[llvm] [DXIL] Add support for root signature flag element in DXContainer (PR #123147)

[Damyan Pepper via llvm-commits]

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@@ -550,18 +548,12 @@ static_assert(sizeof(ProgramSignatureElement) == 32,
 
 struct RootSignatureValidations {
 
-  static Expected<uint32_t> validateRootFlag(uint32_t Flags) {
-    if ((Flags & ~0x80000fff) != 0)
-      return llvm::make_error<BinaryStreamError>("Invalid Root Signature flag");
-    return Flags;
+  static bool validateRootFlag(uint32_t Flags) {
+    return (Flags & ~0x80000fff) != 0;
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damyanp wrote:

> return (Flags & ~0x80000fff) != 0;

Wondering why this is `0x80000fff` rather than `0xfff`?

https://github.com/llvm/llvm-project/pull/123147