1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
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 3, 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. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- This package contains routines for accessing and outputting the library
33 -- information. It contains the routine to load subsidiary units.
36 with Namet; use Namet;
38 with Types; use Types;
42 type Unit_Ref_Table is array (Pos range <>) of Unit_Number_Type;
43 -- Type to hold list of indirect references to unit number table
45 type Compiler_State_Type is (Parsing, Analyzing);
46 Compiler_State : Compiler_State_Type;
47 -- Indicates current state of compilation. This is used to implement the
48 -- function In_Extended_Main_Source_Unit.
50 Parsing_Main_Extended_Source : Boolean := False;
51 -- Set True if we are currently parsing a file that is part of the main
52 -- extended source (the main unit, its spec, or one of its subunits). This
53 -- flag to implement In_Extended_Main_Source_Unit.
55 Analysing_Subunit_Of_Main : Boolean := False;
56 -- Set to True when analyzing a subunit of the main source. When True, if
57 -- the subunit is preprocessed and -gnateG is specified, then the
58 -- preprocessed file (.prep) is written.
60 --------------------------------------------
61 -- General Approach to Library Management --
62 --------------------------------------------
64 -- As described in GNote #1, when a unit is compiled, all its subsidiary
65 -- units are recompiled, including the following:
67 -- (a) Corresponding spec for a body
68 -- (b) Parent spec of a child library spec
70 -- (d) Parent body of a subunit
71 -- (e) Subunits corresponding to any specified stubs
72 -- (f) Bodies of inlined subprograms that are called
73 -- (g) Bodies of generic subprograms or packages that are instantiated
74 -- (h) Bodies of packages containing either of the above two items
75 -- (i) Specs and bodies of runtime units
76 -- (j) Parent specs for with'ed child library units
78 -- If a unit is being compiled only for syntax checking, then no subsidiary
79 -- units are loaded, the syntax check applies only to the main unit,
80 -- i.e. the one contained in the source submitted to the library.
82 -- If a unit is being compiled for syntax and semantic checking, then only
83 -- cases (a)-(d) loads are performed, since the full semantic checking can
84 -- be carried out without needing (e)-(i) loads. In this case no object
85 -- file, or library information file, is generated, so the missing units
86 -- do not affect the results.
88 -- Specifications of library subprograms, subunits, and generic specs
89 -- and bodies, can only be compiled in syntax/semantic checking mode,
90 -- since no code is ever generated directly for these units. In the case
91 -- of subunits, only the compilation of the ultimate parent unit generates
92 -- actual code. If a subunit is submitted to the compiler in syntax/
93 -- semantic checking mode, the parent (or parents in the nested case) are
94 -- semantically checked only up to the point of the corresponding stub.
96 -- If code is being generated, then all the above units are required,
97 -- although the need for bodies of inlined procedures can be suppressed
98 -- by the use of a switch that sets the mode to ignore pragma Inline
101 -- The two main sections of the front end, Par and Sem, are recursive.
102 -- Compilation proceeds unit by unit making recursive calls as necessary.
103 -- The process is controlled from the GNAT main program, which makes calls
104 -- to Par and Sem sequence for the main unit.
106 -- Par parses the given unit, and then, after the parse is complete, uses
107 -- the Par.Load subprogram to load all its subsidiary units in categories
108 -- (a)-(d) above, installing pointers to the loaded units in the parse
109 -- tree, as described in a later section of this spec. If any of these
110 -- required units is missing, a fatal error is signalled, so that no
111 -- attempt is made to run Sem in such cases, since it is assumed that
112 -- too many cascaded errors would result, and the confusion would not
115 -- Following the call to Par on the main unit, the entire tree of required
116 -- units is thus loaded, and Sem is called on the main unit. The parameter
117 -- passed to Sem is the unit to be analyzed. The visibility table, which
118 -- is a single global structure, starts out containing only the entries
119 -- for the visible entities in Standard. Every call to Sem establishes a
120 -- new scope stack table, pushing an entry for Standard on entry to provide
121 -- the proper initial scope environment.
123 -- Sem first proceeds to perform semantic analysis on the currently loaded
126 -- In the case of a body (case (a) above), Sem analyzes the corresponding
127 -- spec, using a recursive call to Sem. As is always expected to be the
128 -- case with calls to Sem, any entities installed in the visibility table
129 -- are removed on exit from Sem, so that these entities have to be
130 -- reinstalled on return to continue the analysis of the body which of
131 -- course needs visibility of these entities.
133 -- In the case of the parent of a child spec (case (b) above), a similar
134 -- call is made to Sem to analyze the parent. Again, on return, the
135 -- entities from the analyzed parent spec have to be installed in the
136 -- visibility table of the caller (the child unit), which must have
137 -- visibility to the entities in its parent spec.
