opt.ads (Old_Checksums, [...]): New Boolean flags, defaulted to False.

2010-10-26  Vincent Celier  <celier@adacore.com>

	* opt.ads (Old_Checksums, Old_Old_Checksums): New Boolean flags,
	defaulted to False.
	* prj-nmsc.adb (Process_Project_Level_Array_Attributes): When
	processing attribute Toolchain_Version ("Ada"), set Opt.Old_Checksums
	and Opt.Old_Old_Checksums depending on the GNAT version.
	* scng.adb (Accumulate_Token_Checksum_Old): New procedure.
	(Accumulate_Token_Checksum_Old_Old): New procedure.
	(Scan): For keywords, when Opt.Old_Checksums is True, call one of the
	alternative procedures Accumulate_Token_Checksum_Old or
	Accumulate_Token_Checksum_Old_Old, instead of Accumulate_Token_Checksum.

From-SVN: r165959

gcc/ada/ChangeLog

+2010-10-26  Vincent Celier  <celier@adacore.com>
+
+	* opt.ads (Old_Checksums, Old_Old_Checksums): New Boolean flags,
+	defaulted to False.
+	* prj-nmsc.adb (Process_Project_Level_Array_Attributes): When
+	processing attribute Toolchain_Version ("Ada"), set Opt.Old_Checksums
+	and Opt.Old_Old_Checksums depending on the GNAT version.
+	* scng.adb (Accumulate_Token_Checksum_Old): New procedure.
+	(Accumulate_Token_Checksum_Old_Old): New procedure.
+	(Scan): For keywords, when Opt.Old_Checksums is True, call one of the
+	alternative procedures Accumulate_Token_Checksum_Old or
+	Accumulate_Token_Checksum_Old_Old, instead of Accumulate_Token_Checksum.
+
 2010-10-26  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
 	* gcc-interface/utils2.c (build_compound_expr): New function.

gcc/ada/opt.ads

@@ -933,6 +933,13 @@ package Opt is
    --  GNATMAKE
    --  Set to True when an object directory is specified with option -D
 
+   Old_Checksums     : Boolean := False;
+   Old_Old_Checksums : Boolean := False;
+   --  GPRBUILD
+   --  Set to True when the old ways of computing checksums needs to be used.
+   --  For reserved words, the old ways were to use the token value, while the
+   --  new way is to use Tok_Identifier for reserved word too.
+
    One_Compilation_Per_Obj_Dir : Boolean := False;
    --  GNATMAKE, GPRBUILD
    --  Set to True with switch --single-compile-per-obj-dir. When True, there

gcc/ada/prj-nmsc.adb

@@ -2399,6 +2399,53 @@ package body Prj.Nmsc is
                         Lang_Index.Config.Toolchain_Version :=
                           Element.Value.Value;
 
+                        --  We need a complete comment section discussing the
+                        --  need for three versions of the checksum algorithm
+                        --  and what is going on here??? Also Old and Old_Old
+                        --  are rather poor names I would say. How about
+
+                        --    Opt.Checksum_503
+                        --    Opt.Checksum_63
+
+                        --  If the Ada compiler is version 6.3 or before, then
+                        --  checksums need to be computed using the old way.
+
+                        --  Also, how about an abstraction for checking
+                        --  version numbers, something like ???
+
+                        --    if Version_Is_Before (5, 3) ....
+
+                        if Lang_Index.Name = Name_Ada then
+                           declare
+                              Vers : constant String :=
+                                       Get_Name_String (Element.Value.Value);
+                              pragma Assert (Vers'First = 1);
+
+                           begin
+                              if Vers'Length >= 8
+                                and then Vers (1 .. 5) = "GNAT "
+                                and then Vers (7) = '.'
+                                and then
+                                  (Vers (6) < '6'
+                                    or else
+                                      (Vers (6) = '6' and then Vers (8) < '4'))
+                              then
+                                 Opt.Old_Checksums := True;
+
+                                 --  If the Ada compiler is version 5.03 or
+                                 --  before, then checksums need to be computed
+                                 --  using the other old way.
+
+                                 if Vers (6) < '5'
+                                   or else (Vers (6) = '5'
+                                             and then Vers (Vers'Last) < '4')
+                                 then
+                                    Opt.Old_Old_Checksums := True;
+                                 end if;
+                              end if;
+                           end;
+                        end if;
+
                      when Name_Runtime_Library_Dir =>
 
