------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- L I B -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2020, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package contains routines for accessing and outputting the library -- information. It contains the routine to load subsidiary units. with Alloc; with Namet; use Namet; with Table; with Types; use Types; with GNAT.HTable; package Lib is type Unit_Ref_Table is array (Pos range <>) of Unit_Number_Type; -- Type to hold list of indirect references to unit number table type Compiler_State_Type is (Parsing, Analyzing); Compiler_State : Compiler_State_Type; -- Indicates current state of compilation. This is used to implement the -- function In_Extended_Main_Source_Unit. Parsing_Main_Extended_Source : Boolean := False; -- Set True if we are currently parsing a file that is part of the main -- extended source (the main unit, its spec, or one of its subunits). This -- flag to implement In_Extended_Main_Source_Unit. Analysing_Subunit_Of_Main : Boolean := False; -- Set to True when analyzing a subunit of the main source. When True, if -- the subunit is preprocessed and -gnateG is specified, then the -- preprocessed file (.prep) is written. -------------------------------------------- -- General Approach to Library Management -- -------------------------------------------- -- As described in GNote #1, when a unit is compiled, all its subsidiary -- units are recompiled, including the following: -- (a) Corresponding spec for a body -- (b) Parent spec of a child library spec -- (c) With'ed specs -- (d) Parent body of a subunit -- (e) Subunits corresponding to any specified stubs -- (f) Bodies of inlined subprograms that are called -- (g) Bodies of generic subprograms or packages that are instantiated -- (h) Bodies of packages containing either of the above two items -- (i) Specs and bodies of runtime units -- (j) Parent specs for with'ed child library units -- If a unit is being compiled only for syntax checking, then no subsidiary -- units are loaded, the syntax check applies only to the main unit, -- i.e. the one contained in the source submitted to the library. -- If a unit is being compiled for syntax and semantic checking, then only -- cases (a)-(d) loads are performed, since the full semantic checking can -- be carried out without needing (e)-(i) loads. In this case no object -- file, or library information file, is generated, so the missing units -- do not affect the results. -- Specifications of library subprograms, subunits, and generic specs -- and bodies, can only be compiled in syntax/semantic checking mode, -- since no code is ever generated directly for these units. In the case -- of subunits, only the compilation of the ultimate parent unit generates -- actual code. If a subunit is submitted to the compiler in syntax/ -- semantic checking mode, the parent (or parents in the nested case) are -- semantically checked only up to the point of the corresponding stub. -- If code is being generated, then all the above units are required, -- although the need for bodies of inlined procedures can be suppressed -- by the use of a switch that sets the mode to ignore pragma Inline -- statements. -- The two main sections of the front end, Par and Sem, are recursive. -- Compilation proceeds unit by unit making recursive calls as necessary. -- The process is controlled from the GNAT main program, which makes calls -- to Par and Sem sequence for the main unit. -- Par parses the given unit, and then, after the parse is complete, uses -- the Par.Load subprogram to load all its subsidiary units in categories -- (a)-(d) above, installing pointers to the loaded units in the parse -- tree, as described in a later section of this spec. If any of these -- required units is missing, a fatal error is signalled, so that no -- attempt is made to run Sem in such cases, since it is assumed that -- too many cascaded errors would result, and the confusion would not -- be helpful. -- Following the call to Par on the main unit, the entire tree of required -- units is thus loaded, and Sem is called on the main unit. The parameter -- passed to Sem is the unit to be analyzed. The visibility table, which -- is a single global structure, starts out containing only the entries -- for the visible entities in Standard. Every call to Sem establishes a -- new scope stack table, pushing an entry for Standard on entry to provide -- the proper initial scope environment. -- Sem first proceeds to perform semantic analysis on the currently loaded -- units as follows: -- In the case of a body (case (a) above), Sem analyzes the corresponding -- spec, using a recursive call to Sem. As is always expected to be the -- case with calls to Sem, any entities installed in the visibility table -- are removed on exit from Sem, so that these entities have to be -- reinstalled on return to continue the analysis of the body which of -- course needs visibility of these entities. -- -- In the case of the parent of a child spec (case (b) above), a similar -- call is made to Sem to analyze the parent. Again, on return, the -- entities from the analyzed parent spec have to be installed in the -- visibility table of the caller (the child unit), which must have -- visibility to the entities in its parent spec. -- For with'ed specs (case (c) above), a recursive call to Sem is made -- to analyze each spec in turn. After all the spec's have been analyzed, -- but not till that point, the entities from all the with'ed units are -- reinstalled in the visibility table so that the caller can proceed -- with the analysis of the unit doing the with's with the necessary -- entities made either potentially use visible or