Mercurial > hg > CbC > CbC_gcc
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gcc-8.2
| author | mir3636 |
|---|---|
| date | Thu, 25 Oct 2018 07:37:49 +0900 |
| parents | 04ced10e8804 |
| children | 1830386684a0 |
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------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- T Y P E S -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2018, 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. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- <http://www.gnu.org/licenses/>. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package contains host independent type definitions which are used -- in more than one unit in the compiler. They are gathered here for easy -- reference, although in some cases the full description is found in the -- relevant module which implements the definition. The main reason that they -- are not in their "natural" specs is that this would cause a lot of inter- -- spec dependencies, and in particular some awkward circular dependencies -- would have to be dealt with. -- WARNING: There is a C version of this package. Any changes to this source -- file must be properly reflected in the C header file types.h declarations. -- Note: the declarations in this package reflect an expectation that the host -- machine has an efficient integer base type with a range at least 32 bits -- 2s-complement. If there are any machines for which this is not a correct -- assumption, a significant number of changes will be required. with System; with Unchecked_Conversion; with Unchecked_Deallocation; package Types is pragma Preelaborate; ------------------------------- -- General Use Integer Types -- ------------------------------- type Int is range -2 ** 31 .. +2 ** 31 - 1; -- Signed 32-bit integer subtype Nat is Int range 0 .. Int'Last; -- Non-negative Int values subtype Pos is Int range 1 .. Int'Last; -- Positive Int values type Word is mod 2 ** 32; -- Unsigned 32-bit integer type Short is range -32768 .. +32767; for Short'Size use 16; -- 16-bit signed integer type Byte is mod 2 ** 8; for Byte'Size use 8; -- 8-bit unsigned integer type size_t is mod 2 ** Standard'Address_Size; -- Memory size value, for use in calls to C routines -------------------------------------- -- 8-Bit Character and String Types -- -------------------------------------- -- We use Standard.Character and Standard.String freely, since we are -- compiling ourselves, and we properly implement the required 8-bit -- character code as required in Ada 95. This section defines a few -- general use constants and subtypes. EOF : constant Character := ASCII.SUB; -- The character SUB (16#1A#) is used in DOS and other systems derived -- from DOS (XP, NT etc) to signal the end of a text file. Internally -- all source files are ended by an EOF character, even on Unix systems. -- An EOF character acts as the end of file only as the last character -- of a source buffer, in any other position, it is treated as a blank -- if it appears between tokens, and as an illegal character otherwise. -- This makes life easier dealing with files that originated from DOS, -- including concatenated files with interspersed EOF characters. subtype Graphic_Character is Character range ' ' .. '~'; -- Graphic characters, as defined in ARM subtype Line_Terminator is Character range ASCII.LF .. ASCII.CR; -- Line terminator characters (LF, VT, FF, CR). For further details, see -- the extensive discussion of line termination in the Sinput spec. subtype Upper_Half_Character is Character range Character'Val (16#80#) .. Character'Val (16#FF#); -- 8-bit Characters with the upper bit set type Character_Ptr is access all Character; type String_Ptr is access all String; type String_Ptr_Const is access constant String; -- Standard character and string pointers procedure Free is new Unchecked_Deallocation (String, String_Ptr); -- Procedure for freeing dynamically allocated String values subtype Big_String is String (Positive); type Big_String_Ptr is access all Big_String; -- Virtual type for handling imported big strings. Note that we should -- never have any allocators for this type, but we don't give a storage -- size of zero, since there are legitimate deallocations going on. function To_Big_String_Ptr is new Unchecked_Conversion (System.Address, Big_String_Ptr); -- Used to obtain Big_String_Ptr values from external addresses subtype Word_Hex_String is String (1 .. 