spirv: add zig-specific ext inst

This may be removed again in the future...

src/codegen/spirv/extinst.zig.grammar.json

@@ -0,0 +1,13 @@
+{
+    "version": 0,
+    "revision": 0,
+    "instructions": [
+        {
+            "opname": "InvocationGlobal",
+            "opcode": 0,
+            "operands": [
+                { "kind": "IdRef", "name": "initializer function" }
+            ]
+        }
+    ]
+}

src/codegen/spirv/spec.zig

@@ -102,6 +102,7 @@ pub const Class = enum {
 };
 
 pub const OperandKind = enum {
+    Opcode,
     ImageOperands,
     FPFastMathMode,
     SelectionControl,
@@ -187,6 +188,7 @@ pub const OperandKind = enum {
 
     pub fn category(self: OperandKind) OperandCategory {
         return switch (self) {
+            .Opcode => .literal,
             .ImageOperands => .bit_enum,
             .FPFastMathMode => .bit_enum,
             .SelectionControl => .bit_enum,
@@ -273,6 +275,7 @@ pub const OperandKind = enum {
     }
     pub fn enumerants(self: OperandKind) []const Enumerant {
         return switch (self) {
+            .Opcode => unreachable,
             .ImageOperands => &[_]Enumerant{
                 .{ .name = "Bias", .value = 0x0001, .parameters = &[_]OperandKind{.IdRef} },
                 .{ .name = "Lod", .value = 0x0002, .parameters = &[_]OperandKind{.IdRef} },
@@ -2104,7 +2107,6 @@ pub const Opcode = enum(u16) {
     OpGroupLogicalXorKHR = 6408,
     OpMaskedGatherINTEL = 6428,
     OpMaskedScatterINTEL = 6429,
-
     pub const OpSDotKHR = Opcode.OpSDot;
     pub const OpUDotKHR = Opcode.OpUDot;
     pub const OpSUDotKHR = Opcode.OpSUDot;
@@ -5278,6 +5280,7 @@ pub const InstructionSet = enum {
     @"nonsemantic.debugprintf",
     @"spv-amd-shader-explicit-vertex-parameter",
     @"nonsemantic.debugbreak",
+    zig,
 
     pub fn instructions(self: InstructionSet) []const Instruction {
         return switch (self) {
@@ -16505,6 +16508,15 @@ pub const InstructionSet = enum {
                     .operands = &[_]Operand{},
                 },
             },
+            .zig => &[_]Instruction{
+                .{
+                    .name = "InvocationGlobal",
+                    .opcode = 0,
+                    .operands = &[_]Operand{
+                        .{ .kind = .IdRef, .quantifier = .required },
+                    },
+                },
+            },
         };
     }
 };

tools/gen_spirv_spec.zig

@@ -48,16 +48,13 @@ pub fn main() !void {
     const a = arena.allocator();
 
     const args = try std.process.argsAlloc(a);
-    if (args.len != 2) {
+    if (args.len != 3) {
         usageAndExit(args[0], 1);
     }
 
     const json_path = try std.fs.path.join(a, &.{ args[1], "include/spirv/unified1/" });
     const dir = try std.fs.cwd().openDir(json_path, .{ .iterate = true });
 
-    // const spec_path = try std.fs.path.join(a, &.{spirv_headers_dir_path, "spirv.core.grammar.json"});
-    // const core_spec = try std.fs.cwd().readFileAlloc(a, spec_path, std.math.maxInt(usize));
-
     const core_spec = try readRegistry(CoreRegistry, a, dir, "spirv.core.grammar.json");
     std.sort.block(Instruction, core_spec.instructions, CmpInst{}, CmpInst.lt);
 
@@ -65,24 +62,35 @@ pub fn main() !void {
 
     var it = dir.iterate();
     while (try it.next()) |entry| {
-        if (entry.kind != .file or !std.mem.startsWith(u8, entry.name, "extinst.")) {
+        if (entry.kind != .file) {
             continue;
         }
 
-        std.debug.assert(std.mem.endsWith(u8, entry.name, ".grammar.json"));
-        const name = entry.name["extinst.".len .. entry.name.len - ".grammar.json".len];
-        const spec = try readRegistry(ExtensionRegistry, a, dir, entry.name);
-
-        std.sort.block(Instruction, spec.instructions, CmpInst{}, CmpInst.lt);
-
-        try exts.append(.{ .name = try a.dupe(u8, name), .spec = spec });
+        try readExtRegistry(&exts, a, dir, entry.name);
     }
 