139 -- For with'ed specs (case (c) above), a recursive call to Sem is made
140 -- to analyze each spec in turn. After all the spec's have been analyzed,
141 -- but not till that point, the entities from all the with'ed units are
142 -- reinstalled in the visibility table so that the caller can proceed
143 -- with the analysis of the unit doing the with's with the necessary
144 -- entities made either potentially use visible or visible by selection
147 -- Case (d) arises when Sem is passed a subunit to analyze. This means
148 -- that the main unit is a subunit, and the unit passed to Sem is either
149 -- the main unit, or one of its ancestors that is still a subunit. Since
150 -- analysis must start at the top of the tree, Sem essentially cancels
151 -- the current call by immediately making a call to analyze the parent
152 -- (when this call is finished it immediately returns, so logically this
153 -- call is like a goto). The subunit will then be analyzed at the proper
154 -- time as described for the stub case. Note that we also turn off the
155 -- indication that code should be generated in this case, since the only
156 -- time we generate code for subunits is when compiling the main parent.
158 -- Case (e), subunits corresponding to stubs, are handled as the stubs
159 -- are encountered. There are three sub-cases:
161 -- If the subunit has already been loaded, then this means that the
162 -- main unit was a subunit, and we are back on our way down to it
163 -- after following the initial processing described for case (d).
164 -- In this case we analyze this particular subunit, as described
165 -- for the case where we are generating code, but when we get back
166 -- we are all done, since the rest of the parent is irrelevant. To
167 -- get out of the parent, we raise the exception Subunit_Found, which
168 -- is handled at the outer level of Sem.
170 -- The cases where the subunit has not already been loaded correspond
171 -- to cases where the main unit was a parent. In this case the action
172 -- depends on whether or not we are generating code. If we are not
173 -- generating code, then this is the case where we can simply ignore
174 -- the subunit, since in checking mode we don't even want to insist
175 -- that the subunit exist, much less waste time checking it.
177 -- If we are generating code, then we need to load and analyze
178 -- all subunits. This is achieved with a call to Lib.Load to load
179 -- and parse the unit, followed by processing that installs the
180 -- context clause of the subunit, analyzes the subunit, and then
181 -- removes the context clause (from the visibility chains of the
182 -- parent). Note that we do *not* do a recursive call to Sem in
183 -- this case, precisely because we need to do the analysis of the
184 -- subunit with the current visibility table and scope stack.
186 -- Case (f) applies only to subprograms for which a pragma Inline is
187 -- given, providing that the compiler is operating in the mode where
188 -- pragma Inline's are activated. When the expander encounters a call
189 -- to such a subprogram, it loads the body of the subprogram if it has
190 -- not already been loaded, and calls Sem to process it.
192 -- Case (g) is similar to case (f), except that the body of a generic
193 -- is unconditionally required, regardless of compiler mode settings.
194 -- As in the subprogram case, when the expander encounters a generic
195 -- instantiation, it loads the generic body of the subprogram if it
196 -- has not already been loaded, and calls Sem to process it.
198 -- Case (h) arises when a package contains either an inlined subprogram
199 -- which is called, or a generic which is instantiated. In this case the
200 -- body of the package must be loaded and analyzed with a call to Sem.
202 -- Case (i) is handled by adding implicit with clauses to the context
203 -- clauses of all units that potentially reference the relevant runtime
204 -- entities. Note that since we have the full set of units available,
205 -- the parser can always determine the set of runtime units that is
206 -- needed. These with clauses do not have associated use clauses, so
207 -- all references to the entities must be by selection. Once the with
208 -- clauses have been added, subsequent processing is as for normal
211 -- Case (j) is also handled by adding appropriate implicit with clauses
212 -- to any unit that withs a child unit. Again there is no use clause,
213 -- and subsequent processing proceeds as for an explicit with clause.
215 -- Sem thus completes the loading of all required units, except those
216 -- required for inline subprogram bodies or inlined generics. If any
217 -- of these load attempts fails, then the expander will not be called,
218 -- even if code was to be generated. If the load attempts all succeed
219 -- then the expander is called, though the attempt to generate code may
220 -- still fail if an error occurs during a load attempt for an inlined
221 -- body or a generic body.
223 -------------------------------------------
224 -- Special Handling of Subprogram Bodies --
225 -------------------------------------------
227 -- A subprogram body (in an adb file) may stand for both a spec and a body.
228 -- A simple model (and one that was adopted through version 2.07) is simply
229 -- to assume that such an adb file acts as its own spec if no ads file is
232 -- However, this is not correct. RM 10.1.4(4) requires that such a body
233 -- act as a spec unless a subprogram declaration of the same name is
234 -- already present. The correct interpretation of this in GNAT library
235 -- terms is to ignore an existing ads file of the same name unless this
236 -- ads file contains a subprogram declaration with the same name.
238 -- If there is an ads file with a unit other than a subprogram declaration
239 -- with the same name, then a fatal message is output, noting that this
240 -- irrelevant file must be deleted before the body can be compiled. See
241 -- ACVC test CA1020D to see how this processing is required.
247 Current_Sem_Unit : Unit_Number_Type := Main_Unit;
248 -- Unit number of unit currently being analyzed/expanded. This is set when
249 -- ever a new unit is entered, saving and restoring the old value, so that
250 -- it always reflects the unit currently being analyzed. The initial value
251 -- of Main_Unit ensures that a proper value is set initially, and in
252 -- particular for analysis of configuration pragmas in gnat.adc.