8); -- Type used to represent Word value as 8 hex digits, with lower case -- letters for the alphabetic cases. function Get_Hex_String (W : Word) return Word_Hex_String; -- Convert word value to 8-character hex string ----------------------------------------- -- Types Used for Text Buffer Handling -- ----------------------------------------- -- We can not use type String for text buffers, since we must use the -- standard 32-bit integer as an index value, since we count on all index -- values being the same size. type Text_Ptr is new Int; -- Type used for subscripts in text buffer type Text_Buffer is array (Text_Ptr range <>) of Character; -- Text buffer used to hold source file or library information file type Text_Buffer_Ptr is access all Text_Buffer; -- Text buffers for input files are allocated dynamically and this type -- is used to reference these text buffers. procedure Free is new Unchecked_Deallocation (Text_Buffer, Text_Buffer_Ptr); -- Procedure for freeing dynamically allocated text buffers ------------------------------------------ -- Types Used for Source Input Handling -- ------------------------------------------ type Logical_Line_Number is range 0 .. Int'Last; for Logical_Line_Number'Size use 32; -- Line number type, used for storing logical line numbers (i.e. line -- numbers that include effects of any Source_Reference pragmas in the -- source file). The value zero indicates a line containing a source -- reference pragma. No_Line_Number : constant Logical_Line_Number := 0; -- Special value used to indicate no line number type Physical_Line_Number is range 1 .. Int'Last; for Physical_Line_Number'Size use 32; -- Line number type, used for storing physical line numbers (i.e. line -- numbers in the physical file being compiled, unaffected by the presence -- of source reference pragmas). type Column_Number is range 0 .. 32767; for Column_Number'Size use 16; -- Column number (assume that 2**15 - 1 is large enough). The range for -- this type is used to compute Hostparm.Max_Line_Length. See also the -- processing for -gnatyM in Stylesw). No_Column_Number : constant Column_Number := 0; -- Special value used to indicate no column number Source_Align : constant := 2 ** 12; -- Alignment requirement for source buffers (by keeping source buffers -- aligned, we can optimize the implementation of Get_Source_File_Index. -- See this routine in Sinput for details. subtype Source_Buffer is Text_Buffer; -- Type used to store text of a source file. The buffer for the main -- source (the source specified on the command line) has a lower bound -- starting at zero. Subsequent subsidiary sources have lower bounds -- which are one greater than the previous upper bound, rounded up to -- a multiple of Source_Align. type Source_Buffer_Ptr_Var is access all Source_Buffer; type Source_Buffer_Ptr is access constant Source_Buffer; -- Pointer to source buffer. Source_Buffer_Ptr_Var is used for allocation -- and deallocation; Source_Buffer_Ptr is used for all other uses of source -- buffers. function Null_Source_Buffer_Ptr (X : Source_Buffer_Ptr) return Boolean; -- True if X = null function Source_Buffer_Ptr_Equal (X, Y : Source_Buffer_Ptr) return Boolean renames "="; -- Squirrel away the predefined "=", for use in Null_Source_Buffer_Ptr. -- Do not call this elsewhere. function "=" (X, Y : Source_Buffer_Ptr) return Boolean is abstract; -- Make "=" abstract. Note that this makes "/=" abstract as well. This is a -- vestige of the zero-origin array indexing we used to use, where "=" is -- always wrong (including the one in Null_Source_Buffer_Ptr). We keep this -- just because we never need to compare Source_Buffer_Ptrs other than to -- null. subtype Source_Ptr is Text_Ptr; -- Type used to represent a source location, which is a subscript of a -- character in the source buffer. As noted above, different source buffers -- have different ranges, so it is possible to tell from a Source_Ptr value -- which source it refers to. Note that negative numbers are allowed to -- accommodate the following special values. No_Location : constant Source_Ptr := -1; -- Value used to indicate no source position set in a node. A test for a -- Source_Ptr value being > No_Location is the approved way to test for a -- standard value that does not include No_Location or any of the following -- special definitions. One important use of No_Location is to label -- generated nodes that we don't want the debugger to see in normal mode -- (very often we conditionalize so that we set No_Location in normal mode -- and the corresponding source line in -gnatD mode). Standard_Location : constant Source_Ptr := -2; -- Used for all nodes in the representation of package Standard other than -- nodes representing the contents of Standard.ASCII. Note that testing for -- a value being <= Standard_Location tests for both Standard_Location and -- for Standard_ASCII_Location. Standard_ASCII_Location : constant Source_Ptr := -3; -- Used for all nodes in the presentation of package