHADER_HEADER,
+                        sizeof(SHADER_HEADER) - 1);
+    return true;
+  }
+
   return CompileShaderToSPV(out_code, EShLangGeometry, "gs", source_code, source_code_length,
                             SHADER_HEADER, sizeof(SHADER_HEADER) - 1);
 }
 
 bool CompileFragmentShader(SPIRVCodeVector* out_code, const char* source_code,
-                           size_t source_code_length, bool prepend_header)
+                           size_t source_code_length)
 {
+  if (g_vulkan_context->SupportsNVGLSLExtension())
+  {
+    CopyGLSLToSPVVector(out_code, "ps", source_code, source_code_length, SHADER_HEADER,
+                        sizeof(SHADER_HEADER) - 1);
+    return true;
+  }
+
   return CompileShaderToSPV(out_code, EShLangFragment, "ps", source_code, source_code_length,
                             SHADER_HEADER, sizeof(SHADER_HEADER) - 1);
 }
 
 bool CompileComputeShader(SPIRVCodeVector* out_code, const char* source_code,
-                          size_t source_code_length, bool prepend_header)
+                          size_t source_code_length)
 {
+  if (g_vulkan_context->SupportsNVGLSLExtension())
+  {
+    CopyGLSLToSPVVector(out_code, "cs", source_code, source_code_length, COMPUTE_SHADER_HEADER,
+                        sizeof(COMPUTE_SHADER_HEADER) - 1);
+    return true;
+  }
+
   return CompileShaderToSPV(out_code, EShLangCompute, "cs", source_code, source_code_length,
                             COMPUTE_SHADER_HEADER, sizeof(COMPUTE_SHADER_HEADER) - 1);
 }

Source/Core/VideoBackends/Vulkan/ShaderCompiler.h

@@ -19,19 +19,19 @@ using SPIRVCodeVector = std::vector<SPIRVCodeType>;
 
 // Compile a vertex shader to SPIR-V.
 bool CompileVertexShader(SPIRVCodeVector* out_code, const char* source_code,
-                         size_t source_code_length, bool prepend_header = true);
+                         size_t source_code_length);
 
 // Compile a geometry shader to SPIR-V.
 bool CompileGeometryShader(SPIRVCodeVector* out_code, const char* source_code,
-                           size_t source_code_length, bool prepend_header = true);
+                           size_t source_code_length);
 
 // Compile a fragment shader to SPIR-V.
 bool CompileFragmentShader(SPIRVCodeVector* out_code, const char* source_code,
-                           size_t source_code_length, bool prepend_header = true);
+                           size_t source_code_length);
 
 // Compile a compute shader to SPIR-V.
 bool CompileComputeShader(SPIRVCodeVector* out_code, const char* source_code,
-                          size_t source_code_length, bool prepend_header = true);
+                          size_t source_code_length);
 
 }  // namespace ShaderCompiler
 }  // namespace Vulkan

Source/Core/VideoBackends/Vulkan/TextureConverter.cpp

@@ -408,7 +408,7 @@ bool TextureConverter::SupportsTextureDecoding(TextureFormat format, TlutFormat
   std::string shader_source =
       TextureConversionShader::GenerateDecodingShader(format, palette_format, APIType::Vulkan);
 
-  pipeline.compute_shader = Util::CompileAndCreateComputeShader(shader_source, true);
+  pipeline.compute_shader = Util::CompileAndCreateComputeShader(shader_source);
   if (pipeline.compute_shader == VK_NULL_HANDLE)
   {
     m_decoding_pipelines.emplace(key, pipeline);

Source/Core/VideoBackends/Vulkan/Util.cpp

@@ -275,50 +275,38 @@ VkShaderModule CreateShaderModule(const u32* spv, size_t spv_word_count)
   return module;
 }
 
-VkShaderModule CompileAndCreateVertexShader(const std::string& source_code, bool prepend_header)
+VkShaderModule CompileAndCreateVertexShader(const std::string& source_code)
 {
   ShaderCompiler::SPIRVCodeVector code;
-  if (!ShaderCompiler::CompileVertexShader(&code, source_code.c_str(), source_code.length(),
+  if (!ShaderCompiler::CompileVertexShader(&code, source_code.c_str(), source_code.length()))
-                                           prepend_header))
-  {
     return VK_NULL_HANDLE;
-  }
 
   return CreateShaderModule(code.data(), code.size());
 }
 
-VkShaderModule CompileAndCreateGeometryShader(const std::string& source_code, bool prepend_header)
+VkShaderModule CompileAndCreateGeometryShader(const std::string& source_code)
 {
   ShaderCompiler::SPIRVCodeVector code;
-  if (!ShaderCompiler::CompileGeometryShader(&code, source_code.c_str(), source_code.length(),
+  if (!ShaderCompiler::CompileGeometryShader(&code, source_code.c_str(), source_code.length()))
-                                             prepend_header))
-  {
     return VK_NULL_HANDLE;
-  }
 
