old-autovect-branch/gcc/ada/frontend.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             F R O N T E N D                              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2005, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 with GNAT.Strings; use GNAT.Strings;
  28
  29 with Atree;    use Atree;
  30 with Checks;
  31 with CStand;
  32 with Debug;    use Debug;
  33 with Elists;
  34 with Exp_Dbug;
  35 with Fmap;
  36 with Fname.UF;
  37 with Hostparm; use Hostparm;
  38 with Inline;   use Inline;
  39 with Lib;      use Lib;
  40 with Lib.Load; use Lib.Load;
  41 with Live;     use Live;
  42 with Namet;    use Namet;
  43 with Nlists;   use Nlists;
  44 with Opt;      use Opt;
  45 with Osint;
  46 with Output;   use Output;
  47 with Par;
  48 with Prepcomp;
  49 with Rtsfind;
  50 with Sprint;
  51 with Scn;      use Scn;
  52 with Sem;      use Sem;
  53 with Sem_Ch8;  use Sem_Ch8;
  54 with Sem_Elab; use Sem_Elab;
  55 with Sem_Prag; use Sem_Prag;
  56 with Sem_Warn; use Sem_Warn;
  57 with Sinfo;    use Sinfo;
  58 with Sinput;   use Sinput;
  59 with Sinput.L; use Sinput.L;
  60 with Tbuild;   use Tbuild;
  61 with Types;    use Types;
  62
  63 procedure Frontend is
  64       Config_Pragmas : List_Id;
  65       --  Gather configuration pragmas
  66
  67 begin
  68    --  Carry out package initializations. These are initializations which
  69    --  might logically be performed at elaboration time, were it not for
  70    --  the fact that we may be doing things more than once in the big loop
  71    --  over files. Like elaboration, the order in which these calls are
  72    --  made is in some cases important. For example, Lib cannot be
  73    --  initialized until Namet, since it uses names table entries.
  74
  75    Rtsfind.Initialize;
  76    Atree.Initialize;
  77    Nlists.Initialize;
  78    Elists.Initialize;
  79    Lib.Load.Initialize;
  80    Sem_Ch8.Initialize;
  81    Fname.UF.Initialize;
  82    Checks.Initialize;
  83
  84    --  Create package Standard
  85
  86    CStand.Create_Standard;
  87
  88    --  Check possible symbol definitions specified by -gnateD switches
  89
  90    Prepcomp.Process_Command_Line_Symbol_Definitions;
  91
  92    --  If -gnatep= was specified, parse the preprocessing data file
  93
  94    if Preprocessing_Data_File /= null then
  95       Name_Len := Preprocessing_Data_File'Length;
  96       Name_Buffer (1 .. Name_Len) := Preprocessing_Data_File.all;
  97       Prepcomp.Parse_Preprocessing_Data_File (Name_Find);
  98
  99    --  Otherwise, check if there were preprocessing symbols on the command
 100    --  line and set preprocessing if there are.
 101
 102    else
 103       Prepcomp.Check_Symbols;
 104    end if;
 105
 106    --  Now that the preprocessing situation is established, we are able to
 107    --  load the main source (this is no longer done by Lib.Load.Initalize).
 108
 109    Lib.Load.Load_Main_Source;
 110
 111    --  Read and process configuration pragma files if present
 112
 113    declare
 114       Save_Style_Check : constant Boolean := Opt.Style_Check;
 115       --  Save style check mode so it can be restored later
 116
 117       Source_Config_File : Source_File_Index;
 118       --  Source reference for -gnatec configuration file
 119
 120       Prag : Node_Id;
 121
 122    begin
 123       --  We always analyze config files with style checks off, since
 124       --  we don't want a miscellaneous gnat.adc that is around to
 125       --  discombobulate intended -gnatg or -gnaty compilations. We
 126       --  also disconnect checking for maximum line length.
