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Diffstat (limited to 'gcc-4.8.3/gcc/ada/alfa.ads')
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diff --git a/gcc-4.8.3/gcc/ada/alfa.ads b/gcc-4.8.3/gcc/ada/alfa.ads new file mode 100644 index 000000000..26c8247cc --- /dev/null +++ b/gcc-4.8.3/gcc/ada/alfa.ads @@ -0,0 +1,363 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- A L F A -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 2011-2012, 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 defines tables used to store information needed for the Alfa +-- mode. It is used by procedures in Lib.Xref.Alfa to build the Alfa +-- information before writing it out to the ALI file, and by Get_Alfa/Put_Alfa +-- to read and write the text form that is used in the ALI file. + +with Types; use Types; +with GNAT.Table; + +package Alfa is + + -- Alfa information can exist in one of two forms. In the ALI file, it is + -- represented using a text format that is described in this specification. + -- Internally it is stored using three tables Alfa_Xref_Table, + -- Alfa_Scope_Table and Alfa_File_Table, which are also defined in this + -- unit. + + -- Lib.Xref.Alfa is part of the compiler. It extracts Alfa information from + -- the complete set of cross-references generated during compilation. + + -- Get_Alfa reads the text lines in ALI format and populates the internal + -- tables with corresponding information. + + -- Put_Alfa reads the internal tables and generates text lines in the ALI + -- format. + + --------------------- + -- Alfa ALI Format -- + --------------------- + + -- Alfa information is generated on a unit-by-unit basis in the ALI file, + -- using lines that start with the identifying character F ("Formal"). + -- These lines are generated if one of the -gnatd.E (SPARK generation mode) + -- or gnatd.F (Why generation mode) switches is set. + + -- The Alfa information follows the cross-reference information, so it + -- needs not be read by tools like gnatbind, gnatmake etc. + + -- ------------------- + -- -- Scope Section -- + -- ------------------- + + -- A first section defines the scopes in which entities are defined and + -- referenced. A scope is a package/subprogram declaration/body. Note that + -- a package declaration and body define two different scopes. Similarly, a + -- subprogram declaration and body, when both present, define two different + -- scopes. + + -- FD dependency-number filename (-> unit-filename)? + + -- This header precedes scope information for the unit identified by + -- dependency number and file name. The dependency number is the index + -- into the generated D lines and is ones-origin (e.g. 2 = reference to + -- second generated D line). + + -- The list of FD lines should match the list of D lines defined in the + -- ALI file, in the same order. + + -- Note that the filename here will reflect the original name if a + -- Source_Reference pragma was encountered (since all line number + -- references will be with respect to the original file). + + -- Note: the filename is redundant in that it could be deduced from the + -- corresponding D line, but it is convenient at least for human + -- reading of the Alfa information, and means that the Alfa information + -- can stand on its own without needing other parts of the ALI file. + + -- The optional unit filename is given only for subunits. + + -- FS . scope line type col entity (-> spec-file . spec-scope)? + + -- (The ? mark stands for an optional entry in the syntax) + + -- scope is the ones-origin scope number for the current file (e.g. 2 = + -- reference to the second FS line in this FD block). + + -- line is the line number of the scope entity. The name of the entity + -- starts in column col. Columns are numbered from one, and if + -- horizontal tab characters are present, the column number is computed + -- assuming standard 1,9,17,.. tab stops. For example, if the entity is + -- the first token on the line, and is preceded by space-HT-space, then + -- the column would be column 10. + + -- type is a single letter identifying the type of the entity, using + -- the same code as in cross-references: + + -- K = package + -- V = function + -- U = procedure + + -- col is the column number of the scope entity + + -- entity is the name of the scope entity, with casing in the canonical + -- casing for the source file where it is defined. + + -- spec-file and spec-scope are respectively the file and scope for the + -- spec corresponding to the current body scope, when they differ. + + -- ------------------ + -- -- Xref Section -- + -- ------------------ + + -- A second section defines cross-references useful for computing the set + -- of global variables read/written in each subprogram/package. + + -- FX dependency-number filename . entity-number entity + + -- dependency-number and filename identity a file in FD lines + + -- entity-number and identity identify a scope entity in FS lines for + -- the file previously identified. + + -- line typ col entity ref* + + -- line is the line number of the referenced entity + + -- typ is the type of the referenced entity, using a code similar to + -- the one used for cross-references: + + -- > = IN parameter + -- < = OUT parameter + -- = = IN OUT parameter + -- * = all other cases + + -- col is the column number of the referenced entity + + -- entity is the name of the referenced entity as written in the source + -- file where it is defined. + + -- There may be zero or more ref entries on each line + + -- (file |)? ((. scope :)? line type col)* + + -- file is the dependency number of the file with the reference. It and + -- the following vertical bar are omitted if the file is the same as + -- the previous ref, and the refs for the current file are