Amiga ACS 1998 #4/amigaacscoverdisc1998-041998.iso/utilities/shareware/dev/ppcsmalleiffel/lib_se/instruction.e

Text File | 1998-01-16 | 4.7 KB | 206 lines

--          This file is part of SmallEiffel The GNU Eiffel Compiler.
--          Copyright (C) 1994-98 LORIA - UHP - CRIN - INRIA - FRANCE
--            Dominique COLNET and Suzanne COLLIN - [e-mail]
--                       http://www.loria.fr/SmallEiffel
-- SmallEiffel is  free  software;  you can  redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the Free
-- Software  Foundation;  either  version  2, or (at your option)  any  later
-- version. SmallEiffel is distributed in the hope that it will be useful,but
-- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-- or  FITNESS FOR A PARTICULAR PURPOSE.   See the GNU General Public License
-- for  more  details.  You  should  have  received a copy of the GNU General
-- Public  License  along  with  SmallEiffel;  see the file COPYING.  If not,
-- write to the  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-- Boston, MA 02111-1307, USA.
--
deferred class INSTRUCTION
--
-- For all differents kinds of Eiffel instruction.
--

inherit
   GLOBALS
      redefine fill_tagged_out_memory
      end;


feature

   fill_tagged_out_memory is
      local
     p: POSITION;
     ct: TYPE;
     rtm: STRING;
      do
     p := start_position;
     if p /= Void then
        p.fill_tagged_out_memory;
     end;
     if run_compound /= Void then
        ct := run_compound.current_type;
        if ct /= Void then
           rtm := ct.run_time_mark;
           if rtm /= Void then
          tagged_out_memory.append(" ct=");
          tagged_out_memory.append(rtm);
           end;
        end;
     end;
      end;

   run_compound: COMPOUND;
     -- When not Void, the instruction is checked and belongs to
     -- this compound

   start_position: POSITION is
     -- Of the first character of the instruction.
      deferred
      ensure
     Result /= Void
      end;

   pretty_print is
      require
     fmt.indent_level >= 3;
      deferred
      ensure
     fmt.indent_level = old fmt.indent_level;
      end;

   use_current: BOOLEAN is
      -- Does instruction use Current ?
      require
     is_checked;
     small_eiffel.is_ready;
      deferred
      end;

   to_runnable(rc: like run_compound): like Current is
      -- Gives a checked instruction runnable in `rc.current_type'.
      require
     rc /= Void;
     rc.current_type /= Void;
     rc.current_type.is_run_type
      deferred
      ensure
     nb_errors = 0 implies Result /= Void;
     Result /= Void implies Result.run_compound = rc;
      end;

   is_checked: BOOLEAN is
     -- Instruction is checked ?
      do
     Result := run_compound /= Void;
      end;

   run_class: RUN_CLASS is
      require
     is_checked
      do
     Result := run_compound.run_class;
      ensure
     Result /= Void;
      end;

   current_type: TYPE is
      require
     is_checked
      do
     if run_compound /= Void then
        Result := run_compound.current_type;
     end;
      ensure
     Result /= Void;
      end;

   end_mark_comment: BOOLEAN is
     -- True for instructions with a possible end mark comment
     -- like instruction "loop" "debug" or "check" for example.
      deferred
      end;

   afd_check is
     -- After Falling Down Check.
      require
     is_checked;
      deferred
      end;

   compile_to_c is
      require
     is_checked;
     cpp.on_c
      deferred
      ensure
     cpp.on_c
      end;

   compile_to_jvm is
      require
     is_checked
      deferred
      ensure
      end;

   is_pre_computable: BOOLEAN is
     -- Assume the current instruction is inside a once function.
     -- Result is true when the instruction can be precomputed.
      require
     is_checked;
     small_eiffel.is_ready
      deferred
      end;

feature {EIFFEL_PARSER}

   add_comment(c: COMMENT): INSTRUCTION is
     -- Attach `c' to the instruction.
      require
     eiffel_parser.is_running
      do
     if c = Void or else c.count = 0 then
        Result := Current
     elseif end_mark_comment then
        if c.count = 1 then
           Result := Current;
        else
           !INSTRUCTION_WITH_COMMENT!Result.make(Current,c);
        end;
     else
        !INSTRUCTION_WITH_COMMENT!Result.make(Current,c);
     end;
      end;

feature {INSTRUCTION}

   set_run_compound(rc: like run_compound) is
      do
     run_compound := rc;
      ensure
     run_compound = rc;
      end;

feature {NONE}

   pretty_print_assignment(rhs: EXPRESSION; op: STRING; lhs: EXPRESSION) is
      local
     semi_colon_flag: BOOLEAN;
      do
     rhs.pretty_print;
     fmt.put_character(' ');
     fmt.put_string(op);
     fmt.put_character(' ');
     semi_colon_flag := fmt.semi_colon_flag;
     fmt.level_incr;
     fmt.set_semi_colon_flag(false);
     lhs.pretty_print;
     fmt.set_semi_colon_flag(semi_colon_flag);
     if semi_colon_flag then
        fmt.put_character(';');
     end;
     fmt.level_decr;
      end;

end -- INSTRUCTION