Standard.ASCII System_Location : constant Source_Ptr := -4; -- Used to identify locations of pragmas scanned by Targparm, where we know -- the location is in System, but we don't know exactly what line. First_Source_Ptr : constant Source_Ptr := 0; -- Starting source pointer index value for first source program ------------------------------------- -- Range Definitions for Tree Data -- ------------------------------------- -- The tree has fields that can hold any of the following types: -- Pointers to other tree nodes (type Node_Id) -- List pointers (type List_Id) -- Element list pointers (type Elist_Id) -- Names (type Name_Id) -- Strings (type String_Id) -- Universal integers (type Uint) -- Universal reals (type Ureal) -- These types are represented as integer indices into various tables. -- However, they should be treated as private, except in a few documented -- cases. In particular it is never appropriate to perform arithmetic -- operations using these types. -- In most contexts, the strongly typed interface determines which of these -- types is present. However, there are some situations (involving untyped -- traversals of the tree), where it is convenient to be easily able to -- distinguish these values. The underlying representation in all cases is -- an integer type Union_Id, and we ensure that the range of the various -- possible values for each of the above types is disjoint so that this -- distinction is possible. -- Note: it is also helpful for debugging purposes to make these ranges -- distinct. If a bug leads to misidentification of a value, then it will -- typically result in an out of range value and a Constraint_Error. type Union_Id is new Int; -- The type in the tree for a union of possible ID values List_Low_Bound : constant := -100_000_000; -- The List_Id values are subscripts into an array of list headers which -- has List_Low_Bound as its lower bound. This value is chosen so that all -- List_Id values are negative, and the value zero is in the range of both -- List_Id and Node_Id values (see further description below). List_High_Bound : constant := 0; -- Maximum List_Id subscript value. This allows up to 100 million list Id -- values, which is in practice infinite, and there is no need to check the -- range. The range overlaps the node range by one element (with value -- zero), which is used both for the Empty node, and for indicating no -- list. The fact that the same value is used is convenient because it -- means that the default value of Empty applies to both nodes and lists, -- and also is more efficient to test for. Node_Low_Bound : constant := 0; -- The tree Id values start at zero, because we use zero for Empty (to -- allow a zero test for Empty). Actual tree node subscripts start at 0 -- since Empty is a legitimate node value. Node_High_Bound : constant := 099_999_999; -- Maximum number of nodes that can be allocated is 100 million, which -- is in practice infinite, and there is no need to check the range. Elist_Low_Bound : constant := 100_000_000; -- The Elist_Id values are subscripts into an array of elist headers which -- has Elist_Low_Bound as its lower bound. Elist_High_Bound : constant := 199_999_999; -- Maximum Elist_Id subscript value. This allows up to 100 million Elists, -- which is in practice infinite and there is no need to check the range. Elmt_Low_Bound : constant := 200_000_000; -- Low bound of element Id values. The use of these values is internal to -- the Elists package, but the definition of the range is included here -- since it must be disjoint from other Id values. The Elmt_Id values are -- subscripts into an array of list elements which has this as lower bound. Elmt_High_Bound : constant := 299_999_999; -- Upper bound of Elmt_Id values. This allows up to 100 million element -- list members, which is in practice infinite (no range check needed). Names_Low_Bound : constant := 300_000_000; -- Low bound for name Id values Names_High_Bound : constant := 399_999_999; -- Maximum number of names that can be allocated is 100 million, which is -- in practice infinite and there is no need to check the range. Strings_Low_Bound : constant := 400_000_000; -- Low bound for string Id values Strings_High_Bound : constant := 499_999_999; -- Maximum number of strings that can be allocated is 100 million, which -- is in practice infinite and there is no need to check the range. Ureal_Low_Bound : constant := 500_000_000; -- Low bound for Ureal values Ureal_High_Bound : constant := 599_999_999; -- Maximum number of Ureal values stored is 100_000_000 which is in -- practice infinite so that no check is required. Uint_Low_Bound : constant := 600_000_000; -- Low bound for Uint values Uint_Table_Start : constant := 2_000_000_000; -- Location where table entries for universal integers start (see -- Uintp spec for details of the representation of Uint values). Uint_High_Bound : constant := 2_099_999_999; -- The range of Uint values is very large, since a substantial part -- of this range is used to store direct values, see Uintp for details. -- The following subtype definitions are used to provide convenient names -- for membership tests on Int values to see what data type range they -- lie in. Such tests appear only in the lowest level packages. subtype List_Range is Union_Id range List_Low_Bound .. List_High_Bound; subtype Node_Range is Union_Id range Node_Low_Bound .. Node_High_Bound; subtype Elist_Range is Union_Id range Elist_Low_Bound .. Elist_High_Bound; subtype Elmt_Range is Union_Id range Elmt_Low_Bound .. Elmt_High_Bound; subtype Names_Range is Union_Id range Names_Low_Bound .. Names_High_Bound; subtype Strings_Range is Union_Id range Strings_Low_Bound .. Strings_High_Bound; subtype Uint_Range is Union_Id range Uint_Low_Bound .. Uint_High_Bound; subtype Ureal_Range is Union_Id range Ureal_Low_Bound .. Ureal_High_Bound; ----------------------------- -- Types for Atree Package -- ----------------------------- -- Node_Id values are used to identify nodes in the tree. They are -- subscripts into the Nodes table declared in package Atree. Note that -- the special values Empty and Error are subscripts into this table. -- See package Atree for further details. type Node_Id is range Node_Low_Bound .. Node_High_Bound; -- Type used to identify nodes in the tree subtype Entity_Id is Node_Id; -- A synonym for node types, used in the Einfo package to refer to nodes -- that are entities (i.e. nodes with an Nkind of N_Defining_xxx). All such -- nodes are extended nodes and these are the only extended nodes, so that -- in practice entity and extended nodes are synonymous. subtype Node_Or_Entity_Id is Node_Id; -- A synonym for node types, used in cases where a given value may be used -- to represent either a node or an entity. We like to minimize such uses -- for obvious reasons of logical type consistency, but where such uses -- occur, they should be documented by use of this type. Empty : constant Node_Id := Node_Low_Bound; -- Used to indicate null node. A node is actually allocated with this -- Id value, so that Nkind (Empty) = N_Empty. Note that Node_Low_Bound -- is zero, so Empty = No_List = zero. Empty_List_Or_Node : constant := 0; -- This constant is used in situations (e.g. initializing empty fields) -- where the value set will be used to represent either an empty node or -- a non-existent list, depending on the context. Error : constant Node_Id := Node_Low_Bound + 1; -- Used to indicate an error in the source program. A node is actually -- allocated with this Id value, so that Nkind (Error) = N_Error. Empty_Or_Error : constant Node_Id := Error; -- Since Empty and Error are the first two Node_Id values, the test for -- N <= Empty_Or_Error tests to see if N is Empty or Error. This definition -- provides convenient self-documentation for such tests. First_Node_Id : constant Node_Id := Node_Low_Bound; -- Subscript of first allocated node. Note that Empty and Error are both -- allocated nodes, whose Nkind fields can be accessed without error. ------------------------------ -- Types for Nlists Package -- ------------------------------ -- List_Id values are used to identify node lists stored in the tree, so -- that each node can be on at most one such list (see package Nlists for -- further details). Note that the special value Error_List is a subscript -- in this table, but the value No_List is *not* a valid subscript, and any -- attempt to apply list operations to No_List will cause a (detected) -- error. type List_Id is range List_Low_Bound .. List_High_Bound; -- Type used to identify a node list No_List : constant List_Id := List_High_Bound; -- Used to indicate absence of a list. Note that the value is zero, which -- is the same as Empty, which is helpful in initializing nodes where a -- value of zero can represent either an empty node or an empty list. Error_List : constant List_Id := List_Low_Bound; -- Used to indicate that there was an error in the source program in a -- context which would normally require a list. This node appears to be -- an empty list to the list operations (a null list is actually allocated -- which has this Id value). First_List_Id : constant List_Id := Error_List; -- Subscript of first allocated list header ------------------------------ -- Types for Elists Package -- ------------------------------ -- Element list Id values are used to identify element lists stored outside -- of the tree, allowing nodes to be