                         --  Attribute Runtime_Library_Dir (<language>)

gcc/ada/scng.adb

@@ -64,6 +64,21 @@ package body Scng is
 
    procedure Accumulate_Token_Checksum;
    pragma Inline (Accumulate_Token_Checksum);
+   --  Called after each numeric literal and identifier/keyword. For keywords,
+   --  the token used is Tok_Identifier. This allows to detect additional
+   --  spaces added in sources when using the builder switch -m.
+
+   procedure Accumulate_Token_Checksum_Old;
+   --  Used in place of Accumulate_Token_Checksum for previous releases, when
+   --  Tok_Some was not included in Token_Type and the actual Token_Type was
+   --  used for keywords. This procedure is never used in the compiler or
+   --  gnatmake.
+
+   procedure Accumulate_Token_Checksum_Old_Old;
+   --  Used in place of Accumulate_Token_Checksum for previous releases, when
+   --  Tok_Interface, Tok_Some, Tok_Synchronized and Tok_Overriding were not
+   --  included in Token_Type and the actual Token_Type was used for keywords.
+   --  This procedure is never used in the compiler or gnatmake.
 
    procedure Accumulate_Checksum (C : Character);
    pragma Inline (Accumulate_Checksum);
@@ -120,6 +135,127 @@ package body Scng is
          Character'Val (Token_Type'Pos (Token)));
    end Accumulate_Token_Checksum;
 
