1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2012, 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 -- The name of the source file containing the unit. Set when the entry
270 -- is created by a call to Lib.Load, and then cannot be changed.
273 -- The index in the source file table of the corresponding source file.
274 -- Set when the entry is created by a call to Lib.Load and then cannot
278 -- The index of the unit within the file for multiple unit per file
279 -- mode. Set to zero in normal single unit per file mode.
282 -- This is copied from the Sloc field of the Enode argument passed
283 -- to Load_Unit. It refers to the enclosing construct which caused
284 -- this unit to be loaded, e.g. most typically the with clause that
285 -- referenced the unit, and is used for error handling in Par.Load.
288 -- This is the expected unit name for a file other than the main unit,
289 -- since these are cases where we load the unit using Lib.Load and we
290 -- know the unit that is expected. It must be the same as Unit_Name
291 -- if it is set (see test in Par.Load). Expected_Unit is set to
292 -- No_Name for the main unit.
295 -- The name of the unit. Initialized to No_Name by Lib.Load, and then
296 -- set by the parser when the unit is parsed to the unit name actually
297 -- found in the file (which should, in the absence of errors) be the
298 -- same name as Expected_Unit.
301 -- Pointer to the N_Compilation_Unit node. Initially set to Empty by
302 -- Lib.Load, and then reset to the required node by the parser when
303 -- the unit is parsed.
306 -- Pointer to the entity node for the compilation unit. Initially set
307 -- to Empty by Lib.Load, and then reset to the required entity by the
308 -- parser when the unit is parsed.
311 -- This is the number of the unit within the generated dependency
312 -- lines (D lines in the ALI file) which are sorted into alphabetical
313 -- order. The number is ones origin, so a value of 2 refers to the
314 -- second generated D line. The Dependency_Number values are set
315 -- as the D lines are generated, and are used to generate proper
316 -- unit references in the generated xref information and SCO output.
319 -- A flag indicating if this unit was compiled with dynamic elaboration
320 -- checks specified (as the result of using the -gnatE compilation
321 -- option or a pragma Elaboration_Checks (Dynamic).
324 -- A flag that is initialized to False, and gets set to True if a fatal
325 -- error occurs during the processing of a unit. A fatal error is one
326 -- defined as serious enough to stop the next phase of the compiler
327 -- from running (i.e. fatal error during parsing stops semantics,
328 -- fatal error during semantics stops code generation). Note that
329 -- currently, errors of any kind cause Fatal_Error to be set, but
330 -- eventually perhaps only errors labeled as Fatal_Errors should be
331 -- this severe if we decide to try Sem on sources with minor errors.
334 -- This flag is set True for all units in the current file for which
335 -- code is to be generated. This includes the unit explicitly compiled,
336 -- together with its specification, and any subunits.
339 -- A Boolean flag, initially set to False when a unit entry is created,
340 -- and set to True if the unit defines a remote access to class wide
341 -- (RACW) object. This is used for controlling generation of the RA
342 -- attribute in the ali file.
345 -- A Boolean flag, initially set False by default, set to True if a
346 -- pragma Compiler_Unit appears in the unit.
349 -- N_String_Literal node from a valid pragma Ident that applies to
350 -- this unit. If no Ident pragma applies to the unit, then Empty.
353 -- A flag that is used to catch circular WITH dependencies. It is set
354 -- True when an entry is initially created in the file table, and set
355 -- False when the load is completed, or ends with an error.
358 -- This field is used to indicate the priority of a possible main
359 -- program, as set by a pragma Priority. A value of -1 indicates
360 -- that the default priority is to be used (and is also used for
361 -- entries that do not correspond to possible main programs).
364 -- This field is used to indicate the affinity of a possible main
365 -- program, as set by a pragma CPU. A value of -1 indicates
366 -- that the default affinity is to be used (and is also used for
367 -- entries that do not correspond to possible main programs).
370 -- This flag is set if a subprogram unit has an allocator after the
371 -- BEGIN (it is used to set the AB flag in the M ALI line).
374 -- This is a character field containing L if Optimize_Alignment mode
375 -- was set locally, and O/T/S for Off/Time/Space default if not.
