[llvm] [DirectX] adding support in obj2yaml and yaml2obj to root constants (PR #127840)

[via llvm-commits]

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@@ -14,20 +14,18 @@ Parts:
     Size:            24
     RootSignature:
       Version: 2
-      NumParameters: 1
-      RootParametersOffset: 3
       NumStaticSamplers: 4
       StaticSamplersOffset: 5
+      Parameters: []
       AllowInputAssemblerInputLayout: true
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joaosaffran wrote:

Maybe, but I found it annoying to manually set those when writing the tests. I think I could make it optional, so while reading the yaml, this value is ignored, but when writing we can see the calculated offset and make sure it is correct. Would that be reasonable?

https://github.com/llvm/llvm-project/pull/127840