jit/TempRegisterSet.h

   1 /*
   2  * Copyright (C) 2012, 2013 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef TempRegisterSet_h
  27 #define TempRegisterSet_h
  28
  29 #if ENABLE(JIT)
  30
  31 #include "FPRInfo.h"
  32 #include "GPRInfo.h"
  33
  34 namespace JSC {
  35
  36 class RegisterSet;
  37
  38 class TempRegisterSet {
  39 public:
  40     TempRegisterSet()
  41     {
  42         clearAll();
  43     }
  44
  45     TempRegisterSet(const RegisterSet&);
  46
  47     void set(GPRReg reg)
  48     {
  49         setBit(GPRInfo::toIndex(reg));
  50     }
  51
  52     void set(JSValueRegs regs)
  53     {
  54         if (regs.tagGPR() != InvalidGPRReg)
  55             set(regs.tagGPR());
  56         set(regs.payloadGPR());
  57     }
  58
  59     void setGPRByIndex(unsigned index)
  60     {
  61         ASSERT(index < GPRInfo::numberOfRegisters);
  62         setBit(index);
  63     }
  64
  65     void clear(GPRReg reg)
  66     {
  67         clearBit(GPRInfo::toIndex(reg));
  68     }
  69
  70     bool get(GPRReg reg) const
  71     {
  72         return getBit(GPRInfo::toIndex(reg));
  73     }
  74
  75     bool getGPRByIndex(unsigned index) const
  76     {
  77         ASSERT(index < GPRInfo::numberOfRegisters);
  78         return getBit(index);
  79     }
  80
  81     // Return the index'th free GPR.
  82     GPRReg getFreeGPR(unsigned index = 0) const
  83     {
  84         for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
  85             if (!getGPRByIndex(i) && !index--)
  86                 return GPRInfo::toRegister(i);
  87         }
  88         return InvalidGPRReg;
  89     }
  90
  91     void set(FPRReg reg)
  92     {
  93         setBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
  94     }
  95
  96     void setFPRByIndex(unsigned index)
  97     {
  98         ASSERT(index < FPRInfo::numberOfRegisters);
  99         setBit(GPRInfo::numberOfRegisters + index);
 100     }
 101
 102     void clear(FPRReg reg)
 103     {
 104         clearBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
 105     }
 106
 107     bool get(FPRReg reg) const
 108     {
 109         return getBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
 110     }
 111
 112     bool getFPRByIndex(unsigned index) const
 113     {
 114         ASSERT(index < FPRInfo::numberOfRegisters);
 115         return getBit(GPRInfo::numberOfRegisters + index);
 116     }
 117
 118     template<typename BankInfo>
 119     void setByIndex(unsigned index)
 120     {
 121         set(BankInfo::toRegister(index));
 122     }
 123
 124     template<typename BankInfo>
 125     bool getByIndex(unsigned index)
 126     {
 127         return get(BankInfo::toRegister(index));
 128     }
 129
 130     unsigned numberOfSetGPRs() const
 131     {
 132         unsigned result = 0;
 133         for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
 134             if (!getBit(i))
 135                 continue;
 136             result++;
 137         }
 138         return result;
 139     }
 140
 141     unsigned numberOfSetFPRs() const
 142     {
 143         unsigned result = 0;
 144         for (unsigned i = FPRInfo::numberOfRegisters; i--;) {
 145             if (!getBit(GPRInfo::numberOfRegisters + i))
 146                 continue;
 147             result++;
 148         }
 149         return result;
 150     }
 151
 152     unsigned numberOfSetRegisters() const
 153     {
 154         unsigned result = 0;
 155         for (unsigned i = totalNumberOfRegisters; i--;) {
 156             if (!getBit(i))
 157                 continue;
 158             result++;
 159         }
 160         return result;
 161     }
 162
 163 private:
 164     void clearAll()
 165     {
 166         for (unsigned i = numberOfBytesInTempRegisterSet; i--;)
 167             m_set[i] = 0;
 168     }
 169
 170     void setBit(unsigned i)
 171     {
 172         ASSERT(i < totalNumberOfRegisters);
 173         m_set[i >> 3] |= (1 << (i & 7));
 174     }
 175
 176     void clearBit(unsigned i)
 177     {
 178         ASSERT(i < totalNumberOfRegisters);
 179         m_set[i >> 3] &= ~(1 << (i & 7));
 180     }
 181
 182     bool getBit(unsigned i) const
 183     {
 184         ASSERT(i < totalNumberOfRegisters);
 185         return !!(m_set[i >> 3] & (1 << (i & 7)));
 186     }
 187
 188     static const unsigned totalNumberOfRegisters =
 189         GPRInfo::numberOfRegisters + FPRInfo::numberOfRegisters;
 190
 191     static const unsigned numberOfBytesInTempRegisterSet =
 192         (totalNumberOfRegisters + 7) >> 3;
 193
 194     uint8_t m_set[numberOfBytesInTempRegisterSet];
 195 };
 196
 197 } // namespace JSC
 198
 199 #else // ENABLE(JIT) -> so if JIT is disabled
 200
 201 namespace JSC {
 202
 203 // Define TempRegisterSet to something, to make it easier to refer to this type in code that
 204 // make be compiled when the JIT is disabled.
 205
 206 struct TempRegisterSet { };
 207
 208 } // namespace JSC
 209
 210 #endif // ENABLE(JIT)
 211
 212 #endif // TempRegisterSet_h
 213