Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/llvm/ADT/FoldingSet.h b/linux-x64/clang/include/llvm/ADT/FoldingSet.h
index d5837e5..fb1cb03 100644
--- a/linux-x64/clang/include/llvm/ADT/FoldingSet.h
+++ b/linux-x64/clang/include/llvm/ADT/FoldingSet.h
@@ -85,17 +85,17 @@
 ///
 ///    MyNode *M = MyFoldingSet.FindNodeOrInsertPos(ID, InsertPoint);
 ///
-/// If found then M with be non-NULL, else InsertPoint will point to where it
+/// If found then M will be non-NULL, else InsertPoint will point to where it
 /// should be inserted using InsertNode.
 ///
-/// 3) If you get a NULL result from FindNodeOrInsertPos then you can as a new
-/// node with FindNodeOrInsertPos;
+/// 3) If you get a NULL result from FindNodeOrInsertPos then you can insert a
+/// new node with InsertNode;
 ///
-///    InsertNode(N, InsertPoint);
+///    MyFoldingSet.InsertNode(M, InsertPoint);
 ///
 /// 4) Finally, if you want to remove a node from the folding set call;
 ///
-///    bool WasRemoved = RemoveNode(N);
+///    bool WasRemoved = MyFoldingSet.RemoveNode(M);
 ///
 /// The result indicates whether the node existed in the folding set.
 
@@ -110,8 +110,6 @@
 /// back to the bucket to facilitate node removal.
 ///
 class FoldingSetBase {
-  virtual void anchor(); // Out of line virtual method.
-
 protected:
   /// Buckets - Array of bucket chains.
   void **Buckets;
@@ -154,11 +152,6 @@
   /// empty - Returns true if there are no nodes in the folding set.
   bool empty() const { return NumNodes == 0; }
 
-  /// reserve - Increase the number of buckets such that adding the
-  /// EltCount-th node won't cause a rebucket operation. reserve is permitted
-  /// to allocate more space than requested by EltCount.
-  void reserve(unsigned EltCount);
-
   /// capacity - Returns the number of nodes permitted in the folding set
   /// before a rebucket operation is performed.
   unsigned capacity() {
@@ -167,32 +160,46 @@
     return NumBuckets * 2;
   }
 
+protected:
+  /// Functions provided by the derived class to compute folding properties.
+  /// This is effectively a vtable for FoldingSetBase, except that we don't
+  /// actually store a pointer to it in the object.
+  struct FoldingSetInfo {
+    /// GetNodeProfile - Instantiations of the FoldingSet template implement
+    /// this function to gather data bits for the given node.
+    void (*GetNodeProfile)(const FoldingSetBase *Self, Node *N,
+                           FoldingSetNodeID &ID);
+
+    /// NodeEquals - Instantiations of the FoldingSet template implement
+    /// this function to compare the given node with the given ID.
+    bool (*NodeEquals)(const FoldingSetBase *Self, Node *N,
+                       const FoldingSetNodeID &ID, unsigned IDHash,
+                       FoldingSetNodeID &TempID);
+
+    /// ComputeNodeHash - Instantiations of the FoldingSet template implement
+    /// this function to compute a hash value for the given node.
+    unsigned (*ComputeNodeHash)(const FoldingSetBase *Self, Node *N,
+                                FoldingSetNodeID &TempID);
+  };
+
 private:
   /// GrowHashTable - Double the size of the hash table and rehash everything.
-  void GrowHashTable();
+  void GrowHashTable(const FoldingSetInfo &Info);
 
   /// GrowBucketCount - resize the hash table and rehash everything.
   /// NewBucketCount must be a power of two, and must be greater than the old
   /// bucket count.
-  void GrowBucketCount(unsigned NewBucketCount);
+  void GrowBucketCount(unsigned NewBucketCount, const FoldingSetInfo &Info);
 
 protected:
-  /// GetNodeProfile - Instantiations of the FoldingSet template implement
-  /// this function to gather data bits for the given node.
-  virtual void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const = 0;
-
-  /// NodeEquals - Instantiations of the FoldingSet template implement
-  /// this function to compare the given node with the given ID.
-  virtual bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash,
-                          FoldingSetNodeID &TempID) const=0;
-
-  /// ComputeNodeHash - Instantiations of the FoldingSet template implement
-  /// this function to compute a hash value for the given node.
-  virtual unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const = 0;
-
   // The below methods are protected to encourage subclasses to provide a more
   // type-safe API.
 