254 Main_Unit_Entity : Entity_Id;
255 -- Entity of main unit, same as Cunit_Entity (Main_Unit) except where
256 -- Main_Unit is a body with a separate spec, in which case it is the
257 -- entity for the spec.
263 -- The units table has an entry for each unit (source file) read in by the
264 -- current compilation. The table is indexed by the unit number value.
265 -- The first entry in the table, subscript Main_Unit, is for the main file.
266 -- Each entry in this units table contains the following data.
269 -- Pointer to the N_Compilation_Unit node. Initially set to Empty by
270 -- Lib.Load, and then reset to the required node by the parser when
271 -- the unit is parsed.
274 -- Pointer to the entity node for the compilation unit. Initially set
275 -- to Empty by Lib.Load, and then reset to the required entity by the
276 -- parser when the unit is parsed.
279 -- This is the number of the unit within the generated dependency
280 -- lines (D lines in the ALI file) which are sorted into alphabetical
281 -- order. The number is ones origin, so a value of 2 refers to the
282 -- second generated D line. The Dependency_Num values are set as the
283 -- D lines are generated, and are used to generate proper unit
284 -- references in the generated xref information and SCO output.
287 -- A flag indicating if this unit was compiled with dynamic elaboration
288 -- checks specified (as the result of using the -gnatE compilation
289 -- option or a pragma Elaboration_Checks (Dynamic)).
292 -- This is copied from the Sloc field of the Enode argument passed
293 -- to Load_Unit. It refers to the enclosing construct which caused
294 -- this unit to be loaded, e.g. most typically the with clause that
295 -- referenced the unit, and is used for error handling in Par.Load.
298 -- This is the expected unit name for a file other than the main unit,
299 -- since these are cases where we load the unit using Lib.Load and we
300 -- know the unit that is expected. It must be the same as Unit_Name
301 -- if it is set (see test in Par.Load). Expected_Unit is set to
302 -- No_Name for the main unit.
305 -- A flag that is initialized to None and gets set to Errorif a fatal
306 -- error occurs during the processing of a unit. A fatal error is one
307 -- defined as serious enough to stop the next phase of the compiler
308 -- from running (i.e. fatal error during parsing stops semantics,
309 -- fatal error during semantics stops code generation). Note that
310 -- currently, errors of any kind cause Fatal_Error to be set, but
311 -- eventually perhaps only errors labeled as fatal errors should be
312 -- this severe if we decide to try Sem on sources with minor errors.
313 -- There are three settings (see declaration of Fatal_Type).
316 -- This flag is set True for all units in the current file for which
317 -- code is to be generated. This includes the unit explicitly compiled,
318 -- together with its specification, and any subunits.
321 -- A Boolean flag, initially set to False when a unit entry is created,
322 -- and set to True if the unit defines a remote access to class wide
323 -- (RACW) object. This is used for controlling generation of the RA
324 -- attribute in the ali file.
327 -- N_String_Literal node from a valid pragma Ident that applies to
328 -- this unit. If no Ident pragma applies to the unit, then Empty.
331 -- A flag that is used to catch circular WITH dependencies. It is set
332 -- True when an entry is initially created in the file table, and set
333 -- False when the load is completed, or ends with an error.
336 -- This field is used to indicate the priority of a possible main
337 -- program, as set by a pragma Priority. A value of -1 indicates
338 -- that the default priority is to be used (and is also used for
339 -- entries that do not correspond to possible main programs).
342 -- This field is used to indicate the affinity of a possible main
343 -- program, as set by a pragma CPU. A value of -1 indicates
344 -- that the default affinity is to be used (and is also used for
345 -- entries that do not correspond to possible main programs).
348 -- The index of the unit within the file for multiple unit per file
349 -- mode. Set to zero in normal single unit per file mode.
352 -- A flag set when a pragma or aspect No_Elaboration_Code_All applies
353 -- to the unit. This is used to implement the transitive WITH rules
354 -- (and for no other purpose).
357 -- This is a character field containing L if Optimize_Alignment mode
358 -- was set locally, and O/T/S for Off/Time/Space default if not.
361 -- This field holds a serial number used by New_Internal_Name to
362 -- generate unique temporary numbers on a unit by unit basis. The
363 -- only access to this field is via the Increment_Serial_Number
364 -- routine which increments the current value and returns it. This
365 -- serial number is separate for each unit.
368 -- The index in the source file table of the corresponding source file.
369 -- Set when the entry is created by a call to Lib.Load and then cannot
373 -- The name of the source file containing the unit. Set when the entry
374 -- is created by a call to Lib.Load, and then cannot be changed.
377 -- The name of the unit. Initialized to No_Name by Lib.Load, and then
378 -- set by the parser when the unit is parsed to the unit name actually
379 -- found in the file (which should, in the absence of errors) be the
380 -- same name as Expected_Unit.
383 -- This field holds the version of the unit, which is computed as
384 -- the exclusive or of the checksums of this unit, and all its
385 -- semantically dependent units. Access to the version number field
386 -- is not direct, but is done through the routines described below.