members of more than one such list -- (see package Elists for further details). type Elist_Id is range Elist_Low_Bound .. Elist_High_Bound; -- Type used to identify an element list (Elist header table subscript) No_Elist : constant Elist_Id := Elist_Low_Bound; -- Used to indicate absence of an element list. Note that this is not an -- actual Elist header, so element list operations on this value are not -- valid. First_Elist_Id : constant Elist_Id := No_Elist + 1; -- Subscript of first allocated Elist header -- Element Id values are used to identify individual elements of an element -- list (see package Elists for further details). type Elmt_Id is range Elmt_Low_Bound .. Elmt_High_Bound; -- Type used to identify an element list No_Elmt : constant Elmt_Id := Elmt_Low_Bound; -- Used to represent empty element First_Elmt_Id : constant Elmt_Id := No_Elmt + 1; -- Subscript of first allocated Elmt table entry ------------------------------- -- Types for Stringt Package -- ------------------------------- -- String_Id values are used to identify entries in the strings table. They -- are subscripts into the Strings table defined in package Stringt. type String_Id is range Strings_Low_Bound .. Strings_High_Bound; -- Type used to identify entries in the strings table No_String : constant String_Id := Strings_Low_Bound; -- Used to indicate missing string Id. Note that the value zero is used -- to indicate a missing data value for all the Int types in this section. First_String_Id : constant String_Id := No_String + 1; -- First subscript allocated in string table ------------------------- -- Character Code Type -- ------------------------- -- The type Char is used for character data internally in the compiler, but -- character codes in the source are represented by the Char_Code type. -- Each character literal in the source is interpreted as being one of the -- 16#7FFF_FFFF# possible Wide_Wide_Character codes, and a unique Integer -- value is assigned, corresponding to the UTF-32 value, which also -- corresponds to the Pos value in the Wide_Wide_Character type, and also -- corresponds to the Pos value in the Wide_Character and Character types -- for values that are in appropriate range. String literals are similarly -- interpreted as a sequence of such codes. type Char_Code_Base is mod 2 ** 32; for Char_Code_Base'Size use 32; subtype Char_Code is Char_Code_Base range 0 .. 16#7FFF_FFFF#; for Char_Code'Value_Size use 32; for Char_Code'Object_Size use 32; function Get_Char_Code (C : Character) return Char_Code; pragma Inline (Get_Char_Code); -- Function to obtain internal character code from source character. For -- the moment, the internal character code is simply the Pos value of the -- input source character, but we provide this interface for possible -- later support of alternative character sets. function In_Character_Range (C : Char_Code) return Boolean; pragma Inline (In_Character_Range); -- Determines if the given character code is in range of type Character, -- and if so, returns True. If not, returns False. function In_Wide_Character_Range (C : Char_Code) return Boolean; pragma Inline (In_Wide_Character_Range); -- Determines if the given character code is in range of the type -- Wide_Character, and if so, returns True. If not, returns False. function Get_Character (C : Char_Code) return Character; pragma Inline (Get_Character); -- For a character C that is in Character range (see above function), this -- function returns the corresponding Character value. It is an error to -- call Get_Character if C is not in Character range. function Get_Wide_Character (C : Char_Code) return Wide_Character; -- For a character C that is in Wide_Character range (see above function), -- this function returns the corresponding Wide_Character value. It is an -- error to call Get_Wide_Character if C is not in Wide_Character range. --------------------------------------- -- Types used for Library Management -- --------------------------------------- type Unit_Number_Type is new Int range -1 .. Int'Last; -- Unit number. The main source is unit 0, and subsidiary sources have -- non-zero numbers starting with 1. Unit numbers are used to index the -- Units table in package Lib. Main_Unit : constant Unit_Number_Type := 0; -- Unit number value for main unit No_Unit : constant Unit_Number_Type := -1; -- Special value used to signal no unit type Source_File_Index is new Int range -1 .. Int'Last; -- Type used to index the source file table (see package Sinput) No_Source_File : constant Source_File_Index := 0; -- Value used to indicate no source file present No_Access_To_Source_File : constant Source_File_Index := -1; -- Value used to indicate a source file is present but