[llvm] [GVN] Improve processBlock for instruction erasure (PR #131753)

[Nikita Popov via llvm-commits]

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@@ -729,8 +728,9 @@ void GVNPass::ValueTable::erase(Value *V) {
 /// verifyRemoved - Verify that the value is removed from all internal data
 /// structures.
 void GVNPass::ValueTable::verifyRemoved(const Value *V) const {
-  assert(!ValueNumbering.contains(V) &&
-         "Inst still occurs in value numbering map!");
+  if (V != nullptr)
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nikic wrote:

Why is this change necessary?

https://github.com/llvm/llvm-project/pull/131753