1/*
2 * Copyright (C) 2011 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_RUNTIME_ARCH_INSTRUCTION_SET_FEATURES_H_
18#define ART_RUNTIME_ARCH_INSTRUCTION_SET_FEATURES_H_
19
20#include <ostream>
21#include <vector>
22
23#include "base/macros.h"
24#include "instruction_set.h"
25
26namespace art {
27
28class ArmInstructionSetFeatures;
29class Arm64InstructionSetFeatures;
30class MipsInstructionSetFeatures;
31class Mips64InstructionSetFeatures;
32class X86InstructionSetFeatures;
33class X86_64InstructionSetFeatures;
34
35// Abstraction used to describe features of a different instruction sets.
36class InstructionSetFeatures {
37 public:
38  // Process a CPU variant string for the given ISA and create an InstructionSetFeatures.
39  static const InstructionSetFeatures* FromVariant(InstructionSet isa,
40                                                   const std::string& variant,
41                                                   std::string* error_msg);
42
43  // Parse a bitmap for the given isa and create an InstructionSetFeatures.
44  static const InstructionSetFeatures* FromBitmap(InstructionSet isa, uint32_t bitmap);
45
46  // Turn C pre-processor #defines into the equivalent instruction set features for kRuntimeISA.
47  static const InstructionSetFeatures* FromCppDefines();
48
49  // Process /proc/cpuinfo and use kRuntimeISA to produce InstructionSetFeatures.
50  static const InstructionSetFeatures* FromCpuInfo();
51
52  // Process the auxiliary vector AT_HWCAP entry and use kRuntimeISA to produce
53  // InstructionSetFeatures.
54  static const InstructionSetFeatures* FromHwcap();
55
56  // Use assembly tests of the current runtime (ie kRuntimeISA) to determine the
57  // InstructionSetFeatures. This works around kernel bugs in AT_HWCAP and /proc/cpuinfo.
58  static const InstructionSetFeatures* FromAssembly();
59
60  // Parse a string of the form "div,-atomic_ldrd_strd" adding and removing these features to
61  // create a new InstructionSetFeatures.
62  const InstructionSetFeatures* AddFeaturesFromString(const std::string& feature_list,
63                                                      std::string* error_msg) const WARN_UNUSED;
64
65  // Are these features the same as the other given features?
66  virtual bool Equals(const InstructionSetFeatures* other) const = 0;
67
68  // Return the ISA these features relate to.
69  virtual InstructionSet GetInstructionSet() const = 0;
70
71  // Return a bitmap that represents the features. ISA specific.
72  virtual uint32_t AsBitmap() const = 0;
73
74  // Return a string of the form "div,lpae" or "none".
75  virtual std::string GetFeatureString() const = 0;
76
77  // Does the instruction set variant require instructions for correctness with SMP?
78  bool IsSmp() const {
79    return smp_;
80  }
81
82  // Down cast this ArmInstructionFeatures.
83  const ArmInstructionSetFeatures* AsArmInstructionSetFeatures() const;
84
85  // Down cast this Arm64InstructionFeatures.
86  const Arm64InstructionSetFeatures* AsArm64InstructionSetFeatures() const;
87
88  // Down cast this MipsInstructionFeatures.
89  const MipsInstructionSetFeatures* AsMipsInstructionSetFeatures() const;
90
91  // Down cast this Mips64InstructionFeatures.
92  const Mips64InstructionSetFeatures* AsMips64InstructionSetFeatures() const;
93
94  // Down cast this X86InstructionFeatures.
95  const X86InstructionSetFeatures* AsX86InstructionSetFeatures() const;
96
97  // Down cast this X86_64InstructionFeatures.
98  const X86_64InstructionSetFeatures* AsX86_64InstructionSetFeatures() const;
99
100  virtual ~InstructionSetFeatures() {}
101
102 protected:
103  explicit InstructionSetFeatures(bool smp) : smp_(smp) {}
104
105  // Returns true if variant appears in the array variants.
106  static bool FindVariantInArray(const char* const variants[], size_t num_variants,
107                                 const std::string& variant);
108
109  // Add architecture specific features in sub-classes.
110  virtual const InstructionSetFeatures*
111      AddFeaturesFromSplitString(bool smp, const std::vector<std::string>& features,
112                                 std::string* error_msg) const = 0;
113
114 private:
115  const bool smp_;
116
117  DISALLOW_COPY_AND_ASSIGN(InstructionSetFeatures);
118};
119std::ostream& operator<<(std::ostream& os, const InstructionSetFeatures& rhs);
120
121}  // namespace art
122
123#endif  // ART_RUNTIME_ARCH_INSTRUCTION_SET_FEATURES_H_
124