visible by selection -- as needed. -- Case (d) arises when Sem is passed a subunit to analyze. This means -- that the main unit is a subunit, and the unit passed to Sem is either -- the main unit, or one of its ancestors that is still a subunit. Since -- analysis must start at the top of the tree, Sem essentially cancels -- the current call by immediately making a call to analyze the parent -- (when this call is finished it immediately returns, so logically this -- call is like a goto). The subunit will then be analyzed at the proper -- time as described for the stub case. Note that we also turn off the -- indication that code should be generated in this case, since the only -- time we generate code for subunits is when compiling the main parent. -- Case (e), subunits corresponding to stubs, are handled as the stubs -- are encountered. There are three sub-cases: -- If the subunit has already been loaded, then this means that the -- main unit was a subunit, and we are back on our way down to it -- after following the initial processing described for case (d). -- In this case we analyze this particular subunit, as described -- for the case where we are generating code, but when we get back -- we are all done, since the rest of the parent is irrelevant. To -- get out of the parent, we raise the exception Subunit_Found, which -- is handled at the outer level of Sem. -- The cases where the subunit has not already been loaded correspond -- to cases where the main unit was a parent. In this case the action -- depends on whether or not we are generating code. If we are not -- generating code, then this is the case where we can simply ignore -- the subunit, since in checking mode we don't even want to insist -- that the subunit exist, much less waste time checking it. -- If we are generating code, then we need to load and analyze -- all subunits. This is achieved with a call to Lib.Load to load -- and parse the unit, followed by processing that installs the -- context clause of the subunit, analyzes the subunit, and then -- removes the context clause (from the visibility chains of the -- parent). Note that we do *not* do a recursive call to Sem in -- this case, precisely because we need to do the analysis of the -- subunit with the current visibility table and scope stack. -- Case (f) applies only to subprograms for which a pragma Inline is -- given, providing that the compiler is operating in the mode where -- pragma Inline's are activated. When the expander encounters a call -- to such a subprogram, it loads the body of the subprogram if it has -- not already been loaded, and calls Sem to process it. -- Case (g) is similar to case (f), except that the body of a generic -- is unconditionally required, regardless of compiler mode settings. -- As in the subprogram case, when the expander encounters a generic -- instantiation, it loads the generic body of the subprogram if it -- has not already been loaded, and calls Sem to process it. -- Case (h) arises when a package contains either an inlined subprogram -- which is called, or a generic which is instantiated. In this case the -- body of the package must be loaded and analyzed with a call to Sem. -- Case (i) is handled by adding implicit with clauses to the context -- clauses of all units that potentially reference the relevant runtime -- entities. Note that since we have the full set of units available, -- the parser can always determine the set of runtime units that is -- needed. These with clauses do not have associated use clauses, so -- all references to the entities must be by selection. Once the with -- clauses have been added, subsequent processing is as for normal -- with clauses. -- Case (j) is also handled by adding appropriate implicit with clauses -- to any unit that withs a child unit. Again there is no use clause, -- and subsequent processing proceeds as for an explicit with clause. -- Sem thus completes the loading of all required units, except those -- required for inline subprogram bodies or inlined generics. If any -- of these load attempts fails, then the expander will not be called, -- even if code was to be generated. If the load attempts all succeed -- then the expander is called, though the attempt to generate code may -- still fail if an error occurs during a load attempt for an inlined -- body or a generic body. ------------------------------------------- -- Special Handling of Subprogram Bodies -- ------------------------------------------- -- A subprogram body (in an adb file) may stand for both a spec and a body. -- A simple model (and one that was adopted through version 2.07) is simply -- to assume that such an adb file acts as its own spec if no ads file is -- is present. -- However, this is not correct. RM 10.1.4(4) requires that such a body -- act as a spec unless a subprogram declaration of the same name is -- already present. The correct interpretation of this in GNAT library -- terms is to ignore an existing ads file of the same name unless this -- ads file contains a subprogram declaration with the same name. -- If there is an ads file with a unit other than a subprogram declaration -- with the same name, then a fatal message is output, noting that this -- irrelevant file must be deleted before the body can be compiled. See -- ACVC test CA1020D to see how this processing is required. ----------------- -- Global Data -- ----------------- Current_Sem_Unit : Unit_Number_Type := Main_Unit; -- Unit number of unit currently being analyzed/expanded. This is set when -- ever a new unit is entered, saving and restoring the old value, so that -- it always reflects the unit currently being analyzed. The initial value -- of Main_Unit ensures that