[ADT] Fix a memory leak in SmallDenseMap

[kazutakahirata]

Tmp.moveFrom(*this); about 10 lines above leaves *this in a zombie
state with a bucket array still allocated. This patch fixes the
memory leak by calling deallocateBuckets().

[llvmbot]

@llvm/pr-subscribers-llvm-adt

Author: Kazu Hirata (kazutakahirata)

Changes

Tmp.moveFrom(*this); about 10 lines above leaves *this in a zombie
state with a bucket array still allocated. This patch fixes the
memory leak by calling deallocateBuckets().

---

Full diff: https://github.com/llvm/llvm-project/pull/168011.diff

1 Files Affected:

• (modified) llvm/include/llvm/ADT/DenseMap.h (+1)

diff --git a/llvm/include/llvm/ADT/DenseMap.h b/llvm/include/llvm/ADT/DenseMap.h
index 9d61a91631fab..333bbcb9399ce 100644
--- a/llvm/include/llvm/ADT/DenseMap.h
+++ b/llvm/include/llvm/ADT/DenseMap.h
@@ -1122,6 +1122,7 @@ class SmallDenseMap
       Tmp.Small = false;
       Tmp.getLargeRep()->NumBuckets = 0;
     } else {
+      deallocateBuckets();
       Small = false;
       NumTombstones = 0;
       *getLargeRep() = std::move(*Tmp.getLargeRep());