1 files changed, 90 insertions, 0 deletions
diff --git a/tools/spirv/grammar.zig b/tools/spirv/grammar.zig
new file mode 100644
index 0000000000..86a01641e4
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+++ b/tools/spirv/grammar.zig
@@ -0,0 +1,90 @@
+//! See https://www.khronos.org/registry/spir-v/specs/unified1/MachineReadableGrammar.html
+//! and the files in https://github.com/KhronosGroup/SPIRV-Headers/blob/master/include/spirv/unified1/
+//! Note: Non-canonical casing in these structs used to match SPIR-V spec json.
+pub const Registry = union(enum) {
+    core: CoreRegistry,
+    extension: ExtensionRegistry,
+};
+
+pub const CoreRegistry = struct {
+    copyright: [][]const u8,
+    /// Hexadecimal representation of the magic number
+    magic_number: []const u8,
+    major_version: u32,
+    minor_version: u32,
+    revision: u32,
+    instruction_printing_class: []InstructionPrintingClass,
+    instructions: []Instruction,
+    operand_kinds: []OperandKind,
+};
+
+pub const ExtensionRegistry = struct {
+    copyright: [][]const u8,
+    version: u32,
+    revision: u32,
+    instructions: []Instruction,
+    operand_kinds: []OperandKind = &[_]OperandKind{},
+};
+
+pub const InstructionPrintingClass = struct {
+    tag: []const u8,
+    heading: ?[]const u8 = null,
+};
+
+pub const Instruction = struct {
+    opname: []const u8,
+    class: ?[]const u8 = null, // Note: Only available in the core registry.
+    opcode: u32,
+    operands: []Operand = &[_]Operand{},
+    capabilities: [][]const u8 = &[_][]const u8{},
+    extensions: [][]const u8 = &[_][]const u8{},
+    version: ?[]const u8 = null,
+
+    lastVersion: ?[]const u8 = null,
+};
+
+pub const Operand = struct {
+    kind: []const u8,
+    /// If this field is 'null', the operand is only expected once.
+    quantifier: ?Quantifier = null,
+    name: []const u8 = "",
+};
+
+pub const Quantifier = enum {
+    /// zero or once
+    @"?",
+    /// zero or more
+    @"*",
+};
+
+pub const OperandCategory = enum {
+    BitEnum,
+    ValueEnum,
+    Id,
+    Literal,
+    Composite,
+};
+
+pub const OperandKind = struct {
+    category: OperandCategory,
+    /// The name
+    kind: []const u8,
+    doc: ?[]const u8 = null,
+    enumerants: ?[]Enumerant = null,
+    bases: ?[]const []const u8 = null,
+};
+
+pub const Enumerant = struct {
+    enumerant: []const u8,
+    value: union(enum) {
+        bitflag: []const u8, // Hexadecimal representation of the value
+        int: u31,
+    },
+    capabilities: [][]const u8 = &[_][]const u8{},
+    /// Valid for .ValueEnum and .BitEnum
+    extensions: [][]const u8 = &[_][]const u8{},
+    /// `quantifier` will always be `null`.
+    parameters: []Operand = &[_]Operand{},
+    version: ?[]const u8 = null,
+    lastVersion: ?[]const u8 = null,
+};