a proper value is set initially, and in -- particular for analysis of configuration pragmas in gnat.adc. Main_Unit_Entity : Entity_Id; -- Entity of main unit, same as Cunit_Entity (Main_Unit) except where -- Main_Unit is a body with a separate spec, in which case it is the -- entity for the spec. ----------------- -- Units Table -- ----------------- -- The units table has an entry for each unit (source file) read in by the -- current compilation. The table is indexed by the unit number value. -- The first entry in the table, subscript Main_Unit, is for the main file. -- Each entry in this units table contains the following data. -- Cunit -- Pointer to the N_Compilation_Unit node. Initially set to Empty by -- Lib.Load, and then reset to the required node by the parser when -- the unit is parsed. -- Cunit_Entity -- Pointer to the entity node for the compilation unit. Initially set -- to Empty by Lib.Load, and then reset to the required entity by the -- parser when the unit is parsed. -- Dependency_Num -- This is the number of the unit within the generated dependency -- lines (D lines in the ALI file) which are sorted into alphabetical -- order. The number is ones origin, so a value of 2 refers to the -- second generated D line. The Dependency_Num values are set as the -- D lines are generated, and are used to generate proper unit -- references in the generated xref information and SCO output. -- Dynamic_Elab -- A flag indicating if this unit was compiled with dynamic elaboration -- checks specified (as the result of using the -gnatE compilation -- option or a pragma Elaboration_Checks (Dynamic)). -- Error_Location -- This is copied from the Sloc field of the Enode argument passed -- to Load_Unit. It refers to the enclosing construct which caused -- this unit to be loaded, e.g. most typically the with clause that -- referenced the unit, and is used for error handling in Par.Load. -- Expected_Unit -- This is the expected unit name for a file other than the main unit, -- since these are cases where we load the unit using Lib.Load and we -- know the unit that is expected. It must be the same as Unit_Name -- if it is set (see test in Par.Load). Expected_Unit is set to -- No_Name for the main unit. -- Fatal_Error -- A flag that is initialized to None and gets set to Error if a fatal -- error occurs during the processing of a unit. A fatal error is one -- defined as serious enough to stop the next phase of the compiler -- from running (i.e. fatal error during parsing stops semantics, -- fatal error during semantics stops code generation). Note that -- currently, errors of any kind cause Fatal_Error to be set, but -- eventually perhaps only errors labeled as fatal errors should be -- this severe if we decide to try Sem on sources with minor errors. -- There are three settings (see declaration of Fatal_Type). -- Generate_Code -- This flag is set True for all units in the current file for which -- code is to be generated. This includes the unit explicitly compiled, -- together with its specification, and any subunits. -- Has_RACW -- A Boolean flag, initially set to False when a unit entry is created, -- and set to True if the unit defines a remote access to class wide -- (RACW) object. This is used for controlling generation of the RA -- attribute in the ali file. -- Ident_String -- N_String_Literal node from a valid pragma Ident that applies to -- this unit. If no Ident pragma applies to the unit, then Empty. -- Is_Predefined_Renaming -- True if this unit is a predefined renaming, as in "Text_IO renames -- Ada.Text_IO"). -- Is_Internal_Unit -- Same as In_Predefined_Unit, except units in the GNAT hierarchy are -- included. -- Is_Predefined_Unit -- True if this unit is predefined (i.e. part of the Ada, System, or -- Interface hierarchies, or Is_Predefined_Renaming). Note that units -- in the GNAT hierarchy are not considered predefined. -- Loading -- A flag that is used to catch circular WITH dependencies. It is set -- True when an entry is initially created in the file table, and set -- False when the load is completed, or ends with an error. -- Main_Priority -- This field is used to indicate the priority of a possible main -- program, as set by a pragma Priority. A value of -1 indicates -- that the default priority is to be used (and is also used for -- entries that do not correspond to possible main programs). -- Main_CPU -- This field is used to indicate the affinity of a possible main -- program, as set by a pragma CPU. A value of -1 indicates -- that the default affinity is to be used (and is also used for -- entries that do not correspond to possible main programs). -- Munit_Index -- The index of the unit within the file for multiple unit per file -- mode. Set to zero in normal single unit per file mode. -- No_Elab_Code_All -- A flag set when a pragma or aspect No_Elaboration_Code_All applies -- to the unit. This is used to implement the transitive WITH rules -- (and for no other purpose). -- OA_Setting -- This is a character field containing L if Optimize_Alignment mode -- was set locally, and O/T/S for Off/Time/Space default if not. -- Primary_Stack_Count -- The number of primary stacks belonging to tasks defined within the -- unit that have no Storage_Size specified when the either restriction -- No_Implicit_Heap_Allocations or No_Implicit_Task_Allocations is -- active. Only used by the binder to generate stacks for these tasks -- at bind time. -- Sec_Stack_Count -- The number of secondary stacks belonging to tasks defined within the -- unit that have no Secondary_Stack_Size specified when the either -- the No_Implicit_Heap_Allocations or No_Implicit_Task_Allocations -- restrictions are active. Only used by the