adding spirv header parsing

Author: Kbz-8

src/Module.zig

@@ -1,5 +1,6 @@
 const std = @import("std");
 const lib = @import("lib.zig");
+const spv_data = @import("spv_data.zig");
 
 const SpvVoid = lib.SpvVoid;
 const SpvByte = lib.SpvByte;
@@ -20,13 +21,21 @@ const SpvEntryPoint = struct {
     globals: []const SpvWord,
 };
 
+const ModuleError = error{
+    InvalidSpirV,
+    InvalidMagic,
+    OutOfMemory,
+};
+
 ctx: *const Interpreter,
 
 it: WordIterator,
 
 version_major: SpvByte,
 version_minor: SpvByte,
-generator_magic: SpvWord,
+
+generator_id: u16,
+generator_version: u16,
 
 bound: SpvWord,
 
@@ -42,14 +51,45 @@ local_size_x: SpvWord,
 local_size_y: SpvWord,
 local_size_z: SpvWord,
 
-pub fn init(allocator: std.mem.Allocator, ctx: *const Interpreter, source: []const SpvWord) !Self {
+pub fn init(allocator: std.mem.Allocator, ctx: *const Interpreter, source: []const SpvWord) ModuleError!Self {
     var self: Self = std.mem.zeroInit(Self, .{
         .ctx = ctx,
-        .code = try allocator.dupe(SpvWord, source),
+        .code = allocator.dupe(SpvWord, source) catch return ModuleError.OutOfMemory,
+        .local_size_x = 1,
+        .local_size_y = 1,
+        .local_size_z = 1,
     });
+    errdefer allocator.free(self.code);
 
     self.it = WordIterator.init(self.code);
 
+    const magic = self.it.next() orelse return ModuleError.InvalidSpirV;
+    if (magic != lib.spv.SpvMagicNumber) return ModuleError.InvalidMagic;
+
+    const version = self.it.next() orelse return ModuleError.InvalidSpirV;
+    self.version_major = @intCast((version & 0x00FF0000) >> 16);
+    self.version_minor = @intCast((version & 0x0000FF00) >> 8);
+
+    const generator = self.it.next() orelse return ModuleError.InvalidSpirV;
+    self.generator_id = @intCast((generator & 0xFFFF0000) >> 16);
+    self.generator_version = @intCast(generator & 0x0000FFFF);
+
+    self.bound = self.it.next() orelse return ModuleError.InvalidSpirV;
+
+    _ = self.it.skip(); // Skip schema
+
+    std.log.scoped(.SPIRV_Interpreter).debug(
+        \\Loaded shader module with infos:
+        \\    SPIR-V version: {d}.{d}
+        \\    Generator:      {s} (ID {d}), encoded version {d}
+    , .{
+        self.version_major,
+        self.version_minor,
+        spv_data.vendorName(self.generator_id),
+        self.generator_id,
+        self.generator_version,
+    });
+
     return self;
 }
 

src/lib.zig

@@ -5,7 +5,9 @@ pub const Image = @import("Image.zig");
 pub const Interpreter = @import("Interpreter.zig");
 pub const Module = @import("Module.zig");
 pub const State = @import("State.zig");
+
 const opcode = @import("opcode.zig");
+const spv_data = @import("spv_data.zig");
 
 pub const SpvVoid = void;
 pub const SpvByte = u8;
@@ -18,4 +20,5 @@ test {
     std.testing.refAllDecls(Module);
     std.testing.refAllDecls(State);
     std.testing.refAllDecls(opcode);
+    std.testing.refAllDecls(spv_data);
 }

src/spv_data.zig

@@ -0,0 +1,76 @@
+const lib = @import("lib.zig");
+const spv = lib.spv;
+
+pub const SourceLanguage = enum(u32) {
+    Unknown = 0,
+    ESSL = 1,
+    GLSL = 2,
+    OpenCL_C = 3,
+    OpenCL_CPP = 4,
+    HLSL = 5,
+    CPP_for_OpenCL = 6,
+    SYCL = 7,
+    HERO_C = 8,
+    NZSL = 9,
+    WGSL = 10,
+    Slang = 11,
+    Zig = 12,
+    Rust = 13,
+};
+
+pub fn vendorName(id: u32) []const u8 {
+    return switch (id) {
+        0 => "Khronos",
+        1 => "LunarG",
+        2 => "Valve",
+        3 => "Codeplay",
+        4 => "NVIDIA",
+        5 => "ARM",
+        6 => "Khronos LLVM/SPIR-V Translator",
+        7 => "Khronos SPIR-V Tools Assembler",
+        8 => "Khronos Glslang Reference Front End",
+        9 => "Qualcomm",
+        10 => "AMD",
+        11 => "Intel",
+        12 => "Imagination",
+        13 => "Google Shaderc over Glslang",
+        14 => "Google spiregg",
+        15 => "Google rspirv",
+        16 => "X-LEGEND Mesa-IR/SPIR-V Translator",
+        17 => "Khronos SPIR-V Tools Linker",
+        18 => "Wine VKD3D Shader Compiler",
+        19 => "Tellusim Clay Shader Compiler",
+        20 => "W3C WebGPU Group WHLSL Shader Translator",
+        21 => "Google Clspv",
+        22 => "LLVM MLIR SPIR-V Serializer",
+        23 => "Google Tint Compiler",
+        24 => "Google ANGLE Shader Compiler",
+        25 => "Netease Games Messiah Shader Compiler",
+        26 => "Xenia Xenia Emulator Microcode Translator",
+        27 => "Embark Studios Rust GPU Compiler Backend",
+        28 => "gfx-rs community Naga",
+        29 => "Mikkosoft Productions MSP Shader Compiler",
+        30 => "SpvGenTwo community SpvGenTwo SPIR-V IR Tools",
+        31 => "Google Skia SkSL",
+        32 => "TornadoVM Beehive SPIRV Toolkit",
+        33 => "DragonJoker ShaderWriter",
+        34 => "Rayan Hatout SPIRVSmith",
+        35 => "Saarland University Shady",
+        36 => "Taichi Graphics Taichi",
+        37 => "heroseh Hero C Compiler",
+        38 => "Meta SparkSL",
+        39 => "SirLynix Nazara ShaderLang Compiler",
+        40 => "Khronos Slang Compiler",
+        41 => "Zig Software Foundation Zig Compiler",
+        42 => "Rendong Liang spq",
+        43 => "LLVM LLVM SPIR-V Backend",
+        44 => "Robert Konrad Kongruent",
+        45 => "Kitsunebi Games Nuvk SPIR-V Emitter and DLSL compiler",
+        46 => "Nintendo",
+        47 => "ARM",
+        48 => "Goopax",
+        49 => "Icyllis Milica Arc3D Shader Compiler",
+
+        else => "Unknown",
+    };
+}