[llvm] [HLSL] Leave out entryname from string table for PSV versions < 3 (PR #191528)

[Tex Riddell via llvm-commits]

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@@ -770,8 +770,11 @@ void DXContainerYAML::PSVInfo::mapInfoForVersion(yaml::IO &IO) {
   IO.mapRequired("NumThreadsY", Info.NumThreadsY);
   IO.mapRequired("NumThreadsZ", Info.NumThreadsZ);
 
-  if (Version == 2)
+  if (Version == 2) {
+    if (!IO.outputting())
+      IO.mapOptional("EntryName", EntryName);
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tex3d wrote:

Why is `EntryName` added as optional for v2 when it requires v3? Why not just return here?

https://github.com/llvm/llvm-project/pull/191528