binder to generate stacks -- for these tasks at bind time. -- Serial_Number -- This field holds a serial number used by New_Internal_Name to -- generate unique temporary numbers on a unit by unit basis. The -- only access to this field is via the Increment_Serial_Number -- routine which increments the current value and returns it. This -- serial number is separate for each unit. -- Source_Index -- The index in the source file table of the corresponding source file. -- Set when the entry is created by a call to Lib.Load and then cannot -- be changed. -- Unit_File_Name -- The name of the source file containing the unit. Set when the entry -- is created by a call to Lib.Load, and then cannot be changed. -- Unit_Name -- The name of the unit. Initialized to No_Name by Lib.Load, and then -- set by the parser when the unit is parsed to the unit name actually -- found in the file (which should, in the absence of errors) be the -- same name as Expected_Unit. -- Version -- This field holds the version of the unit, which is computed as -- the exclusive or of the checksums of this unit, and all its -- semantically dependent units. Access to the version number field -- is not direct, but is done through the routines described below. -- When a unit table entry is created, this field is initialized to -- the checksum of the corresponding source file. Version_Update is -- then called to reflect the contributions of any unit on which this -- unit is semantically dependent. -- The units table is reset to empty at the start of the compilation of -- each main unit by Lib.Initialize. Entries are then added by calls to -- the Lib.Load procedure. The following subprograms are used to access -- and modify entries in the Units table. Individual entries are accessed -- using a unit number value which ranges from Main_Unit (the first entry, -- which is always for the current main unit) to Last_Unit. Default_Main_Priority : constant Int := -1; -- Value used in Main_Priority field to indicate default main priority Default_Main_CPU : constant Int := -1; -- Value used in Main_CPU field to indicate default main affinity -- The following defines settings for the Fatal_Error field type Fatal_Type is ( None, -- No error detected for this unit Error_Detected, -- Fatal error detected that prevents moving to the next phase. For -- example, a fatal error during parsing inhibits semantic analysis. Error_Ignored); -- A fatal error was detected, but we are in Try_Semantics mode (as set -- by -gnatq or -gnatQ). This does not stop the compiler from proceding, -- but tools can use this status (e.g. ASIS looking at the generated -- tree) to know that a fatal error was detected. function Cunit (U : Unit_Number_Type) return Node_Id; function Cunit_Entity (U : Unit_Number_Type) return Entity_Id; function Dependency_Num (U : Unit_Number_Type) return Nat; function Dynamic_Elab (U : Unit_Number_Type) return Boolean; function Error_Location (U : Unit_Number_Type) return Source_Ptr; function Expected_Unit (U : Unit_Number_Type) return Unit_Name_Type; function Fatal_Error (U : Unit_Number_Type) return Fatal_Type; function Generate_Code (U : Unit_Number_Type) return Boolean; function Ident_String (U : Unit_Number_Type) return Node_Id; function Has_RACW (U : Unit_Number_Type) return Boolean; function Is_Predefined_Renaming (U : Unit_Number_Type) return Boolean; function Is_Internal_Unit (U : Unit_Number_Type) return Boolean; function Is_Predefined_Unit (U : Unit_Number_Type) return Boolean; function Loading (U : Unit_Number_Type) return Boolean; function Main_CPU (U : Unit_Number_Type) return Int; function Main_Priority (U : Unit_Number_Type) return Int; function Munit_Index (U : Unit_Number_Type) return Nat; function No_Elab_Code_All (U : Unit_Number_Type) return Boolean; function OA_Setting (U : Unit_Number_Type) return Character; function Primary_Stack_Count (U : Unit_Number_Type) return Int; function Sec_Stack_Count (U : Unit_Number_Type) return Int; function Source_Index (U : Unit_Number_Type) return Source_File_Index; function Unit_File_Name (U : Unit_Number_Type) return File_Name_Type; function Unit_Name (U : Unit_Number_Type) return Unit_Name_Type; -- Get value of named field from given units table entry -- WARNING: There is a matching C declaration of a few subprograms in fe.h procedure Set_Cunit (U : Unit_Number_Type; N : Node_Id); procedure Set_Cunit_Entity (U : Unit_Number_Type; E : Entity_Id); procedure Set_Dynamic_Elab (U : Unit_Number_Type; B : Boolean := True); procedure Set_Error_Location (U : Unit_Number_Type; W : Source_Ptr); procedure Set_Fatal_Error (U : Unit_Number_Type; V : Fatal_Type); procedure Set_Generate_Code (U : Unit_Number_Type; B : Boolean := True); procedure Set_Has_RACW (U : Unit_Number_Type; B : Boolean := True); procedure Set_Ident_String (U : Unit_Number_Type; N : Node_Id); procedure Set_Loading (U : Unit_Number_Type; B : Boolean := True); procedure Set_Main_CPU (U : Unit_Number_Type; P : Int); procedure Set_No_Elab_Code_All (U : Unit_Number_Type; B : Boolean := True); procedure Set_Main_Priority (U : Unit_Number_Type; P : Int); procedure Set_OA_Setting (U : Unit_Number_Type; C : Character); procedure Set_Unit_Name (U : Unit_Number_Type; N : Unit_Name_Type); -- Set value of named field for given units table entry. Note that we -- do not have an entry for each possible field, since some of the fields -- can only be set by specialized interfaces (defined below). function Compilation_Switches_Last return Nat; -- Return the count of stored compilation switches procedure Disable_Switch_Storing; -- Disable registration of switches by Store_Compilation_Switch. Used to -- avoid registering switches added automatically by the gcc driver at the -- end of the command line. function Earlier_In_Extended_Unit (S1 : Source_Ptr; S2 : Source_Ptr) return Boolean; -- Given two Sloc values for which In_Same_Extended_Unit is true, determine -- if S1 appears before S2. Returns True if S1 appears before S2, and False -- otherwise. The result is undefined if S1 and S2 are not in the same -- extended unit. Note: this routine will not give reliable results if -- called after Sprint has been called with -gnatD set. function Earlier_In_Extended_Unit (N1 : Node_Or_Entity_Id; N2 : Node_Or_Entity_Id) return Boolean; -- Same as above, but the inputs denote nodes or entities procedure Enable_Switch_Storing; -- Enable registration of switches by Store_Compilation_Switch. Used to -- avoid registering switches added automatically by the gcc driver at the -- beginning of the command line. function Entity_Is_In_Main_Unit (E : Entity_Id) return Boolean; -- Returns True if the entity E is declared in the main unit, or, in -- its corresponding spec, or one of its subunits. Entities declared -- within generic instantiations return True if the instantiation is -- itself "in the main unit" by this definition. Otherwise False. function Exact_Source_Name (Loc : Source_Ptr) return String; -- Return name of entity at location Loc exactly as written in the source. -- This includes copying the wide character encodings exactly as they were -- used in the source, so the caller must be aware of the possibility of -- such encodings. function Get_Compilation_Switch (N : Pos) return String_Ptr; -- Return the Nth stored compilation switch, or null if less than N -- switches have been stored. Used by back ends written in Ada. function Generic_May_Lack_ALI (Unum : Unit_Number_Type) return Boolean; -- Generic units must be separately compiled. Since we always use -- macro substitution for generics, the resulting object file is a dummy -- one with no code, but the ALI file has the normal form, and we need -- this ALI file so that the binder can work out a correct order of -- elaboration. -- -- However, ancient versions of GNAT used to not generate code or ALI -- files for generic units, and this would yield complex order of -- elaboration issues. These were fixed in GNAT 3.10. The support for not -- compiling language-defined library generics was retained nonetheless -- to facilitate bootstrap. Specifically, it is convenient to have -- the same list of files to be compiled for all stages. So, if the -- bootstrap compiler does not generate code for a given file, then -- the stage1 compiler (and binder) also must deal with the case of -- that file not being compiled. The predicate Generic_May_Lack_ALI is -- True for those generic units for which missing ALI files are allowed. function Get_Cunit_Unit_Number (N : Node_Id) return Unit_Number_Type; -- Return unit number of the unit whose N_Compilation_Unit node is the -- one passed as an argument. This must always succeed since the node -- could not have been built without making a unit table entry. function Get_Cunit_Entity_Unit_Number (E : Entity_Id) return Unit_Number_Type; -- Return unit number of the unit whose compilation unit spec entity is -- the one passed as an argument. This must always succeed since the -- entity could not have been built without making a unit table entry. function Get_Source_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type; pragma Inline (Get_Source_Unit); function Get_Source_Unit (S : Source_Ptr) return Unit_Number_Type; -- Return unit number of file identified by given source pointer value. -- This call must always succeed, since any valid source pointer value -- belongs to some previously loaded module. If the given source pointer -- value is within an instantiation, this function returns the unit number -- of the template, i.e. the unit containing the source code corresponding -- to the given Source_Ptr value. The version taking a Node_Id argument, N, -- simply applies the function to Sloc (N). function Get_Code_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type; pragma Inline (Get_Code_Unit); function Get_Code_Unit (S : Source_Ptr) return Unit_Number_Type; -- This is like Get_Source_Unit, except that in the instantiation case, -- it uses the location of the top level instantiation, rather than the -- template, so it returns the unit number containing the code that -- corresponds to the node N, or the source location S. function Get_Top_Level_Code_Unit (N : Node_Or_Entity_Id) return Unit_Number_Type; pragma Inline (Get_Code_Unit); function Get_Top_Level_Code_Unit (S : Source_Ptr) return Unit_Number_Type; -- This is like Get_Code_Unit, except that in the case of subunits, it -- returns the top-level unit to which the subunit belongs instead of -- the subunit. -- -- Note: for nodes and slocs in declarations of library-level instances of -- generics these routines wrongly return the unit number corresponding to -- the body of the instance. In effect, locations of SPARK references in -- ALI files are bogus. However, fixing this is not worth the effort, since -- these references are only used for debugging. function In_Extended_Main_Code_Unit (N : Node_Or_Entity_Id) return Boolean; -- Return True if the node is in the generated code of the extended main -- unit, defined as the main unit, its specification (if any), and all -- its subunits (considered recursively). Units for which this enquiry -- returns True are those for which code will be generated. Nodes from -- instantiations are included in the extended main unit for this call. -- If the main unit is itself a subunit, then the extended main code unit -- includes its parent unit, and the parent unit spec if it is separate. -- -- This routine (and the following