------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S Y S T E M . D W A R F _ L I N E S -- -- -- -- S p e c -- -- -- -- Copyright (C) 2009-2017, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package provides routines to read DWARF line number information from -- a generic object file with as little overhead as possible. This allows -- conversions from PC addresses to human readable source locations. -- -- Objects must be built with debugging information, however only the -- .debug_line section of the object file is referenced. In cases where object -- size is a consideration it's possible to strip all other .debug sections, -- which will decrease the size of the object significantly. pragma Polling (Off); -- We must turn polling off for this unit, because otherwise we can get -- elaboration circularities when polling is turned on with Ada.Exceptions.Traceback; with System.Object_Reader; with System.Storage_Elements; with System.Bounded_Strings; package System.Dwarf_Lines is package AET renames Ada.Exceptions.Traceback; package SOR renames System.Object_Reader; type Dwarf_Context (In_Exception : Boolean := False) is private; -- Type encapsulation the state of the Dwarf reader. When In_Exception -- is True we are parsing as part of a exception handler decorator, we do -- not want an exception to be raised, the parsing is done safely skipping -- DWARF file that cannot be read or with stripped debug section for -- example. procedure Open (File_Name : String; C : out Dwarf_Context; Success : out Boolean); procedure Close (C : in out Dwarf_Context); -- Open and close files procedure Set_Load_Address (C : in out Dwarf_Context; Addr : Address); -- Set the load address of a file. This is used to rebase PIE (Position -- Independant Executable) binaries. function Is_Inside (C : Dwarf_Context; Addr : Address) return Boolean; pragma Inline (Is_Inside); -- Return true iff Addr is within the module function Low (C : Dwarf_Context) return Address; pragma Inline (Low); -- Return the lowest address of C procedure Dump (C : in out Dwarf_Context); -- Dump each row found in the object's .debug_lines section to standard out procedure Dump_Cache (C : Dwarf_Context); -- Dump the cache (if present) procedure Enable_Cache (C : in out Dwarf_Context); -- Read symbols information to speed up Symbolic_Traceback. procedure Symbolic_Traceback (Cin : Dwarf_Context; Traceback : AET.Tracebacks_Array; Suppress_Hex : Boolean; Symbol_Found : in out Boolean; Res : in out System.Bounded_Strings.Bounded_String); -- Generate a string for a traceback suitable for displaying to the user. -- If one or more symbols are found, Symbol_Found is set to True. This -- allows the caller to fall back to hexadecimal addresses. Dwarf_Error : exception; -- Raised if a problem is encountered parsing DWARF information. Can be a -- result of a logic error or malformed DWARF information. private -- The following section numbers reference -- "DWARF Debugging Information Format, Version 3" -- published by the Standards Group, http://freestandards.org. -- 6.2.2 State Machine Registers type Line_Info_Registers is record Address : SOR.uint64; File : SOR.uint32; Line : SOR.uint32; Column : SOR.uint32; Is_Stmt : Boolean; Basic_Block : Boolean; End_Sequence : Boolean; Prologue_End : Boolean; Epilogue_Begin : Boolean; ISA : SOR.uint32; Is_Row : Boolean; end record; -- 6.2.4 The Line Number Program Prologue MAX_OPCODE_LENGTHS : constant := 256; type Opcodes_Lengths_Array is array (SOR.uint32 range 1 .. MAX_OPCODE_LENGTHS) of SOR.uint8; type Line_Info_Prologue is record Unit_Length : SOR.uint32; Version : SOR.uint16; Prologue_Length : SOR.uint32; Min_Isn_Length : SOR.uint8; Default_Is_Stmt : SOR.uint8; Line_Base : SOR.int8; Line_Range : SOR.uint8; Opcode_Base : SOR.uint8; Opcode_Lengths : Opcodes_Lengths_Array; Includes_Offset : SOR.Offset; File_Names_Offset : SOR.Offset; end record; type Search_Entry is record First : SOR.uint32; Size : SOR.uint32; -- Function bounds as offset to the base address. Sym : SOR.uint32; -- Symbol offset to get the name. Line : SOR.uint32; -- Dwarf line offset. end record; type Search_Array is array (Natural range <>) of Search_Entry; type Search_Array_Access is access Search_Array; type Dwarf_Context (In_Exception : Boolean := False) is record Load_Slide : System.Storage_Elements.Integer_Address := 0; Low, High : Address; -- Bounds of the module Obj : SOR.Object_File_Access; -- The object file containing dwarf sections Has_Debug : Boolean; -- True if all debug sections are available Cache : Search_Array_Access; -- Quick access to symbol and debug info (when present). Lines : SOR.Mapped_Stream; Aranges : SOR.Mapped_Stream; Info : SOR.Mapped_Stream; Abbrev : SOR.Mapped_Stream; -- Dwarf line, aranges, info and abbrev sections Prologue : Line_Info_Prologue; Registers : Line_Info_Registers; Next_Prologue : SOR.Offset; -- State for lines end record; end System.Dwarf_Lines;