[llvm] [HLSL] Add descriptor table metadata parsing (PR #142492)

[via llvm-commits]

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@@ -236,11 +323,84 @@ static bool verifyRegisterValue(uint32_t RegisterValue) {
 // This Range is reserverved, therefore invalid, according to the spec
 // https://github.com/llvm/wg-hlsl/blob/main/proposals/0002-root-signature-in-clang.md#all-the-values-should-be-legal
 static bool verifyRegisterSpace(uint32_t RegisterSpace) {
-  return !(RegisterSpace >= 0xFFFFFFF0 && RegisterSpace <= 0xFFFFFFFF);
+  return !(RegisterSpace >= 0xFFFFFFF0 && RegisterSpace < 0xFFFFFFFF);
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joaosaffran wrote:

This change happen because in Descriptor Ranges can contain a Register Space of -1. But, it might be better to just have a separate method to deal with Ranges validation, thoughts ?

https://github.com/llvm/llvm-project/pull/142492