first (and + -- do not need a bar). + + -- scope is the scope number of the scope with the reference. It and + -- the following colon are omitted if the scope is the same as the + -- previous ref, and the refs for the current scope are first (and do + -- not need a colon). + + -- line is the line number of the reference + + -- col is the column number of the reference + + -- type is one of the following, using the same code as in + -- cross-references: + + -- m = modification + -- r = reference + -- s = subprogram reference in a static call + + -- Special entries for reads and writes to memory reference a special + -- variable called "__HEAP". These special entries are present in every + -- scope where reads and writes to memory are present. Line and column for + -- this special variable are always 0. + + -- Examples: ??? add examples here + + ---------------- + -- Xref Table -- + ---------------- + + -- The following table records Alfa cross-references + + type Xref_Index is new Int; + -- Used to index values in this table. Values start at 1 and are assigned + -- sequentially as entries are constructed. + + type Alfa_Xref_Record is record + Entity_Name : String_Ptr; + -- Pointer to entity name in ALI file + + Entity_Line : Nat; + -- Line number for the entity referenced + + Etype : Character; + -- Indicates type of entity, using code used in ALI file: + -- > = IN parameter + -- < = OUT parameter + -- = = IN OUT parameter + -- * = all other cases + + Entity_Col : Nat; + -- Column number for the entity referenced + + File_Num : Nat; + -- Set to the file dependency number for the cross-reference. Note + -- that if no file entry is present explicitly, this is just a copy + -- of the reference for the current cross-reference section. + + Scope_Num : Nat; + -- Set to the scope number for the cross-reference. Note that if no + -- scope entry is present explicitly, this is just a copy of the + -- reference for the current cross-reference section. + + Line : Nat; + -- Line number for the reference + + Rtype : Character; + -- Indicates type of reference, using code used in ALI file: + -- r = reference + -- m = modification + -- s = call + + Col : Nat; + -- Column number for the reference + end record; + + package Alfa_Xref_Table is new GNAT.Table ( + Table_Component_Type => Alfa_Xref_Record, + Table_Index_Type => Xref_Index, + Table_Low_Bound => 1, + Table_Initial => 2000, + Table_Increment => 300); + + ----------------- + -- Scope Table -- + ----------------- + + -- This table keeps track of the scopes and the corresponding starting and + -- ending indexes (From, To) in the Xref table. + + type Scope_Index is new Int; + -- Used to index values in this table. Values start at 1 and are assigned + -- sequentially as entries are constructed. + + type Alfa_Scope_Record is record + Scope_Name : String_Ptr; + -- Pointer to scope name in ALI file + + File_Num : Nat; + -- Set to the file dependency number for the scope + + Scope_Num : Nat; + -- Set to the scope number for the scope + + Spec_File_Num : Nat; + -- Set to the file dependency number for the scope corresponding to the + -- spec of the current scope entity, if different, or else 0. + + Spec_Scope_Num : Nat; + -- Set to the scope number for the scope corresponding to the spec of + -- the current scope entity, if different, or else 0. + + Line : Nat; + -- Line number for the scope + + Stype : Character; + -- Indicates type of scope, using code used in ALI file: + -- K = package + -- V = function + -- U = procedure + + Col : Nat; + -- Column number for the scope + + From_Xref : Xref_Index; + -- Starting index in Xref table for this scope + + To_Xref : Xref_Index; + -- Ending index in Xref table for this scope + + -- The following component is only used in-memory, not printed out in + -- ALI file. + + Scope_Entity : Entity_Id := Empty; + -- Entity (subprogram or package) for the scope + end record; + + package Alfa_Scope_Table is new GNAT.Table ( + Table_Component_Type => Alfa_Scope_Record, + Table_Index_Type => Scope_Index, + Table_Low_Bound => 1, + Table_Initial => 200, + Table_Increment => 300); + + ---------------- + -- File Table -- + ---------------- + + -- This table keeps track of the units and the corresponding starting and + -- ending indexes (From, To) in the Scope table. + + type File_Index is new Int; + -- Used to index values in this table. Values start at 1 and are assigned + -- sequentially as entries are constructed. + + type Alfa_File_Record is record + File_Name : String_Ptr; + -- Pointer to file name in ALI file + + Unit_File_Name : String_Ptr; + -- Pointer to file name for unit in ALI file, when File_Name refers to a + -- subunit. Otherwise null. + + File_Num : Nat; + -- Dependency number in ALI file + + From_Scope : Scope_Index; + -- Starting index in Scope table for this unit + + To_Scope : Scope_Index; + -- Ending index in Scope table for this unit + end record; + + package Alfa_File_Table is new GNAT.Table ( + Table_Component_Type => Alfa_File_Record, + Table_Index_Type => File_Index, + Table_Low_Bound => 1, + Table_Initial => 20, + Table_Increment => 200); + + --------------- + -- Constants -- + --------------- + + Name_Of_Heap_Variable : constant String := "__HEAP"; + -- Name of special variable used in effects to denote reads and writes + -- through explicit dereference. + + ----------------- + -- Subprograms -- + ----------------- + + procedure Initialize_Alfa_Tables; + -- Reset tables for a new compilation + + procedure dalfa; + -- Debug routine to dump internal Alfa tables. This is a raw format dump + -- showing exactly what the tables contain. + + procedure palfa; + -- Debugging procedure to output contents of Alfa binary tables in the + -- format in which they appear in an ALI file. + +end Alfa; |