387 -- When a unit table entry is created, this field is initialized to
388 -- the checksum of the corresponding source file. Version_Update is
389 -- then called to reflect the contributions of any unit on which this
390 -- unit is semantically dependent.
392 -- The units table is reset to empty at the start of the compilation of
393 -- each main unit by Lib.Initialize. Entries are then added by calls to
394 -- the Lib.Load procedure. The following subprograms are used to access
395 -- and modify entries in the Units table. Individual entries are accessed
396 -- using a unit number value which ranges from Main_Unit (the first entry,
397 -- which is always for the current main unit) to Last_Unit.
399 Default_Main_Priority : constant Int := -1;
400 -- Value used in Main_Priority field to indicate default main priority
402 Default_Main_CPU : constant Int := -1;
403 -- Value used in Main_CPU field to indicate default main affinity
405 -- The following defines settings for the Fatal_Error field
409 -- No error detected for this unit
412 -- Fatal error detected that prevents moving to the next phase. For
413 -- example, a fatal error during parsing inhibits semantic analysis.
416 -- A fatal error was detected, but we are in Try_Semantics mode (as set
417 -- by -gnatq or -gnatQ). This does not stop the compiler from proceding,
418 -- but tools can use this status (e.g. ASIS looking at the generated
419 -- tree) to know that a fatal error was detected.
421 function Cunit (U : Unit_Number_Type) return Node_Id;
422 function Cunit_Entity (U : Unit_Number_Type) return Entity_Id;
423 function Dependency_Num (U : Unit_Number_Type) return Nat;
424 function Dynamic_Elab (U : Unit_Number_Type) return Boolean;
425 function Error_Location (U : Unit_Number_Type) return Source_Ptr;
426 function Expected_Unit (U : Unit_Number_Type) return Unit_Name_Type;
427 function Fatal_Error (U : Unit_Number_Type) return Fatal_Type;
428 function Generate_Code (U : Unit_Number_Type) return Boolean;
429 function Ident_String (U : Unit_Number_Type) return Node_Id;
430 function Has_RACW (U : Unit_Number_Type) return Boolean;
431 function Loading (U : Unit_Number_Type) return Boolean;
432 function Main_CPU (U : Unit_Number_Type) return Int;
433 function Main_Priority (U : Unit_Number_Type) return Int;
434 function Munit_Index (U : Unit_Number_Type) return Nat;
435 function No_Elab_Code_All (U : Unit_Number_Type) return Boolean;
436 function OA_Setting (U : Unit_Number_Type) return Character;
437 function Source_Index (U : Unit_Number_Type) return Source_File_Index;
438 function Unit_File_Name (U : Unit_Number_Type) return File_Name_Type;
439 function Unit_Name (U : Unit_Number_Type) return Unit_Name_Type;
440 -- Get value of named field from given units table entry
442 procedure Set_Cunit (U : Unit_Number_Type; N : Node_Id);
443 procedure Set_Cunit_Entity (U : Unit_Number_Type; E : Entity_Id);
444 procedure Set_Dynamic_Elab (U : Unit_Number_Type; B : Boolean := True);
445 procedure Set_Error_Location (U : Unit_Number_Type; W : Source_Ptr);
446 procedure Set_Fatal_Error (U : Unit_Number_Type; V : Fatal_Type);
447 procedure Set_Generate_Code (U : Unit_Number_Type; B : Boolean := True);
448 procedure Set_Has_RACW (U : Unit_Number_Type; B : Boolean := True);
449 procedure Set_Ident_String (U : Unit_Number_Type; N : Node_Id);
450 procedure Set_Loading (U : Unit_Number_Type; B : Boolean := True);
451 procedure Set_Main_CPU (U : Unit_Number_Type; P : Int);
452 procedure Set_No_Elab_Code_All (U : Unit_Number_Type; B : Boolean := True);
453 procedure Set_Main_Priority (U : Unit_Number_Type; P : Int);
454 procedure Set_OA_Setting (U : Unit_Number_Type; C : Character);
455 procedure Set_Unit_Name (U : Unit_Number_Type; N : Unit_Name_Type);
456 -- Set value of named field for given units table entry. Note that we
457 -- do not have an entry for each possible field, since some of the fields
458 -- can only be set by specialized interfaces (defined below).
460 function Compilation_Switches_Last return Nat;
461 -- Return the count of stored compilation switches
463 procedure Disable_Switch_Storing;
464 -- Disable registration of switches by Store_Compilation_Switch. Used to
465 -- avoid registering switches added automatically by the gcc driver at the
466 -- end of the command line.
468 function Earlier_In_Extended_Unit (S1, S2 : Source_Ptr) return Boolean;
469 -- Given two Sloc values for which In_Same_Extended_Unit is true, determine
470 -- if S1 appears before S2. Returns True if S1 appears before S2, and False
471 -- otherwise. The result is undefined if S1 and S2 are not in the same
472 -- extended unit. Note: this routine will not give reliable results if
473 -- called after Sprint has been called with -gnatD set.