unreadable ----------------------------------- -- Representation of Time Stamps -- ----------------------------------- -- All compiled units are marked with a time stamp which is derived from -- the source file (we assume that the host system has the concept of a -- file time stamp which is modified when a file is modified). These -- time stamps are used to ensure consistency of the set of units that -- constitutes a library. Time stamps are 14-character strings with -- with the following format: -- YYYYMMDDHHMMSS -- YYYY year -- MM month (2 digits 01-12) -- DD day (2 digits 01-31) -- HH hour (2 digits 00-23) -- MM minutes (2 digits 00-59) -- SS seconds (2 digits 00-59) -- In the case of Unix systems (and other systems which keep the time in -- GMT), the time stamp is the GMT time of the file, not the local time. -- This solves problems in using libraries across networks with clients -- spread across multiple time-zones. Time_Stamp_Length : constant := 14; -- Length of time stamp value subtype Time_Stamp_Index is Natural range 1 .. Time_Stamp_Length; type Time_Stamp_Type is new String (Time_Stamp_Index); -- Type used to represent time stamp Empty_Time_Stamp : constant Time_Stamp_Type := (others => ' '); -- Value representing an empty or missing time stamp. Looks less than any -- real time stamp if two time stamps are compared. Note that although this -- is not private, clients should not rely on the exact way in which this -- string is represented, and instead should use the subprograms below. Dummy_Time_Stamp : constant Time_Stamp_Type := (others => '0'); -- This is used for dummy time stamp values used in the D lines for -- non-existent files, and is intended to be an impossible value. function "=" (Left, Right : Time_Stamp_Type) return Boolean; function "<=" (Left, Right : Time_Stamp_Type) return Boolean; function ">=" (Left, Right : Time_Stamp_Type) return Boolean; function "<" (Left, Right : Time_Stamp_Type) return Boolean; function ">" (Left, Right : Time_Stamp_Type) return Boolean; -- Comparison functions on time stamps. Note that two time stamps are -- defined as being equal if they have the same day/month/year and the -- hour/minutes/seconds values are within 2 seconds of one another. This -- deals with rounding effects in library file time stamps caused by -- copying operations during installation. We have particularly noticed -- that WinNT seems susceptible to such changes. -- -- Note: the Empty_Time_Stamp value looks equal to itself, and less than -- any non-empty time stamp value. procedure Split_Time_Stamp (TS : Time_Stamp_Type; Year : out Nat; Month : out Nat; Day : out Nat; Hour : out Nat; Minutes : out Nat; Seconds : out Nat); -- Given a time stamp, decompose it into its components procedure Make_Time_Stamp (Year : Nat; Month : Nat; Day : Nat; Hour : Nat; Minutes : Nat; Seconds : Nat; TS : out Time_Stamp_Type); -- Given the components of a time stamp, initialize the value ------------------------------------- -- Types used for Check Management -- ------------------------------------- type Check_Id is new Nat; -- Type used to represent a check id No_Check_Id : constant := 0; -- Check_Id value used to indicate no check Access_Check : constant := 1; Accessibility_Check : constant := 2; Alignment_Check : constant := 3; Allocation_Check : constant := 4; Atomic_Synchronization : constant := 5; Discriminant_Check : constant := 6; Division_Check : constant := 7; Duplicated_Tag_Check : constant := 8; Elaboration_Check : constant := 9; Index_Check : constant := 10; Length_Check : constant := 11; Overflow_Check : constant := 12; Predicate_Check : constant := 13; Range_Check : constant := 14; Storage_Check : constant := 15; Tag_Check : constant := 16; Validity_Check : constant := 17; Container_Checks : constant := 18; Tampering_Check : constant := 19; -- Values used to represent individual predefined checks (including the -- setting of Atomic_Synchronization, which is implemented internally using -- a "check" whose name is Atomic_Synchronization). All_Checks : constant := 20; -- Value used to represent All_Checks value subtype Predefined_Check_Id is Check_Id range 1 .. All_Checks; -- Subtype for predefined checks, including All_Checks -- The following array contains an entry for each recognized check name -- for pragma Suppress. It is used to represent current settings of scope -- based suppress actions from pragma Suppress or command line settings. -- Note: when Suppress_Array (All_Checks) is True, then generally all other -- specific check entries are set True, except for the Elaboration_Check -- entry which is set only if an explicit Suppress for this check is given. -- The reason for this non-uniformity is that we do not want