three routines) all return False if -- Sloc (N) is No_Location or Standard_Location. In an earlier version, -- they returned True for Standard_Location, but this was odd, and some -- archeology indicated that this was done for the sole benefit of the -- call in Restrict.Check_Restriction_No_Dependence, so we have moved -- the special case check to that routine. This avoids some difficulties -- with some other calls that malfunctioned with the odd return of True. -- WARNING: There is a matching C declaration of this subprogram in fe.h function In_Extended_Main_Code_Unit (Loc : Source_Ptr) return Boolean; -- Same function as above, but argument is a source pointer rather -- than a node. function In_Extended_Main_Source_Unit (N : Node_Or_Entity_Id) return Boolean; -- Return True if the node is in the source text of the extended main -- unit, defined as the main unit, its specification (if any), and all -- its subunits (considered recursively). Units for which this enquiry -- returns True are those for which code will be generated. This differs -- from In_Extended_Main_Code_Unit only in that instantiations are not -- included for the purposes of this call. If the main unit is itself -- a subunit, then the extended main source unit includes its parent unit, -- and the parent unit spec if it is separate. function In_Extended_Main_Source_Unit (Loc : Source_Ptr) return Boolean; -- Same function as above, but argument is a source pointer function In_Predefined_Unit (N : Node_Or_Entity_Id) return Boolean; -- Returns True if the given node or entity appears within the source text -- of a predefined unit (i.e. within Ada, Interfaces, System or within one -- of the descendant packages of one of these three packages). function In_Predefined_Unit (S : Source_Ptr) return Boolean; pragma Inline (In_Predefined_Unit); -- Same function as above but argument is a source pointer function In_Internal_Unit (N : Node_Or_Entity_Id) return Boolean; function In_Internal_Unit (S : Source_Ptr) return Boolean; pragma Inline (In_Internal_Unit); -- Same as In_Predefined_Unit, except units in the GNAT hierarchy are -- included. function In_Predefined_Renaming (N : Node_Or_Entity_Id) return Boolean; function In_Predefined_Renaming (S : Source_Ptr) return Boolean; pragma Inline (In_Predefined_Renaming); -- Returns True if N or S is in a predefined renaming unit function In_Same_Code_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean; pragma Inline (In_Same_Code_Unit); -- Determines if the two nodes or entities N1 and N2 are in the same -- code unit, the criterion being that Get_Code_Unit yields the same -- value for each argument. function In_Same_Extended_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean; pragma Inline (In_Same_Extended_Unit); -- Determines if two nodes or entities N1 and N2 are in the same -- extended unit, where an extended unit is defined as a unit and all -- its subunits (considered recursively, i.e. subunits of subunits are -- included). Returns true if S1 and S2 are in the same extended unit -- and False otherwise. function In_Same_Extended_Unit (S1, S2 : Source_Ptr) return Boolean; pragma Inline (In_Same_Extended_Unit); -- Determines if the two source locations S1 and S2 are in the same -- extended unit, where an extended unit is defined as a unit and all -- its subunits (considered recursively, i.e. subunits of subunits are -- included). Returns true if S1 and S2 are in the same extended unit -- and False otherwise. function In_Same_Source_Unit (N1, N2 : Node_Or_Entity_Id) return Boolean; pragma Inline (In_Same_Source_Unit); -- Determines if the two nodes or entities N1 and N2 are in the same -- source unit, the criterion being that Get_Source_Unit yields the -- same value for each argument. procedure Increment_Primary_Stack_Count (Increment : Int); -- Increment the Primary_Stack_Count field for the current unit by -- Increment. procedure Increment_Sec_Stack_Count (Increment : Int); -- Increment the Sec_Stack_Count field for the current unit by Increment function Increment_Serial_Number return Nat; -- Increment Serial_Number field for current unit, and return the -- incremented value. procedure Initialize; -- Initialize internal tables function Is_Loaded (Uname : Unit_Name_Type) return Boolean; -- Determines if unit with given name is already loaded, i.e. there is -- already an entry in the file table with this unit name for which the -- corresponding file was found and parsed. Note that the Fatal_Error value -- of this entry must be checked before proceeding with further processing. function Last_Unit return Unit_Number_Type; -- Unit number of last allocated unit procedure List (File_Names_Only : Boolean := False); -- Lists units in active library (i.e. generates output consisting of a -- sorted listing of the units represented in File table, except for the -- main unit). If File_Names_Only is set to True, then the list includes -- only file names, and no other information. Otherwise the unit name and -- time stamp are also output. File_Names_Only also restricts the list to -- exclude any predefined files. procedure Lock; -- Lock internal tables before calling back end function Num_Units return Nat; -- Number of units currently in unit table procedure Remove_Unit (U : Unit_Number_Type); -- Remove unit U from unit table. Currently this is effective only if U is -- the last unit currently stored in the unit table. procedure Replace_Linker_Option_String (S : String_Id; Match_String : String); -- Replace an existing Linker_Option if the prefix Match_String matches, -- otherwise call Store_Linker_Option_String. procedure Store_Compilation_Switch (Switch : String); -- Called to register a compilation switch, either