 127
 128       Opt.Style_Check := False;
 129       Style_Check := False;
 130
 131       --  Capture current suppress options, which may get modified
 132
 133       Scope_Suppress := Opt.Suppress_Options;
 134
 135       --  First deal with gnat.adc file
 136
 137       if Opt.Config_File then
 138          Name_Buffer (1 .. 8) := "gnat.adc";
 139          Name_Len := 8;
 140          Source_gnat_adc := Load_Config_File (Name_Enter);
 141
 142          if Source_gnat_adc /= No_Source_File then
 143             Initialize_Scanner (No_Unit, Source_gnat_adc);
 144             Config_Pragmas := Par (Configuration_Pragmas => True);
 145
 146          else
 147             Config_Pragmas := Empty_List;
 148          end if;
 149
 150       else
 151          Config_Pragmas := Empty_List;
 152       end if;
 153
 154       --  Now deal with specified config pragmas files if there are any
 155
 156       if Opt.Config_File_Names /= null then
 157          for Index in Opt.Config_File_Names'Range loop
 158             Name_Len := Config_File_Names (Index)'Length;
 159             Name_Buffer (1 .. Name_Len) := Config_File_Names (Index).all;
 160             Source_Config_File := Load_Config_File (Name_Enter);
 161
 162             if Source_Config_File = No_Source_File then
 163                Osint.Fail
 164                  ("cannot find configuration pragmas file ",
 165                   Config_File_Names (Index).all);
 166             end if;
 167
 168             Initialize_Scanner (No_Unit, Source_Config_File);
 169             Append_List_To
 170               (Config_Pragmas, Par (Configuration_Pragmas => True));
 171          end loop;
 172       end if;
 173
 174       --  Now analyze all pragmas except those whose analysis must be
 175       --  deferred till after the main unit is analyzed.
 176
 177       if Config_Pragmas /= Error_List
 178         and then Operating_Mode /= Check_Syntax
 179       then
 180          Prag := First (Config_Pragmas);
 181          while Present (Prag) loop
 182             if not Delay_Config_Pragma_Analyze (Prag) then
 183                Analyze_Pragma (Prag);
 184             end if;
 185
 186             Next (Prag);
 187          end loop;
 188       end if;
 189
 190       --  Restore style check, but if config file turned on checks, leave on!
 191
 192       Opt.Style_Check := Save_Style_Check or Style_Check;
 193
 194       --  Capture any modifications to suppress options from config pragmas
 195
 196       Opt.Suppress_Options := Scope_Suppress;
 197    end;
 198
 199    --  If there was a -gnatem switch, initialize the mappings of unit names to
 200    --  file names and of file names to path names from the mapping file.
 201
 202    if Mapping_File_Name /= null then
 203       Fmap.Initialize (Mapping_File_Name.all);
 204    end if;
 205
 206    --  We have now processed the command line switches, and the gnat.adc
 207    --  file, so this is the point at which we want to capture the values
 208    --  of the configuration switches (see Opt for further details).
 209
 210    Opt.Register_Opt_Config_Switches;
 211
 212    --  Initialize the scanner. Note that we do this after the call to
 213    --  Create_Standard, which uses the scanner in its processing of
 214    --  floating-point bounds.
 215
 216    Initialize_Scanner (Main_Unit, Source_Index (Main_Unit));
 217
 218    --  Output header if in verbose mode or full list mode
 219
 220    if Verbose_Mode or Full_List then
 221       Write_Eol;
 222
 223       if Operating_Mode = Generate_Code then
 224          Write_Str ("Compiling: ");
 225       else
 226          Write_Str ("Checking: ");
 227       end if;
 228
 229       Write_Name (Full_File_Name (Current_Source_File));
 230
 231       if not Debug_Flag_7 then
 232          Write_Str (" (source file time stamp: ");
 233          Write_Time_Stamp (Current_Source_File);
 234          Write_Char (')');
 235       end if;
 236
 237       Write_Eol;
 238    end if;
 239
 240    --  Here we call the parser to parse the compilation unit (or units in
 241    --  the check syntax mode, but in that case we won't go on to the
 242    --  semantics in any case).
 243
 244    Discard_List (Par (Configuration_Pragmas => False));
 245
 246    --  The main unit is now loaded, and subunits of it can be loaded,
 247    --  without reporting spurious loading circularities.
