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

[Justin Bogner via llvm-commits]

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@@ -72,9 +72,24 @@ ROOT_ELEMENT_FLAG(11, SamplerHeapDirectlyIndexed)
 #undef ROOT_ELEMENT_FLAG
 #endif // ROOT_ELEMENT_FLAG
 
+ 
+// ROOT_DESCRIPTOR_FLAG(bit offset for the flag, name).
+#ifdef ROOT_DESCRIPTOR_FLAG
+
+ROOT_DESCRIPTOR_FLAG(0, NONE)
+ROOT_DESCRIPTOR_FLAG(1, DATA_VOLATILE)
+ROOT_DESCRIPTOR_FLAG(2, DATA_STATIC_WHILE_SET_AT_EXECUTE)
+ROOT_DESCRIPTOR_FLAG(3, DATA_STATIC)
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bogner wrote:

Hm, these values are wrong. We shouldn't have `NONE` here - when we shift to make the values, we want DATA_VOLATILE to be 1, DATA_STATIC_WHILE_SET_AT_EXECUTE to be 2, and DATA_STATIC to be 4, but as is they're 2, 4, and 8 respectively.

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