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

[Joshua Batista 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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bob80905 wrote:

Without this, we wouldn't be able to construct the yaml test for PSV v2 (since there would be no concept of an EntryName field), so we wouldnt be able to construct a roundtrip test.
It's just for testing purposes, but we could return here.
But without this code we wouldn't be able to test that EntryName gets removed after converting back from obj to yaml.

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