378 -- This field holds a serial number used by New_Internal_Name to
379 -- generate unique temporary numbers on a unit by unit basis. The
380 -- only access to this field is via the Increment_Serial_Number
381 -- routine which increments the current value and returns it. This
382 -- serial number is separate for each unit.
385 -- This field holds the version of the unit, which is computed as
386 -- the exclusive or of the checksums of this unit, and all its
387 -- semantically dependent units. Access to the version number field
388 -- is not direct, but is done through the routines described below.
389 -- When a unit table entry is created, this field is initialized to
390 -- the checksum of the corresponding source file. Version_Update is
391 -- then called to reflect the contributions of any unit on which this
392 -- unit is semantically dependent.
394 -- The units table is reset to empty at the start of the compilation of
395 -- each main unit by Lib.Initialize. Entries are then added by calls to
396 -- the Lib.Load procedure. The following subprograms are used to access
397 -- and modify entries in the Units table. Individual entries are accessed
398 -- using a unit number value which ranges from Main_Unit (the first entry,
399 -- which is always for the current main unit) to Last_Unit.
401 Default_Main_Priority
: constant Int
:= -1;
402 -- Value used in Main_Priority field to indicate default main priority
404 Default_Main_CPU
: constant Int
:= -1;
405 -- Value used in Main_CPU field to indicate default main affinity
407 function Cunit
(U
: Unit_Number_Type
) return Node_Id
;
408 function Cunit_Entity
(U
: Unit_Number_Type
) return Entity_Id
;
409 function Dependency_Num
(U
: Unit_Number_Type
) return Nat
;
410 function Dynamic_Elab
(U
: Unit_Number_Type
) return Boolean;
411 function Error_Location
(U
: Unit_Number_Type
) return Source_Ptr
;
412 function Expected_Unit
(U
: Unit_Number_Type
) return Unit_Name_Type
;
413 function Fatal_Error
(U
: Unit_Number_Type
) return Boolean;
414 function Generate_Code
(U
: Unit_Number_Type
) return Boolean;
415 function Ident_String
(U
: Unit_Number_Type
) return Node_Id
;
416 function Has_Allocator
(U
: Unit_Number_Type
) return Boolean;
417 function Has_RACW
(U
: Unit_Number_Type
) return Boolean;
418 function Is_Compiler_Unit
(U
: Unit_Number_Type
) return Boolean;
419 function Loading
(U
: Unit_Number_Type
) return Boolean;
420 function Main_CPU
(U
: Unit_Number_Type
) return Int
;
421 function Main_Priority
(U
: Unit_Number_Type
) return Int
;
422 function Munit_Index
(U
: Unit_Number_Type
) return Nat
;
423 function OA_Setting
(U
: Unit_Number_Type
) return Character;
424 function Source_Index
(U
: Unit_Number_Type
) return Source_File_Index
;
425 function Unit_File_Name
(U
: Unit_Number_Type
) return File_Name_Type
;
426 function Unit_Name
(U
: Unit_Number_Type
) return Unit_Name_Type
;
427 -- Get value of named field from given units table entry
429 procedure Set_Cunit
(U
: Unit_Number_Type
; N
: Node_Id
);
430 procedure Set_Cunit_Entity
(U
: Unit_Number_Type
; E
: Entity_Id
);
431 procedure Set_Dynamic_Elab
(U
: Unit_Number_Type
; B
: Boolean := True);
432 procedure Set_Error_Location
(U
: Unit_Number_Type
; W
: Source_Ptr
);
433 procedure Set_Fatal_Error
(U
: Unit_Number_Type
; B
: Boolean := True);
434 procedure Set_Generate_Code
(U
: Unit_Number_Type
; B
: Boolean := True);
435 procedure Set_Has_RACW
(U
: Unit_Number_Type
; B
: Boolean := True);
436 procedure Set_Has_Allocator
(U
: Unit_Number_Type
; B
: Boolean := True);
437 procedure Set_Is_Compiler_Unit
(U
: Unit_Number_Type
; B
: Boolean := True);
438 procedure Set_Ident_String
(U
: Unit_Number_Type
; N
: Node_Id
);
439 procedure Set_Loading
(U
: Unit_Number_Type
; B
: Boolean := True);
440 procedure Set_Main_CPU
(U
: Unit_Number_Type
; P
: Int
);
441 procedure Set_Main_Priority
(U
: Unit_Number_Type
; P
: Int
);
442 procedure Set_OA_Setting
(U
: Unit_Number_Type
; C
: Character);
443 procedure Set_Unit_Name
(U
: Unit_Number_Type
; N
: Unit_Name_Type
);
444 -- Set value of named field for given units table entry. Note that we
445 -- do not have an entry for each possible field, since some of the fields
446 -- can only be set by specialized interfaces (defined below).