+  /// reserve - Increase the number of buckets such that adding the
+  /// EltCount-th node won't cause a rebucket operation. reserve is permitted
+  /// to allocate more space than requested by EltCount.
+  void reserve(unsigned EltCount, const FoldingSetInfo &Info);
+
   /// RemoveNode - Remove a node from the folding set, returning true if one
   /// was removed or false if the node was not in the folding set.
   bool RemoveNode(Node *N);
@@ -200,17 +207,18 @@
   /// GetOrInsertNode - If there is an existing simple Node exactly
   /// equal to the specified node, return it.  Otherwise, insert 'N' and return
   /// it instead.
-  Node *GetOrInsertNode(Node *N);
+  Node *GetOrInsertNode(Node *N, const FoldingSetInfo &Info);
 
   /// FindNodeOrInsertPos - Look up the node specified by ID.  If it exists,
   /// return it.  If not, return the insertion token that will make insertion
   /// faster.
-  Node *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
+  Node *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos,
+                            const FoldingSetInfo &Info);
 
   /// InsertNode - Insert the specified node into the folding set, knowing that
   /// it is not already in the folding set.  InsertPos must be obtained from
   /// FindNodeOrInsertPos.
-  void InsertNode(Node *N, void *InsertPos);
+  void InsertNode(Node *N, void *InsertPos, const FoldingSetInfo &Info);
 };
 
 //===----------------------------------------------------------------------===//
@@ -397,7 +405,7 @@
 //===----------------------------------------------------------------------===//
 /// FoldingSetImpl - An implementation detail that lets us share code between
 /// FoldingSet and ContextualFoldingSet.
-template <class T> class FoldingSetImpl : public FoldingSetBase {
+template <class Derived, class T> class FoldingSetImpl : public FoldingSetBase {
 protected:
   explicit FoldingSetImpl(unsigned Log2InitSize)
       : FoldingSetBase(Log2InitSize) {}
@@ -427,29 +435,40 @@
     return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true);
   }
 
+  /// reserve - Increase the number of buckets such that adding the
+  /// EltCount-th node won't cause a rebucket operation. reserve is permitted
+  /// to allocate more space than requested by EltCount.
+  void reserve(unsigned EltCount) {
+    return FoldingSetBase::reserve(EltCount, Derived::getFoldingSetInfo());
+  }
+
   /// RemoveNode - Remove a node from the folding set, returning true if one
   /// was removed or false if the node was not in the folding set.
-  bool RemoveNode(T *N) { return FoldingSetBase::RemoveNode(N); }
+  bool RemoveNode(T *N) {
+    return FoldingSetBase::RemoveNode(N);
+  }
 
   /// GetOrInsertNode - If there is an existing simple Node exactly
   /// equal to the specified node, return it.  Otherwise, insert 'N' and
   /// return it instead.
   T *GetOrInsertNode(T *N) {
-    return static_cast<T *>(FoldingSetBase::GetOrInsertNode(N));
+    return static_cast<T *>(
+        FoldingSetBase::GetOrInsertNode(N, Derived::getFoldingSetInfo()));
   }
 
   /// FindNodeOrInsertPos - Look up the node specified by ID.  If it exists,
   /// return it.  If not, return the insertion token that will make insertion
   /// faster.
   T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) {
-    return static_cast<T *>(FoldingSetBase::FindNodeOrInsertPos(ID, InsertPos));
+    return static_cast<T *>(FoldingSetBase::FindNodeOrInsertPos(
+        ID, InsertPos, Derived::getFoldingSetInfo()));
   }
 
   /// InsertNode - Insert the specified node into the folding set, knowing that
   /// it is not already in the folding set.  InsertPos must be obtained from
   /// FindNodeOrInsertPos.
   void InsertNode(T *N, void *InsertPos) {
-    FoldingSetBase::InsertNode(N, InsertPos);
+    FoldingSetBase::InsertNode(N, InsertPos, Derived::getFoldingSetInfo());
   }
 
   /// InsertNode - Insert the specified node into the folding set, knowing that
@@ -470,32 +489,43 @@
 /// moved-from state is not a valid state for anything other than
 /// move-assigning and destroying. This is primarily to enable movable APIs
 /// that incorporate these objects.
-template <class T> class FoldingSet final : public FoldingSetImpl<T> {
-  using Super = FoldingSetImpl<T>;
+template <class T>
+class FoldingSet : public FoldingSetImpl<FoldingSet<T>, T> {
+  using Super = FoldingSetImpl<FoldingSet, T>;
   using Node = typename Super::Node;
 
