vulkan/slang: Allow a cache for spv.

gtk/src/gtk_config.cpp

@@ -22,6 +22,26 @@
 
 namespace fs = std::filesystem;
 
+std::string get_cache_dir()
+{
+    char *env_home = getenv("HOME");
+    char *env_cache = getenv("XDG_CACHE_HOME");
+
+    std::string dir;
+
+    if (env_cache)
+        dir = std::string(env_cache) + "/snes9x";
+
+    else if (env_home)
+        dir = std::string(env_home) + "/.cache/snes9x";
+
+    if (dir.empty())
+        return dir;
+
+    fs::create_directories(dir);
+    return dir;
+}
+
 std::string get_config_dir()
 {
     // Find config directory

gtk/src/gtk_config.h

@@ -159,6 +159,7 @@ class Snes9xConfig
     int joystick_threshold;
 };
 
+std::string get_cache_dir();
 std::string get_config_dir();
 std::string get_config_file_name();
 

gtk/src/gtk_display_driver_vulkan.cpp

@@ -84,7 +84,7 @@ int S9xVulkanDisplayDriver::init()
     if (!gui_config->shader_filename.empty() && gui_config->use_shaders)
     {
         shaderchain = std::make_unique<Vulkan::ShaderChain>(context.get());
-        if (!shaderchain->load_shader_preset(gui_config->shader_filename))
+        if (!shaderchain->load_shader_preset(gui_config->shader_filename, get_cache_dir()))
         {
             fmt::print("Couldn't load shader preset file\n");
             shaderchain = nullptr;
@@ -94,6 +94,8 @@ int S9xVulkanDisplayDriver::init()
             window->enable_widget("shader_parameters_item", true);
             return 0;
         }
+
+
     }
 
     simple_output = std::make_unique<Vulkan::SimpleOutput>(context.get(), vk::Format::eR5G6B5UnormPack16);

vulkan/slang_preset.cpp

@@ -107,6 +107,10 @@ bool SlangPreset::load_preset_file(string filename)
         }
     }
 
+    if (!cache_directory.empty())
+        for (auto &p : passes)
+            p.set_cache_directory(cache_directory);
+
     std::vector<std::future<bool>> futures;
     for (size_t i = 0; i < passes.size(); i++)
     {
@@ -135,6 +139,11 @@ bool SlangPreset::load_preset_file(string filename)
     return true;
 }
 
+void SlangPreset::set_cache_directory(std::string filename)
+{
+    cache_directory = filename;
+}
+
 /*
     Aggregates the parameters from individual stages and separate shader files,
     resolving duplicates.

vulkan/slang_preset.hpp

@@ -18,6 +18,7 @@ struct SlangPreset
     bool match_sampler_semantic(const std::string &name, int pass, SlangShader::Sampler::Type &type, int &specifier);
     void gather_parameters();
     bool save_to_file(std::string filename);
+    void set_cache_directory(std::string filename);
 
     struct Texture
     {
@@ -34,4 +35,5 @@ struct SlangPreset
     int oldest_previous_frame;
     bool uses_feedback;
     bool last_pass_uses_feedback;
+    std::string cache_directory;
 };

vulkan/slang_shader.cpp

@@ -10,6 +10,8 @@
 #include "../external/glslang/glslang/Public/ShaderLang.h"
 #include "../external/glslang/SPIRV/GlslangToSpv.h"
 #include "../external/glslang/StandAlone/ResourceLimits.h"
+#include "../external/xxh64/xxh64.hpp"
+#include <filesystem>
 
 using std::string;
 using std::vector;
@@ -23,6 +25,11 @@ SlangShader::~SlangShader()
 {
 }
 
+void SlangShader::set_cache_directory(std::string dir)
+{
+    cache_directory = dir;
+}
+
 /*
     Recursively load shader file and included files into memory, applying
     #include and #pragma directives. Will strip all directives except
@@ -231,44 +238,76 @@ std::vector<uint32_t> SlangShader::generate_spirv(std::string shader_string, std
 
 }
 
+std::string SlangShader::get_hash_filename(const std::string &shader_string)
+{
+    uint64_t hash = xxh64::hash(shader_string.c_str(), fragment_shader_string.size(), 56);
+    char hash_hex_string[32];
+    snprintf(hash_hex_string, 32, "%016lx.spv", hash);
+    auto cache_path = std::filesystem::path(cache_directory);
+    cache_path /= hash_hex_string;
+
+    return cache_path.string();
+}
+
+static const char *header = "SPVCACHE1";
+static size_t header_size = 9;
+
+bool SlangShader::load_cache(std::string hash_filename, std::vector<uint32_t> &output)
+{
+    if (cache_directory.empty())
+        return false;
+    if (!std::filesystem::exists(hash_filename))
+        return false;
+    auto size = std::filesystem::file_size(hash_filename);
+    size -= header_size;
+    if ((size & 3) != 0)
+        return false;
+
+    std::ifstream file(hash_filename, std::ios::binary);
+    char headerblock[header_size];
+    file.read(headerblock, header_size);
+    if (memcmp(headerblock, header, header_size))
+    {
+        printf("Invalid cache file format %s.\n", headerblock);
+        return false;
+    }
+
+    output.resize(size / 4);
+    file.read((char *)output.data(), size);
+
+    return true;
+}
+
+void SlangShader::save_cache(std::string hash_filename, std::vector<uint32_t> &spv)
+{
+    if (cache_directory.empty())
+        return;
+    std::ofstream file(hash_filename, std::ios::binary);
+    file.write(header, header_size);
+    file.write((char *)spv.data(), spv.size() * 4);
+}
+
 /*
     Generate SPIRV from separate preprocessed fragment and vertex shaders.
     Must have called divide_into_stages beforehand. Returns true on success.
 */
 bool SlangShader::generate_spirv()
 {
-    Initializeglslang();
+    fragment_shader_spirv.clear();
+    vertex_shader_spirv.clear();
 
