instruction_set_features_mips.h revision bda1d606f2d31086874b68edd9254e3817d8049c 
1/*
2 * Copyright (C) 2014 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_MIPS_INSTRUCTION_SET_FEATURES_MIPS_H_
18#define ART_RUNTIME_ARCH_MIPS_INSTRUCTION_SET_FEATURES_MIPS_H_
19
20#include "arch/instruction_set_features.h"
21#include "base/logging.h"
22#include "base/macros.h"
23
24namespace art {
25
26// Instruction set features relevant to the MIPS architecture.
27class MipsInstructionSetFeatures FINAL : public InstructionSetFeatures {
28 public:
29  // Process a CPU variant string like "r4000" and create InstructionSetFeatures.
30  static const MipsInstructionSetFeatures* FromVariant(const std::string& variant,
31                                                        std::string* error_msg);
32
33  // Parse a bitmap and create an InstructionSetFeatures.
34  static const MipsInstructionSetFeatures* FromBitmap(uint32_t bitmap);
35
36  // Turn C pre-processor #defines into the equivalent instruction set features.
37  static const MipsInstructionSetFeatures* FromCppDefines();
38
39  // Process /proc/cpuinfo and use kRuntimeISA to produce InstructionSetFeatures.
40  static const MipsInstructionSetFeatures* FromCpuInfo();
41
42  // Process the auxiliary vector AT_HWCAP entry and use kRuntimeISA to produce
43  // InstructionSetFeatures.
44  static const MipsInstructionSetFeatures* FromHwcap();
45
46  // Use assembly tests of the current runtime (ie kRuntimeISA) to determine the
47  // InstructionSetFeatures. This works around kernel bugs in AT_HWCAP and /proc/cpuinfo.
48  static const MipsInstructionSetFeatures* FromAssembly();
49
50  bool Equals(const InstructionSetFeatures* other) const OVERRIDE;
51
52  InstructionSet GetInstructionSet() const OVERRIDE {
53    return kMips;
54  }
55
56  uint32_t AsBitmap() const OVERRIDE;
57
58  std::string GetFeatureString() const OVERRIDE;
59
60  // Is this an ISA revision greater than 2 opening up new opcodes.
61  bool IsMipsIsaRevGreaterThanEqual2() const {
62    return mips_isa_gte2_;
63  }
64
65  // Floating point double registers are encoded differently based on whether the Status.FR bit is
66  // set. When the FR bit is 0 then the FPU is 32-bit, 1 its 64-bit. Return true if the code should
67  // be generated assuming Status.FR is 0.
68  bool Is32BitFloatingPoint() const {
69    return fpu_32bit_;
70  }
71
72  bool IsR6() const {
73    return r6_;
74  }
75
76  virtual ~MipsInstructionSetFeatures() {}
77
78 protected:
79  // Parse a vector of the form "fpu32", "mips2" adding these to a new MipsInstructionSetFeatures.
80  virtual const InstructionSetFeatures*
81      AddFeaturesFromSplitString(const bool smp, const std::vector<std::string>& features,
82                                 std::string* error_msg) const OVERRIDE;
83
84 private:
85  MipsInstructionSetFeatures(bool smp, bool fpu_32bit, bool mips_isa_gte2, bool r6)
86      : InstructionSetFeatures(smp),
87        fpu_32bit_(fpu_32bit),
88        mips_isa_gte2_(mips_isa_gte2),
89        r6_(r6) {
90    // Sanity checks.
91    if (r6) {
92      CHECK(mips_isa_gte2);
93      CHECK(!fpu_32bit);
94    }
95    if (!mips_isa_gte2) {
96      CHECK(fpu_32bit);
97    }
98  }
99
100  // Bitmap positions for encoding features as a bitmap.
101  enum {
102    kSmpBitfield = 1,
103    kFpu32Bitfield = 2,
104    kIsaRevGte2Bitfield = 4,
105    kR6 = 8,
106  };
107
108  const bool fpu_32bit_;
109  const bool mips_isa_gte2_;
110  const bool r6_;
111
112  DISALLOW_COPY_AND_ASSIGN(MipsInstructionSetFeatures);
113};
114
115}  // namespace art
116
117#endif  // ART_RUNTIME_ARCH_MIPS_INSTRUCTION_SET_FEATURES_MIPS_H_
118