448 function Version_Get
(U
: Unit_Number_Type
) return Word_Hex_String
;
449 -- Returns the version as a string with 8 hex digits (upper case letters)
451 function Last_Unit
return Unit_Number_Type
;
452 -- Unit number of last allocated unit
454 function Num_Units
return Nat
;
455 -- Number of units currently in unit table
457 procedure Remove_Unit
(U
: Unit_Number_Type
);
458 -- Remove unit U from unit table. Currently this is effective only
459 -- if U is the last unit currently stored in the unit table.
461 function Entity_Is_In_Main_Unit
(E
: Entity_Id
) return Boolean;
462 -- Returns True if the entity E is declared in the main unit, or, in
463 -- its corresponding spec, or one of its subunits. Entities declared
464 -- within generic instantiations return True if the instantiation is
465 -- itself "in the main unit" by this definition. Otherwise False.
467 function Get_Source_Unit
(N
: Node_Or_Entity_Id
) return Unit_Number_Type
;
468 pragma Inline
(Get_Source_Unit
);
469 function Get_Source_Unit
(S
: Source_Ptr
) return Unit_Number_Type
;
470 -- Return unit number of file identified by given source pointer value.
471 -- This call must always succeed, since any valid source pointer value
472 -- belongs to some previously loaded module. If the given source pointer
473 -- value is within an instantiation, this function returns the unit number
474 -- of the template, i.e. the unit containing the source code corresponding
475 -- to the given Source_Ptr value. The version taking a Node_Id argument, N,
476 -- simply applies the function to Sloc (N).
478 function Get_Code_Unit
(N
: Node_Or_Entity_Id
) return Unit_Number_Type
;
479 pragma Inline
(Get_Code_Unit
);
480 function Get_Code_Unit
(S
: Source_Ptr
) return Unit_Number_Type
;
481 -- This is like Get_Source_Unit, except that in the instantiation case,
482 -- it uses the location of the top level instantiation, rather than the
483 -- template, so it returns the unit number containing the code that
484 -- corresponds to the node N, or the source location S.
486 function In_Same_Source_Unit
(N1
, N2
: Node_Or_Entity_Id
) return Boolean;
487 pragma Inline
(In_Same_Source_Unit
);
488 -- Determines if the two nodes or entities N1 and N2 are in the same
489 -- source unit, the criterion being that Get_Source_Unit yields the
490 -- same value for each argument.
492 function In_Same_Code_Unit
(N1
, N2
: Node_Or_Entity_Id
) return Boolean;
493 pragma Inline
(In_Same_Code_Unit
);
494 -- Determines if the two nodes or entities N1 and N2 are in the same
495 -- code unit, the criterion being that Get_Code_Unit yields the same
496 -- value for each argument.
498 function In_Same_Extended_Unit
(N1
, N2
: Node_Or_Entity_Id
) return Boolean;
499 pragma Inline
(In_Same_Extended_Unit
);
500 -- Determines if two nodes or entities N1 and N2 are in the same
501 -- extended unit, where an extended unit is defined as a unit and all
502 -- its subunits (considered recursively, i.e. subunits of subunits are
503 -- included). Returns true if S1 and S2 are in the same extended unit
504 -- and False otherwise.
