<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/152049>152049</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [SPIR-V] OpSpecConstantOp Bitcast error for `reversebits` vec2/vec3 cases for non-32-bit integers
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          kmpeng
      </td>
    </tr>
</table>

<pre>
    Discovered while running the offload-test-suite. This constant folding case:
``` hlsl
// RUN: %clang-dxc -spirv -fspv-target-env=vulkan1.3 -T cs_6_5 -enable-16bit-types %s

StructuredBuffer<uint16_t4> In : register(t0);
RWStructuredBuffer<uint16_t4> Out : register(u1);

[numthreads(1,1,1)]
void main() {
    Out[0].xy = reversebits(uint16_t2(0, 256));
}
```
generates a OpSpecConstantOp Bitcast operation, which is not supported by Vulkan:
``` 
# | Validation Error: [ VUID-VkShaderModuleCreateInfo-pCode-08737 ] | MessageID = 0xa5625282
# | vkCreateShaderModule(): pCreateInfo->pCode (spirv-val produced an error):
# | Specialization constant operation Bitcast requires Kernel capability
# | %38 = OpSpecConstantOp %ushort Bitcast %33
```
The same error occurs for vec3 constant folding `Out[0].xyz = reversebits(uint16_t3(0, 1, 256))`. 
These errors also occur when using `uint64_t`.

