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

[Michael Kruse via llvm-commits]

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@@ -112,14 +112,14 @@ namespace llvm {
 
   /// Check whether a string looks like an old loop attachment tag.
   inline bool mayBeOldLoopAttachmentTag(StringRef Name) {
-    // "llvm.loop.distribute.enable" and "llvm.loop.vectorize.enable" are
-    // intentionally included: the current single-operand form shares the tag
-    // with the removed two-operand form (!{!"...", i1 X}), so we can only
-    // decide by inspecting the operands, which happens in
-    // upgradeLoopArgument().
+    // The enable tags below are intentionally included: the current
+    // single-operand form shares the tag with the removed two-operand form
+    // (!{!"...", i1 X}), so we can only decide by inspecting the operands,
+    // which happens in upgradeLoopArgument().
     return Name.starts_with("llvm.vectorizer.") ||
            Name == "llvm.loop.distribute.enable" ||
-           Name == "llvm.loop.vectorize.enable";
+           Name == "llvm.loop.vectorize.enable" ||
+           Name == "llvm.loop.vectorize.predicate.enable";
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Meinersbur wrote:

Use the `OldBooleanLoopTags` list here?

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