[clang] [llvm] [HLSL] Update Frontend to support version 1.2 of root signature (PR #160616)

[Justin Bogner via llvm-commits]

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@@ -38,7 +40,7 @@ bool verifyRootDescriptorFlag(uint32_t Version, uint32_t FlagsVal) {
   if (Version == 1)
     return Flags == FlagT::DataVolatile;
 
-  assert(Version == 2 && "Provided invalid root signature version");
+  assert((Version == 2 || Version == 3) && "Provided invalid root signature version");
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bogner wrote:

`Version <= 3` might be clearer

https://github.com/llvm/llvm-project/pull/160616