506 function In_Same_Extended_Unit
(S1
, S2
: Source_Ptr
) return Boolean;
507 pragma Inline
(In_Same_Extended_Unit
);
508 -- Determines if the two source locations S1 and S2 are in the same
509 -- extended unit, where an extended unit is defined as a unit and all
510 -- its subunits (considered recursively, i.e. subunits of subunits are
511 -- included). Returns true if S1 and S2 are in the same extended unit
512 -- and False otherwise.
514 function In_Extended_Main_Code_Unit
515 (N
: Node_Or_Entity_Id
) return Boolean;
516 -- Return True if the node is in the generated code of the extended main
517 -- unit, defined as the main unit, its specification (if any), and all
518 -- its subunits (considered recursively). Units for which this enquiry
519 -- returns True are those for which code will be generated. Nodes from
520 -- instantiations are included in the extended main unit for this call.
521 -- If the main unit is itself a subunit, then the extended main code unit
522 -- includes its parent unit, and the parent unit spec if it is separate.
524 function In_Extended_Main_Code_Unit
(Loc
: Source_Ptr
) return Boolean;
525 -- Same function as above, but argument is a source pointer rather
528 function In_Extended_Main_Source_Unit
529 (N
: Node_Or_Entity_Id
) return Boolean;
530 -- Return True if the node is in the source text of the extended main
531 -- unit, defined as the main unit, its specification (if any), and all
532 -- its subunits (considered recursively). Units for which this enquiry
533 -- returns True are those for which code will be generated. This differs
534 -- from In_Extended_Main_Code_Unit only in that instantiations are not
535 -- included for the purposes of this call. If the main unit is itself
536 -- a subunit, then the extended main source unit includes its parent unit,
537 -- and the parent unit spec if it is separate.
539 function In_Extended_Main_Source_Unit
(Loc
: Source_Ptr
) return Boolean;
540 -- Same function as above, but argument is a source pointer
542 function In_Predefined_Unit
(N
: Node_Or_Entity_Id
) return Boolean;
543 -- Returns True if the given node or entity appears within the source text
544 -- of a predefined unit (i.e. within Ada, Interfaces, System or within one
545 -- of the descendent packages of one of these three packages).
547 function In_Predefined_Unit
(S
: Source_Ptr
) return Boolean;
548 -- Same function as above but argument is a source pointer
550 function Earlier_In_Extended_Unit
(S1
, S2
: Source_Ptr
) return Boolean;
551 -- Given two Sloc values for which In_Same_Extended_Unit is true, determine
552 -- if S1 appears before S2. Returns True if S1 appears before S2, and False
553 -- otherwise. The result is undefined if S1 and S2 are not in the same
554 -- extended unit. Note: this routine will not give reliable results if
555 -- called after Sprint has been called with -gnatD set.
557 function Exact_Source_Name
(Loc
: Source_Ptr
) return String;
558 -- Return name of entity at location Loc exactly as written in the source.
559 -- this includes copying the wide character encodings exactly as they were
560 -- used in the source, so the caller must be aware of the possibility of
563 function Compilation_Switches_Last
return Nat
;
564 -- Return the count of stored compilation switches
566 function Get_Compilation_Switch
(N
: Pos
) return String_Ptr
;
567 -- Return the Nth stored compilation switch, or null if less than N
568 -- switches have been stored. Used by ASIS and back ends written in Ada.
570 function Get_Cunit_Unit_Number
(N
: Node_Id
) return Unit_Number_Type
;
571 -- Return unit number of the unit whose N_Compilation_Unit node is the
572 -- one passed as an argument. This must always succeed since the node
573 -- could not have been built without making a unit table entry.
575 function Get_Cunit_Entity_Unit_Number
576 (E
: Entity_Id
) return Unit_Number_Type
;
577 -- Return unit number of the unit whose compilation unit spec entity is
578 -- the one passed as an argument. This must always succeed since the
579 -- entity could not have been built without making a unit table entry.
581 function Increment_Serial_Number
return Nat
;
582 -- Increment Serial_Number field for current unit, and return the
583 -- incremented value.
585 procedure Synchronize_Serial_Number
;
586 -- This function increments the Serial_Number field for the current unit
587 -- but does not return the incremented value. This is used when there
588 -- is a situation where one path of control increments a serial number
589 -- (using Increment_Serial_Number), and the other path does not and it is
590 -- important to keep the serial numbers synchronized in the two cases (e.g.
