[Mlir-commits] [mlir] [mlir][CSE] Pre-process trivially dead ops (NFC) (PR #191135)

[Mehdi Amini]

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@@ -308,7 +301,16 @@ LogicalResult CSEDriver::simplifyOperation(ScopedMapTy &knownValues,
 
 void CSEDriver::simplifyBlock(ScopedMapTy &knownValues, Block *bb,
                               bool hasSSADominance) {
-  for (auto &op : *bb) {
+  for (auto &op : llvm::make_early_inc_range(*bb)) {
+    // If the operation is already trivially dead just add it to the erase list.
+    // This also avoids calling `simplifyRegion` on dead region ops
+    // unnecessarily.
+    if (isOpTriviallyDead(&op)) {
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joker-eph wrote:

I'm not always clear on how not eagerly deleting operation isn't just making CSE miss on simplification opportunities, but this patch looks good within the current flow.

https://github.com/llvm/llvm-project/pull/191135