[SPIR-V] generated SPIR-V is invalid: [VUID-StandaloneSpirv-OpTypeImage-06924] Cannot store to OpTypeImage, OpTypeSampler, OpTypeSampledImage, or OpTypeAccelerationStructureKHR objects

[gjaegy]

Description
Invalid SPIR-V is generated with the latest release and with head, when compiling with debug

Steps to Reproduce
Compile with the following command:
dxc.exe mipmap_gen_envmap.hlsl -E maincomp -T cs_6_0 -spirv -fspv-target-env=vulkan1.1 -Wall -Wno-unused-const-variable -D imBINDLESS=0 -fspv-extension=SPV_KHR_non_semantic_info -fspv-debug=vulkan-with-source -fspv-extension=SPV_EXT_descriptor_indexing

Actual Behavior
fatal error: generated SPIR-V is invalid: [VUID-StandaloneSpirv-OpTypeImage-06924] Cannot store to OpTypeImage, OpTypeSampler, OpTypeSampledImage, or OpTypeAccelerationStructureKHR objects
OpStore %927 %3239

Problem doesn't occur without the "-fspv-debug=vulkan-with-source" option

Environment

• DXC version February 2025
• Host Operating System Windows 11

Please contact me and I will send you a repro case per email.

[sd20134]

I get the same error on code

[s-perron]

Can you provide a shader that reproduces this issue? This type of error typically happens because the optimizer failed to copy propagate the temporaries that stored the opaque types like the images and samplers. Without a specific example, I cannot tell why it did not optimize. Considering that the debug info makes a difference, it could be that an extension is added that turns off optimization.

If you can't provide a specific example, please compile with -Vd and add a comment with the OpExtension instruction at the top of the SPIR-V.

[gjaegy]

Yes I can. How can I send it to you (I am not allowed to make the shader public) ?

[s-perron]

If you can't make the shader public, then I probably can't accept it privately unless you have NDA in place with Google. I cannot accept your secrets. Can you make the extensions public? That is most likely the problem.

EDIT changed to "can't accept it"

[gjaegy]

Yes I simply don't want to publish it here, but can send it to you per email?

[gjaegy]

I can also upload it on our server, and send you the link. Let me know when you are available to download...

[s-perron]

Could you try running:

dxc.exe mipmap_gen_envmap.hlsl -E maincomp -T cs_6_0 -spirv -fspv-target-env=vulkan1.1 -Wall -Wno-unused-const-variable -D imBINDLESS=0 -fspv-extension=SPV_KHR_non_semantic_info -fspv-debug=vulkan-with-source -fspv-extension=SPV_EXT_descriptor_indexing -Vd

I added -Vd, and then past the OpExtension instructions that are output? I'll try other ways to reproduce the problem.

[gjaegy]

please download the repro case here:

http://www.imagine3d.fr/_temp/dxc_bugs.rar

and let me know as soon as you've downloaded it !

[gjaegy]

I've removed the link, let me know once you are ready to download (or drop me an email [email protected])

[s-perron]

I won't download from the link. The IP issues are too vague for me to be able to do that. You'll have to find something you can make truly public, or try to narrow down the problem yourself. The first thing to try is my suggestion above.

[gjaegy]

I'm the founder and CEO of the company.

By not allowed, I meant I don't want the code to be available to everyone. There is nothing fancy in the code, but it's not an open source software either.

I'm happy for you to get your hands on it in order to fix the issue.

Just drop me an email and I'll send it to you

[s-perron]

I'll have to see what our legal team says about it.

[gjaegy]

Dear, why so much complexity...

[gjaegy]

output.txt

attached the output when compiling the shader with the additional -Vd parameter

[gjaegy]

That's the output without the -Vd parameter:

dxc.exe mipmap_gen_previousframecolor.hlsl -E maincomp -T cs_6_0 -spirv -fspv-target-env=vulkan1.1 -Wall -Wno-unused-const-variable -D imBINDLESS=0 -fspv-extension=SPV_KHR_non_semantic_info -fspv-debug=vulkan-with-source -fspv-extension=SPV_EXT_descriptor_indexing >> output_novd.txt
fatal error: generated SPIR-V is invalid: [VUID-StandaloneSpirv-OpTypeImage-06924] Cannot store to OpTypeImage, OpTypeSampler, OpTypeSampledImage, or OpTypeAccelerationStructureKHR objects
OpStore %927 %3239

note: please file a bug report on https://github.com/Microsoft/DirectXShaderCompiler/issues with source code if possible

[TheMostDiligent]

