dfg/DFGRegisterSet.h

   1 /*
   2  * Copyright (C) 2012 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 DFGRegisterSet_h
  27 #define DFGRegisterSet_h
  28
  29 #include <wtf/Platform.h>
  30
  31 #if ENABLE(DFG_JIT)
  32
  33 #include "DFGFPRInfo.h"
  34 #include "DFGGPRInfo.h"
  35 #include <wtf/Bitmap.h>
  36
  37 namespace JSC { namespace DFG {
  38
  39 static const unsigned totalNumberOfRegisters =
  40     GPRInfo::numberOfRegisters + FPRInfo::numberOfRegisters;
  41
  42 static const unsigned numberOfBytesInRegisterSet =
  43     (totalNumberOfRegisters + 7) >> 3;
  44
  45 typedef uint8_t RegisterSetPOD[numberOfBytesInRegisterSet];
  46
  47 class RegisterSet {
  48 public:
  49     RegisterSet()
  50     {
  51         for (unsigned i = numberOfBytesInRegisterSet; i--;)
  52             m_set[i] = 0;
  53     }
  54
  55     RegisterSet(const RegisterSetPOD& other)
  56     {
  57         for (unsigned i = numberOfBytesInRegisterSet; i--;)
  58             m_set[i] = other[i];
  59     }
  60
  61     const RegisterSetPOD& asPOD() const { return m_set; }
  62
  63     void copyInfo(RegisterSetPOD& other) const
  64     {
  65         for (unsigned i = numberOfBytesInRegisterSet; i--;)
  66             other[i] = m_set[i];
  67     }
  68
  69     void set(GPRReg reg)
  70     {
  71         setBit(GPRInfo::toIndex(reg));
  72     }
  73
  74     void setGPRByIndex(unsigned index)
  75     {
  76         ASSERT(index < GPRInfo::numberOfRegisters);
  77         setBit(index);
  78     }
  79
  80     void clear(GPRReg reg)
  81     {
  82         clearBit(GPRInfo::toIndex(reg));
  83     }
  84
  85     bool get(GPRReg reg) const
  86     {
  87         return getBit(GPRInfo::toIndex(reg));
  88     }
  89
  90     bool getGPRByIndex(unsigned index) const
  91     {
  92         ASSERT(index < GPRInfo::numberOfRegisters);
  93         return getBit(index);
  94     }
  95
  96     // Return the index'th free GPR.
  97     GPRReg getFreeGPR(unsigned index = 0) const
  98     {
  99         for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
 100             if (!getGPRByIndex(i) && !index--)
 101                 return GPRInfo::toRegister(i);
 102         }
 103         return InvalidGPRReg;
 104     }
 105
 106     void set(FPRReg reg)
 107     {
 108         setBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
 109     }
 110
 111     void setFPRByIndex(unsigned index)
 112     {
 113         ASSERT(index < FPRInfo::numberOfRegisters);
 114         setBit(GPRInfo::numberOfRegisters + index);
 115     }
 116
 117     void clear(FPRReg reg)
 118     {
 119         clearBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
 120     }
 121
 122     bool get(FPRReg reg) const
 123     {
 124         return getBit(GPRInfo::numberOfRegisters + FPRInfo::toIndex(reg));
 125     }
 126
 127     bool getFPRByIndex(unsigned index) const
 128     {
 129         ASSERT(index < FPRInfo::numberOfRegisters);
 130         return getBit(GPRInfo::numberOfRegisters + index);
 131     }
 132
 133     template<typename BankInfo>
 134     void setByIndex(unsigned index)
 135     {
 136         set(BankInfo::toRegister(index));
 137     }
 138
 139     template<typename BankInfo>
 140     bool getByIndex(unsigned index)
 141     {
 142         return get(BankInfo::toRegister(index));
 143     }
 144
 145     unsigned numberOfSetGPRs() const
 146     {
 147         unsigned result = 0;
 148         for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
 149             if (!getBit(i))
 150                 continue;
 151             result++;
 152         }
 153         return result;
 154     }
 155
 156     unsigned numberOfSetFPRs() const
 157     {
 158         unsigned result = 0;
 159         for (unsigned i = FPRInfo::numberOfRegisters; i--;) {
 160             if (!getBit(GPRInfo::numberOfRegisters + i))
 161                 continue;
 162             result++;
 163         }
 164         return result;
 165     }
 166
 167     unsigned numberOfSetRegisters() const
 168     {
 169         unsigned result = 0;
 170         for (unsigned i = totalNumberOfRegisters; i--;) {
 171             if (!getBit(i))
 172                 continue;
 173             result++;
 174         }
 175         return result;
 176     }
 177
 178 private:
 179     void setBit(unsigned i)
 180     {
 181         ASSERT(i < totalNumberOfRegisters);
 182         m_set[i >> 3] |= (1 << (i & 7));
 183     }
 184
 185     void clearBit(unsigned i)
 186     {
 187         ASSERT(i < totalNumberOfRegisters);
 188         m_set[i >> 3] &= ~(1 << (i & 7));
 189     }
 190
 191     bool getBit(unsigned i) const
 192     {
 193         ASSERT(i < totalNumberOfRegisters);
 194         return !!(m_set[i >> 3] & (1 << (i & 7)));
 195     }
 196
 197     RegisterSetPOD m_set;
 198 };
 199
 200 } } // namespace JSC::DFG
 201
 202 #else // ENABLE(DFG_JIT) -> so if DFG is disabled
 203
 204 namespace JSC { namespace DFG {
 205
 206 // Define RegisterSetPOD to something that is a POD, but is otherwise useless,
 207 // to make it easier to refer to this type in code that may be compiled when
 208 // the DFG is disabled.
 209
 210 struct RegisterSetPOD { };
 211
 212 } } // namespace JSC::DFG
 213
 214 #endif // ENABLE(DFG_JIT)
 215
 216 #endif // DFGRegisterSet_h
 217