591 -- when the references in a package and a client must be kept consistent).
593 procedure Replace_Linker_Option_String
595 Match_String
: String);
596 -- Replace an existing Linker_Option if the prefix Match_String matches,
597 -- otherwise call Store_Linker_Option_String.
599 procedure Store_Compilation_Switch
(Switch
: String);
600 -- Called to register a compilation switch, either front-end or back-end,
601 -- which may influence the generated output file(s). Switch is the text of
602 -- the switch to store (except that -fRTS gets changed back to --RTS).
604 procedure Enable_Switch_Storing
;
605 -- Enable registration of switches by Store_Compilation_Switch. Used to
606 -- avoid registering switches added automatically by the gcc driver at the
607 -- beginning of the command line.
609 procedure Disable_Switch_Storing
;
610 -- Disable registration of switches by Store_Compilation_Switch. Used to
611 -- avoid registering switches added automatically by the gcc driver at the
612 -- end of the command line.
614 procedure Store_Linker_Option_String
(S
: String_Id
);
615 -- This procedure is called to register the string from a pragma
616 -- Linker_Option. The argument is the Id of the string to register.
618 procedure Store_Note
(N
: Node_Id
);
619 -- This procedure is called to register a pragma N for which a notes
620 -- entry is required.
622 procedure Initialize
;
623 -- Initialize internal tables
626 -- Lock internal tables before calling back end
629 -- Unlock internal tables, in cases where the back end needs to modify them
632 -- Initializes internal tables from current tree file using the relevant
633 -- Table.Tree_Read routines.
635 procedure Tree_Write
;
636 -- Writes out internal tables to current tree file using the relevant
637 -- Table.Tree_Write routines.
639 function Is_Loaded
(Uname
: Unit_Name_Type
) return Boolean;
640 -- Determines if unit with given name is already loaded, i.e. there is
641 -- already an entry in the file table with this unit name for which the
642 -- corresponding file was found and parsed. Note that the Fatal_Error flag
643 -- of this entry must be checked before proceeding with further processing.
645 procedure Version_Referenced
(S
: String_Id
);
646 -- This routine is called from Exp_Attr to register the use of a Version
647 -- or Body_Version attribute. The argument is the external name used to
648 -- access the version string.
650 procedure List
(File_Names_Only
: Boolean := False);
651 -- Lists units in active library (i.e. generates output consisting of a
652 -- sorted listing of the units represented in File table, except for the
653 -- main unit). If File_Names_Only is set to True, then the list includes
654 -- only file names, and no other information. Otherwise the unit name and
655 -- time stamp are also output. File_Names_Only also restricts the list to
656 -- exclude any predefined files.
658 function Generic_May_Lack_ALI
(Sfile
: File_Name_Type
) return Boolean;
659 -- Generic units must be separately compiled. Since we always use
660 -- macro substitution for generics, the resulting object file is a dummy
661 -- one with no code, but the ALI file has the normal form, and we need
662 -- this ALI file so that the binder can work out a correct order of
665 -- However, ancient versions of GNAT used to not generate code or ALI
666 -- files for generic units, and this would yield complex order of
667 -- elaboration issues. These were fixed in GNAT 3.10. The support for not
668 -- compiling language-defined library generics was retained nonetheless
669 -- to facilitate bootstrap. Specifically, it is convenient to have
670 -- the same list of files to be compiled for all stages. So, if the
671 -- bootstrap compiler does not generate code for a given file, then
672 -- the stage1 compiler (and binder) also must deal with the case of
673 -- that file not being compiled. The predicate Generic_May_Lack_ALI is
674 -- True for those generic units for which missing ALI files are allowed.
676 procedure Write_Unit_Info
677 (Unit_Num
: Unit_Number_Type
;
679 Prefix
: String := "";
680 Withs
: Boolean := False);
681 -- Print out debugging information about the unit. Prefix precedes the rest
682 -- of the printout. If Withs is True, we print out units with'ed by this
683 -- unit (not counting limited withs).
