OpDecorate with Block/BufferBlock isn't working properly

[ccleavinger]

Context

I'm working on a basic compiler for converting Rust functions to SPIR-V using proc macros and rspirv (to achieve similar functionality as CUDA)

Error

When compiling buffers to parameters I'm having an issue where the correlating OpTypeStruct (this: %_struct_5 = OpTypeStruct %_runtimearr_float) doesn't actually get decorated with Block despite marking aforementioned type with Block using rspirv.

Code Snippet

This is from withing a struct that uses a handful of hashmaps to store and access variable ids and type ids:

                    // get word of the type of the elements in the runtime arr
                    let base_word = self.types.get(arr_ty).ok_or(anyhow!(
                        "failed to retrieve base type of runtime arr: {:?}",
                        arr_ty
                    ))?;

                    // create runtime arr type (pretty simple)
                    let runtime_ty = self.spirv_builder.type_runtime_array(*base_word);

                    // create a struct type
                    let struct_ty = self.spirv_builder.type_struct(vec![runtime_ty]);

                    self.spirv_builder.decorate(
                        struct_ty,
                        rspirv::spirv::Decoration::Block,
                        vec![], 
                    );

                    let lit_0 = self.literals
                        .get(&MimirLit::Int32(0))
                        .ok_or(anyhow!("Failed to find literal 0 for struct decoration"))?;
                    self.spirv_builder.member_decorate(
                        struct_ty, 
                        *lit_0,
                        rspirv::spirv::Decoration::Offset,
                        vec![rspirv::dr::Operand::LiteralBit32(0)]
                    );

SPIR-V

Outputted SPIR-V for my compiler:
saxpy.spirv.txt
Because the SPIR-V contains %_runtimearr_float = OpTypeRuntimeArray %float and
%_struct_5 = OpTypeStruct %_runtimearr_float the code for generating buffers is being called but the types are not being decorated properly.

Thank you in advance for any help, thank you!

[msiglreith]

Hi,

which version you are using? Unfortunately I'm unable to open the file, reports an error when trying to download. I put together a small program with rspirv:0.12.0 which outputs the decoration just fine:

use rspirv::binary::{Assemble, Disassemble};
use rspirv::spirv;

fn main() {
    let mut b = rspirv::dr::Builder::new();
    b.set_version(1, 0);
    b.capability(spirv::Capability::Shader);
    b.memory_model(spirv::AddressingModel::Logical, spirv::MemoryModel::GLSL450);

    let ty_f32 = b.type_float(32);
    let runtime_ty = b.type_runtime_array(ty_f32);
    let struct_ty = b.type_struct(vec![runtime_ty]);

    b.decorate(struct_ty, rspirv::spirv::Decoration::Block, vec![]);

    b.member_decorate(
        struct_ty,
        0, // note: this should be an immediate value not an id
        rspirv::spirv::Decoration::Offset,
        vec![rspirv::dr::Operand::LiteralBit32(0)],
    );

    let module = b.module();
    let code = module.assemble();

    let mut loader = rspirv::dr::Loader::new();
    rspirv::binary::parse_words(&code, &mut loader).unwrap();
    let module = loader.module();

    println!("{}", module.disassemble());
}

; SPIR-V
; Version: 1.0
; Generator: rspirv
; Bound: 4
OpCapability Shader
OpMemoryModel Logical GLSL450
OpDecorate %3 Block
OpMemberDecorate %3 0 Offset 0
%1 = OpTypeFloat 32
%2 = OpTypeRuntimeArray %1
%3 = OpTypeStruct %2

[ccleavinger]

I'm using rspirv: 0.12.0 as well, the outputted SPIR-V is as below, I'm unsure what could be causing this. I might have to line by line debug my compiler once I'm out of school.

