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diff --git a/gcc/ada/scos.ads b/gcc/ada/scos.ads new file mode 100644 index 00000000000..b1d99e169fa --- /dev/null +++ b/gcc/ada/scos.ads @@ -0,0 +1,328 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S C O S -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 2009, 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 Source Coverage Obligations. It +-- is used by Par_SCO to build the SCO information before writing it out to +-- the ALI file, and by Get_SCO/Put_SCO to read and write the text form that +-- is used in the ALI file. + +with Types; use Types; + +with GNAT.Table; + +package SCOs is + + -- SCO 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 two tables SCO_Table and SCO_Unit_Table, + -- which are also defined in this unit. + + -- Par_SCO is part of the compiler. It scans the parsed source tree and + -- populates the internal tables. + + -- Get_SCO reads the text lines in ALI format and populates the internal + -- tables with corresponding information. + + -- Put_SCO reads the internal tables and generates text lines in the ALI + -- format. + + -------------------- + -- SCO ALI Format -- + -------------------- + + -- Source coverage obligations are generated on a unit-by-unit basis in the + -- ALI file, using lines that start with the identifying character C. These + -- lines are generated if the -gnatC switch is set. + + -- Sloc Ranges + + -- In several places in the SCO lines, Sloc ranges appear. These are used + -- to indicate the first and last Sloc of some construct in the tree and + -- they have the form: + + -- line:col-line:col + + -- Note that SCO's are generated only for generic templates, not for + -- generic instances (since only the first are part of the source). So + -- we don't need generic instantiation stuff in these line:col items. + + -- SCO File headers + + -- The SCO information follows the cross-reference information, so it + -- need not be read by tools like gnatbind, gnatmake etc. The SCO output + -- is divided into sections, one section for each unit for which SCO's + -- are generated. A SCO section has a header of the form: + + -- C dependency-number filename + + -- This header precedes SCO 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 (i.e. 2 = + -- reference to second generated D line). + + -- 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). + + -- Statements + + -- For the purpose of SCO generation, the notion of statement includes + -- simple statements and also the following declaration types: + + -- type_declaration + -- subtype_declaration + -- object_declaration + -- renaming_declaration + -- generic_instantiation + + -- Statement lines + + -- These lines correspond to a sequence of one or more statements which + -- are always exeecuted in sequence, The first statement may be an entry + -- point (e.g. statement after a label), and the last statement may be + -- an exit point (e.g. an exit statement), but no other entry or exit + -- points may occur within the sequence of statements. The idea is that + -- the sequence can be treated as a single unit from a coverage point of + -- view, if any of the code for the statement sequence is executed, this + -- corresponds to coverage of the entire statement sequence. The form of + -- a statement line in the ALI file is: + + -- CS sloc-range + + -- Exit points + + -- An exit point is a statement that causes transfer of control. Examples + -- are exit statements, raise statements and return statements. The form + -- of an exit point in the ALI file is: + + -- CT sloc-range + + -- Decisions + + -- Decisions represent the most significant section of the SCO lines + + -- Note: in the following description, logical operator includes the + -- short circuited forms (so can be any of AND, OR, XOR, NOT, AND THEN, + -- or OR ELSE). + + -- Decisions are either simple or complex. A simple decision is a boolean + -- expresssion that occurs in the context of a control structure in the + -- source program, including WHILE, IF, EXIT WHEN. Note that a boolean + -- expression in any other context, for example, on the right side of an + -- assignment, is not considered to be a decision. + + -- A complex decision is an occurrence of a logical operator which is not + -- itself an operand of some other logical operator. If any operand of + -- the logical operator is itself a logical operator, this is not a + -- separate decision, it is part of the same decision. + + -- So for example, if we have + + -- A, B, C, D : Boolean; + -- function F (Arg : Boolean) return Boolean); + -- ... + -- A and then (B or else F (C and then D)) + + -- There are two (complex) decisions here: + + -- 1. X and then (Y or else Z) + + -- where X = A, Y = B, and Z = F (C and then D) + + -- 2. C and then D + + -- For each decision, a decision line is generated with the form: + + -- C* expression + + -- Here * is one of the following characters: + + -- I decision in IF statement or conditional