[clang] [HLSL][SPIRV] Allow large z value in numthreads (PR #144934)

[Nathan Gauër via cfe-commits]

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@@ -1033,12 +1033,15 @@ void SemaHLSL::handleRootSignatureAttr(Decl *D, const ParsedAttr &AL) {
 void SemaHLSL::handleNumThreadsAttr(Decl *D, const ParsedAttr &AL) {
   llvm::VersionTuple SMVersion =
       getASTContext().getTargetInfo().getTriple().getOSVersion();
+  bool IsDXIL = getASTContext().getTargetInfo().getTriple().getArch() ==
+                llvm::Triple::dxil;
+
   uint32_t ZMax = 1024;
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Keenuts wrote:

The highest value I could found was on AMD's 9070 -> 1024x1024x1024
High-end NV are 1024x1024x64
So seems that in practice, this limit is OK. But in theory a hardware could set this limit to any value.

https://github.com/llvm/llvm-project/pull/144934