dfg/DFGDoubleFormatState.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 DFGDoubleFormatState_h
  27 #define DFGDoubleFormatState_h
  28
  29 namespace JSC { namespace DFG {
  30
  31 enum DoubleFormatState {
  32     EmptyDoubleFormatState, // bottom
  33     UsingDoubleFormat,
  34     NotUsingDoubleFormat,
  35     CantUseDoubleFormat // top
  36 };
  37
  38 inline DoubleFormatState mergeDoubleFormatStates(DoubleFormatState a, DoubleFormatState b)
  39 {
  40     switch (a) {
  41     case EmptyDoubleFormatState:
  42         return b;
  43     case UsingDoubleFormat:
  44         switch (b) {
  45         case EmptyDoubleFormatState:
  46         case UsingDoubleFormat:
  47             return UsingDoubleFormat;
  48         case NotUsingDoubleFormat:
  49         case CantUseDoubleFormat:
  50             return CantUseDoubleFormat;
  51         }
  52     case NotUsingDoubleFormat:
  53         switch (b) {
  54         case EmptyDoubleFormatState:
  55         case NotUsingDoubleFormat:
  56             return NotUsingDoubleFormat;
  57         case UsingDoubleFormat:
  58         case CantUseDoubleFormat:
  59             return CantUseDoubleFormat;
  60         }
  61     case CantUseDoubleFormat:
  62         return CantUseDoubleFormat;
  63     }
  64     RELEASE_ASSERT_NOT_REACHED();
  65     return CantUseDoubleFormat;
  66 }
  67
  68 inline bool mergeDoubleFormatState(DoubleFormatState& dest, DoubleFormatState src)
  69 {
  70     DoubleFormatState newState = mergeDoubleFormatStates(dest, src);
  71     if (newState == dest)
  72         return false;
  73     dest = newState;
  74     return true;
  75 }
  76
  77 inline const char* doubleFormatStateToString(DoubleFormatState state)
  78 {
  79     switch (state) {
  80     case EmptyDoubleFormatState:
  81         return "Empty";
  82     case UsingDoubleFormat:
  83         return "DoubleFormat";
  84     case NotUsingDoubleFormat:
  85         return "ValueFormat";
  86     case CantUseDoubleFormat:
  87         return "ForceValue";
  88     }
  89     RELEASE_ASSERT_NOT_REACHED();
  90     return 0;
  91 }
  92
  93 } } // namespace JSC::DFG
  94
  95 #endif // DFGDoubleFormatState_h
  96