[clang] [llvm] [mlir] Enforce single-operand form for llvm.loop.vectorize.predicate metadata (PR #213902)

[Michael Kruse via llvm-commits]

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@@ -83,6 +85,17 @@ void LoopAnnotationConversion::convertBoolNode(StringRef name, BoolAttr attr,
                               llvm::ConstantAsMetadata::get(cstValue)}));
 }
 
+/// Emits the single-operand node of an enable/disable pair. As in
+/// convertBoolNode, \p negated ^ the attribute value is the enable bit.
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Meinersbur wrote:

Add explantion that its ternary logic: If BoolAttr is unset, don't add any node.

https://github.com/llvm/llvm-project/pull/213902