All_Checks to -- suppress elaboration checking when using the static elaboration model. -- We recognize only an explicit suppress of Elaboration_Check as a signal -- that the static elaboration checking should skip a compile time check. type Suppress_Array is array (Predefined_Check_Id) of Boolean; pragma Pack (Suppress_Array); -- To add a new check type to GNAT, the following steps are required: -- 1. Add an entry to Snames spec for the new name -- 2. Add an entry to the definition of Check_Id above -- 3. Add a new function to Checks to handle the new check test -- 4. Add a new Do_xxx_Check flag to Sinfo (if required) -- 5. Add appropriate checks for the new test -- The following provides precise details on the mode used to generate -- code for intermediate operations in expressions for signed integer -- arithmetic (and how to generate overflow checks if enabled). Note -- that this only affects handling of intermediate results. The final -- result must always fit within the target range, and if overflow -- checking is enabled, the check on the final result is against this -- target range. type Overflow_Mode_Type is ( Not_Set, -- Dummy value used during initialization process to show that the -- corresponding value has not yet been initialized. Strict, -- Operations are done in the base type of the subexpression. If -- overflow checks are enabled, then the check is against the range -- of this base type. Minimized, -- Where appropriate, intermediate arithmetic operations are performed -- with an extended range, using Long_Long_Integer if necessary. If -- overflow checking is enabled, then the check is against the range -- of Long_Long_Integer. Eliminated); -- In this mode arbitrary precision arithmetic is used as needed to -- ensure that it is impossible for intermediate arithmetic to cause an -- overflow. In this mode, intermediate expressions are not affected by -- the overflow checking mode, since overflows are eliminated. subtype Minimized_Or_Eliminated is Overflow_Mode_Type range Minimized .. Eliminated; -- Define subtype so that clients don't need to know ordering. Note that -- Overflow_Mode_Type is not marked as an ordered enumeration type. -- The following structure captures the state of check suppression or -- activation at a particular point in the program execution. type Suppress_Record is record Suppress : Suppress_Array; -- Indicates suppression status of each possible check Overflow_Mode_General : Overflow_Mode_Type; -- This field indicates the mode for handling code generation and -- overflow checking (if enabled) for intermediate expression values. -- This applies to general expressions outside assertions. Overflow_Mode_Assertions : Overflow_Mode_Type; -- This field indicates the mode for handling code generation and -- overflow checking (if enabled) for intermediate expression values. -- This applies to any expression occuring inside assertions. end record; ----------------------------------- -- Global Exception Declarations -- ----------------------------------- -- This section contains declarations of exceptions that are used -- throughout the compiler or in other GNAT tools. Unrecoverable_Error : exception; -- This exception is raised to immediately terminate the compilation of the -- current source program. Used in situations where things are bad enough -- that it doesn't seem worth continuing (e.g. max errors reached, or a -- required file is not found). Also raised when the compiler finds itself -- in trouble after an error (see Comperr). Terminate_Program : exception; -- This exception is raised to immediately terminate the tool being -- executed. Each tool where this exception may be raised must have a -- single exception handler that contains only a null statement and that is -- the last statement of the program. If needed, procedure Set_Exit_Status -- is called with the appropriate exit status before raising -- Terminate_Program. --------------------------------- -- Parameter Mechanism Control -- --------------------------------- -- Function and parameter entities have a field that records the passing -- mechanism. See specification of Sem_Mech for full details. The following -- subtype is used to represent values of this type: subtype Mechanism_Type is Int range -2 .. Int'Last; -- Type used to represent a mechanism value. This is a subtype rather than -- a type to avoid some annoying processing problems with certain routines -- in Einfo (processing them to create the corresponding C). The values in -- the range -2 .. 