   return CreateShaderModule(code.data(), code.size());
 }
 
-VkShaderModule CompileAndCreateFragmentShader(const std::string& source_code, bool prepend_header)
+VkShaderModule CompileAndCreateFragmentShader(const std::string& source_code)
 {
   ShaderCompiler::SPIRVCodeVector code;
-  if (!ShaderCompiler::CompileFragmentShader(&code, source_code.c_str(), source_code.length(),
+  if (!ShaderCompiler::CompileFragmentShader(&code, source_code.c_str(), source_code.length()))
-                                             prepend_header))
-  {
     return VK_NULL_HANDLE;
-  }
 
   return CreateShaderModule(code.data(), code.size());
 }
 
-VkShaderModule CompileAndCreateComputeShader(const std::string& source_code, bool prepend_header)
+VkShaderModule CompileAndCreateComputeShader(const std::string& source_code)
 {
   ShaderCompiler::SPIRVCodeVector code;
-  if (!ShaderCompiler::CompileComputeShader(&code, source_code.c_str(), source_code.length(),
+  if (!ShaderCompiler::CompileComputeShader(&code, source_code.c_str(), source_code.length()))
-                                            prepend_header))
-  {
     return VK_NULL_HANDLE;
-  }
 
   return CreateShaderModule(code.data(), code.size());
 }

Source/Core/VideoBackends/Vulkan/Util.h

@@ -61,20 +61,16 @@ void ExecuteCurrentCommandsAndRestoreState(bool execute_off_thread,
 VkShaderModule CreateShaderModule(const u32* spv, size_t spv_word_count);
 
 // Compile a vertex shader and create a shader module, discarding the intermediate SPIR-V.
-VkShaderModule CompileAndCreateVertexShader(const std::string& source_code,
+VkShaderModule CompileAndCreateVertexShader(const std::string& source_code);
-                                            bool prepend_header = true);
 
 // Compile a geometry shader and create a shader module, discarding the intermediate SPIR-V.
-VkShaderModule CompileAndCreateGeometryShader(const std::string& source_code,
+VkShaderModule CompileAndCreateGeometryShader(const std::string& source_code);
-                                              bool prepend_header = true);
 
 // Compile a fragment shader and create a shader module, discarding the intermediate SPIR-V.
-VkShaderModule CompileAndCreateFragmentShader(const std::string& source_code,
+VkShaderModule CompileAndCreateFragmentShader(const std::string& source_code);
-                                              bool prepend_header = true);
 
 // Compile a compute shader and create a shader module, discarding the intermediate SPIR-V.
-VkShaderModule CompileAndCreateComputeShader(const std::string& source_code,
+VkShaderModule CompileAndCreateComputeShader(const std::string& source_code);
-                                             bool prepend_header = true);
 }
 
 // Utility shader vertex format

Source/Core/VideoBackends/Vulkan/VulkanContext.cpp

@@ -397,7 +397,8 @@ bool VulkanContext::SelectDeviceExtensions(ExtensionList* extension_list, bool e
   for (const auto& extension_properties : available_extension_list)
     INFO_LOG(VIDEO, "Available extension: %s", extension_properties.extensionName);
 
-  auto CheckForExtension = [&](const char* name, bool required) -> bool {
+  auto CheckForExtension = [&](const char* name, bool required,
+                               bool* has_extension = nullptr) -> bool {
     if (std::find_if(available_extension_list.begin(), available_extension_list.end(),
                      [&](const VkExtensionProperties& properties) {
                        return !strcmp(name, properties.extensionName);
@@ -405,9 +406,14 @@ bool VulkanContext::SelectDeviceExtensions(ExtensionList* extension_list, bool e
     {
       INFO_LOG(VIDEO, "Enabling extension: %s", name);
       extension_list->push_back(name);
+      if (has_extension)
+        *has_extension = true;
       return true;
     }
 
+    if (has_extension)
+      *has_extension = false;
+
     if (required)
     {
       ERROR_LOG(VIDEO, "Vulkan: Missing required extension %s.", name);
@@ -420,6 +426,7 @@ bool VulkanContext::SelectDeviceExtensions(ExtensionList* extension_list, bool e
   if (enable_surface && !CheckForExtension(VK_KHR_SWAPCHAIN_EXTENSION_NAME, true))
     return false;
 
+  CheckForExtension(VK_NV_GLSL_SHADER_EXTENSION_NAME, false, &m_supports_nv_glsl_extension);
   return true;
 }
 

Source/Core/VideoBackends/Vulkan/VulkanContext.h

@@ -81,6 +81,7 @@ public:
   {
     return m_device_features.occlusionQueryPrecise == VK_TRUE;
   }
+  bool SupportsNVGLSLExtension() const { return m_supports_nv_glsl_extension; }
   // Helpers for getting constants
   VkDeviceSize GetUniformBufferAlignment() const
   {
@@ -125,6 +126,8 @@ private:
   VkPhysicalDeviceFeatures m_device_features = {};
   VkPhysicalDeviceProperties m_device_properties = {};
   VkPhysicalDeviceMemoryProperties m_device_memory_properties = {};
+
+  bool m_supports_nv_glsl_extension = false;
 };
 
 extern std::unique_ptr<VulkanContext> g_vulkan_context;