[Mlir-commits] [mlir] [mlir][docs] Add poison example to canonicalization section (PR #192782)

[Renato Golin]

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@@ -96,6 +96,8 @@ canonicalizations include:
   rewriting `tensor.insert_slice(%src, tensor.cast(%dst))` (where the cast
   converts from `tensor<5xf32>` to `tensor<?xf32>`) as
   `tensor.cast(tensor.insert_slice(%src, %dst))`.
+* Replacing poisoned results with `ub.poison`. E.g., replacing
+  `arith.divsi(%c5, %c2, exact)` with `ub.poison`.
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rengolin wrote:

do you mean `%c2` as `arith.constant 0`?

At least two cases here:
* `div x, 0` -> `poison`
* `op poison, ...` -> `poison`

https://github.com/llvm/llvm-project/pull/192782