Test Feature/HLSLLib/reversebits.16.test fails on Windows Vulkan QC Clang

[Icohedron]

The test Feature/HLSLLib/reversebits.16.test fails on Windows Vulkan QC Clang but passes or xpasses on all other runners.

Results from scheduled runs today (2025-11-28):

╭───┬──────────────────────┬─────────────┬─────────────────────────────┬────────┬─────────────────────────────────────╮
│ # │      timestamp       │   run-id    │          workflow           │ status │                test                 │
├───┼──────────────────────┼─────────────┼─────────────────────────────┼────────┼─────────────────────────────────────┤
│ 0 │ 2025-11-28T18:05:50Z │ 19771050617 │ Windows Vulkan AMD DXC      │ PASS   │ Feature/HLSLLib/reversebits.16.test │
│ 1 │ 2025-11-28T22:01:55Z │ 19774580028 │ Windows Vulkan Intel DXC    │ PASS   │ Feature/HLSLLib/reversebits.16.test │
│ 2 │ 2025-11-28T02:35:49Z │ 19752462306 │ Windows Vulkan NVIDIA DXC   │ PASS   │ Feature/HLSLLib/reversebits.16.test │
│ 3 │ 2025-11-28T18:02:29Z │ 19770990351 │ Windows Vulkan QC DXC       │ PASS   │ Feature/HLSLLib/reversebits.16.test │
│ 4 │ 2025-11-28T22:06:03Z │ 19774646176 │ Windows Vulkan QC Clang     │ XFAIL  │ Feature/HLSLLib/reversebits.16.test │
│ 5 │ 2025-11-28T18:06:34Z │ 19771064332 │ Windows Vulkan AMD Clang    │ XPASS  │ Feature/HLSLLib/reversebits.16.test │
│ 6 │ 2025-11-28T20:04:28Z │ 19772907221 │ Windows Vulkan Intel Clang  │ XPASS  │ Feature/HLSLLib/reversebits.16.test │
│ 7 │ 2025-11-28T06:02:32Z │ 19755520578 │ Windows Vulkan NVIDIA Clang │ XPASS  │ Feature/HLSLLib/reversebits.16.test │
╰───┴──────────────────────┴─────────────┴─────────────────────────────┴────────┴─────────────────────────────────────╯

Logs: https://github.com/llvm/offload-test-suite/actions/runs/19841117939/job/56849629935#step:12:2641

FAIL: OffloadTest-clang-vk :: Feature/HLSLLib/reversebits.16.test (166 of 294)
******************** TEST 'OffloadTest-clang-vk :: Feature/HLSLLib/reversebits.16.test' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 64
c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\split-file.exe C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\OffloadTest\test\Feature\HLSLLib\reversebits.16.test C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp
# executed command: 'c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\split-file.exe' 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\OffloadTest\test\Feature\HLSLLib\reversebits.16.test' 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp'
# RUN: at line 65
c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\clang-dxc.exe -spirv -fspv-target-env=vulkan1.3 -fspv-extension=DXC --dxv-path=C:/Users/github/dev/_work/offload-test-suite/offload-test-suite/DXC/build/bin -enable-16bit-types -T cs_6_5 -Fo C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp.o C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp/source.hlsl
# executed command: 'c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\clang-dxc.exe' -spirv -fspv-target-env=vulkan1.3 -fspv-extension=DXC --dxv-path=C:/Users/github/dev/_work/offload-test-suite/offload-test-suite/DXC/build/bin -enable-16bit-types -T cs_6_5 -Fo 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp.o' 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp/source.hlsl'
# RUN: at line 66
c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\offloader.exe -debug-layer C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp/pipeline.yaml C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp.o
# executed command: 'c:\users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\bin\offloader.exe' -debug-layer 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp/pipeline.yaml' 'C:\Users\github\dev\_work\offload-test-suite\offload-test-suite\llvm-project\build\tools\OffloadTest\test\clang-vk\Feature\HLSLLib\Output\reversebits.16.test.tmp.o'
# .---command stdout------------
# | Using Vulkan API
# | Physical device created.
# | Shader module created.
# | Copy command buffer created.
# | Memory buffers created.
# | Executed copy command buffer.
# | Execute command buffer created.
# | Descriptors: { type = 7, count = 2 }
# | Descriptor pool created.
# | Binding 2 descriptors.
# | Num Descriptor sets: 1
# | Updating Descriptor [0] { 0, 0 }
# | Updating Descriptor [1] { 0, 1 }
# | WriteDescriptors: 2
# | Descriptor sets created.
# | Compute pipeline created.
# | Dispatched compute shader: { 1, 1, 1 }
# | Commands created.
# | Executed compute command buffer.
# | Compute pipeline created.
# | Cleanup complete.
# `-----------------------------
# .---command stderr------------
# | Test failed: Test1
# | Comparison Rule: BufferExact
# | Expected:
# | ---
# | Name:            ExpectedOut
# | Format:          UInt16
# | Stride:          8
# | Data:            [ 0, 32768, 4096, 128, 65534, 65535, 43690, 3855, 4592, 
# |                    49155, 0, 128 ]
# | OutputProps:
# |   Height:          0
# |   Width:           0
# |   Depth:           0
# | ...
# | Got:
# | ---
# | Name:            Out
# | Format:          UInt16
# | Stride:          8
# | Data:            [ 0, 0, 0, 0, 0, 65535, 0, 65535, 0, 65535, 0, 128 ]
# | OutputProps:
# |   Height:          0
# |   Width:           0
# |   Depth:           0
# | ...
# | Full Hex 64bit representation of Expected Buffer Values:
# | [ 0x0, 0x8000, 0x1000, 0x80, 0xfffe, 0xffff, 0xaaaa, 0xf0f, 0x11f0, 0xc003, 0x0, 0x80 ]
# | Full Hex 64bit representation of Actual Buffer Values:
# | [ 0x0, 0x0, 0x0, 0x0, 0x0, 0xffff, 0x0, 0xffff, 0x0, 0xffff, 0x0, 0x80 ]
# | 
# `-----------------------------
# error: command failed with exit status: 1