[llvm] [ADT] Exit doFind on an empty map, not just an unallocated one (PR #220294)

[via llvm-commits]

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@@ -721,9 +721,10 @@ class DenseMapBase : public DebugEpochBase {
 
   template <typename LookupKeyT>
   const BucketT *doFind(const LookupKeyT &Val) const {
-    auto [BucketsPtr, U, NumBuckets] = getRep();
-    if (NumBuckets == 0)
+    // Tighter than NumBuckets == 0: catches emptied and small-mode maps.
+    if (getNumEntries() == 0)
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khaki3 wrote:

Thanks. I've applied it.

https://github.com/llvm/llvm-project/pull/220294