1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  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
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 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
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 24 
 25 #ifndef SHARE_CODE_PCDESC_HPP
 26 #define SHARE_CODE_PCDESC_HPP
 27 
 28 
 29 // PcDescs map a physical PC (given as offset from start of nmethod) to
 30 // the corresponding source scope and byte code index.
 31 
 32 class CompiledMethod;
 33 
 34 class PcDesc {
 35   friend class VMStructs;
 36  private:
 37   int _pc_offset;           // offset from start of nmethod
 38   int _scope_decode_offset; // offset for scope in nmethod
 39   int _obj_decode_offset;
 40 
 41   enum {
 42     PCDESC_reexecute                 = 1 << 0,
 43     PCDESC_is_method_handle_invoke   = 1 << 1,
 44     PCDESC_return_oop                = 1 << 2,
 45     PCDESC_rethrow_exception         = 1 << 3,
 46     PCDESC_has_ea_local_in_scope     = 1 << 4,
 47     PCDESC_arg_escape                = 1 << 5,
 48     PCDESC_is_optimized_linkToNative = 1 << 6
 49   };
 50 
 51   int _flags;
 52 
 53   void set_flag(int mask, bool z) {
 54     _flags = z ? (_flags | mask) : (_flags & ~mask);
 55   }
 56 
 57  public:
 58   int pc_offset() const           { return _pc_offset;   }
 59   int scope_decode_offset() const { return _scope_decode_offset; }
 60   int obj_decode_offset() const   { return _obj_decode_offset; }
 61 
 62   void set_pc_offset(int x)           { _pc_offset           = x; }
 63   void set_scope_decode_offset(int x) { _scope_decode_offset = x; }
 64   void set_obj_decode_offset(int x)   { _obj_decode_offset   = x; }
 65 
 66   // Constructor (only used for static in nmethod.cpp)
 67   // Also used by ScopeDesc::sender()]
 68   PcDesc(int pc_offset, int scope_decode_offset, int obj_decode_offset);
 69 
 70   enum {
 71     // upper and lower exclusive limits real offsets:
 72     lower_offset_limit = -1,
 73     upper_offset_limit = (unsigned int)-1 >> 1
 74   };
 75 
 76   // Flags
 77   bool     rethrow_exception()              const { return (_flags & PCDESC_rethrow_exception) != 0; }
 78   void set_rethrow_exception(bool z)              { set_flag(PCDESC_rethrow_exception, z); }
 79   bool     should_reexecute()              const { return (_flags & PCDESC_reexecute) != 0; }
 80   void set_should_reexecute(bool z)              { set_flag(PCDESC_reexecute, z); }
 81 
 82   // Does pd refer to the same information as pd?
 83   bool is_same_info(const PcDesc* pd) {
 84     return _scope_decode_offset == pd->_scope_decode_offset &&
 85       _obj_decode_offset == pd->_obj_decode_offset &&
 86       _flags == pd->_flags;
 87   }
 88 
 89   bool     is_method_handle_invoke()       const { return (_flags & PCDESC_is_method_handle_invoke) != 0;     }
 90   void set_is_method_handle_invoke(bool z)       { set_flag(PCDESC_is_method_handle_invoke, z); }
 91 
 92   bool     is_optimized_linkToNative()     const { return (_flags & PCDESC_is_optimized_linkToNative) != 0;     }
 93   void set_is_optimized_linkToNative(bool z)     { set_flag(PCDESC_is_optimized_linkToNative, z); }
 94 
 95   bool     return_oop()                    const { return (_flags & PCDESC_return_oop) != 0;     }
 96   void set_return_oop(bool z)                    { set_flag(PCDESC_return_oop, z); }
 97 
 98   // Indicates if there are objects in scope that, based on escape analysis, are local to the
 99   // compiled method or local to the current thread, i.e. NoEscape or ArgEscape
100   bool     has_ea_local_in_scope()         const { return (_flags & PCDESC_has_ea_local_in_scope) != 0; }
101   void set_has_ea_local_in_scope(bool z)         { set_flag(PCDESC_has_ea_local_in_scope, z); }
102 
103   // Indicates if this pc descriptor is at a call site where objects that do not escape the
104   // current thread are passed as arguments.
105   bool     arg_escape()                    const { return (_flags & PCDESC_arg_escape) != 0; }
106   void set_arg_escape(bool z)                    { set_flag(PCDESC_arg_escape, z); }
107 
108   // Returns the real pc
109   address real_pc(const CompiledMethod* code) const;
110 
111   void print(CompiledMethod* code) { print_on(tty, code); }
112   void print_on(outputStream* st, CompiledMethod* code);
113   bool verify(CompiledMethod* code);
114 };
115 
116 #endif // SHARE_CODE_PCDESC_HPP