File : s-traent.ads


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--                                                                          --
--                         GNAT RUN-TIME COMPONENTS                         --
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--  This package offers an abstraction of what is stored in traceback arrays
--  for call-chain computation purposes. By default, as defined in this
--  version of the package, an entry is a mere code location representing the
--  address of a call instruction part of the call-chain.

pragma Compiler_Unit;

package System.Traceback_Entries is
   pragma Preelaborate;

   subtype Traceback_Entry is System.Address;
   --  This subtype defines what each traceback array entry contains

   Null_TB_Entry : constant Traceback_Entry := System.Null_Address;
   --  This is the value to be used when initializing an entry

   function PC_For (TB_Entry : Traceback_Entry) return System.Address;
   pragma Inline (PC_For);
   --  Returns the address of the call instruction associated with the
   --  provided entry.

   function TB_Entry_For (PC : System.Address) return Traceback_Entry;
   pragma Inline (TB_Entry_For);
   --  Returns an entry representing a frame for a call instruction at PC

end System.Traceback_Entries;