-  /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a
+  /// GetNodeProfile - Each instantiation of the FoldingSet needs to provide a
   /// way to convert nodes into a unique specifier.
-  void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const override {
+  static void GetNodeProfile(const FoldingSetBase *, Node *N,
+                             FoldingSetNodeID &ID) {
     T *TN = static_cast<T *>(N);
     FoldingSetTrait<T>::Profile(*TN, ID);
   }
 
   /// NodeEquals - Instantiations may optionally provide a way to compare a
   /// node with a specified ID.
-  bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash,
-                  FoldingSetNodeID &TempID) const override {
+  static bool NodeEquals(const FoldingSetBase *, Node *N,
+                         const FoldingSetNodeID &ID, unsigned IDHash,
+                         FoldingSetNodeID &TempID) {
     T *TN = static_cast<T *>(N);
     return FoldingSetTrait<T>::Equals(*TN, ID, IDHash, TempID);
   }
 
   /// ComputeNodeHash - Instantiations may optionally provide a way to compute a
   /// hash value directly from a node.
-  unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const override {
+  static unsigned ComputeNodeHash(const FoldingSetBase *, Node *N,
+                                  FoldingSetNodeID &TempID) {
     T *TN = static_cast<T *>(N);
     return FoldingSetTrait<T>::ComputeHash(*TN, TempID);
   }
 
+  static const FoldingSetBase::FoldingSetInfo &getFoldingSetInfo() {
+    static constexpr FoldingSetBase::FoldingSetInfo Info = {
+        GetNodeProfile, NodeEquals, ComputeNodeHash};
+    return Info;
+  }
+  friend Super;
+
 public:
   explicit FoldingSet(unsigned Log2InitSize = 6) : Super(Log2InitSize) {}
   FoldingSet(FoldingSet &&Arg) = default;
@@ -512,36 +542,52 @@
 /// function with signature
 ///   void Profile(FoldingSetNodeID &, Ctx);
 template <class T, class Ctx>
-class ContextualFoldingSet final : public FoldingSetImpl<T> {
+class ContextualFoldingSet
+    : public FoldingSetImpl<ContextualFoldingSet<T, Ctx>, T> {
   // Unfortunately, this can't derive from FoldingSet<T> because the
   // construction of the vtable for FoldingSet<T> requires
   // FoldingSet<T>::GetNodeProfile to be instantiated, which in turn
   // requires a single-argument T::Profile().
 
-  using Super = FoldingSetImpl<T>;
+  using Super = FoldingSetImpl<ContextualFoldingSet, T>;
   using Node = typename Super::Node;
 
   Ctx Context;
 
+  static const Ctx &getContext(const FoldingSetBase *Base) {
+    return static_cast<const ContextualFoldingSet*>(Base)->Context;
+  }
+
   /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a
   /// way to convert nodes into a unique specifier.
-  void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const override {
+  static void GetNodeProfile(const FoldingSetBase *Base, Node *N,
+                             FoldingSetNodeID &ID) {
     T *TN = static_cast<T *>(N);
-    ContextualFoldingSetTrait<T, Ctx>::Profile(*TN, ID, Context);
+    ContextualFoldingSetTrait<T, Ctx>::Profile(*TN, ID, getContext(Base));
   }
 
-  bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash,
-                  FoldingSetNodeID &TempID) const override {
+  static bool NodeEquals(const FoldingSetBase *Base, Node *N,
+                         const FoldingSetNodeID &ID, unsigned IDHash,
+                         FoldingSetNodeID &TempID) {
     T *TN = static_cast<T *>(N);
     return ContextualFoldingSetTrait<T, Ctx>::Equals(*TN, ID, IDHash, TempID,
-                                                     Context);
+                                                     getContext(Base));
   }
 
-  unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const override {
+  static unsigned ComputeNodeHash(const FoldingSetBase *Base, Node *N,
+                                  FoldingSetNodeID &TempID) {
     T *TN = static_cast<T *>(N);
-    return ContextualFoldingSetTrait<T, Ctx>::ComputeHash(*TN, TempID, Context);
+    return ContextualFoldingSetTrait<T, Ctx>::ComputeHash(*TN, TempID,
+                                                          getContext(Base));
   }
 
+  static const FoldingSetBase::FoldingSetInfo &getFoldingSetInfo() {
+    static constexpr FoldingSetBase::FoldingSetInfo Info = {
+        GetNodeProfile, NodeEquals, ComputeNodeHash};
+    return Info;
+  }
+  friend Super;
+
 public:
   explicit ContextualFoldingSet(Ctx Context, unsigned Log2InitSize = 6)
       : Super(Log2InitSize), Context(Context) {}