[ADT] Reduce code duplication in SmallDenseMap (NFC)

llvm/include/llvm/ADT/DenseMap.h

@@ -1009,21 +1009,13 @@ class SmallDenseMap
   void copyFrom(const SmallDenseMap &other) {
     this->destroyAll();
     deallocateBuckets();
-    Small = true;
-    if (other.getNumBuckets() > InlineBuckets) {
-      Small = false;
-      new (getLargeRep()) LargeRep(allocateBuckets(other.getNumBuckets()));
-    }
+    allocateBuckets(other.getNumBuckets());
     this->BaseT::copyFrom(other);
   }
 
   void init(unsigned InitNumEntries) {
     auto InitBuckets = BaseT::getMinBucketToReserveForEntries(InitNumEntries);
-    Small = true;
-    if (InitBuckets > InlineBuckets) {
-      Small = false;
-      new (getLargeRep()) LargeRep(allocateBuckets(InitBuckets));
-    }
+    allocateBuckets(InitBuckets);
     this->BaseT::initEmpty();
   }
 
@@ -1057,21 +1049,14 @@ class SmallDenseMap
       // AtLeast == InlineBuckets can happen if there are many tombstones,
       // and grow() is used to remove them. Usually we always switch to the
       // large rep here.
-      if (AtLeast > InlineBuckets) {
-        Small = false;
-        new (getLargeRep()) LargeRep(allocateBuckets(AtLeast));
-      }
+      allocateBuckets(AtLeast);
       this->moveFromOldBuckets(llvm::make_range(TmpBegin, TmpEnd));
       return;
     }
 
     LargeRep OldRep = std::move(*getLargeRep());
     getLargeRep()->~LargeRep();
-    if (AtLeast <= InlineBuckets) {
-      Small = true;
-    } else {
-      new (getLargeRep()) LargeRep(allocateBuckets(AtLeast));
-    }
+    allocateBuckets(AtLeast);
 
     this->moveFromOldBuckets(OldRep.buckets());
 
@@ -1166,12 +1151,15 @@ class SmallDenseMap
     getLargeRep()->~LargeRep();
   }
 
-  LargeRep allocateBuckets(unsigned Num) {
-    assert(Num > InlineBuckets && "Must allocate more buckets than are inline");
-    LargeRep Rep = {static_cast<BucketT *>(allocate_buffer(
-                        sizeof(BucketT) * Num, alignof(BucketT))),
-                    Num};
-    return Rep;
+  void allocateBuckets(unsigned Num) {
+    if (Num <= InlineBuckets) {
+      Small = true;
+    } else {
+      Small = false;
+      BucketT *NewBuckets = static_cast<BucketT *>(
+          allocate_buffer(sizeof(BucketT) * Num, alignof(BucketT)));
+      new (getLargeRep()) LargeRep{NewBuckets, Num};
+    }
   }
 };