686 pragma Inline
(Cunit
);
687 pragma Inline
(Cunit_Entity
);
688 pragma Inline
(Dependency_Num
);
689 pragma Inline
(Fatal_Error
);
690 pragma Inline
(Generate_Code
);
691 pragma Inline
(Has_Allocator
);
692 pragma Inline
(Has_RACW
);
693 pragma Inline
(Is_Compiler_Unit
);
694 pragma Inline
(Increment_Serial_Number
);
695 pragma Inline
(Loading
);
696 pragma Inline
(Main_CPU
);
697 pragma Inline
(Main_Priority
);
698 pragma Inline
(Munit_Index
);
699 pragma Inline
(OA_Setting
);
700 pragma Inline
(Set_Cunit
);
701 pragma Inline
(Set_Cunit_Entity
);
702 pragma Inline
(Set_Fatal_Error
);
703 pragma Inline
(Set_Generate_Code
);
704 pragma Inline
(Set_Has_Allocator
);
705 pragma Inline
(Set_Has_RACW
);
706 pragma Inline
(Set_Loading
);
707 pragma Inline
(Set_Main_CPU
);
708 pragma Inline
(Set_Main_Priority
);
709 pragma Inline
(Set_OA_Setting
);
710 pragma Inline
(Set_Unit_Name
);
711 pragma Inline
(Source_Index
);
712 pragma Inline
(Unit_File_Name
);
713 pragma Inline
(Unit_Name
);
715 type Unit_Record
is record
716 Unit_File_Name
: File_Name_Type
;
717 Unit_Name
: Unit_Name_Type
;
719 Expected_Unit
: Unit_Name_Type
;
720 Source_Index
: Source_File_Index
;
722 Cunit_Entity
: Entity_Id
;
723 Dependency_Num
: Int
;
724 Ident_String
: Node_Id
;
729 Error_Location
: Source_Ptr
;
730 Fatal_Error
: Boolean;
731 Generate_Code
: Boolean;
733 Is_Compiler_Unit
: Boolean;
734 Dynamic_Elab
: Boolean;
736 Has_Allocator
: Boolean;
737 OA_Setting
: Character;
740 -- The following representation clause ensures that the above record
741 -- has no holes. We do this so that when instances of this record are
742 -- written by Tree_Gen, we do not write uninitialized values to the file.
744 for Unit_Record
use record
745 Unit_File_Name
at 0 range 0 .. 31;
746 Unit_Name
at 4 range 0 .. 31;
747 Munit_Index
at 8 range 0 .. 31;
748 Expected_Unit
at 12 range 0 .. 31;
749 Source_Index
at 16 range 0 .. 31;
750 Cunit
at 20 range 0 .. 31;
751 Cunit_Entity
at 24 range 0 .. 31;
752 Dependency_Num
at 28 range 0 .. 31;
753 Ident_String
at 32 range 0 .. 31;
754 Main_Priority
at 36 range 0 .. 31;
755 Main_CPU
at 40 range 0 .. 31;
756 Serial_Number
at 44 range 0 .. 31;
757 Version
at 48 range 0 .. 31;
758 Error_Location
at 52 range 0 .. 31;
759 Fatal_Error
at 56 range 0 .. 7;
760 Generate_Code
at 57 range 0 .. 7;
761 Has_RACW
at 58 range 0 .. 7;
762 Dynamic_Elab
at 59 range 0 .. 7;
763 Is_Compiler_Unit
at 60 range 0 .. 7;
764 OA_Setting
at 61 range 0 .. 7;
765 Loading
at 62 range 0 .. 7;
766 Has_Allocator
at 63 range 0 .. 7;
769 for Unit_Record
'Size use 64 * 8;
770 -- This ensures that we did not leave out any fields
772 package Units
is new Table
.Table
(
773 Table_Component_Type
=> Unit_Record
,
774 Table_Index_Type
=> Unit_Number_Type
,
775 Table_Low_Bound
=> Main_Unit
,
776 Table_Initial
=> Alloc
.Units_Initial
,
777 Table_Increment
=> Alloc
.Units_Increment
,
778 Table_Name
=> "Units");
780 -- The following table stores strings from pragma Linker_Option lines
782 type Linker_Option_Entry
is record
784 -- The string for the linker option line
786 Unit
: Unit_Number_Type
;
787 -- The unit from which the linker option comes
790 package Linker_Option_Lines
is new Table
.Table
(
791 Table_Component_Type
=> Linker_Option_Entry
,
792 Table_Index_Type
=> Integer,
793 Table_Low_Bound
=> 1,
794 Table_Initial