Hello,
I am getting the same issue starting with the Vulkan SDK 1.4.304.0. Before that SDK, the same shader was compiling successfully.
Here is the shader source code:

RayTracing.txt

It is a compute shader with inline ray tracing.
Here are the command line args: -spirv -fspv-reflect -Od -fspv-target-env=vulkan1.2 -Zpc
Here is the error log that I get:

fatal error: generated SPIR-V is invalid: [VUID-StandaloneSpirv-OpTypeImage-06924] Cannot store to OpTypeImage, OpTypeSampler, OpTypeSampledImage, or OpTypeAccelerationStructureKHR objects
  OpStore %140 %236

note: please file a bug report on https://github.com/Microsoft/DirectXShaderCompiler/issues with source code if possible

[s-perron]

I'll try to take a look next week. Possibly not the same issue as @gjaegy's. Hopefully it is.

[s-perron]

I have a fix for @TheMostDiligent's issue. The missing extension was inserted because of -fspv-reflect, so it will not likely fix @gjaegy's problem.

[s-perron]

The part of the code that I fixed had not changed, so does not show me why it regressed. I'll try to track down the change that caused the regression. That might point to something else.

[s-perron]

The "regression" was caused by KhronosGroup/SPIRV-Tools#5368. The code DXC was generating was always invalid. The difference is that the validator now recognizes that it is invalid.

As a workaround you can compile with -Vd. This turns off validation, and will generate the same code that was generated before. As long as the validation layers are turned off, you should see the same results as before when running a pipeline with the shader.

To fix the issue more or different optimizations are needed to properly legalize the code. Without seeing the code, I cannot determine what is needed.

@gjaegy Since this is an optimization problem, we could also try getting a reduced SPIR-V test case that will not give away any trade secrets. Here are the steps you can follow:

1. Dump the SPIR-V before optimizations are run by adding -Vd -fcgl to the dxc command line. Call it t.spv.
2. Write a small script that return 0 if and only if a spir-v binary has the same problem. On Linux this could be called b.sh:

spirv-opt $1 -o o.spv --legalize-hlsl -O --skip-validation && spirv-val --target-env vulkan1.2 o.spv 2>&1 | grep "VUID-StandaloneSpirv-OpTypeImage-06924"

3. Check that you can reproduce the problem on the command line using spirv-opt:

./b.sh t.spv; echo $?

4. use spirv-reduce to reduce the spir-v binary:

spirv-reduce --before-hlsl-legalization t.spv -o r.spv -- ./b.sh

Hopefully you can post the disassembly of r.spv publicly. spirv-reduce is part of SPIR-V Tools and is available in the Vulkan SDK.

[TheMostDiligent]

I have a fix for @TheMostDiligent's issue.
The "regression" was caused by KhronosGroup/SPIRV-Tools#5368. The code DXC was generating was always invalid.

So is the fix on DXC or SPIRV-Tools side? If the code DXC produces is valid, then the issue should be fixed on SPIRV-Tools side?
Or did you find a workaround on DXC side?

[s-perron]

@TheMostDiligent For your test case, the fix is an improvement to the optimizer: KhronosGroup/SPIRV-Tools#6075. After that, the validator will no longer complain.

[gjaegy]

Again, I'm happy to share the HLSL, there is nothing fancy about it. Simply drop me an email and I'll send it to you.

Otherwise I'll try to follow the steps you've mentioned above.

[gjaegy]

Actually I have no linux system available in the office. And running the "spirv-opt" command leads to an error (error: line 0: Invalid SPIR-V magic number '5053203b').

Attached the source shader files. Rename the file to 7181.rar and extract the files.

The command line used is the following one:

dxc.exe mipmap_gen_previousframecolor.hlsl -E maincomp -T cs_6_0 -spirv -fspv-target-env=vulkan1.1 -Wall -Wno-unused-const-variable -D imBINDLESS=0 -fspv-extension=SPV_KHR_non_semantic_info -fspv-debug=vulkan-with-source -fspv-extension=SPV_EXT_descriptor_indexing

[s-perron]

Thanks for that. Here is a small reproducer: https://godbolt.org/z/shcsf4E8r. If the -fspv-debug=vulkan-with-source option is removed, then the problem goes away.

The issue seems in the spirv-opt pass copy-propagate-arrays. That pass will try to replace the image operand in the OpImageTexelPointer instruction another if on is a copy of the other. In this case is fails because the operand in the OpImageTexelPointer is also used in a debug instruction. The pass does not know what to do with that.

I should be able to update the pass to not consider debug instructions as bad uses.

[gjaegy]

Great news !
Do you think that could be related to issue #7182 ?