<br>

Crash stack:
```
# | Stack dump:
# | 0.  Program arguments: e:\\actions-runner\\_work\\offload-test-suite\\offload-test-suite\\llvm-project\\build\\bin\\offloader.exe E:\\actions-runner\\_work\\offload-test-suite\\offload-test-suite\\llvm-project\\build\\tools\\OffloadTest\\test\\clang-vk\\Feature\\HLSLLib\\Output\\reversebits.16.test.tmp/pipeline.yaml E:\\actions-runner\\_work\\offload-test-suite\\offload-test-suite\\llvm-project\\build\\tools\\OffloadTest\\test\\clang-vk\\Feature\\HLSLLib\\Output\\reversebits.16.test.tmp.o
# | Exception Code: 0xC0000005
# |  #0 0x00007ffdbb86a37a (C:\WINDOWS\System32\DriverStore\FileRepository\iigd_dch.inf_amd64_f42d50ef4c9376ba\igvk64.dll+0x57a37a)
# |  #1 0x00007ffdbb85b25a (C:\WINDOWS\System32\DriverStore\FileRepository\iigd_dch.inf_amd64_f42d50ef4c9376ba\igvk64.dll+0x56b25a)
# |  #2 0x00007ffdb9fe859a std::vector<std::vector<vvl::base::Device *,std::allocator<vvl::base::Device *> >,std::allocator<std::vector<vvl::base::Device *,std::allocator<vvl::base::Device *> > > >::operator[] D:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.29.30133\include\vector:1556:0
# |  #3 0x00007ffdb9fe859a vulkan_layer_chassis::CmdDispatch(struct VkCommandBuffer_T *, unsigned int, unsigned int, unsigned int) C:\SDKBuild\build-X64-1.4.313.1\Vulkan-ValidationLayers\layers\vulkan\generated\chassis.cpp:4480:0
# |  #4 0x00007ffdc976073d (C:\WINDOWS\SYSTEM32\vulkan-1.dll+0x6073d)
# | #5 0x00007ff7873bb71a `anonymous namespace'::VKDevice::createComputeCommands E:\actions-runner\_work\offload-test-suite\offload-test-suite\OffloadTest\lib\API\VK\Device.cpp:1083:0
# |  #6 0x00007ff787396377 llvm::Error::getPtr E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:277:0
# |  #7 0x00007ff787396377 llvm::Error::operator bool E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:241:0
# |  #8 0x00007ff787396377 `anonymous namespace'::VKDevice::executeProgram E:\actions-runner\_work\offload-test-suite\offload-test-suite\OffloadTest\lib\API\VK\Device.cpp:1188:0
# |  #9 0x00007ff7872b2b51 llvm::Error::getPtr E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:277:0
# | #10 0x00007ff7872b2b51 llvm::Error::operator= E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:218:0
# | #11 0x00007ff7872b2b51 llvm::Error::Error E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:198:0
# | #12 0x00007ff7872b2b51 llvm::ExitOnError::operator() E:\actions-runner\_work\offload-test-suite\offload-test-suite\llvm-project\llvm\include\llvm\Support\Error.h:1460:0
# | #13 0x00007ff7872b2b51 run E:\actions-runner\_work\offload-test-suite\offload-test-suite\OffloadTest\tools\offloader\offloader.cpp:136:0
# | #14 0x00007ff7872b22b8 main E:\actions-runner\_work\offload-test-suite\offload-test-suite\OffloadTest\tools\offloader\offloader.cpp:75:0
# | #15 0x00007ff787b6b060 invoke_main D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78:0
# | #16 0x00007ff787b6b060 __scrt_common_main_seh D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288:0
# | #17 0x00007ffdffd9e8d7 (C:\WINDOWS\System32\KERNEL32.DLL+0x2e8d7)
# | #18 0x00007ffe0155c34c (C:\WINDOWS\SYSTEM32\ntdll.dll+0x3c34c)
# `-----------------------------
# error: command failed with exit status: 0xc0000005
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzkWNFyozrSfhrlRgUFEgJ84QsHJ_WnJnMyNc7J_HvlEqIx2gBiJUGc8_RbAuyxE5-Z2ao9O7O1qbgMsrr7-7pbrZa4MXLXAiwRu0ZsfcV7Wym9fG46aHdXuSpel2tphBpAQ4FfKlkD1n3bynaHbQVYlWWteOFZMNYzvbTg48dKGixUayxvLS5VXbjZghtAdIWCFYqD6R9XtandALlF5BZ__v03RFcYESZq3u68Yi-wZzqpB-yVphs8y_UOrAftgOh66Otn3oY-xd4jFmYbbxn2oOV5DV4Y59J69rUD49QZZyNYbazuhe01FNd9WYJGNOtla8N4ayNEb_Bdi519DTtpLGhEUhsgskD0GgWrz1--J_7Q27fyfXiUd__suu0bW2nghUEkDRHJ5s8CsTUKVoOSBW64bBFJEVlglDhRjLFTjth1gNja379iRNdYwwDaQC6t03VAQhBJA0QyTFjs1B7NJ-tTz6NgtYMWNLdgMMcP3aYDkc0he-jwtbSCG4tV5-ZI1TqVL5UUFZYGt8pi03ed0hYKnL_ipzEWb6M7RpZilGT4ideyGBXhG62VHuPMrvHT73dr7-l5U_EC9EdV9DVkGriFu7ZUXpepArwgTWiCEVuPmj6CMXwHd-vRCcGes5gwkpITY8PzpONU6-RQZ7Y7MYDozWgDI5KOieYNvMadVkUvoMC8xTCiHSVPLDhvSV7LPyZKx1w_uuvoQA3_6KUGgz-AbqHGgnc8l7W0ryfqEGE0Hfm8CwQirDeV0vao0U2mb2L5WAE2vIEJLlZC9NrgUmk8gKDv1yKKg7OE-uMbGUUPGRWep1Uc-HgybWa7BvPaqMk6fqmgxb2ZrTllcbS1TmpeDDTLNaI301umuamwsVw8v8miU6-7n3HRN915NJzKxSetdpo3mOtd30BrjYv1WHBYhljGhQuL8VztAj2NbV-Ufp4e35exb4_X9dB4nVZ_B2GnkbyXdTE_yvZMGrQPe8A3PwWMVao20-PDJP8IZp5mj09TwR1mALfAXZ2bXv7vfnN_L_NZRW-7fpY5SRc_jH2nzLdNh8htJzuoZQv-K2_q_xXevjpJyZu9gG4sBK68uFQM9lkw_rGTaRgRGuBg78aTsizyPI05TbirR9nkti93v60fvmwQyzavxkJDCWLZWssB9MaqEeytrOEzdMpIq_QrYpmUu2JbiMqXbbnlTRFH2zIiBQugjMSCJnHO3azd8BxHflHXiFwHe5Y4y25ln-MLz_GxnLCfgy92lt_jI6f4FiWkbMGxsYWDR1cDCOu2m-z9yDDU00g-dyZ0tYZBCrcbrBD5KsHrWgn-I0L0BruS9iey_0EIh8_087QtKT31eHg9Re5QMV14XJuU7tOxtrPsoxRaGVVa_CRNz2u8sX0hFWIZCUI3IVNN07duE2PZk1sTj_Nq-7gZX8PIJwufBiGlLpCtqPvCZcKB-CpkLEZ0FbyJJb0Uy6nR29b8FfRWVK5jNROvrCnW0nTcispt4GN_hp-eHTrezl3a9nH2Je7bsdUtsGzt998XeE7wzfrD9VxWxvLi_X8ceaEf-TSkfugcMOLzvrY49w6p80Z9eJgoIJYdmi6nbabii87tZ1GUBhc8Ep14RCySOEhocXn1_W3zePNxXH2TNS88Lp1R6nzlIELZV9VJmtA8T0Lu9mreqva1Ub3BLW_AdFwAIsnk8acPU6pNb2LspDLVdP345bxuDvX-XbE_VPqL5fzi4HnhrsdivPp053z-wVWZEcrsvzBI6QX_xeckFzFNEuw2jonBoRlFdLUD-8nqfyP6N9vTaPR0McwDm6mRRiwbwfgVoiuSJBe4JD_M5bDgca5U_YtQisILlNJLlP6lHIQ9iN7CoZj9pOQL0_QCu8UZO5KTnIX_jcnnuoDgh7kcdxu6_kUIhW-D4wiFP0xofPw1qISLS1TId6jspX1oL0VoumX4NZhF8dv9z1Gjl6jpvv3LFvrh3HA8u52d4-blTt82Lw5q9BYqydPxMuenYk3YBajnW38e50EcYNkO6hm2I-K5ReQnIF2r44wZLVyPIQ7GxRjIQRjLte2744yv77CHrVBNo1pftq53TS4lcXwJ03ZrhLaz9Ahta6D6i-GRd8Xc4TvZfYuyLBaQFsn3zkEfbj7_dnNPib--vx87MeKk3nVi4ck2CEHImKCR-F6X19qiro8tHnUiJ4rjwPvW3zwNDndxYmrecMllDQV-kbbCsJcWG8ttb6YDrDg5wB6uZ66KJS0WdMGvYBkmLKJRvIjDq2qZE8JIwfKcxTSIAhqVLI-ioCiTKElYGF_JJQkIC9IgIoTGQeinKSFpWAYphZIG5QJFATRc1r6rGr7SuytpTA_LkJEgWlzVPIfajPfWhLTwgsdfESGIra_0cixFeb8zKApqaaz5qsZKW48X3ptPd5-9J3ck-tML0OlCrVTaufT0giwO8ACCIHI7XbFxA9ONW6tajxIvl9YdJGAH2lz1ul5W1nbjuWW87N5JW_W5L1SDyO1YFqevY_UktyMfg8jtTHhYkn8GAAD__4AXSts">