475 procedure Enable_Switch_Storing;
476 -- Enable registration of switches by Store_Compilation_Switch. Used to
477 -- avoid registering switches added automatically by the gcc driver at the
478 -- beginning of the command line.
480 function Entity_Is_In_Main_Unit (E : Entity_Id) return Boolean;
481 -- Returns True if the entity E is declared in the main unit, or, in
482 -- its corresponding spec, or one of its subunits. Entities declared
483 -- within generic instantiations return True if the instantiation is
484 -- itself "in the main unit" by this definition. Otherwise False.
486 function Exact_Source_Name (Loc : Source_Ptr) return String;
487 -- Return name of entity at location Loc exactly as written in the source.
488 -- This includes copying the wide character encodings exactly as they were
489 -- used in the source, so the caller must be aware of the possibility of
492 function Get_Compilation_Switch (N : Pos) return String_Ptr;
493 -- Return the Nth stored compilation switch, or null if less than N
494 -- switches have been stored. Used by ASIS and back ends written in Ada.
496 function Generic_May_Lack_ALI (Sfile : File_Name_Type) return Boolean;
497 -- Generic units must be separately compiled. Since we always use
498 -- macro substitution for generics, the resulting object file is a dummy
499 -- one with no code, but the ALI file has the normal form, and we need
500 -- this ALI file so that the binder can work out a correct order of
503 -- However, ancient versions of GNAT used to not generate code or ALI
504 -- files for generic units, and this would yield complex order of
505 -- elaboration issues. These were fixed in GNAT 3.10. The support for not
506 -- compiling language-defined library generics was retained nonetheless
507 -- to facilitate bootstrap. Specifically, it is convenient to have
508 -- the same list of files to be compiled for all stages. So, if the
509 -- bootstrap compiler does not generate code for a given file, then
510 -- the stage1 compiler (and binder) also must deal with the case of
511 -- that file not being compiled. The predicate Generic_May_Lack_ALI is
512 -- True for those generic units for which missing ALI files are allowed.
514 function Get_Cunit_Unit_Number (N : Node_Id) return Unit_Number_Type;
515 -- Return unit number of the unit whose N_Compilation_Unit node is the
516 -- one passed as an argument. This must always succeed since the node
517 -- could not have been built without making a unit table entry.
519 function Get_Cunit_Entity_Unit_Number
520 (E : Entity_Id) return Unit_Number_Type;
521 -- Return unit number of the unit whose compilation unit spec entity is
522 -- the one passed as an argument. This must always succeed since the
523 -- entity could not have been built without making a unit table entry.
525 function Get_Source_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type;
526 pragma Inline (Get_Source_Unit);
527 function Get_Source_Unit (S : Source_Ptr) return Unit_Number_Type;
528 -- Return unit number of file identified by given source pointer value.
529 -- This call must always succeed, since any valid source pointer value
530 -- belongs to some previously loaded module. If the given source pointer
531 -- value is within an instantiation, this function returns the unit number
532 -- of the template, i.e. the unit containing the source code corresponding
533 -- to the given Source_Ptr value. The version taking a Node_Id argument, N,
534 -- simply applies the function to Sloc (N).
536 function Get_Code_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type;
537 pragma Inline (Get_Code_Unit);
538 function Get_Code_Unit (S : Source_Ptr) return Unit_Number_Type;
539 -- This is like Get_Source_Unit, except that in the instantiation case,
540 -- it uses the location of the top level instantiation, rather than the
541 -- template, so it returns the unit number containing the code that
542 -- corresponds to the node N, or the source location S.
544 function Get_Top_Level_Code_Unit
545 (N : Node_Or_Entity_Id) return Unit_Number_Type;
546 pragma Inline (Get_Code_Unit);
547 function Get_Top_Level_Code_Unit (S : Source_Ptr) return Unit_Number_Type;
548 -- This is like Get_Code_Unit, except that in the case of subunits, it
549 -- returns the top-level unit to which the subunit belongs instead of
552 -- Note: for nodes and slocs in declarations of library-level instances of
553 -- generics these routines wrongly return the unit number corresponding to
554 -- the body of the instance. In effect, locations of SPARK references in
555 -- ALI files are bogus. However, fixing this is not worth the effort, since
556 -- these references are only used for debugging.
558 function In_Extended_Main_Code_Unit
559 (N : Node_Or_Entity_Id) return Boolean;
560 -- Return True if the node is in the generated code of the extended main
561 -- unit, defined as the main unit, its specification (if any), and all
562 -- its subunits (considered recursively). Units for which this enquiry
563 -- returns True are those for which code will be generated. Nodes from
564 -- instantiations are included in the extended main unit for this call.
565 -- If the main unit is itself a subunit, then the extended main code unit
566 -- includes its parent unit, and the parent unit spec if it is separate.
568 -- This routine (and the following three routines) all return False if
569 -- Sloc (N) is No_Location or Standard_Location. In an earlier version,
570 -- they returned True for Standard_Location, but this was odd, and some
571 -- archeology indicated that this was done for the sole benefit of the
572 -- call in Restrict.Check_Restriction_No_Dependence, so we have moved
573 -- the special case check to that routine. This avoids some difficulties
574 -- with some other calls that malfunctioned with the odd return of True.
