1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ART_COMPILER_OPTIMIZING_NODES_ARM_H_
18#define ART_COMPILER_OPTIMIZING_NODES_ARM_H_
19
20namespace art {
21
22class HArmDexCacheArraysBase FINAL : public HExpression<0> {
23 public:
24  explicit HArmDexCacheArraysBase(const DexFile& dex_file)
25      : HExpression(Primitive::kPrimInt, SideEffects::None(), kNoDexPc),
26        dex_file_(&dex_file),
27        element_offset_(static_cast<size_t>(-1)) { }
28
29  bool CanBeMoved() const OVERRIDE { return true; }
30
31  void UpdateElementOffset(size_t element_offset) {
32    // Use the lowest offset from the requested elements so that all offsets from
33    // this base are non-negative because our assemblers emit negative-offset loads
34    // as a sequence of two or more instructions. (However, positive offsets beyond
35    // 4KiB also require two or more instructions, so this simple heuristic could
36    // be improved for cases where there is a dense cluster of elements far from
37    // the lowest offset. This is expected to be rare enough though, so we choose
38    // not to spend compile time on elaborate calculations.)
39    element_offset_ = std::min(element_offset_, element_offset);
40  }
41
42  const DexFile& GetDexFile() const {
43    return *dex_file_;
44  }
45
46  size_t GetElementOffset() const {
47    return element_offset_;
48  }
49
50  DECLARE_INSTRUCTION(ArmDexCacheArraysBase);
51
52 private:
53  const DexFile* dex_file_;
54  size_t element_offset_;
55
56  DISALLOW_COPY_AND_ASSIGN(HArmDexCacheArraysBase);
57};
58
59}  // namespace art
60
61#endif  // ART_COMPILER_OPTIMIZING_NODES_ARM_H_
62