* jump.c: Remove prototypes for delete_computation and
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- A L I . U T I L --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2003 Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
27 -- This child unit provides utility data structures and procedures used
28 -- for manipulation of ALI data by the gnatbind and gnatmake.
30 package ALI.Util is
32 -----------------------
33 -- Source File Table --
34 -----------------------
36 -- A source file table entry is built for every source file that is
37 -- in the source dependency table of any of the ALI files that make
38 -- up the current program.
40 No_Source_Id : constant Source_Id := Source_Id'First;
41 -- Special value indicating no Source table entry
43 First_Source_Entry : constant Source_Id := No_Source_Id + 1;
44 -- Id of first actual entry in table
46 type Source_Record is record
48 Sfile : File_Name_Type;
49 -- Name of source file
51 Stamp : Time_Stamp_Type;
52 -- Time stamp value. If Check_Source_Files is set and the source
53 -- file is located, then Stamp is set from the source file. Otherwise
54 -- Stamp is set from the latest stamp value found in any of the
55 -- ALI files for the current program.
57 Source_Found : Boolean;
58 -- This flag is set to True if the corresponding source file was
59 -- located and the Stamp value was set from the actual source file.
60 -- It is always false if Check_Source_Files is not set.
62 All_Timestamps_Match : Boolean;
63 -- This flag is set only if all files referencing this source file
64 -- have a matching time stamp, and also, if Source_Found is True,
65 -- then the stamp of the source file also matches. If this flag is
66 -- True, then checksums for this file are never referenced. We only
67 -- use checksums if there are time stamp mismatches.
69 All_Checksums_Match : Boolean;
70 -- This flag is set only if all files referencing this source file
71 -- have checksums, and if all these checksums match. If this flag
72 -- is set to True, then the binder will ignore a timestamp mismatch.
73 -- An absent checksum causes this flag to be set False, and a mismatch
74 -- of checksums also causes it to be set False. The checksum of the
75 -- actual source file (if Source_Found is True) is included only if
76 -- All_Timestamps_Match is False (since checksums are only interesting
77 -- if we have time stamp mismatches, and we want to avoid computing the
78 -- checksum of the source file if it is not needed.)
80 Checksum : Word;
81 -- If no dependency line has a checksum for this source file (i.e. the
82 -- corresponding entries in the source dependency records all have the
83 -- Checksum_Present flag set False), then this field is undefined. If
84 -- at least one dependency entry has a checksum present, then this
85 -- field contains one of the possible checksum values that has been
86 -- seen. This is used to set All_Checksums_Match properly.
88 end record;
90 package Source is new Table.Table (
91 Table_Component_Type => Source_Record,
92 Table_Index_Type => Source_Id,
93 Table_Low_Bound => First_Source_Entry,
94 Table_Initial => 1000,
95 Table_Increment => 200,
96 Table_Name => "Source");
98 procedure Initialize_ALI_Source;
99 -- Initialize Source table
101 --------------------------------------------------
102 -- Subprograms for Manipulating ALI Information --
103 --------------------------------------------------
105 procedure Read_ALI (Id : ALI_Id);
106 -- Process an ALI file which has been read and scanned by looping
107 -- through all withed units in the ALI file, checking if they have
108 -- been processed. Each unit that has not yet been processed will
109 -- be read, scanned, and processed recursively.
111 procedure Set_Source_Table (A : ALI_Id);
112 -- Build source table entry corresponding to the ALI file whose id is A.
114 procedure Set_Source_Table;
115 -- Build the entire source table.
117 function Time_Stamp_Mismatch
118 (A : ALI_Id;
119 Read_Only : Boolean := False)
120 return File_Name_Type;
121 -- Looks in the Source_Table and checks time stamp mismatches between
122 -- the sources there and the sources in the Sdep section of ali file whose
123 -- id is A. If no time stamp mismatches are found No_File is returned.
124 -- Otherwise return the first file for which there is a mismatch.
125 -- Note that in check source files mode (Check_Source_Files = True), the
126 -- time stamp in the Source_Table should be the actual time stamp of the
127 -- source files. In minimal recompilation mode (Minimal_Recompilation set
128 -- to True, no mismatch is found if the file's timestamp has not changed.
129 -- If Read_Only is True, missing sources are not considered.
131 --------------------------------------------
132 -- Subprograms for manipulating checksums --
133 --------------------------------------------
135 Checksum_Error : constant Word := 16#FFFF_FFFF#;
136 -- This value is used to indicate an error in computing the checksum.
137 -- When comparing checksums for smart recompilation, the CRC_Error
138 -- value is never considered to match. This could possibly result
139 -- in a false negative, but that is never harmful, it just means
140 -- that in unusual cases an unnecessary recompilation occurs.
142 function Get_File_Checksum (Fname : Name_Id) return Word;
143 -- Compute checksum for the given file. As far as possible, this circuit
144 -- computes exactly the same value computed by the compiler, but it does
145 -- not matter if it gets it wrong in marginal cases, since the only result
146 -- is to miss some smart recompilation cases, correct functioning is not
147 -- affected by a miscomputation. Returns Checksum_Error if the file is
148 -- missing or has an error.
150 function Checksums_Match (Checksum1, Checksum2 : Word) return Boolean;
151 pragma Inline (Checksums_Match);
152 -- Returns True if Checksum1 and Checksum2 have the same value and are
153 -- not equal to Checksum_Error, returns False in all other cases. This
154 -- routine must always be used to compare for checksum equality, to
155 -- ensure that the case of Checksum_Error is handled properly.
157 end ALI.Util;