576 function In_Extended_Main_Code_Unit (Loc : Source_Ptr) return Boolean;
577 -- Same function as above, but argument is a source pointer rather
580 function In_Extended_Main_Source_Unit
581 (N : Node_Or_Entity_Id) return Boolean;
582 -- Return True if the node is in the source text of the extended main
583 -- unit, defined as the main unit, its specification (if any), and all
584 -- its subunits (considered recursively). Units for which this enquiry
585 -- returns True are those for which code will be generated. This differs
586 -- from In_Extended_Main_Code_Unit only in that instantiations are not
587 -- included for the purposes of this call. If the main unit is itself
588 -- a subunit, then the extended main source unit includes its parent unit,
589 -- and the parent unit spec if it is separate.
591 function In_Extended_Main_Source_Unit (Loc : Source_Ptr) return Boolean;
592 -- Same function as above, but argument is a source pointer
594 function In_Predefined_Unit (N : Node_Or_Entity_Id) return Boolean;
595 -- Returns True if the given node or entity appears within the source text
596 -- of a predefined unit (i.e. within Ada, Interfaces, System or within one
597 -- of the descendant packages of one of these three packages).
599 function In_Predefined_Unit (S : Source_Ptr) return Boolean;
600 -- Same function as above but argument is a source pointer
602 function In_Same_Code_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
603 pragma Inline (In_Same_Code_Unit);
604 -- Determines if the two nodes or entities N1 and N2 are in the same
605 -- code unit, the criterion being that Get_Code_Unit yields the same
606 -- value for each argument.
608 function In_Same_Extended_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
609 pragma Inline (In_Same_Extended_Unit);
610 -- Determines if two nodes or entities N1 and N2 are in the same
611 -- extended unit, where an extended unit is defined as a unit and all
612 -- its subunits (considered recursively, i.e. subunits of subunits are
613 -- included). Returns true if S1 and S2 are in the same extended unit
614 -- and False otherwise.
616 function In_Same_Extended_Unit (S1, S2 : Source_Ptr) return Boolean;
617 pragma Inline (In_Same_Extended_Unit);
618 -- Determines if the two source locations S1 and S2 are in the same
619 -- extended unit, where an extended unit is defined as a unit and all
620 -- its subunits (considered recursively, i.e. subunits of subunits are
621 -- included). Returns true if S1 and S2 are in the same extended unit
622 -- and False otherwise.
624 function In_Same_Source_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean;
625 pragma Inline (In_Same_Source_Unit);
626 -- Determines if the two nodes or entities N1 and N2 are in the same
627 -- source unit, the criterion being that Get_Source_Unit yields the
628 -- same value for each argument.
630 function Increment_Serial_Number return Nat;
631 -- Increment Serial_Number field for current unit, and return the
632 -- incremented value.
634 procedure Initialize;
635 -- Initialize internal tables
637 function Is_Loaded (Uname : Unit_Name_Type) return Boolean;
638 -- Determines if unit with given name is already loaded, i.e. there is
639 -- already an entry in the file table with this unit name for which the
640 -- corresponding file was found and parsed. Note that the Fatal_Error value
641 -- of this entry must be checked before proceeding with further processing.
643 function Last_Unit return Unit_Number_Type;
644 -- Unit number of last allocated unit
646 procedure List (File_Names_Only : Boolean := False);
647 -- Lists units in active library (i.e. generates output consisting of a
648 -- sorted listing of the units represented in File table, except for the
649 -- main unit). If File_Names_Only is set to True, then the list includes
650 -- only file names, and no other information. Otherwise the unit name and
651 -- time stamp are also output. File_Names_Only also restricts the list to
652 -- exclude any predefined files.
655 -- Lock internal tables before calling back end
657 function Num_Units return Nat;
658 -- Number of units currently in unit table
660 procedure Remove_Unit (U : Unit_Number_Type);
661 -- Remove unit U from unit table. Currently this is effective only if U is
662 -- the last unit currently stored in the unit table.
664 procedure Replace_Linker_Option_String
666 Match_String : String);
667 -- Replace an existing Linker_Option if the prefix Match_String matches,
668 -- otherwise call Store_Linker_Option_String.
670 procedure Store_Compilation_Switch (Switch : String);
671 -- Called to register a compilation switch, either front-end or back-end,
672 -- which may influence the generated output file(s). Switch is the text of
673 -- the switch to store (except that -fRTS gets changed back to --RTS).
675 procedure Store_Linker_Option_String (S : String_Id);
676 -- This procedure is called to register the string from a pragma
677 -- Linker_Option. The argument is the Id of the string to register.
679 procedure Store_Note (N : Node_Id);
680 -- This procedure is called to register a pragma N for which a notes
681 -- entry is required.
683 procedure Synchronize_Serial_Number;
684 -- This function increments the Serial_Number field for the current unit
685 -- but does not return the incremented value. This is used when there
686 -- is a situation where one path of control increments a serial number
687 -- (using Increment_Serial_Number), and the other path does not and it is
688 -- important to keep the serial numbers synchronized in the two cases (e.g.
