1 /*
   2  * Copyright (c) 2002, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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  23  */
  24 
  25 #ifndef SHARE_VM_RUNTIME_REGISTERMAP_HPP
  26 #define SHARE_VM_RUNTIME_REGISTERMAP_HPP
  27 
  28 #include "code/vmreg.hpp"
  29 #include "utilities/globalDefinitions.hpp"
  30 #ifdef TARGET_ARCH_x86
  31 # include "register_x86.hpp"
  32 #endif
  33 #ifdef TARGET_ARCH_sparc
  34 # include "register_sparc.hpp"
  35 #endif
  36 #ifdef TARGET_ARCH_zero
  37 # include "register_zero.hpp"
  38 #endif
  39 #ifdef TARGET_ARCH_arm
  40 # include "register_arm.hpp"
  41 #endif
  42 #ifdef TARGET_ARCH_ppc
  43 # include "register_ppc.hpp"
  44 #endif
  45 #ifdef TARGET_ARCH_aarch32
  46 # include "register_aarch32.hpp"
  47 #endif
  48 
  49 class JavaThread;
  50 
  51 //
  52 // RegisterMap
  53 //
  54 // A companion structure used for stack traversal. The RegisterMap contains
  55 // misc. information needed in order to do correct stack traversal of stack
  56 // frames.  Hence, it must always be passed in as an argument to
  57 // frame::sender(RegisterMap*).
  58 //
  59 // In particular,
  60 //   1) It provides access to the thread for which the stack belongs.  The
  61 //      thread object is needed in order to get sender of a deoptimized frame.
  62 //
  63 //   2) It is used to pass information from a callee frame to its caller
  64 //      frame about how the frame should be traversed.  This is used to let
  65 //      the caller frame take care of calling oops-do of out-going
  66 //      arguments, when the callee frame is not instantiated yet.  This
  67 //      happens, e.g., when a compiled frame calls into
  68 //      resolve_virtual_call.  (Hence, it is critical that the same
  69 //      RegisterMap object is used for the entire stack walk.  Normally,
  70 //      this is hidden by using the StackFrameStream.)  This is used when
  71 //      doing follow_oops and oops_do.
  72 //
  73 //   3) The RegisterMap keeps track of the values of callee-saved registers
  74 //      from frame to frame (hence, the name).  For some stack traversal the
  75 //      values of the callee-saved registers does not matter, e.g., if you
  76 //      only need the static properies such as frame type, pc, and such.
  77 //      Updating of the RegisterMap can be turned off by instantiating the
  78 //      register map as: RegisterMap map(thread, false);
  79 
  80 class RegisterMap : public StackObj {
  81  public:
  82     typedef julong LocationValidType;
  83   enum {
  84     reg_count = ConcreteRegisterImpl::number_of_registers,
  85     location_valid_type_size = sizeof(LocationValidType)*8,
  86     location_valid_size = (reg_count+location_valid_type_size-1)/location_valid_type_size
  87   };
  88  private:
  89   intptr_t*    _location[reg_count];    // Location of registers (intptr_t* looks better than address in the debugger)
  90   LocationValidType _location_valid[location_valid_size];
  91   bool        _include_argument_oops;   // Should include argument_oop marked locations for compiler
  92   JavaThread* _thread;                  // Reference to current thread
  93   bool        _update_map;              // Tells if the register map need to be
  94                                         // updated when traversing the stack
  95 
  96 #ifdef ASSERT
  97   void check_location_valid();
  98 #else
  99   void check_location_valid() {}
 100 #endif
 101 
 102  public:
 103   debug_only(intptr_t* _update_for_id;) // Assert that RegisterMap is not updated twice for same frame
 104   RegisterMap(JavaThread *thread, bool update_map = true);
 105   RegisterMap(const RegisterMap* map);
 106 
 107   address location(VMReg reg) const {
 108     int index = reg->value() / location_valid_type_size;
 109     assert(0 <= reg->value() && reg->value() < reg_count, "range check");
 110     assert(0 <= index && index < location_valid_size, "range check");
 111     if (_location_valid[index] & ((LocationValidType)1 << (reg->value() % location_valid_type_size))) {
 112       return (address) _location[reg->value()];
 113     } else {
 114       return pd_location(reg);
 115     }
 116   }
 117 
 118   void set_location(VMReg reg, address loc) {
 119     int index = reg->value() / location_valid_type_size;
 120     assert(0 <= reg->value() && reg->value() < reg_count, "range check");
 121     assert(0 <= index && index < location_valid_size, "range check");
 122     assert(_update_map, "updating map that does not need updating");
 123     _location[reg->value()] = (intptr_t*) loc;
 124     _location_valid[index] |= ((LocationValidType)1 << (reg->value() % location_valid_type_size));
 125     check_location_valid();
 126   }
 127 
 128   // Called by an entry frame.
 129   void clear();
 130 
 131   bool include_argument_oops() const      { return _include_argument_oops; }
 132   void set_include_argument_oops(bool f)  { _include_argument_oops = f; }
 133 
 134   JavaThread *thread() const { return _thread; }
 135   bool update_map()    const { return _update_map; }
 136 
 137   void print_on(outputStream* st) const;
 138   void print() const;
 139 
 140   // the following contains the definition of pd_xxx methods
 141 #ifdef TARGET_ARCH_x86
 142 # include "registerMap_x86.hpp"
 143 #endif
 144 #ifdef TARGET_ARCH_sparc
 145 # include "registerMap_sparc.hpp"
 146 #endif
 147 #ifdef TARGET_ARCH_zero
 148 # include "registerMap_zero.hpp"
 149 #endif
 150 #ifdef TARGET_ARCH_arm
 151 # include "registerMap_arm.hpp"
 152 #endif
 153 #ifdef TARGET_ARCH_ppc
 154 # include "registerMap_ppc.hpp"
 155 #endif
 156 #ifdef TARGET_ARCH_aarch32
 157 # include "registerMap_aarch32.hpp"
 158 #endif
 159 
 160 };
 161 
 162 #endif // SHARE_VM_RUNTIME_REGISTERMAP_HPP