Outputted SPIR_V:

; SPIR-V
; Version: 1.2
; Generator: Google rspirv; 0
; Bound: 64
; Schema: 0
               OpCapability Shader
          %1 = OpExtInstImport "GLSL.std.450"
               OpMemoryModel Logical GLSL450
               OpEntryPoint GLCompute %35 "main" %gl_WorkGroupID %gl_LocalInvocationID
               OpSource Unknown 1
               OpName %x "x"
               OpName %y "y"
               OpName %idx "idx"
               OpName %idx "idx"
               OpDecorate %20 SpecId 0
               OpDecorate %21 SpecId 1
               OpDecorate %22 SpecId 2
               OpDecorate %gl_WorkGroupID BuiltIn WorkgroupId
               OpDecorate %gl_WorkGroupSize BuiltIn WorkgroupSize
               OpDecorate %gl_LocalInvocationID BuiltIn LocalInvocationId
               OpDecorate %x Binding 0
               OpDecorate %x DescriptorSet 0
               OpDecorate %y Binding 1
               OpDecorate %y DescriptorSet 0
       %void = OpTypeVoid
       %uint = OpTypeInt 32 0
     %v3uint = OpTypeVector %uint 3
      %float = OpTypeFloat 32
        %int = OpTypeInt 32 1
%_runtimearr_float = OpTypeRuntimeArray %float
  %_struct_8 = OpTypeStruct %_runtimearr_float
%_ptr_Function_float = OpTypePointer Function %float
%_ptr_Function_int = OpTypePointer Function %int
%_ptr_PushConstant_int = OpTypePointer PushConstant %int
%_ptr_PushConstant_float = OpTypePointer PushConstant %float
%_ptr_Input_v3uint = OpTypePointer Input %v3uint
%_ptr_Function_uint = OpTypePointer Function %uint
%_ptr_Uniform_float = OpTypePointer Uniform %float
%_ptr_Uniform__struct_8 = OpTypePointer Uniform %_struct_8
       %bool = OpTypeBool
%_ptr_Function_bool = OpTypePointer Function %bool
         %19 = OpTypeFunction %void
         %20 = OpSpecConstant %uint 1
         %21 = OpSpecConstant %uint 1
         %22 = OpSpecConstant %uint 1
%_ptr_Input_uint = OpTypePointer Input %uint
%gl_WorkGroupID = OpVariable %_ptr_Input_v3uint Input
%gl_WorkGroupSize = OpSpecConstantComposite %v3uint %20 %21 %22
%gl_LocalInvocationID = OpVariable %_ptr_Input_v3uint Input
      %int_2 = OpConstant %int 2
      %int_1 = OpConstant %int 1
      %int_0 = OpConstant %int 0
          %x = OpVariable %_ptr_Uniform__struct_8 Uniform
          %y = OpVariable %_ptr_Uniform__struct_8 Uniform
 %_struct_32 = OpTypeStruct %int %float
%_ptr_PushConstant__struct_32 = OpTypePointer PushConstant %_struct_32
         %34 = OpVariable %_ptr_PushConstant__struct_32 PushConstant
    %int_1_0 = OpConstant %int 1
         %35 = OpFunction %void None %19
         %36 = OpLabel
        %idx = OpVariable %_ptr_Function_uint Function
         %39 = OpAccessChain %_ptr_Input_uint %gl_WorkGroupID %int_0
         %40 = OpLoad %uint %39
         %41 = OpCompositeExtract %uint %gl_WorkGroupSize 0
         %42 = OpIMul %uint %40 %41
         %43 = OpAccessChain %_ptr_Input_uint %gl_LocalInvocationID %int_0
         %44 = OpLoad %uint %43
         %45 = OpIAdd %uint %42 %44
               OpStore %idx %45
         %46 = OpLoad %uint %idx
         %47 = OpAccessChain %_ptr_PushConstant_int %34 %int_0
         %48 = OpLoad %int %47
         %49 = OpULessThan %bool %46 %48
               OpSelectionMerge %50 None
               OpBranchConditional %49 %51 %50
         %51 = OpLabel
         %52 = OpLoad %uint %idx
         %53 = OpAccessChain %_ptr_Uniform_float %y %int_0 %52
         %54 = OpAccessChain %_ptr_PushConstant_float %34 %int_1_0
         %55 = OpLoad %float %54
         %56 = OpLoad %uint %idx
         %57 = OpAccessChain %_ptr_Uniform_float %x %int_0 %56
         %58 = OpLoad %float %57
         %59 = OpFMul %float %55 %58
         %60 = OpLoad %uint %idx
         %61 = OpAccessChain %_ptr_Uniform_float %y %int_0 %60
         %62 = OpLoad %float %61
         %63 = OpFAdd %float %59 %62
               OpStore %53 %63
               OpBranch %50
         %50 = OpLabel
               OpReturn
               OpFunctionEnd