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