Ensure -mcpu=xscale works for arm targets, after rL252903 and rL252904

[oota-llvm.git] / include / llvm / Support / Recycler.h

diff --git a/include/llvm/Support/Recycler.h b/include/llvm/Support/Recycler.h
index 8d4dc4ca4069306f9b93301e003664c600eb496e..a38050d81903ac24b7b180a3c9d118f4e37a9d6d 100644 (file)
--- a/include/llvm/Support/Recycler.h
+++ b/include/llvm/Support/Recycler.h
@@ -15,62 +15,77 @@
 #ifndef LLVM_SUPPORT_RECYCLER_H
 #define LLVM_SUPPORT_RECYCLER_H
 
-#include "llvm/ADT/alist_node.h"
+#include "llvm/ADT/ilist.h"
+#include "llvm/Support/AlignOf.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/ErrorHandling.h"
+#include <cassert>
 
 namespace llvm {
 
 /// PrintRecyclingAllocatorStats - Helper for RecyclingAllocator for
 /// printing statistics.
 ///
-void PrintRecyclerStats(size_t LargestTypeSize, size_t FreeListSize);
+void PrintRecyclerStats(size_t Size, size_t Align, size_t FreeListSize);
 
 /// Recycler - This class manages a linked-list of deallocated nodes
 /// and facilitates reusing deallocated memory in place of allocating
-/// new memory. The objects it allocates are stored in alist_node
-/// containers, so they may be used in alists.
+/// new memory.
 ///
-template<class T, class LargestT = T>
+template<class T, size_t Size = sizeof(T), size_t Align = AlignOf<T>::Alignment>
 class Recycler {
-  typedef alist_node<T, LargestT> NodeTy;
-
-  /// FreeListTraits - ilist traits for FreeList.
-  ///
-  struct FreeListTraits : ilist_traits<alist_node<T, LargestT> > {
-    NodeTy &getSentinel() { return this->Sentinel; }
+  struct FreeNode {
+    FreeNode *Next;
   };
 
-  /// FreeList - Doubly-linked list of nodes that have deleted contents and
-  /// are not in active use.
-  ///
-  iplist<NodeTy, FreeListTraits> FreeList;
+  /// List of nodes that have deleted contents and are not in active use.
+  FreeNode *FreeList = nullptr;
 
-  /// CreateNewNode - Allocate a new node object and initialize its
-  /// prev and next pointers to 0.
-  ///
-  template<class AllocatorType>
-  NodeTy *CreateNewNode(AllocatorType &Allocator) {
-    // Note that we're calling new on the *node*, to initialize its
-    // Next/Prev pointers, not new on the end-user object.
-    return new (Allocator.Allocate<NodeTy>()) NodeTy();
+  FreeNode *pop_val() {
+    auto *Val = FreeList;
+    FreeList = FreeList->Next;
+    return Val;
+  }
+
+  void push(FreeNode *N) {
+    N->Next = FreeList;
+    FreeList = N;
   }
 
 public:
-  ~Recycler() { assert(FreeList.empty()); }
+  ~Recycler() {
+    // If this fails, either the callee has lost track of some allocation,
+    // or the callee isn't tracking allocations and should just call
+    // clear() before deleting the Recycler.
+    assert(!FreeList && "Non-empty recycler deleted!");
+  }
 
+  /// clear - Release all the tracked allocations to the allocator. The
+  /// recycler must be free of any tracked allocations before being
+  /// deleted; calling clear is one way to ensure this.
   template<class AllocatorType>
   void clear(AllocatorType &Allocator) {
-    while (!FreeList.empty())
-      Allocator.Deallocate(FreeList.remove(FreeList.begin()));
+    while (FreeList) {
+      T *t = reinterpret_cast<T *>(pop_val());
+      Allocator.Deallocate(t);
+    }
   }
 
+  /// Special case for BumpPtrAllocator which has an empty Deallocate()
+  /// function.
+  ///
+  /// There is no need to traverse the free list, pulling all the objects into
+  /// cache.
+  void clear(BumpPtrAllocator &) { FreeList = nullptr; }
+
   template<class SubClass, class AllocatorType>
   SubClass *Allocate(AllocatorType &Allocator) {
-    NodeTy *N = !FreeList.empty() ?
-                FreeList.remove(FreeList.front()) :
-                CreateNewNode(Allocator);
-    assert(N->getPrev() == 0);
-    assert(N->getNext() == 0);
-    return N->getElement((SubClass*)0);
+    static_assert(AlignOf<SubClass>::Alignment <= Align,
+                  "Recycler allocation alignment is less than object align!");
+    static_assert(sizeof(SubClass) <= Size,
+                  "Recycler allocation size is less than object size!");
+    return FreeList ? reinterpret_cast<SubClass *>(pop_val())
+                    : static_cast<SubClass *>(Allocator.Allocate(Size, Align));
   }
 
   template<class AllocatorType>
@@ -79,18 +94,21 @@ public:
   }
 
   template<class SubClass, class AllocatorType>
-  void Deallocate(AllocatorType &Allocator, SubClass* Element) {
-    NodeTy *N = NodeTy::getNode(Element);
-    assert(N->getPrev() == 0);
-    assert(N->getNext() == 0);
-    FreeList.push_front(N);
+  void Deallocate(AllocatorType & /*Allocator*/, SubClass* Element) {
+    push(reinterpret_cast<FreeNode *>(Element));
   }
 
-  void PrintStats() {
-    PrintRecyclerStats(sizeof(LargestT), FreeList.size());
-  }
+  void PrintStats();
 };
 
+template <class T, size_t Size, size_t Align>
+void Recycler<T, Size, Align>::PrintStats() {
+  size_t S = 0;
+  for (auto *I = FreeList; I; I = I->Next)
+    ++S;
+  PrintRecyclerStats(Size, Align, S);
+}
+
 }
 
 #endif