 248
 249    Set_Loading (Main_Unit, False);
 250
 251    --  Now that the main unit is installed, we can complete the analysis
 252    --  of the pragmas in gnat.adc and the configuration file, that require
 253    --  a context for their semantic processing.
 254
 255    if Config_Pragmas /= Error_List
 256      and then Operating_Mode /= Check_Syntax
 257    then
 258       --  Pragmas that require some semantic activity, such as
 259       --  Interrupt_State, cannot be processed until the main unit
 260       --  is installed, because they require a compilation unit on
 261       --  which to attach with_clauses, etc. So analyze them now.
 262
 263       declare
 264          Prag : Node_Id;
 265
 266       begin
 267          Prag := First (Config_Pragmas);
 268          while Present (Prag) loop
 269             if Delay_Config_Pragma_Analyze (Prag) then
 270                Analyze_Pragma (Prag);
 271             end if;
 272
 273             Next (Prag);
 274          end loop;
 275       end;
 276    end if;
 277
 278    --  Now on to the semantics. Skip if in syntax only mode
 279
 280    if Operating_Mode /= Check_Syntax then
 281
 282       --  Install the configuration pragmas in the tree
 283
 284       Set_Config_Pragmas (Aux_Decls_Node (Cunit (Main_Unit)), Config_Pragmas);
 285
 286       --  Following steps are skipped if we had a fatal error during parsing
 287
 288       if not Fatal_Error (Main_Unit) then
 289
 290          --  Reset Operating_Mode to Check_Semantics for subunits. We cannot
 291          --  actually generate code for subunits, so we suppress expansion.
 292          --  This also corrects certain problems that occur if we try to
 293          --  incorporate subunits at a lower level.
 294
 295          if Operating_Mode = Generate_Code
 296             and then Nkind (Unit (Cunit (Main_Unit))) = N_Subunit
 297          then
 298             Operating_Mode := Check_Semantics;
 299          end if;
 300
 301          --  Analyze (and possibly expand) main unit
 302
 303          Scope_Suppress := Suppress_Options;
 304          Semantics (Cunit (Main_Unit));
 305
 306          --  Cleanup processing after completing main analysis
 307
 308          if Operating_Mode = Generate_Code
 309             or else (Operating_Mode = Check_Semantics
 310                       and then ASIS_Mode)
 311          then
 312             Instantiate_Bodies;
 313          end if;
 314
 315          if Operating_Mode = Generate_Code then
 316             if Inline_Processing_Required then
 317                Analyze_Inlined_Bodies;
 318             end if;
 319
 320             --  Remove entities from program that do not have any
 321             --  execution time references.
 322
 323             if Debug_Flag_UU then
 324                Collect_Garbage_Entities;
 325             end if;
 326
 327             Check_Elab_Calls;
 328          end if;
 329
 330          --  List library units if requested
 331
 332          if List_Units then
 333             Lib.List;
 334          end if;
 335
 336          --  Output any messages for unreferenced entities
 337
 338          Output_Unreferenced_Messages;
 339          Sem_Warn.Check_Unused_Withs;
 340       end if;
 341    end if;
 342
 343    --  Qualify all entity names in inner packages, package bodies, etc.,
 344    --  except when compiling for the JVM back end, which depends on
 345    --  having unqualified names in certain cases and handles the
 346    --  generation of qualified names when needed.
 347
 348    if not Java_VM then
 349       Exp_Dbug.Qualify_All_Entity_Names;
 350    end if;
 351
 352    --  Dump the source now. Note that we do this as soon as the analysis
 353    --  of the tree is complete, because it is not just a dump in the case
 354    --  of -gnatD, where it rewrites all source locations in the tree.
 355
 356    Sprint.Source_Dump;
 357
 358    --  If a mapping file has been specified by a -gnatem switch, update
 359    --  it if there has been some sourcs that were not in the mappings.
 360
 361    if Mapping_File_Name /= null then
 362       Fmap.Update_Mapping_File (Mapping_File_Name.all);
 363    end if;
 364
 365    return;
 366 end Frontend;