689 -- when the references in a package and a client must be kept consistent).
692 -- Initializes internal tables from current tree file using the relevant
693 -- Table.Tree_Read routines.
695 procedure Tree_Write;
696 -- Writes out internal tables to current tree file using the relevant
697 -- Table.Tree_Write routines.
700 -- Unlock internal tables, in cases where the back end needs to modify them
702 function Version_Get (U : Unit_Number_Type) return Word_Hex_String;
703 -- Returns the version as a string with 8 hex digits (upper case letters)
705 procedure Version_Referenced (S : String_Id);
706 -- This routine is called from Exp_Attr to register the use of a Version
707 -- or Body_Version attribute. The argument is the external name used to
708 -- access the version string.
710 procedure Write_Unit_Info
711 (Unit_Num : Unit_Number_Type;
713 Prefix : String := "";
714 Withs : Boolean := False);
715 -- Print out debugging information about the unit. Prefix precedes the rest
716 -- of the printout. If Withs is True, we print out units with'ed by this
717 -- unit (not counting limited withs).
719 ---------------------------------------------------------------
720 -- Special Handling for Restriction_Set (No_Dependence) Case --
721 ---------------------------------------------------------------
723 -- If we have a Restriction_Set attribute for No_Dependence => unit,
724 -- and the unit is not given in a No_Dependence restriction that we
725 -- can see, the attribute will return False.
727 -- We have to ensure in this case that the binder will reject any attempt
728 -- to set a No_Dependence restriction in some other unit in the partition.
730 -- If the unit is in the semantic closure, then of course it is properly
731 -- WITH'ed by someone, and the binder will do this job automatically as
732 -- part of its normal processing.
734 -- But if the unit is not in the semantic closure, we must make sure the
735 -- binder knows about it. The use of the Restriction_Set attribute giving
736 -- a result of False does not mean of itself that we have to include the
737 -- unit in the partition. So what we do is to generate a with (W) line in
738 -- the ali file (with no file name information), but no corresponding D
739 -- (dependency) line. This is recognized by the binder as meaning "Don't
740 -- let anyone specify No_Dependence for this unit, but you don't have to
741 -- include it if there is no real W line for the unit".
743 -- The following table keeps track of relevant units. It is used in the
744 -- Lib.Writ circuit for outputting With lines to output the special with
745 -- line with RA if the unit is not in the semantic closure.
747 package Restriction_Set_Dependences is new Table.Table (
748 Table_Component_Type => Unit_Name_Type,
749 Table_Index_Type => Int,
750 Table_Low_Bound => 0,
752 Table_Increment => 100,
753 Table_Name => "Restriction_Attribute_Dependences");
756 pragma Inline (Cunit);
757 pragma Inline (Cunit_Entity);
758 pragma Inline (Dependency_Num);
759 pragma Inline (Fatal_Error);
760 pragma Inline (Generate_Code);
761 pragma Inline (Has_RACW);
762 pragma Inline (Increment_Serial_Number);
763 pragma Inline (Loading);
764 pragma Inline (Main_CPU);
765 pragma Inline (Main_Priority);
766 pragma Inline (Munit_Index);
767 pragma Inline (No_Elab_Code_All);
768 pragma Inline (OA_Setting);
769 pragma Inline (Set_Cunit);
770 pragma Inline (Set_Cunit_Entity);
771 pragma Inline (Set_Fatal_Error);
772 pragma Inline (Set_Generate_Code);
773 pragma Inline (Set_Has_RACW);
774 pragma Inline (Set_Loading);
775 pragma Inline (Set_Main_CPU);
776 pragma Inline (Set_Main_Priority);
777 pragma Inline (Set_No_Elab_Code_All);
778 pragma Inline (Set_OA_Setting);
779 pragma Inline (Set_Unit_Name);
780 pragma Inline (Source_Index);
781 pragma Inline (Unit_File_Name);
782 pragma Inline (Unit_Name);
786 type Unit_Record is record
787 Unit_File_Name : File_Name_Type;
788 Unit_Name : Unit_Name_Type;
790 Expected_Unit : Unit_Name_Type;
791 Source_Index : Source_File_Index;
793 Cunit_Entity : Entity_Id;
794 Dependency_Num : Int;
795 Ident_String : Node_Id;
800 Error_Location : Source_Ptr;
801 Fatal_Error : Fatal_Type;
802 Generate_Code : Boolean;
804 Dynamic_Elab : Boolean;
805 No_Elab_Code_All : Boolean;
808 OA_Setting : Character;
809 SPARK_Mode_Pragma : Node_Id;
812 -- The following representation clause ensures that the above record
813 -- has no holes. We do this so that when instances of this record are
814 -- written by Tree_Gen, we do not write uninitialized values to the file.