expression + -- E decision in EXIT WHEN statement + -- W decision in WHILE iteration scheme + -- X decision appearing in some other expression context + + -- The expression is a prefix polish form indicating the structure of + -- the decision, including logical operators and short circuit forms. + -- The following is a grammar showing the structure of expression: + + -- expression ::= term (if expr is not logical operator) + -- expression ::= & term term (if expr is AND or AND THEN) + -- expression ::= | term term (if expr is OR or OR ELSE) + -- expression ::= ^ term term (if expr is XOR) + -- expression ::= !term (if expr is NOT) + + -- term ::= element + -- term ::= expression + + -- element ::= outcome sloc-range + + -- outcome is one of the following letters: + + -- c condition + -- t true condition + -- f false condition + + -- where t/f are used to mark a condition that has been recognized by + -- the compiler as always being true or false. + + -- & indicates either AND or AND THEN connecting two conditions. In the + -- context of couverture we only permit AND THEN in the source in any + -- case, so & can always be understood to be AND THEN. + + -- | indicates either OR or OR ELSE connection two conditions. In the + -- context of couverture we only permit OR ELSE in the source in any + -- case, so | can always be understood to be OR ELSE. + + -- ^ indicates XOR connecting two conditions. In the context of + -- couverture, we do not permit XOR, so this will never appear. + + -- ! indicates NOT applied to the expression. + + --------------------------------------------------------------------- + -- Internal table used to store Source Coverage Obligations (SCOs) -- + --------------------------------------------------------------------- + + type Source_Location is record + Line : Logical_Line_Number; + Col : Column_Number; + end record; + + No_Source_Location : Source_Location := (No_Line_Number, No_Column_Number); + + type SCO_Table_Entry is record + From : Source_Location; + To : Source_Location; + C1 : Character; + C2 : Character; + Last : Boolean; + end record; + + package SCO_Table is new GNAT.Table ( + Table_Component_Type => SCO_Table_Entry, + Table_Index_Type => Nat, + Table_Low_Bound => 1, + Table_Initial => 500, + Table_Increment => 300); + + -- The SCO_Table_Entry values appear as follows: + + -- Statements + -- C1 = 'S' + -- C2 = ' ' + -- From = starting source location + -- To = ending source location + -- Last = unused + + -- Exit + -- C1 = 'T' + -- C2 = ' ' + -- From = starting source location + -- To = ending source location + -- Last = unused + + -- Simple Decision + -- C1 = 'I', 'E', 'W', 'X' (if/exit/while/expression) + -- C2 = 'c', 't', or 'f' + -- From = starting source location + -- To = ending source location + -- Last = True + + -- Complex Decision + -- C1 = 'I', 'E', 'W', 'X' (if/exit/while/expression) + -- C2 = ' ' + -- From = No_Location + -- To = No_Location + -- Last = False + + -- Operator + -- C1 = '!', '^', '&', '|' + -- C2 = ' ' + -- From = No_Location + -- To = No_Location + -- Last = False + + -- Element + -- C1 = ' ' + -- C2 = 'c', 't', or 'f' (condition/true/false) + -- From = starting source location + -- To = ending source location + -- Last = False for all but the last entry, True for last entry + + -- Note: the sequence starting with a decision, and continuing with + -- operators and elements up to and including the first one labeled with + -- Last=True, indicate the sequence to be output for a complex decision + -- on a single CD decision line. + + ---------------- + -- Unit Table -- + ---------------- + + -- This table keeps track of the units and the corresponding starting and + -- ending indexes (From, To) in the SCO table. Note that entry zero is + -- unused, it is for convenience in calling the sort routine. Thus the + -- real lower bound for active entries is 1. + + type SCO_Unit_Index is new Int; + -- Used to index values in this table. Values start at 1 and are assigned + -- sequentially as entries are constructed. + + type SCO_Unit_Table_Entry is record + File_Name : String_Ptr; + -- Pointer to file name in ALI file + + Dep_Num : Nat; + -- Dependency number in ALI file + + From : Nat; + -- Starting index in SCO_Table of SCO information for this unit + + To : Nat; + -- Ending index in SCO_Table of SCO information for this unit + end record; + + package SCO_Unit_Table is new GNAT.Table ( + Table_Component_Type => SCO_Unit_Table_Entry, + Table_Index_Type => SCO_Unit_Index, + Table_Low_Bound => 0, -- see note above on sorting + Table_Initial => 20, + Table_Increment => 200); + + ----------------- + -- Subprograms -- + ----------------- + + procedure Initialize; + -- Reset tables for a new compilation + + procedure Add_SCO + (From : Source_Location := No_Source_Location; + To : Source_Location := No_Source_Location; + C1 : Character := ' '; + C2 : Character := ' '; + Last : Boolean := False); + -- Adds one entry to SCO table with given field values + +end SCOs; |