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Diffstat (limited to 'gcc-4.3.1/gcc/ada/restrict.adb')
| -rw-r--r-- | gcc-4.3.1/gcc/ada/restrict.adb | 800 |
1 files changed, 800 insertions, 0 deletions
diff --git a/gcc-4.3.1/gcc/ada/restrict.adb b/gcc-4.3.1/gcc/ada/restrict.adb new file mode 100644 index 000000000..851340808 --- /dev/null +++ b/gcc-4.3.1/gcc/ada/restrict.adb @@ -0,0 +1,800 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- R E S T R I C T -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1992-2007, 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. -- +-- -- +------------------------------------------------------------------------------ + +with Atree; use Atree; +with Casing; use Casing; +with Errout; use Errout; +with Fname; use Fname; +with Fname.UF; use Fname.UF; +with Lib; use Lib; +with Opt; use Opt; +with Sinfo; use Sinfo; +with Sinput; use Sinput; +with Snames; use Snames; +with Uname; use Uname; + +package body Restrict is + + Restricted_Profile_Result : Boolean := False; + -- This switch memoizes the result of Restricted_Profile function + -- calls for improved efficiency. Its setting is valid only if + -- Restricted_Profile_Cached is True. Note that if this switch + -- is ever set True, it need never be turned off again. + + Restricted_Profile_Cached : Boolean := False; + -- This flag is set to True if the Restricted_Profile_Result + -- contains the correct cached result of Restricted_Profile calls. + + ----------------------- + -- Local Subprograms -- + ----------------------- + + procedure Restriction_Msg (Msg : String; R : String; N : Node_Id); + -- Output error message at node N with given text, replacing the + -- '%' in the message with the name of the restriction given as R, + -- cased according to the current identifier casing. We do not use + -- the normal insertion mechanism, since this requires an entry + -- in the Names table, and this table will be locked if we are + -- generating a message from gigi. + + function Same_Unit (U1, U2 : Node_Id) return Boolean; + -- Returns True iff U1 and U2 represent the same library unit. Used for + -- handling of No_Dependence => Unit restriction case. + + function Suppress_Restriction_Message (N : Node_Id) return Boolean; + -- N is the node for a possible restriction violation message, but + -- the message is to be suppressed if this is an internal file and + -- this file is not the main unit. + + ------------------- + -- Abort_Allowed -- + ------------------- + + function Abort_Allowed return Boolean is + begin + if Restrictions.Set (No_Abort_Statements) + and then Restrictions.Set (Max_Asynchronous_Select_Nesting) + and then Restrictions.Value (Max_Asynchronous_Select_Nesting) = 0 + then + return False; + else + return True; + end if; + end Abort_Allowed; + + ------------------------- + -- Check_Compiler_Unit -- + ------------------------- + + procedure Check_Compiler_Unit (N : Node_Id) is + begin + if Is_Compiler_Unit (Get_Source_Unit (N)) then + Error_Msg_N ("use of construct not allowed in compiler", N); + end if; + end Check_Compiler_Unit; + + ------------------------------------ + -- Check_Elaboration_Code_Allowed -- + ------------------------------------ + + procedure Check_Elaboration_Code_Allowed (N : Node_Id) is + begin + Check_Restriction (No_Elaboration_Code, N); + end Check_Elaboration_Code_Allowed; + + ----------------------------------------- + -- Check_Implicit_Dynamic_Code_Allowed -- + ----------------------------------------- + + procedure Check_Implicit_Dynamic_Code_Allowed (N : Node_Id) is + begin + Check_Restriction (No_Implicit_Dynamic_Code, N); + end Check_Implicit_Dynamic_Code_Allowed; + + ---------------------------------- + -- Check_No_Implicit_Heap_Alloc -- + ---------------------------------- + + procedure Check_No_Implicit_Heap_Alloc (N : Node_Id) is + begin + Check_Restriction (No_Implicit_Heap_Allocations, N); + end Check_No_Implicit_Heap_Alloc; + + --------------------------- + -- Check_Restricted_Unit -- + --------------------------- + + procedure Check_Restricted_Unit (U : Unit_Name_Type; N : Node_Id) is + begin + if Suppress_Restriction_Message (N) then + return; + + elsif Is_Spec_Name (U) then + declare + Fnam : constant File_Name_Type := + Get_File_Name (U, Subunit => False); + + begin + -- Get file name + + Get_Name_String (Fnam); + + -- Nothing to do if name not at least 5 characters long ending + -- in .ads or .adb extension, which we strip. + + if Name_Len < 5 + or else (Name_Buffer (Name_Len - 3 .. Name_Len) /= ".ads" + and then + Name_Buffer (Name_Len - 4 .. Name_Len) /= ".adb") + then + return; + end if; + + -- Strip extension and pad to eight characters + + Name_Len := Name_Len - 4; + while Name_Len < 8 loop + Name_Len := Name_Len + 1; + Name_Buffer (Name_Len) := ' '; + end loop; + + -- If predefined unit, check the list of restricted units + + if Is_Predefined_File_Name (Fnam) then + for J in Unit_Array'Range loop + if Name_Len = 8 + and then Name_Buffer (1 .. 