816 for Unit_Record use record
817 Unit_File_Name at 0 range 0 .. 31;
818 Unit_Name at 4 range 0 .. 31;
819 Munit_Index at 8 range 0 .. 31;
820 Expected_Unit at 12 range 0 .. 31;
821 Source_Index at 16 range 0 .. 31;
822 Cunit at 20 range 0 .. 31;
823 Cunit_Entity at 24 range 0 .. 31;
824 Dependency_Num at 28 range 0 .. 31;
825 Ident_String at 32 range 0 .. 31;
826 Main_Priority at 36 range 0 .. 31;
827 Main_CPU at 40 range 0 .. 31;
828 Serial_Number at 44 range 0 .. 31;
829 Version at 48 range 0 .. 31;
830 Error_Location at 52 range 0 .. 31;
831 Fatal_Error at 56 range 0 .. 7;
832 Generate_Code at 57 range 0 .. 7;
833 Has_RACW at 58 range 0 .. 7;
834 Dynamic_Elab at 59 range 0 .. 7;
835 No_Elab_Code_All at 60 range 0 .. 7;
836 Filler at 61 range 0 .. 7;
837 OA_Setting at 62 range 0 .. 7;
838 Loading at 63 range 0 .. 7;
839 SPARK_Mode_Pragma at 64 range 0 .. 31;
842 for Unit_Record'Size use 68 * 8;
843 -- This ensures that we did not leave out any fields
845 package Units is new Table.Table (
846 Table_Component_Type => Unit_Record,
847 Table_Index_Type => Unit_Number_Type,
848 Table_Low_Bound => Main_Unit,
849 Table_Initial => Alloc.Units_Initial,
850 Table_Increment => Alloc.Units_Increment,
851 Table_Name => "Units");
853 -- The following table stores strings from pragma Linker_Option lines
855 type Linker_Option_Entry is record
857 -- The string for the linker option line
859 Unit : Unit_Number_Type;
860 -- The unit from which the linker option comes
863 package Linker_Option_Lines is new Table.Table (
864 Table_Component_Type => Linker_Option_Entry,
865 Table_Index_Type => Integer,
866 Table_Low_Bound => 1,
867 Table_Initial => Alloc.Linker_Option_Lines_Initial,
868 Table_Increment => Alloc.Linker_Option_Lines_Increment,
869 Table_Name => "Linker_Option_Lines");
871 -- The following table stores references to pragmas that generate Notes
873 package Notes is new Table.Table (
874 Table_Component_Type => Node_Id,
875 Table_Index_Type => Integer,
876 Table_Low_Bound => 1,
877 Table_Initial => Alloc.Notes_Initial,
878 Table_Increment => Alloc.Notes_Increment,
879 Table_Name => "Notes");
881 -- The following table records the compilation switches used to compile
882 -- the main unit. The table includes only switches. It excludes -o
883 -- switches as well as artifacts of the gcc/gnat1 interface such as
884 -- -quiet, -dumpbase, or -auxbase.
886 -- This table is set as part of the compiler argument scanning in
887 -- Back_End. It can also be reset in -gnatc mode from the data in an
888 -- existing ali file, and is read and written by the Tree_Read and
889 -- Tree_Write routines for ASIS.
891 package Compilation_Switches is new Table.Table (
892 Table_Component_Type => String_Ptr,
893 Table_Index_Type => Nat,
894 Table_Low_Bound => 1,
896 Table_Increment => 100,
897 Table_Name => "Compilation_Switches");
899 Load_Msg_Sloc : Source_Ptr;
900 -- Location for placing error messages (a token in the main source text)
901 -- This is set from Sloc (Enode) by Load only in the case where this Sloc
902 -- is in the main source file. This ensures that not found messages and
903 -- circular dependency messages reference the original with in this source.
905 type Load_Stack_Entry is record
906 Unit_Number : Unit_Number_Type;
910 -- The Load_Stack table contains a list of unit numbers (indexes into the
911 -- unit table) of units being loaded on a single dependency chain, and a
912 -- flag to indicate whether this unit is loaded through a limited_with
913 -- clause. The First entry is the main unit. The second entry, if present
914 -- is a unit on which the first unit depends, etc. This stack is used to
915 -- generate error messages showing the dependency chain if a file is not
916 -- found, or whether a true circular dependency exists. The Load_Unit
917 -- function makes an entry in this table when it is called, and removes
918 -- the entry just before it returns.
920 package Load_Stack is new Table.Table (
921 Table_Component_Type => Load_Stack_Entry,
922 Table_Index_Type => Int,
923 Table_Low_Bound => 0,
924 Table_Initial => Alloc.Load_Stack_Initial,
925 Table_Increment => Alloc.Load_Stack_Increment,
926 Table_Name => "Load_Stack");
928 procedure Sort (Tbl : in out Unit_Ref_Table);
929 -- This procedure sorts the given unit reference table in order of
930 -- ascending unit names, where the ordering relation is as described
931 -- by the comparison routines provided by package Uname.
933 -- The Version_Ref table records Body_Version and Version attribute
934 -- references. The entries are simply the strings for the external
935 -- names that correspond to the referenced values.
937 package Version_Ref is new Table.Table (
938 Table_Component_Type => String_Id,
939 Table_Index_Type => Nat,
940 Table_Low_Bound => 1,
942 Table_Increment => 100,
943 Table_Name => "Version_Ref");