[llvm] [ADT] Use StorageT for temporary storage in DenseMapBase::grow (NFC) (PR #228802)

[Fangrui Song via llvm-commits]

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@@ -1111,27 +1094,28 @@ class DenseMapBase : public DebugEpochBase {
     return llvm::densemap::detail::hasherFor<KeyT, KeyInfoT>();
   }
 
-  // Move key/value from Other to *this.
-  // Other is left in a valid but empty state.
-  LLVM_ATTRIBUTE_NOINLINE void moveFrom(DenseMapBase &Other) {
-    assert(getNumEntries() == 0 && "moveFrom requires an empty destination");
-    BucketT *OtherB = Other.getBuckets();
-    UsedT *OtherU = Other.getUsed();
-    const unsigned E = Other.getNumBuckets();
-    UsedT *U = getUsed();
-    BucketT *B = getBuckets();
-    const unsigned Mask = getNumBuckets() - 1;
-    llvm::densemap::detail::forEachUsed(OtherU, E, [&](unsigned I) {
+  // Move key/value from Src to Dst.
+  // Src is left in a valid but empty state.
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MaskRay wrote:

Is this comment still correct?

https://github.com/llvm/llvm-project/pull/228802