+    try readExtRegistry(&exts, a, std.fs.cwd(), args[2]);
+
     var bw = std.io.bufferedWriter(std.io.getStdOut().writer());
     try render(bw.writer(), a, core_spec, exts.items);
     try bw.flush();
 }
 
+fn readExtRegistry(exts: *std.ArrayList(Extension), a: Allocator, dir: std.fs.Dir, sub_path: []const u8) !void {
+    const filename = std.fs.path.basename(sub_path);
+    if (!std.mem.startsWith(u8, filename, "extinst.")) {
+        return;
+    }
+
+    std.debug.assert(std.mem.endsWith(u8, filename, ".grammar.json"));
+    const name = filename["extinst.".len .. filename.len - ".grammar.json".len];
+    const spec = try readRegistry(ExtensionRegistry, a, dir, sub_path);
+
+    std.sort.block(Instruction, spec.instructions, CmpInst{}, CmpInst.lt);
+
+    try exts.append(.{ .name = try a.dupe(u8, name), .spec = spec });
+}
+
 fn readRegistry(comptime RegistryType: type, a: Allocator, dir: std.fs.Dir, path: []const u8) !RegistryType {
     const spec = try dir.readFileAlloc(a, path, std.math.maxInt(usize));
     // Required for json parsing.
@@ -374,14 +382,19 @@ fn renderInstructionClass(writer: anytype, class: []const u8) !void {
 }
 
 fn renderOperandKind(writer: anytype, operands: []const OperandKind) !void {
-    try writer.writeAll("pub const OperandKind = enum {\n");
+    try writer.writeAll(
+        \\pub const OperandKind = enum {
+        \\    Opcode,
+        \\
+    );
     for (operands) |operand| {
         try writer.print("{},\n", .{std.zig.fmtId(operand.kind)});
     }
     try writer.writeAll(
         \\
         \\pub fn category(self: OperandKind) OperandCategory {
-        \\return switch (self) {
+        \\    return switch (self) {
+        \\        .Opcode => .literal,
         \\
     );
     for (operands) |operand| {
@@ -395,10 +408,11 @@ fn renderOperandKind(writer: anytype, operands: []const OperandKind) !void {
         try writer.print(".{} => .{s},\n", .{ std.zig.fmtId(operand.kind), cat });
     }
     try writer.writeAll(
-        \\};
+        \\    };
         \\}
         \\pub fn enumerants(self: OperandKind) []const Enumerant {
-        \\return switch (self) {
+        \\    return switch (self) {
+        \\        .Opcode => unreachable,
         \\
     );
     for (operands) |operand| {
@@ -483,7 +497,9 @@ fn renderOpcodes(
         try writer.print("{} = {},\n", .{ std.zig.fmtId(inst.opname), inst.opcode });
     }
 
-    try writer.writeByte('\n');
+    try writer.writeAll(
+        \\
+    );
 
     for (aliases.items) |alias| {
         try writer.print("pub const {} = Opcode.{};\n", .{
@@ -495,7 +511,7 @@ fn renderOpcodes(
     try writer.writeAll(
         \\
         \\pub fn Operands(comptime self: Opcode) type {
-        \\return switch (self) {
+        \\    return switch (self) {
         \\
     );
 
@@ -505,10 +521,10 @@ fn renderOpcodes(
     }
 
     try writer.writeAll(
-        \\};
+        \\    };
         \\}
         \\pub fn class(self: Opcode) Class {
-        \\return switch (self) {
+        \\    return switch (self) {
         \\
     );
 
@@ -519,7 +535,12 @@ fn renderOpcodes(
         try writer.writeAll(",\n");
     }
 
-    try writer.writeAll("};\n}\n};\n");
+    try writer.writeAll(
+        \\   };
+        \\}
+        \\};
+        \\
+    );
 }
 
 fn renderOperandKinds(
@@ -844,7 +865,7 @@ fn parseHexInt(text: []const u8) !u31 {
 
 fn usageAndExit(arg0: []const u8, code: u8) noreturn {
     std.io.getStdErr().writer().print(
-        \\Usage: {s} <SPIRV-Headers repository path>
+        \\Usage: {s} <SPIRV-Headers repository path> <path/to/zig/src/codegen/spirv/extinst.zig.grammar.json>
         \\
         \\Generates Zig bindings for SPIR-V specifications found in the SPIRV-Headers
         \\repository. The result, printed to stdout, should be used to update