fixing descriptor sets population

build.zig

@@ -64,7 +64,7 @@ pub fn build(b: *std.Build) void {
     // Zig sandbox setup
 
     const sandbox_exe = b.addExecutable(.{
-        .name = "spirv_interpreter_sandbpx",
+        .name = "spirv_interpreter_sandbox",
         .root_module = b.createModule(.{
             .root_source_file = b.path("sandbox/main.zig"),
             .target = target,

sandbox/main.zig

@@ -26,18 +26,16 @@ pub fn main() !void {
 
         var ssbo: SSBO = .{};
 
-        try rt.writeDescriptorSet(allocator, std.mem.asBytes(&ssbo), 0, 0);
-
         for (0..16) |i| {
             for (0..16) |x| {
-                for (0..16) |y| {
                 const global_invocation_indices = [3]i32{
                     @as(i32, @intCast(i * 16 + x)),
-                        @as(i32, @intCast(y)),
+                    1,
                     1,
                 };
 
                 try rt.writeBuiltIn(std.mem.asBytes(&global_invocation_indices), .GlobalInvocationId);
+                try rt.writeDescriptorSet(allocator, std.mem.asBytes(&ssbo), 0, 0);
                 rt.callEntryPoint(allocator, entry) catch |err| switch (err) {
                     spv.Runtime.RuntimeError.OutOfBounds => continue,
                     else => return err,
@@ -45,7 +43,6 @@ pub fn main() !void {
                 try rt.readDescriptorSet(std.mem.asBytes(&ssbo), 0, 0);
             }
         }
-        }
 
         std.log.info("Output: {any}", .{ssbo});
 

sandbox/shader.nzsl

@@ -18,8 +18,8 @@ external
 }
 
 [entry(compute)]
-[workgroup(16, 16, 1)]
+[workgroup(16, 1, 1)]
 fn main(input: Input)
 {
-	ssbo.data[input.indices.x * input.indices.y] = i32(input.indices.x * input.indices.y);
+	ssbo.data[input.indices.x] = i32(input.indices.x);
 }

sandbox/shader.spv.txt

@@ -1,11 +1,11 @@
 Version 1.0
 Generator: 2560130
-Bound: 41
+Bound: 32
 Schema: 0
       OpCapability Capability(Shader)
       OpMemoryModel AddressingModel(Logical) MemoryModel(GLSL450)
-      OpEntryPoint ExecutionModel(GLCompute) %18 "main" %11
-      OpExecutionMode %18 ExecutionMode(LocalSize) 16 16 1
+      OpEntryPoint ExecutionModel(GLCompute) %17 "main" %11
+      OpExecutionMode %17 ExecutionMode(LocalSize) 16 1 1
       OpSource SourceLanguage(NZSL) 4198400
       OpSourceExtension "Version: 1.1"
       OpName %3 "SSBO"
@@ -14,7 +14,7 @@ Schema: 0
       OpMemberName %14 0 "indices"
       OpName %5 "ssbo"
       OpName %11 "global_invocation_indices"
-      OpName %18 "main"
+      OpName %17 "main"
       OpDecorate %5 Decoration(Binding) 0
       OpDecorate %5 Decoration(DescriptorSet) 0
       OpDecorate %11 Decoration(BuiltIn) BuiltIn(GlobalInvocationId)
@@ -36,33 +36,24 @@ Schema: 0
 %14 = OpTypeStruct %9
 %15 = OpTypePointer StorageClass(Function) %14
 %16 = OpTypeRuntimeArray %1
-%17 = OpConstant %1 i32(1)
-%31 = OpTypePointer StorageClass(Uniform) %2
-%40 = OpTypePointer StorageClass(Uniform) %1
+%26 = OpTypePointer StorageClass(Uniform) %2
+%31 = OpTypePointer StorageClass(Uniform) %1
  %5 = OpVariable %4 StorageClass(Uniform)
 %11 = OpVariable %10 StorageClass(Input)
-%18 = OpFunction %6 FunctionControl(0) %7
-%19 = OpLabel
-%20 = OpVariable %15 StorageClass(Function)
-%21 = OpAccessChain %13 %20 %12
-      OpCopyMemory %21 %11
-%22 = OpAccessChain %13 %20 %12
-%23 = OpLoad %9 %22
-%24 = OpCompositeExtract %8 %23 0
-%25 = OpAccessChain %13 %20 %12
-%26 = OpLoad %9 %25
-%27 = OpCompositeExtract %8 %26 1
-%28 = OpIMul %8 %24 %27
-%29 = OpBitcast %1 %28
-%30 = OpAccessChain %31 %5 %12
-%32 = OpAccessChain %13 %20 %12
-%33 = OpLoad %9 %32
-%34 = OpCompositeExtract %8 %33 0
-%35 = OpAccessChain %13 %20 %12
-%36 = OpLoad %9 %35
-%37 = OpCompositeExtract %8 %36 1
-%38 = OpIMul %8 %34 %37
-%39 = OpAccessChain %40 %30 %38
-      OpStore %39 %29
+%17 = OpFunction %6 FunctionControl(0) %7
+%18 = OpLabel
+%19 = OpVariable %15 StorageClass(Function)
+%20 = OpAccessChain %13 %19 %12
+      OpCopyMemory %20 %11
+%21 = OpAccessChain %13 %19 %12
+%22 = OpLoad %9 %21
+%23 = OpCompositeExtract %8 %22 0
+%24 = OpBitcast %1 %23
+%25 = OpAccessChain %26 %5 %12
+%27 = OpAccessChain %13 %19 %12
+%28 = OpLoad %9 %27
+%29 = OpCompositeExtract %8 %28 0
+%30 = OpAccessChain %31 %25 %29
+      OpStore %30 %24
       OpReturn
       OpFunctionEnd

src/Module.zig

@@ -212,7 +212,8 @@ fn populateMaps(self: *Self) ModuleError!void {
         if (result.variant == null or std.meta.activeTag(result.variant.?) != .Variable)
             continue;
 
-        var current_set: usize = 0;
+        var set: ?usize = null;
+        var binding: ?usize = null;
 
         for (result.decorations.items) |decoration| {
             switch (result.variant.?.Variable.storage_class) {
@@ -235,14 +236,17 @@ fn populateMaps(self: *Self) ModuleError!void {
                 .UniformConstant,
                 => {
                     switch (decoration.rtype) {
-                        .Binding => self.bindings[current_set][decoration.literal_1] = @intCast(id),
-                        .DescriptorSet => current_set = decoration.literal_1,
+                        .Binding => binding = decoration.literal_1,
+                        .DescriptorSet => set = decoration.literal_1,
                         else => {},
                     }
                 },
                 else => {},
             }
         }
+        if (set != null and binding != null) {
+            self.bindings[set.?][binding.?] = @intCast(id);
+        }
     }
 }