Compiler: continuing refactoring

Moving the arena memory allocation mechanism into it's own class as
a prelude to cleaning up the MIR and LIR data structures.

Reworked bit vector as a class using placement new w/ the arena
allocator.

Reworked GrowableList as a class template using the new arena
allocator and renamed to GrowableArray.

Change-Id: I639c4c08abe068094cae2649e04f58c8addd0015
diff --git a/src/compiler/dex/growable_array.h b/src/compiler/dex/growable_array.h
new file mode 100644
index 0000000..eb865d5
--- /dev/null
+++ b/src/compiler/dex/growable_array.h
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_SRC_COMPILER_DEX_GROWABLE_LIST_H_
+#define ART_SRC_COMPILER_DEX_GROWABLE_LIST_H_
+
+#include <stdint.h>
+#include <stddef.h>
+#include "compiler_enums.h"
+#include "arena_allocator.h"
+
+namespace art {
+
+struct CompilationUnit;
+
+// Type of growable list for memory tuning.
+enum OatListKind {
+  kGrowableArrayMisc = 0,
+  kGrowableArrayBlockList,
+  kGrowableArraySSAtoDalvikMap,
+  kGrowableArrayDfsOrder,
+  kGrowableArrayDfsPostOrder,
+  kGrowableArrayDomPostOrderTraversal,
+  kGrowableArrayThrowLaunchPads,
+  kGrowableArraySuspendLaunchPads,
+  kGrowableArraySwitchTables,
+  kGrowableArrayFillArrayData,
+  kGrowableArraySuccessorBlocks,
+  kGrowableArrayPredecessors,
+  kGNumListKinds
+};
+
+template<typename T>
+class GrowableArray {
+  public:
+
+    class Iterator {
+      public:
+        Iterator(GrowableArray* g_list)
+          : idx_(0),
+            g_list_(g_list) {};
+
+        // NOTE: returns 0/NULL when no next.
+        // TODO: redo to make usage consistent with other iterators.
+        T Next() {
+          if (idx_ >= g_list_->Size()) {
+            return 0;
+          } else {
+            return g_list_->Get(idx_++);
+          }
+        }
+
+        void Reset() {
+          idx_ = 0;
+        }
+
+        static void* operator new(size_t size, ArenaAllocator* arena) {
+          return arena->NewMem(sizeof(GrowableArray::Iterator), true, ArenaAllocator::kAllocGrowableArray);
+        };
+        static void operator delete(void* p) {};  // Nop.
+
+      private:
+        size_t idx_;
+        GrowableArray* const g_list_;
+    };
+
+    GrowableArray(ArenaAllocator* arena, size_t init_length, OatListKind kind = kGrowableArrayMisc)
+      : arena_(arena),
+        num_allocated_(0),
+        num_used_(0),
+        kind_(kind) {
+      elem_list_ = static_cast<T*>(arena_->NewMem(sizeof(T) * init_length, true,
+                                                 ArenaAllocator::kAllocGrowableArray));
+      // TODO: Collect detailed memory usage stats by list kind.
+    };
+
+
+    // Expand the list size to at least new length.
+    void Resize(size_t new_length) {
+      if (new_length <= num_allocated_) return;
+      size_t target_length = (num_allocated_ < 128) ? num_allocated_ << 1 : num_allocated_ + 128;
+      if (new_length > target_length) {
+         target_length = new_length;
+      }
+      T* new_array = static_cast<T*>(arena_->NewMem(sizeof(T) * target_length, true,
+                                                    ArenaAllocator::kAllocGrowableArray));
+      memcpy(new_array, elem_list_, sizeof(T) * num_allocated_);
+      // TODO: Collect stats on wasted resize memory.
+      num_allocated_ = target_length;
+      elem_list_ = new_array;
+    };
+
+    // NOTE: does not return storage, just resets use count.
+    void Reset() {
+      num_used_ = 0;
+    }
+
+    // Insert an element to the end of a list, resizing if necessary.
+    void Insert(T elem) {
+      if (num_used_ == num_allocated_) {
+        Resize(num_used_ + 1);
+      }
+      elem_list_[num_used_++] = elem;
+    };
+
+    T Get(size_t index) const {
+      DCHECK_LT(index, num_used_);
+      return elem_list_[index];
+    };
+
+    // Overwrite existing element at position index.  List must be large enough.
+    void Put(size_t index, T elem) {
+      DCHECK_LT(index, num_used_);
+      elem_list_[index] = elem;
+    }
+
+    void Increment(size_t index) {
+      DCHECK_LT(index, num_used_);
+      elem_list_[index]++;
+    }
+
+    void Delete(T element) {
+      bool found = false;
+      for (size_t i = 0; i < num_used_ - 1; i++) {
+        if (!found && elem_list_[i] == element) {
+          found = true;
+        }
+        if (found) {
+          elem_list_[i] = elem_list_[i+1];
+        }
+      }
+      // We should either have found the element, or it was the last (unscanned) element.
+      DCHECK(found || (element == elem_list_[num_used_ - 1]));
+      num_used_--;
+    };
+
+    size_t GetNumAllocated() const { return num_allocated_; }
+
+    size_t Size() const { return num_used_; }
+
+    T* GetRawStorage() const { return elem_list_; }
+
+    static void* operator new(size_t size, ArenaAllocator* arena) {
+      return arena->NewMem(sizeof(GrowableArray<T>), true, ArenaAllocator::kAllocGrowableArray);
+    };
+    static void operator delete(void* p) {};  // Nop.
+
+  private:
+    ArenaAllocator* const arena_;
+    size_t num_allocated_;
+    size_t num_used_;
+    OatListKind kind_;
+    T* elem_list_;
+};
+
+}  // namespace art
+
+#endif  // ART_SRC_COMPILER_DEX_GROWABLE_LIST_H_