[clang] [llvm] [HLSL] Adding HLSL `clip` function. (PR #114588)

[Farzon Lotfi via cfe-commits]

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@@ -633,7 +633,8 @@ void RequirementHandler::initAvailableCapabilities(const SPIRVSubtarget &ST) {
   if (ST.isAtLeastSPIRVVer(VersionTuple(1, 6)))
     addAvailableCaps({Capability::DotProduct, Capability::DotProductInputAll,
                       Capability::DotProductInput4x8Bit,
-                      Capability::DotProductInput4x8BitPacked});
+                      Capability::DotProductInput4x8BitPacked,
+                      Capability::DemoteToHelperInvocation});
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farzonl wrote:

This looks like a spec bug [OpDemoteToHelperInvocationEXT was updated to 1.6](https://github.com/KhronosGroup/SPIRV-Headers/blob/996c728cf7dcfb29845cfa15222822318f047810/include/spirv/unified1/spirv.core.grammar.json#L6475 ):
with this pr: https://github.com/KhronosGroup/SPIRV-Headers/pull/259



https://github.com/llvm/llvm-project/pull/114588