front-end or back-end, -- which may influence the generated output file(s). Switch is the text of -- the switch to store (except that -fRTS gets changed back to --RTS). procedure Store_Linker_Option_String (S : String_Id); -- This procedure is called to register the string from a pragma -- Linker_Option. The argument is the Id of the string to register. procedure Store_Note (N : Node_Id); -- This procedure is called to register a pragma N for which a notes -- entry is required. procedure Synchronize_Serial_Number; -- This function increments the Serial_Number field for the current unit -- but does not return the incremented value. This is used when there -- is a situation where one path of control increments a serial number -- (using Increment_Serial_Number), and the other path does not and it is -- important to keep the serial numbers synchronized in the two cases (e.g. -- when the references in a package and a client must be kept consistent). procedure Unlock; -- Unlock internal tables, in cases where the back end needs to modify them function Version_Get (U : Unit_Number_Type) return Word_Hex_String; -- Returns the version as a string with 8 hex digits (upper case letters) procedure Version_Referenced (S : String_Id); -- This routine is called from Exp_Attr to register the use of a Version -- or Body_Version attribute. The argument is the external name used to -- access the version string. procedure Write_Unit_Info (Unit_Num : Unit_Number_Type; Item : Node_Id; Prefix : String := ""; Withs : Boolean := False); -- Print out debugging information about the unit. Prefix precedes the rest -- of the printout. If Withs is True, we print out units with'ed by this -- unit (not counting limited withs). --------------------------------------------------------------- -- Special Handling for Restriction_Set (No_Dependence) Case -- --------------------------------------------------------------- -- If we have a Restriction_Set attribute for No_Dependence => unit, -- and the unit is not given in a No_Dependence restriction that we -- can see, the attribute will return False. -- We have to ensure in this case that the binder will reject any attempt -- to set a No_Dependence restriction in some other unit in the partition. -- If the unit is in the semantic closure, then of course it is properly -- WITH'ed by someone, and the binder will do this job automatically as -- part of its normal processing. -- But if the unit is not in the semantic closure, we must make sure the -- binder knows about it. The use of the Restriction_Set attribute giving -- a result of False does not mean of itself that we have to include the -- unit in the partition. So what we do is to generate a with (W) line in -- the ali file (with no file name information), but no corresponding D -- (dependency) line. This is recognized by the binder as meaning "Don't -- let anyone specify No_Dependence for this unit, but you don't have to -- include it if there is no real W line for the unit". -- The following table keeps track of relevant units. It is used in the -- Lib.Writ circuit for outputting With lines to output the special with -- line with RA if the unit is not in the semantic closure. package Restriction_Set_Dependences is new Table.Table ( Table_Component_Type => Unit_Name_Type, Table_Index_Type => Int, Table_Low_Bound => 0, Table_Initial => 10, Table_Increment => 100, Table_Name => "Restriction_Attribute_Dependences"); private pragma Inline (Cunit); pragma Inline (Cunit_Entity); pragma Inline (Dependency_Num); pragma Inline (Fatal_Error); pragma Inline (Generate_Code); pragma Inline (Has_RACW); pragma Inline (Increment_Primary_Stack_Count); pragma Inline (Increment_Sec_Stack_Count); pragma Inline (Increment_Serial_Number); pragma Inline (Is_Internal_Unit); pragma Inline (Is_Loaded); pragma Inline (Is_Predefined_Renaming); pragma Inline (Is_Predefined_Unit); pragma Inline (Loading); pragma Inline (Main_CPU); pragma Inline (Main_Priority); pragma Inline (Munit_Index); pragma Inline (No_Elab_Code_All); pragma Inline (OA_Setting); pragma Inline (Primary_Stack_Count); pragma Inline (Set_Cunit); pragma Inline (Set_Cunit_Entity); pragma Inline (Set_Fatal_Error); pragma Inline (Set_Generate_Code); pragma Inline (Set_Has_RACW); pragma Inline (Sec_Stack_Count); pragma Inline (Set_Loading); pragma Inline (Set_Main_CPU); pragma Inline (Set_Main_Priority); pragma Inline (Set_No_Elab_Code_All); pragma Inline (Set_OA_Setting); pragma Inline (Set_Unit_Name); pragma Inline (Source_Index); pragma Inline (Unit_File_Name); pragma Inline (Unit_Name); -- The Units Table type Unit_Record is record Unit_File_Name : File_Name_Type; Unit_Name : Unit_Name_Type; Munit_Index : Nat; Expected_Unit : Unit_Name_Type; Source_Index : Source_File_Index; Cunit : Node_Id; Cunit_Entity : Entity_Id; Dependency_Num : Int; Ident_String : Node_Id; Main_Priority : Int; Main_CPU : Int; Primary_Stack_Count : Int; Sec_Stack_Count : Int; Serial_Number : Nat; Version : Word; Error_Location : Source_Ptr; Fatal_Error : Fatal_Type; Generate_Code : Boolean; Has_RACW : Boolean; Dynamic_Elab : Boolean; No_Elab_Code_All : Boolean; Filler : Boolean; Loading : Boolean; OA_Setting : Character; Is_Predefined_Renaming : Boolean; Is_Internal_Unit : Boolean; Is_Predefined_Unit : Boolean; Filler2 : Boolean; end record; -- The following representation clause ensures that the above record -- has no holes. We do this so that when instances of this record are -- written by Tree_Gen, we do not write uninitialized values to the file. for Unit_Record use record Unit_File_Name at 0 range 0 .. 31; Unit_Name at 4 range 0 .. 31; Munit_Index at 8 range 0 .. 31; Expected_Unit at 12 range 0 .. 31; Source_Index at 16 range 0 .. 