From cfac6e9fb4ea2fc7b05ded85c805501e4d7700b9 Mon Sep 17 00:00:00 2001 From: Pascal Obry Date: Thu, 11 Oct 2001 23:28:47 +0000 Subject: * Makefile.in: (GNAT_ADA_OBJS): add g-crc32.o, a-tags.o, a-stream.o (GNATBIND_OBJS): add g-crc32.o, a-tags.o, a-stream.o (GNATLS_RTL_OBJS): add g-crc32.o (GNATMAKE_RTL_OBJS): add g-crc32.o * ali-util.adb: (CRC_Match): new function. (Get_File_Checksum): renamed Get_File_CRC. Use the GNAT.CRC32 unit instead of the previous simple checksum algorithm. (Time_Stamp_Mismatch): use CRC_Match for comparison. (Set_Source_Table): idem. * ali-util.ads: (Get_File_Checksum): renamed Get_File_CRC as now we compute CRC instead of simple checksum. (CRC_Match): new function. (CRC_Error): new constant. * ali.adb (Scan_ALI): rename variable Chk to CRC as we are handling a CRC now and not a simple checksum. A CRC uses lower-case hex letters, fixes ambiguity in parsing. * ali.ads (Sdep_Record.Checksum): renamed Sdep_Record.CRC as this is what this variable will store. * bcheck.adb: Change reference to chechsum in comments by CRC. (Check_Consistency): Rename Get_File_Checksum to Get_File_CRC. rename All_Checksum_Match to All_CRC_Match. Change due to API renaming since now GNAT does not use a simple checksum but a CRC using GNAT.CRC32. * gnatls.adb: Rename Checksum to CRC in many places, we use a CRC now and not anymore a simple checksum. * lib-load.adb: Use Source_CRC instead of Source_Checksum in many places. * lib-writ.adb (Write_ALI): Use Source_CRC instead of Source_Checksum. * scans.adb: (Restore_Scan_State): rename Checksum to CRC. (Save_Scan_State): idem. * scans.ads: With GNAT.CRC32. (Checksum): rename to CRC. (Saved_Scan_State): Save_Checksum field renamed to Save_CRC * scn-nlit.adb: Rename many Accumulate_Checksum to Update (from GNAT.CRC32). Update copyright notice. * scn-slit.adb: Rename many Accumulate_Checksum to Update (from GNAT.CRC32). Update copyright notice. * scn.adb: (Accumulate_Checksum): removed. (Update): new procedure. Add a wide-character into the CRC. * sinput-l.adb: (Complete_Source_File_Entry): use CRC32 instead of simple checksum. (Load_File): fix initialization of S (change Source_Checksum to Source_CRC) * sinput-p.adb (Load_Project_File): rename Source_Checksum to Source_CRC in S initialization. * sinput.adb (Source_Checksum): renamed to Source_CRC. * sinput.ads (Source_Checksum): renamed to Source_CRC. Update comments for the CRC. * types.adb (Hex): Use lowercase for the letter part. * types.ads (Get_Hex_String): Returns the hexadecimal representation for a word. This is currently used only for CRC. In previous version, the checksum was using a representation with all letter being upper-case. With the new implementation (using CRC) we do not remove the 32th bit of the CRC, so we can have an upper-case starting letter in the CRC. This is not possible to parse in Scan_ALI (ali.adb). It is ambigous since the CRC was optional and could be followed by options like EB, EE. So now this routines uses lower-case letter for the hexadecimal representation. Strange enough only lower case letters where checked in Scan_ALI (even if this was not a possible case). * gnatvsn.ads (Library_Version): changed to 3.15a. * s-crc32.ads: Initial version from GNAT.CRC32. This is the version for the compiler. * s-crc32.adb: Initial version from GNAT.CRC32. This is the version for the compiler. * ali-util.adb: Redo previous change to avoid using word CRC everywhere Add 2001 to copyright notice (Accumulate_Checksum): Modify to use System.CRC32. * ali-util.ads: Redo changes of previous revision to continue to use the word Checksum. Add 2001 to copyright notice. * ali.adb: Undo some of previous changes, not needed. Keep the change for lower case letters in the checksum. * ali.ads: Undo previous change not needed. * bcheck.adb: Undo most of previous change, not needed. But do use Checksums_Match for checksum comparison. * gnatls.adb: Undo most of previous change, not needed. But do use Checksums_Match for comparing checksums. * lib-load.adb: Undo previous change, not needed. * lib-writ.adb: Undo previous change, not needed. * lib-writ.ads: Document that checksums use lower case, not upper case letters. * scans.adb: Undo previous change, not needed * scans.ads: Undo previous change, not needed. * scn-nlit.adb: Undo previous changes, not needed. * scn-slit.adb: Undo previous change, not needed. Fix header format. * scn.adb: (Accumulate_Checksum): Use System.CRC32. (Initialize_Checksum): New procedure. Remove other changes of previous revision. * sinput-p.adb: Undo previous change, not needed. * sinput.adb: Undo previous change, not needed. * sinput-l.adb: Undo previous change, not needed. * sinput.ads: Undo previous change, not needed. Keep only comment on new checksum algorithm * Makefile.in: Add s-crc32 as needed, remove g-crc32. Also remove a-tags and a-stream from GNAT sources. * ali.adb (Scan_ALI): fix typo introduce in latest check-in. * Makefile.in (GNATRTL_NONTASKING_OBJS): Add g-crc32.o. From-SVN: r46206 --- gcc/ada/ali-util.ads | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) (limited to 'gcc/ada/ali-util.ads') diff --git a/gcc/ada/ali-util.ads b/gcc/ada/ali-util.ads index ace733a..9cfefb7 100644 --- a/gcc/ada/ali-util.ads +++ b/gcc/ada/ali-util.ads @@ -6,9 +6,9 @@ -- -- -- S p e c -- -- -- --- $Revision: 1.2 $ -- +-- $Revision$ -- -- --- Copyright (C) 1992-1999 Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2001 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- -- @@ -130,12 +130,26 @@ package ALI.Util is -- Subprograms for manipulating checksums -- -------------------------------------------- + Checksum_Error : constant Word := 16#FFFF_FFFF#; + -- This value is used to indicate an error in computing the checksum. + -- When comparing checksums for smart recompilation, the CRC_Error + -- value is never considered to match. This could possibly result + -- in a false negative, but that is never harmful, it just means + -- that in unusual cases an unnecessary recompilation occurs. + function Get_File_Checksum (Fname : Name_Id) return Word; -- Compute checksum for the given file. As far as possible, this circuit -- computes exactly the same value computed by the compiler, but it does -- not matter if it gets it wrong in marginal cases, since the only result -- is to miss some smart recompilation cases, correct functioning is not - -- affecte by a mis-computation. Returns an impossible checksum value, - -- with the upper bit set, if the file is missing or has an error. + -- affected by a miscomputation. Returns Checksum_Error if the file is + -- missing or has an error. + + function Checksums_Match (Checksum1, Checksum2 : Word) return Boolean; + pragma Inline (Checksums_Match); + -- Returns True if Checksum1 and Checksum2 have the same value and are + -- not equal to Checksum_Error, returns False in all other cases. This + -- routine must always be used to compare for checksum equality, to + -- ensure that the case of Checksum_Error is handled properly. end ALI.Util; -- cgit v1.1