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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- T Y P E S --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2021, 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 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
-- 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 cannot 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.
type Source_Span is record
Ptr, First, Last : Source_Ptr;
end record;
-- Type used to represent a source span, consisting in a main location Ptr,
-- with a First and Last location, such that Ptr in First .. Last
function To_Span (Loc : Source_Ptr) return Source_Span is ((others => Loc));
function To_Span (Ptr, First, Last : Source_Ptr) return Source_Span is
((Ptr, First, Last));
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 usually inappropriate to perform arithmetic
-- operations using these types. One exception is in computing hash
-- functions of 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 (except that
-- List_Id and Node_Id overlap at Empty) 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.
-- The range of Node_Id is most of the nonnegative integers. The other
-- ranges are negative. Uint has a very large range, because a substantial
-- part of this range is used to store direct values; see Uintp for
-- details. The other types have 100 million values, which should be
-- plenty.
type Union_Id is new Int;
-- The type in the tree for a union of possible ID values
-- Following are the Low and High bounds of the various ranges.
List_Low_Bound : constant := -099_999_999;
-- The List_Id values are subscripts into an array of list headers which
-- has List_Low_Bound as its lower bound.
List_High_Bound : constant := 0;
-- Maximum List_Id subscript value. The ranges of List_Id and Node_Id
-- overlap by one element (with value zero), which is used both for the
-- Empty node, and for 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).
Node_High_Bound : constant := 1_999_999_999;
Elist_Low_Bound : constant := -199_999_999;
-- 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 := -100_000_000;
Elmt_Low_Bound : constant := -299_999_999;
-- 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 := -200_000_000;
Names_Low_Bound : constant := -399_999_999;
Names_High_Bound : constant := -300_000_000;
Strings_Low_Bound : constant := -499_999_999;
Strings_High_Bound : constant := -400_000_000;
Ureal_Low_Bound : constant := -599_999_999;
Ureal_High_Bound : constant := -500_000_000;
Uint_Low_Bound : constant := -2_100_000_000;
-- Low bound for Uint values
Uint_Table_Start : constant := -699_999_999;
-- Location where table entries for universal integers start (see
-- Uintp spec for details of the representation of Uint values).
Uint_High_Bound : constant := -600_000_000;
-- 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 with Size => 32;
-- 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 with Size => 32;
-- 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 with Size => 32;
-- 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
with Size => 32;
-- 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;
Characters_Assertion_Check : constant := 6;
Containers_Assertion_Check : constant := 7;
Discriminant_Check : constant := 8;
Division_Check : constant := 9;
Duplicated_Tag_Check : constant := 10;
Elaboration_Check : constant := 11;
Index_Check : constant := 12;
Interfaces_Assertion_Check : constant := 13;
IO_Assertion_Check : constant := 14;
Length_Check : constant := 15;
Numerics_Assertion_Check : constant := 16;
Overflow_Check : constant := 17;
Predicate_Check : constant := 18;
Program_Error_Check : constant := 19;
Range_Check : constant := 20;
Storage_Check : constant := 21;
Strings_Assertion_Check : constant := 22;
System_Assertion_Check : constant := 23;
Tag_Check : constant := 24;
Validity_Check : constant := 25;
Container_Checks : constant := 26;
Tampering_Check : constant := 27;
Tasking_Check : constant := 28;
-- 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 := 29;
-- 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 (very important:
-- these definitions should be in the same order in Snames and here)
-- 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 occurring 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.
---------------------------------
-- Component_Alignment Control --
---------------------------------
-- There are four types of alignment possible for array and record
-- types, and a field in the type entities contains a value of the
-- following type indicating which alignment choice applies. For full
-- details of the meaning of these alignment types, see description
-- of the Component_Alignment pragma.
type Component_Alignment_Kind is (
Calign_Default, -- default alignment
Calign_Component_Size, -- natural alignment for component size
Calign_Component_Size_4, -- natural for size <= 4, 4 for size >= 4
Calign_Storage_Unit); -- all components byte aligned
-----------------------------------
-- Floating Point Representation --
-----------------------------------
type Float_Rep_Kind is (IEEE_Binary);
-- The only one supported now is IEEE 754p conforming binary format, but
-- other formats were supported in the past, and could conceivably be
-- supported in the future, so we keep this singleton enumeration type.
----------------------------
-- Small_Paren_Count_Type --
----------------------------
-- See Paren_Count in Atree for documentation
subtype Small_Paren_Count_Type is Nat range 0 .. 3;
------------------------------
-- 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
pragma Convention (C, RT_Exception_Code);
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);
-- Types for field offsets/sizes used in Seinfo, Sinfo.Nodes and
-- Einfo.Entities:
type Field_Offset is new Nat;
-- Offset of a node field, in units of the size of the field, which is
-- always a power of 2.
subtype Slot_Count is Field_Offset;
-- Count of number of slots. Same type as Field_Offset to avoid
-- proliferation of type conversions.
subtype Field_Size_In_Bits is Field_Offset with Predicate =>
Field_Size_In_Bits in 1 | 2 | 4 | 8 | 32;
subtype Opt_Field_Offset is Field_Offset'Base range -1 .. Field_Offset'Last;
No_Field_Offset : constant Opt_Field_Offset := Opt_Field_Offset'First;
type Offset_Array_Index is new Nat;
type Offset_Array is
array (Offset_Array_Index range <>) of Opt_Field_Offset;
end Types;