[Mlir-commits] [mlir] [MLIR] `remove-dead-values` and RegionBranchOp canononicalizations fixes around the `IsolatedFromAbove` ops (PR #224831)

[Matthias Springer]

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@@ -48,6 +48,15 @@ ChangeResult Liveness::meet(const AbstractSparseLattice &other) {
 // LivenessAnalysis
 //===----------------------------------------------------------------------===//
 
+LogicalResult LivenessAnalysis::initialize(Operation *top) {
+  // Users outside the analysis root are not visited. Mark all root results live
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matthias-springer wrote:

Why is this necessary? Why would the analysis not visit an operation? Doesn't that mean that the operation is not reachable, and thus dead?

https://github.com/llvm/llvm-project/pull/224831