Home | History | Annotate | Download | only in mips 
      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 
     24 namespace art {
     25 
     26 class MipsInstructionSetFeatures;
     27 using MipsFeaturesUniquePtr = std::unique_ptr<const MipsInstructionSetFeatures>;
     28 
     29 // Instruction set features relevant to the MIPS architecture.
     30 class MipsInstructionSetFeatures FINAL : public InstructionSetFeatures {
     31  public:
     32   // Process a CPU variant string like "r4000" and create InstructionSetFeatures.
     33   static MipsFeaturesUniquePtr FromVariant(const std::string& variant, std::string* error_msg);
     34 
     35   // Parse a bitmap and create an InstructionSetFeatures.
     36   static MipsFeaturesUniquePtr FromBitmap(uint32_t bitmap);
     37 
     38   // Turn C pre-processor #defines into the equivalent instruction set features.
     39   static MipsFeaturesUniquePtr FromCppDefines();
     40 
     41   // Process /proc/cpuinfo and use kRuntimeISA to produce InstructionSetFeatures.
     42   static MipsFeaturesUniquePtr FromCpuInfo();
     43 
     44   // Process the auxiliary vector AT_HWCAP entry and use kRuntimeISA to produce
     45   // InstructionSetFeatures.
     46   static MipsFeaturesUniquePtr FromHwcap();
     47 
     48   // Use assembly tests of the current runtime (ie kRuntimeISA) to determine the
     49   // InstructionSetFeatures. This works around kernel bugs in AT_HWCAP and /proc/cpuinfo.
     50   static MipsFeaturesUniquePtr FromAssembly();
     51 
     52   bool Equals(const InstructionSetFeatures* other) const OVERRIDE;
     53 
     54   InstructionSet GetInstructionSet() const OVERRIDE {
     55     return kMips;
     56   }
     57 
     58   uint32_t AsBitmap() const OVERRIDE;
     59 
     60   std::string GetFeatureString() const OVERRIDE;
     61 
     62   // Is this an ISA revision greater than 2 opening up new opcodes.
     63   bool IsMipsIsaRevGreaterThanEqual2() const {
     64     return mips_isa_gte2_;
     65   }
     66 
     67   // Floating point double registers are encoded differently based on whether the Status.FR bit is
     68   // set. When the FR bit is 0 then the FPU is 32-bit, 1 its 64-bit. Return true if the code should
     69   // be generated assuming Status.FR is 0.
     70   bool Is32BitFloatingPoint() const {
     71     return fpu_32bit_;
     72   }
     73 
     74   bool IsR6() const {
     75     return r6_;
     76   }
     77 
     78   virtual ~MipsInstructionSetFeatures() {}
     79 
     80  protected:
     81   // Parse a vector of the form "fpu32", "mips2" adding these to a new MipsInstructionSetFeatures.
     82   std::unique_ptr<const InstructionSetFeatures>
     83       AddFeaturesFromSplitString(const std::vector<std::string>& features,
     84                                  std::string* error_msg) const OVERRIDE;
     85 
     86  private:
     87   MipsInstructionSetFeatures(bool fpu_32bit, bool mips_isa_gte2, bool r6)
     88       : InstructionSetFeatures(),
     89         fpu_32bit_(fpu_32bit),
     90         mips_isa_gte2_(mips_isa_gte2),
     91         r6_(r6) {
     92     // Sanity checks.
     93     if (r6) {
     94       CHECK(mips_isa_gte2);
     95       CHECK(!fpu_32bit);
     96     }
     97     if (!mips_isa_gte2) {
     98       CHECK(fpu_32bit);
     99     }
    100   }
    101 
    102   // Bitmap positions for encoding features as a bitmap.
    103   enum {
    104     kFpu32Bitfield = 1 << 0,
    105     kIsaRevGte2Bitfield = 1 << 1,
    106     kR6 = 1 << 2,
    107   };
    108 
    109   const bool fpu_32bit_;
    110   const bool mips_isa_gte2_;
    111   const bool r6_;
    112 
    113   DISALLOW_COPY_AND_ASSIGN(MipsInstructionSetFeatures);
    114 };
    115 
    116 }  // namespace art
    117 
    118 #endif  // ART_RUNTIME_ARCH_MIPS_INSTRUCTION_SET_FEATURES_MIPS_H_
    119