=> Alloc
.Linker_Option_Lines_Initial
,
795 Table_Increment
=> Alloc
.Linker_Option_Lines_Increment
,
796 Table_Name
=> "Linker_Option_Lines");
798 -- The following table stores references to pragmas that generate Notes
800 type Notes_Entry
is record
801 Pragma_Node
: Node_Id
;
802 Unit
: Unit_Number_Type
;
805 package Notes
is new Table
.Table
(
806 Table_Component_Type
=> Notes_Entry
,
807 Table_Index_Type
=> Integer,
808 Table_Low_Bound
=> 1,
809 Table_Initial
=> Alloc
.Notes_Initial
,
810 Table_Increment
=> Alloc
.Notes_Increment
,
811 Table_Name
=> "Notes");
813 -- The following table records the compilation switches used to compile
814 -- the main unit. The table includes only switches. It excludes -o
815 -- switches as well as artifacts of the gcc/gnat1 interface such as
816 -- -quiet, -dumpbase, or -auxbase.
818 -- This table is set as part of the compiler argument scanning in
819 -- Back_End. It can also be reset in -gnatc mode from the data in an
820 -- existing ali file, and is read and written by the Tree_Read and
821 -- Tree_Write routines for ASIS.
823 package Compilation_Switches
is new Table
.Table
(
824 Table_Component_Type
=> String_Ptr
,
825 Table_Index_Type
=> Nat
,
826 Table_Low_Bound
=> 1,
828 Table_Increment
=> 100,
829 Table_Name
=> "Compilation_Switches");
831 Load_Msg_Sloc
: Source_Ptr
;
832 -- Location for placing error messages (a token in the main source text)
833 -- This is set from Sloc (Enode) by Load only in the case where this Sloc
834 -- is in the main source file. This ensures that not found messages and
835 -- circular dependency messages reference the original with in this source.
837 type Load_Stack_Entry
is record
838 Unit_Number
: Unit_Number_Type
;
842 -- The Load_Stack table contains a list of unit numbers (indexes into the
843 -- unit table) of units being loaded on a single dependency chain, and a
844 -- flag to indicate whether this unit is loaded through a limited_with
845 -- clause. The First entry is the main unit. The second entry, if present
846 -- is a unit on which the first unit depends, etc. This stack is used to
847 -- generate error messages showing the dependency chain if a file is not
848 -- found, or whether a true circular dependency exists. The Load_Unit
849 -- function makes an entry in this table when it is called, and removes
850 -- the entry just before it returns.
852 package Load_Stack
is new Table
.Table
(
853 Table_Component_Type
=> Load_Stack_Entry
,
854 Table_Index_Type
=> Int
,
855 Table_Low_Bound
=> 0,
856 Table_Initial
=> Alloc
.Load_Stack_Initial
,
857 Table_Increment
=> Alloc
.Load_Stack_Increment
,
858 Table_Name
=> "Load_Stack");
860 procedure Sort
(Tbl
: in out Unit_Ref_Table
);
861 -- This procedure sorts the given unit reference table in order of
862 -- ascending unit names, where the ordering relation is as described
863 -- by the comparison routines provided by package Uname.
865 -- The Version_Ref table records Body_Version and Version attribute
866 -- references. The entries are simply the strings for the external
867 -- names that correspond to the referenced values.
869 package Version_Ref
is new Table
.Table
(
870 Table_Component_Type
=> String_Id
,
871 Table_Index_Type
=> Nat
,
872 Table_Low_Bound
=> 1,
874 Table_Increment
=> 100,
875 Table_Name
=> "Version_Ref");