-    const EShMessages messages = (EShMessages)(EShMsgDefault | EShMsgVulkanRules | EShMsgSpvRules | EShMsgDebugInfo | EShMsgAST | EShMsgEnhanced);
-    auto forbid_includer = glslang::TShader::ForbidIncluder();
+    auto vertex_cache_filename = get_hash_filename(vertex_shader_string);
+    auto fragment_cache_filename = get_hash_filename(fragment_shader_string);
 
-    glslang::TShader vertexTShader(EShLangVertex);
-    glslang::TShader fragmentTShader(EShLangFragment);
-
-    auto compile = [&](glslang::TShader &shader, string &shader_string, std::vector<uint32_t> &spirv) -> bool {
-        const char *source = shader_string.c_str();
-        shader.setStrings(&source, 1);
-        if (!shader.parse(&glslang::DefaultTBuiltInResource, 450, false, messages, forbid_includer))
-            return false;
-
-        glslang::TProgram program;
-        program.addShader(&shader);
-        if (!program.link(messages))
-            return false;
-
-        glslang::GlslangToSpv(*program.getIntermediate(shader.getStage()), spirv);
+    if (load_cache(vertex_cache_filename, vertex_shader_spirv))
+        if (load_cache(fragment_cache_filename, fragment_shader_spirv))
             return true;
-    };
 
-    if (!compile(vertexTShader, vertex_shader_string, vertex_shader_spirv))
-    {
-        printf("%s\n%s\n", vertexTShader.getInfoLog(), vertexTShader.getInfoDebugLog());
-        return false;
-    }
-    if (!compile(fragmentTShader, fragment_shader_string, fragment_shader_spirv))
-    {
-        printf("%s\n%s\n", fragmentTShader.getInfoLog(), fragmentTShader.getInfoDebugLog());
-        return false;
-    }
+    vertex_shader_spirv = generate_spirv(vertex_shader_string, "vertex");
+    fragment_shader_spirv = generate_spirv(fragment_shader_string, "fragment");
+
+    save_cache(vertex_cache_filename, vertex_shader_spirv);
+    save_cache(fragment_cache_filename, fragment_shader_spirv);
+
     return true;
 }

vulkan/slang_shader.hpp

@@ -72,6 +72,10 @@ struct SlangShader
     bool load_file(std::string new_filename = "");
     void divide_into_stages(const std::vector<std::string> &lines);
     bool generate_spirv();
+    std::string get_hash_filename(const std::string &shader_string);
+    bool load_cache(std::string hash_filename, std::vector<uint32_t> &output);
+    void save_cache(std::string hash_filename, std::vector<uint32_t> &spv);
+    void set_cache_directory(std::string dir);
     static std::vector<uint32_t> generate_spirv(std::string shader_string, std::string stage);
 
     std::string filename;
@@ -100,4 +104,5 @@ struct SlangShader
     int ubo_binding;
     std::vector<Uniform> uniforms;
     std::vector<Sampler> samplers;
+    std::string cache_directory;
 };

vulkan/vulkan_shader_chain.cpp

@@ -187,13 +187,16 @@ void ShaderChain::update_and_propagate_sizes(int original_width_new, int origina
     }
 }
 
-bool ShaderChain::load_shader_preset(std::string filename)
+bool ShaderChain::load_shader_preset(std::string filename, std::string cache_dir)
 {
     if (!ends_with(filename, ".slangp"))
         printf("Warning: loading preset without .slangp extension\n");
 
     preset = std::make_unique<SlangPreset>();
 
+    if (!cache_dir.empty())
+        preset->set_cache_directory(cache_dir);
+
     if (!preset->load_preset_file(filename))
     {
         printf("Couldn't load preset file: %s\n", filename.c_str());

vulkan/vulkan_shader_chain.hpp

@@ -16,7 +16,7 @@ class ShaderChain
 
     ShaderChain(Context *context_);
     ~ShaderChain();
-    bool load_shader_preset(std::string filename);
+    bool load_shader_preset(std::string filename, std::string cache_dir = "");
     void update_and_propagate_sizes(int original_width_, int original_height_, int viewport_width_, int viewport_height_);
     bool load_lookup_textures();
     void do_frame(uint8_t *data, int width, int height, int stride, vk::Format format, int viewport_x, int viewport_y, int viewport_width, int viewport_height);