[Mlir-commits] [mlir] [mlir][Vector] Improve `vector.mask` verifier (PR #139823)

[Andrzej Warzyński]

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@@ -2482,8 +2482,13 @@ def Vector_MaskOp : Vector_Op<"mask", [
     masked. Values used within the region are captured from above. Only one
     *maskable* operation can be masked with a `vector.mask` operation at a time.
     An operation is *maskable* if it implements the `MaskableOpInterface`. The
-    terminator yields all results of the maskable operation to the result of
-    this operation.
+    terminator yields all results from the maskable operation to the result of
+    this operation. No other values are allowed to be yielded.
+
+    An empty `vector.mask` operation is considered ill-formed but legal to
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banach-space wrote:

I don't want come across as nit-picking, but what does "ill-formed" mean? To me, the sentence that follows suggests that empty masks are totally fine, no? 

https://github.com/llvm/llvm-project/pull/139823