[llvm] [DirectX] Adding support for Root Descriptors in obj2yaml/yaml2obj (PR #137259)

[via llvm-commits]

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@@ -580,7 +585,28 @@ struct ProgramSignatureElement {
 
 static_assert(sizeof(ProgramSignatureElement) == 32,
               "ProgramSignatureElement is misaligned");
+namespace RST0 {
+namespace v0 {
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joaosaffran wrote:

I will address this in a follow-up PR. Existing test would also require updates, and I don't want to overpopulate this PR with such changes. Are you okay with this approach @damyanp @spall ?

https://github.com/llvm/llvm-project/pull/137259