[Mlir-commits] [mlir] [mlir]use correct iterator when eraseOp (PR #83444)

[Congcong Cai]

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@@ -229,14 +229,14 @@ void RewriterBase::eraseOp(Operation *op) {
       // until the region is empty. (The block graph could be disconnected.)
       while (!r.empty()) {
         SmallVector<Block *> erasedBlocks;
-        for (Block *b : llvm::post_order(&r.front())) {
+        for (Block &b : llvm::reverse(r.getBlocks())) {
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HerrCai0907 wrote:

The reason is some success in block is nullptr, it is already dereferenced.
If we want to keep post order, then we can pass a set including nullptr to avoid visit broken success.

https://github.com/llvm/llvm-project/pull/83444