0 are used to represent mechanism types declared as -- named constants in the spec of Sem_Mech. Positive values are used for -- the case of a pragma C_Pass_By_Copy that sets a threshold value for the -- mechanism to be used. For example if pragma C_Pass_By_Copy (32) is given -- then Default_C_Record_Mechanism is set to 32, and the meaning is to use -- By_Reference if the size is greater than 32, and By_Copy otherwise. ------------------------------ -- Run-Time Exception Codes -- ------------------------------ -- When the code generator generates a run-time exception, it provides a -- reason code which is one of the following. This reason code is used to -- select the appropriate run-time routine to be called, determining both -- the exception to be raised, and the message text to be added. -- The prefix CE/PE/SE indicates the exception to be raised -- CE = Constraint_Error -- PE = Program_Error -- SE = Storage_Error -- The remaining part of the name indicates the message text to be added, -- where all letters are lower case, and underscores are converted to -- spaces (for example CE_Invalid_Data adds the text "invalid data"). -- To add a new code, you need to do the following: -- 1. Assign a new number to the reason. Do not renumber existing codes, -- since this causes compatibility/bootstrap issues, so always add the -- new code at the end of the list. -- 2. Update the contents of the array Kind -- 3. Modify the corresponding definitions in types.h, including the -- definition of last_reason_code. -- 4. Add the name of the routines in exp_ch11.Get_RT_Exception_Name -- 5. Add a new routine in Ada.Exceptions with the appropriate call and -- static string constant. Note that there is more than one version -- of a-except.adb which must be modified. -- Note on ordering of references. For the tables in Ada.Exceptions units, -- usually the ordering does not matter, and we use the same ordering as -- is used here. type RT_Exception_Code is (CE_Access_Check_Failed, -- 00 CE_Access_Parameter_Is_Null, -- 01 CE_Discriminant_Check_Failed, -- 02 CE_Divide_By_Zero, -- 03 CE_Explicit_Raise, -- 04 CE_Index_Check_Failed, -- 05 CE_Invalid_Data, -- 06 CE_Length_Check_Failed, -- 07 CE_Null_Exception_Id, -- 08 CE_Null_Not_Allowed, -- 09 CE_Overflow_Check_Failed, -- 10 CE_Partition_Check_Failed, -- 11 CE_Range_Check_Failed, -- 12 CE_Tag_Check_Failed, -- 13 PE_Access_Before_Elaboration, -- 14 PE_Accessibility_Check_Failed, -- 15 PE_Address_Of_Intrinsic, -- 16 PE_Aliased_Parameters, -- 17 PE_All_Guards_Closed, -- 18 PE_Bad_Predicated_Generic_Type, -- 19 PE_Current_Task_In_Entry_Body, -- 20 PE_Duplicated_Entry_Address, -- 21 PE_Explicit_Raise, -- 22 PE_Finalize_Raised_Exception, -- 23 PE_Implicit_Return, -- 24 PE_Misaligned_Address_Value, -- 25 PE_Missing_Return, -- 26 PE_Overlaid_Controlled_Object, -- 27 PE_Potentially_Blocking_Operation, -- 28 PE_Stubbed_Subprogram_Called, -- 29 PE_Unchecked_Union_Restriction, -- 30 PE_Non_Transportable_Actual, -- 31 SE_Empty_Storage_Pool, -- 32 SE_Explicit_Raise, -- 33 SE_Infinite_Recursion, -- 34 SE_Object_Too_Large, -- 35 PE_Stream_Operation_Not_Allowed, -- 36 PE_Build_In_Place_Mismatch); -- 37 Last_Reason_Code : constant := RT_Exception_Code'Pos (RT_Exception_Code'Last); -- Last reason code type Reason_Kind is (CE_Reason, PE_Reason, SE_Reason); -- Categorization of reason codes by exception raised Rkind : constant array (RT_Exception_Code range <>) of Reason_Kind := (CE_Access_Check_Failed => CE_Reason, CE_Access_Parameter_Is_Null => CE_Reason, CE_Discriminant_Check_Failed => CE_Reason, CE_Divide_By_Zero => CE_Reason, CE_Explicit_Raise => CE_Reason, CE_Index_Check_Failed => CE_Reason, CE_Invalid_Data => CE_Reason, CE_Length_Check_Failed => CE_Reason, CE_Null_Exception_Id => CE_Reason, CE_Null_Not_Allowed => CE_Reason, CE_Overflow_Check_Failed => CE_Reason, CE_Partition_Check_Failed => CE_Reason, CE_Range_Check_Failed => CE_Reason, CE_Tag_Check_Failed => CE_Reason, PE_Access_Before_Elaboration => PE_Reason, PE_Accessibility_Check_Failed => PE_Reason, PE_Address_Of_Intrinsic => PE_Reason, PE_Aliased_Parameters => PE_Reason, PE_All_Guards_Closed => PE_Reason, PE_Bad_Predicated_Generic_Type => PE_Reason, PE_Current_Task_In_Entry_Body => PE_Reason, PE_Duplicated_Entry_Address => PE_Reason, PE_Explicit_Raise => PE_Reason, PE_Finalize_Raised_Exception => PE_Reason, PE_Implicit_Return => PE_Reason, PE_Misaligned_Address_Value => PE_Reason, PE_Missing_Return => PE_Reason, PE_Overlaid_Controlled_Object => PE_Reason, PE_Potentially_Blocking_Operation => PE_Reason, PE_Stubbed_Subprogram_Called => PE_Reason, PE_Unchecked_Union_Restriction => PE_Reason, PE_Non_Transportable_Actual => PE_Reason, PE_Stream_Operation_Not_Allowed => PE_Reason, PE_Build_In_Place_Mismatch => PE_Reason, SE_Empty_Storage_Pool => SE_Reason, SE_Explicit_Raise => SE_Reason, SE_Infinite_Recursion => SE_Reason, SE_Object_Too_Large => SE_Reason); end Types;