31; Cunit at 20 range 0 .. 31; Cunit_Entity at 24 range 0 .. 31; Dependency_Num at 28 range 0 .. 31; Ident_String at 32 range 0 .. 31; Main_Priority at 36 range 0 .. 31; Main_CPU at 40 range 0 .. 31; Primary_Stack_Count at 44 range 0 .. 31; Sec_Stack_Count at 48 range 0 .. 31; Serial_Number at 52 range 0 .. 31; Version at 56 range 0 .. 31; Error_Location at 60 range 0 .. 31; Fatal_Error at 64 range 0 .. 7; Generate_Code at 65 range 0 .. 7; Has_RACW at 66 range 0 .. 7; Dynamic_Elab at 67 range 0 .. 7; No_Elab_Code_All at 68 range 0 .. 7; Filler at 69 range 0 .. 7; OA_Setting at 70 range 0 .. 7; Loading at 71 range 0 .. 7; Is_Predefined_Renaming at 72 range 0 .. 7; Is_Internal_Unit at 73 range 0 .. 7; Is_Predefined_Unit at 74 range 0 .. 7; Filler2 at 75 range 0 .. 7; end record; for Unit_Record'Size use 76 * 8; -- This ensures that we did not leave out any fields package Units is new Table.Table ( Table_Component_Type => Unit_Record, Table_Index_Type => Unit_Number_Type, Table_Low_Bound => Main_Unit, Table_Initial => Alloc.Units_Initial, Table_Increment => Alloc.Units_Increment, Table_Name => "Units"); -- The following table records a mapping between a name and the entry in -- the units table whose Unit_Name is this name. It is used to speed up -- the Is_Loaded function, whose original implementation (linear search) -- could account for 2% of the time spent in the front end. Note that, in -- the case of source files containing multiple units, the units table may -- temporarily contain two entries with the same Unit_Name during parsing, -- which means that the mapping must be to the first entry in the table. Unit_Name_Table_Size : constant := 257; -- Number of headers in hash table subtype Unit_Name_Header_Num is Integer range 0 .. Unit_Name_Table_Size - 1; -- Range of headers in hash table function Unit_Name_Hash (Id : Unit_Name_Type) return Unit_Name_Header_Num; -- Simple hash function for Unit_Name_Types package Unit_Names is new GNAT.Htable.Simple_HTable (Header_Num => Unit_Name_Header_Num, Element => Unit_Number_Type, No_Element => No_Unit, Key => Unit_Name_Type, Hash => Unit_Name_Hash, Equal => "="); procedure Init_Unit_Name (U : Unit_Number_Type; N : Unit_Name_Type); pragma Inline (Init_Unit_Name); -- Both set the Unit_Name for the given units table entry and register a -- mapping between this name and the entry. -- The following table stores strings from pragma Linker_Option lines type Linker_Option_Entry is record Option : String_Id; -- The string for the linker option line Unit : Unit_Number_Type; -- The unit from which the linker option comes end record; package Linker_Option_Lines is new Table.Table ( Table_Component_Type => Linker_Option_Entry, Table_Index_Type => Integer, Table_Low_Bound => 1, Table_Initial => Alloc.Linker_Option_Lines_Initial, Table_Increment => Alloc.Linker_Option_Lines_Increment, Table_Name => "Linker_Option_Lines"); -- The following table stores references to pragmas that generate Notes package Notes is new Table.Table ( Table_Component_Type => Node_Id, Table_Index_Type => Integer, Table_Low_Bound => 1, Table_Initial => Alloc.Notes_Initial, Table_Increment => Alloc.Notes_Increment, Table_Name => "Notes"); -- The following table records the compilation switches used to compile -- the main unit. The table includes only switches. It excludes -o -- switches as well as artifacts of the gcc/gnat1 interface such as -- -quiet, or -dumpbase. -- This table is set as part of the compiler argument scanning in -- Back_End. It can also be reset in -gnatc mode from the data in an -- existing ali file. package Compilation_Switches is new Table.Table ( Table_Component_Type => String_Ptr, Table_Index_Type => Nat, Table_Low_Bound => 1, Table_Initial => 30, Table_Increment => 100, Table_Name => "Compilation_Switches"); Load_Msg_Sloc : Source_Ptr; -- Location for placing error messages (a token in the main source text) -- This is set from Sloc (Enode) by Load only in the case where this Sloc -- is in the main source file. This ensures that not found messages and -- circular dependency messages reference the original with in this source. type Load_Stack_Entry is record Unit_Number : Unit_Number_Type; With_Node : Node_Id; end record; -- The Load_Stack table contains a list of unit numbers (indexes into the -- unit table) of units being loaded on a single dependency chain, and a -- flag to indicate whether this unit is loaded through a limited_with -- clause. The First entry is the main unit. The second entry, if present -- is a unit on which the first unit depends, etc. This stack is used to -- generate error messages showing the dependency chain if a file is not -- found, or whether a true circular dependency exists. The Load_Unit -- function makes an entry in this table when it is called, and removes -- the entry just before it returns. package Load_Stack is new Table.Table ( Table_Component_Type => Load_Stack_Entry, Table_Index_Type => Int, Table_Low_Bound => 0, Table_Initial => Alloc.Load_Stack_Initial, Table_Increment => Alloc.Load_Stack_Increment, Table_Name => "Load_Stack"); procedure Sort (Tbl : in out Unit_Ref_Table); -- This procedure sorts the given unit reference table in order of -- ascending unit names, where the ordering relation is as described -- by the comparison routines provided by package Uname. -- The Version_Ref table records Body_Version and Version attribute -- references. The entries are simply the strings for the external -- names that correspond to the referenced values. package Version_Ref is new Table.Table ( Table_Component_Type => String_Id, Table_Index_Type => Nat, Table_Low_Bound => 1, Table_Initial => 20, Table_Increment => 100, Table_Name => "Version_Ref"); end Lib;