+   -----------------------------------
+   -- Accumulate_Token_Checksum_Old --
+   -----------------------------------
+
+   procedure Accumulate_Token_Checksum_Old is
+   begin
+      --  Individual values of Token_Type are used, instead of subranges, so
+      --  that additions or suppressions of enumerated values in type
+      --  Token_Type are detected by the compiler.
+
+      case Token is
+         when Tok_Integer_Literal | Tok_Real_Literal | Tok_String_Literal |
+              Tok_Char_Literal | Tok_Operator_Symbol | Tok_Identifier |
+              Tok_Double_Asterisk | Tok_Ampersand | Tok_Minus | Tok_Plus |
+              Tok_Asterisk | Tok_Mod | Tok_Rem | Tok_Slash | Tok_New |
+              Tok_Abs | Tok_Others | Tok_Null | Tok_Dot | Tok_Apostrophe |
+              Tok_Left_Paren | Tok_Delta | Tok_Digits | Tok_Range |
+              Tok_Right_Paren | Tok_Comma | Tok_And | Tok_Or | Tok_Xor |
+              Tok_Less | Tok_Equal | Tok_Greater | Tok_Not_Equal |
+              Tok_Greater_Equal | Tok_Less_Equal | Tok_In | Tok_Not |
+              Tok_Box | Tok_Colon_Equal | Tok_Colon | Tok_Greater_Greater |
+              Tok_Abstract | Tok_Access | Tok_Aliased | Tok_All | Tok_Array |
+              Tok_At | Tok_Body | Tok_Constant | Tok_Do | Tok_Is |
+              Tok_Interface | Tok_Limited | Tok_Of | Tok_Out | Tok_Record |
+              Tok_Renames | Tok_Reverse =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token)));
+
+         when Tok_Some =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Tok_Identifier)));
+
+         when Tok_Tagged | Tok_Then | Tok_Less_Less | Tok_Abort | Tok_Accept |
+              Tok_Case | Tok_Delay | Tok_Else | Tok_Elsif | Tok_End |
+              Tok_Exception | Tok_Exit | Tok_Goto | Tok_If | Tok_Pragma |
+              Tok_Raise | Tok_Requeue | Tok_Return | Tok_Select |
+              Tok_Terminate | Tok_Until | Tok_When | Tok_Begin | Tok_Declare |
+              Tok_For | Tok_Loop | Tok_While | Tok_Entry | Tok_Protected |
+              Tok_Task | Tok_Type | Tok_Subtype | Tok_Overriding |
+              Tok_Synchronized | Tok_Use | Tok_Function | Tok_Generic |
+              Tok_Package | Tok_Procedure | Tok_Private | Tok_With |
+              Tok_Separate | Tok_EOF | Tok_Semicolon | Tok_Arrow |
+              Tok_Vertical_Bar | Tok_Dot_Dot | Tok_Project | Tok_Extends |
+              Tok_External | Tok_External_As_List | Tok_Comment |
+              Tok_End_Of_Line | Tok_Special | No_Token =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token_Type'Pred (Token))));
+      end case;
+   end Accumulate_Token_Checksum_Old;
+
+   ---------------------------------------
+   -- Accumulate_Token_Checksum_Old_Old --
+   ---------------------------------------
+
+   procedure Accumulate_Token_Checksum_Old_Old is
+   begin
+      --  Individual values of Token_Type are used, instead of subranges, so
+      --  that additions or suppressions of enumerated values in type
+      --  Token_Type are detected by the compiler.
+
+      case Token is
+         when Tok_Integer_Literal | Tok_Real_Literal | Tok_String_Literal |
+              Tok_Char_Literal | Tok_Operator_Symbol | Tok_Identifier |
+              Tok_Double_Asterisk | Tok_Ampersand | Tok_Minus | Tok_Plus |
+              Tok_Asterisk | Tok_Mod | Tok_Rem | Tok_Slash | Tok_New |
+              Tok_Abs | Tok_Others | Tok_Null | Tok_Dot | Tok_Apostrophe |
+              Tok_Left_Paren | Tok_Delta | Tok_Digits | Tok_Range |
+              Tok_Right_Paren | Tok_Comma | Tok_And | Tok_Or | Tok_Xor |
+              Tok_Less | Tok_Equal | Tok_Greater | Tok_Not_Equal |
+              Tok_Greater_Equal | Tok_Less_Equal | Tok_In | Tok_Not |
+              Tok_Box | Tok_Colon_Equal | Tok_Colon | Tok_Greater_Greater |
+              Tok_Abstract | Tok_Access | Tok_Aliased | Tok_All | Tok_Array |
+              Tok_At | Tok_Body | Tok_Constant | Tok_Do | Tok_Is =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token)));
+
+         when Tok_Interface | Tok_Some | Tok_Overriding | Tok_Synchronized =>
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Tok_Identifier)));
+
+         when Tok_Limited | Tok_Of | Tok_Out | Tok_Record |
+              Tok_Renames | Tok_Reverse =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token) - 1));
+
+         when Tok_Tagged | Tok_Then | Tok_Less_Less | Tok_Abort | Tok_Accept |
+              Tok_Case | Tok_Delay | Tok_Else | Tok_Elsif | Tok_End |
+              Tok_Exception | Tok_Exit | Tok_Goto | Tok_If | Tok_Pragma |
+              Tok_Raise | Tok_Requeue | Tok_Return | Tok_Select |
+              Tok_Terminate | Tok_Until | Tok_When | Tok_Begin | Tok_Declare |
+              Tok_For | Tok_Loop | Tok_While | Tok_Entry | Tok_Protected |
+              Tok_Task | Tok_Type | Tok_Subtype =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token) - 2));
+
+         when Tok_Use | Tok_Function | Tok_Generic |
+              Tok_Package | Tok_Procedure | Tok_Private | Tok_With |
+              Tok_Separate | Tok_EOF | Tok_Semicolon | Tok_Arrow |
+              Tok_Vertical_Bar | Tok_Dot_Dot | Tok_Project | Tok_Extends |
+              Tok_External | Tok_External_As_List | Tok_Comment |
+              Tok_End_Of_Line | Tok_Special | No_Token =>
+
+            System.CRC32.Update
+              (System.CRC32.CRC32 (Checksum),
+               Character'Val (Token_Type'Pos (Token) - 4));
+      end case;
+   end Accumulate_Token_Checksum_Old_Old;
+
    ----------------------------
    -- Determine_Token_Casing --
    ----------------------------
@@ -2413,12 +2549,23 @@ package body Scng is
          --  checksum is independent of the Ada version.
 
          Token := Tok_Identifier;
-         Accumulate_Token_Checksum;
 
          --  Here is where we check if it was a keyword
 
          if Is_Keyword_Name (Token_Name) then
-            Token := Token_Type'Val (Get_Name_Table_Byte (Token_Name));
+            if Opt.Old_Checksums then
+               Token := Token_Type'Val (Get_Name_Table_Byte (Token_Name));
+
+               if Opt.Old_Old_Checksums then
+                  Accumulate_Token_Checksum_Old_Old;
+               else
+                  Accumulate_Token_Checksum_Old;
+               end if;
+
+            else
+               Accumulate_Token_Checksum;
+               Token := Token_Type'Val (Get_Name_Table_Byte (Token_Name));
+            end if;
 
             --  Keyword style checks
 
@@ -2475,6 +2622,7 @@ package body Scng is
          --  It is an identifier after all
 
          else
+            Accumulate_Token_Checksum;
             Post_Scan;
             return;
          end if;