8) = Unit_Array (J).Filenm + then + Check_Restriction (Unit_Array (J).Res_Id, N); + end if; + end loop; + + -- If not predefied unit, then one special check still remains. + -- GNAT.Current_Exception is not allowed if we have restriction + -- No_Exception_Propagation active. + + else + if Name_Buffer (1 .. 8) = "g-curexc" then + Check_Restriction (No_Exception_Propagation, N); + end if; + end if; + end; + end if; + end Check_Restricted_Unit; + + ----------------------- + -- Check_Restriction -- + ----------------------- + + procedure Check_Restriction + (R : Restriction_Id; + N : Node_Id; + V : Uint := Uint_Minus_1) + is + Rimage : constant String := Restriction_Id'Image (R); + + VV : Integer; + -- V converted to integer form. If V is greater than Integer'Last, + -- it is reset to minus 1 (unknown value). + + procedure Update_Restrictions (Info : in out Restrictions_Info); + -- Update violation information in Info.Violated and Info.Count + + ------------------------- + -- Update_Restrictions -- + ------------------------- + + procedure Update_Restrictions (Info : in out Restrictions_Info) is + begin + -- If not violated, set as violated now + + if not Info.Violated (R) then + Info.Violated (R) := True; + + if R in All_Parameter_Restrictions then + if VV < 0 then + Info.Unknown (R) := True; + Info.Count (R) := 1; + else + Info.Count (R) := VV; + end if; + end if; + + -- Otherwise if violated already and a parameter restriction, + -- update count by maximizing or summing depending on restriction. + + elsif R in All_Parameter_Restrictions then + + -- If new value is unknown, result is unknown + + if VV < 0 then + Info.Unknown (R) := True; + + -- If checked by maximization, do maximization + + elsif R in Checked_Max_Parameter_Restrictions then + Info.Count (R) := Integer'Max (Info.Count (R), VV); + + -- If checked by adding, do add, checking for overflow + + elsif R in Checked_Add_Parameter_Restrictions then + declare + pragma Unsuppress (Overflow_Check); + begin + Info.Count (R) := Info.Count (R) + VV; + exception + when Constraint_Error => + Info.Count (R) := Integer'Last; + Info.Unknown (R) := True; + end; + + -- Should not be able to come here, known counts should only + -- occur for restrictions that are Checked_max or Checked_Sum. + + else + raise Program_Error; + end if; + end if; + end Update_Restrictions; + + -- Start of processing for Check_Restriction + + begin + if UI_Is_In_Int_Range (V) then + VV := Integer (UI_To_Int (V)); + else + VV := -1; + end if; + + -- Count can only be specified in the checked val parameter case + + pragma Assert (VV < 0 or else R in Checked_Val_Parameter_Restrictions); + + -- Nothing to do if value of zero specified for parameter restriction + + if VV = 0 then + return; + end if; + + -- Update current restrictions + + Update_Restrictions (Restrictions); + + -- If in main extended unit, update main restrictions as well + + if Current_Sem_Unit = Main_Unit + or else In_Extended_Main_Source_Unit (N) + then + Update_Restrictions (Main_Restrictions); + end if; + + -- Nothing to do if restriction message suppressed + + if Suppress_Restriction_Message (N) then + null; + + -- If restriction not set, nothing to do + + elsif not Restrictions.Set (R) then + null; + + -- Here if restriction set, check for violation (either this is a + -- Boolean restriction, or a parameter restriction with a value of + -- zero and an unknown count, or a parameter restriction with a + -- known value that exceeds the restriction count). + + elsif R in All_Boolean_Restrictions + or else (Restrictions.Unknown (R) + and then Restrictions.Value (R) = 0) + or else Restrictions.Count (R) > Restrictions.Value (R) + then + Error_Msg_Sloc := Restrictions_Loc (R); + + -- If we have a location for the Restrictions pragma, output it + + if Error_Msg_Sloc > No_Location + or else Error_Msg_Sloc = System_Location + then + if Restriction_Warnings (R) then + Restriction_Msg ("|violation of restriction %#?", Rimage, N); + else + Restriction_Msg ("|violation of restriction %#", Rimage, N); + end if; + + -- Otherwise we have the case of an implicit restriction + -- (e.g. a restriction implicitly set by another pragma) + + else + Restriction_Msg + ("|violation of implicit restriction %", Rimage, N); + end if; + end if; + end Check_Restriction; + + ------------------------------------- + -- Check_Restriction_No_Dependence -- + ------------------------------------- + + procedure Check_Restriction_No_Dependence (U : Node_Id; Err : Node_Id) is + DU : Node_Id; + + begin + for J in No_Dependence.First .. No_Dependence.Last loop + DU := No_Dependence.Table (J).Unit; + + if Same_Unit (U, DU) then + Error_Msg_Sloc := Sloc (DU); + Error_Msg_Node_1 := DU; + + if No_Dependence.Table (J).Warn then + Error_Msg + ("?violation of restriction `No_Dependence '='> &`#", + Sloc (Err)); + else + Error_Msg + ("|violation of restriction `No_Dependence '='> &`#", + Sloc (Err)); + end if; + + return; + end if; + end loop; + end Check_Restriction_No_Dependence; + + ---------------------------------------- + -- Cunit_Boolean_Restrictions_Restore -- + ---------------------------------------- + + procedure Cunit_Boolean_Restrictions_Restore + (R : Save_Cunit_Boolean_Restrictions) + is + begin + for J in Cunit_Boolean_Restrictions loop + Restrictions.Set (J) := R (J); + end loop; + end Cunit_Boolean_Restrictions_Restore; + + ------------------------------------- + -- Cunit_Boolean_Restrictions_Save -- + ------------------------------------- + + function Cunit_Boolean_Restrictions_Save + return Save_Cunit_Boolean_Restrictions + is + R : Save_Cunit_Boolean_Restrictions; + + begin + for J in Cunit_Boolean_Restrictions loop + R (J) := Restrictions.Set (J); + Restrictions.Set (J) := False; + end loop; + + return R; + end Cunit_Boolean_Restrictions_Save; + + ------------------------ + -- Get_Restriction_Id -- + ------------------------ + + function Get_Restriction_Id + (N : Name_Id) return Restriction_Id + is + begin + Get_Name_String (N); + Set_Casing (All_Upper_Case); + + for J in All_Restrictions loop + declare + S : constant String := Restriction_Id'Image (J); + begin + if S = Name_Buffer (1 .. Name_Len) then + return J; + end if; + end; + end loop; + + return Not_A_Restriction_Id; + end Get_Restriction_Id; + + ------------------------------- + -- No_Exception_Handlers_Set -- + ------------------------------- + + function No_Exception_Handlers_Set return Boolean is + begin + return (No_Run_Time_Mode or else Configurable_Run_Time_Mode) + and then (Restrictions.Set (No_Exception_Handlers) + or else + Restrictions.Set (No_Exception_Propagation)); + end No_Exception_Handlers_Set; + + ---------------------------------- + -- Process_Restriction_Synonyms -- + ---------------------------------- + + -- Note: body of this function must be coordinated with list of + -- renaming declarations in System.Rident. + + function Process_Restriction_Synonyms (N : Node_Id) return Name_Id + is + Old_Name : constant Name_Id := Chars (N); + New_Name : Name_Id; + + begin + case Old_Name is + when Name_Boolean_Entry_Barriers => + New_Name := Name_Simple_Barriers; + + when Name_Max_Entry_Queue_Depth => + New_Name := Name_Max_Entry_Queue_Length; + + when Name_No_Dynamic_Interrupts => + New_Name := Name_No_Dynamic_Attachment; + + when Name_No_Requeue => + New_Name := Name_No_Requeue_Statements; + + when Name_No_Task_Attributes => + New_Name := Name_No_Task_Attributes_Package; + + when others => + return Old_Name; + end case; + + if Warn_On_Obsolescent_Feature then + Error_Msg_Name_1 := Old_Name; + Error_Msg_N ("restriction identifier % is obsolescent?", N); + Error_Msg_Name_1 := New_Name; + Error_Msg_N ("|use restriction identifier % instead", N); + end if; + + return New_Name; + end Process_Restriction_Synonyms; + + ------------------------ + -- Restricted_Profile -- + ------------------------ + + function Restricted_Profile return Boolean is + begin + if Restricted_Profile_Cached then + return Restricted_Profile_Result; + + else + Restricted_Profile_Result := True; + Restricted_Profile_Cached := True; + + declare + R : Restriction_Flags renames Profile_Info (Restricted).Set; + V : Restriction_Values renames Profile_Info (Restricted).Value; + begin + for J in R'Range loop + if R (J) + and then (Restrictions.Set (J) = False + or else Restriction_Warnings (J) + or else + (J in All_Parameter_Restrictions + and then Restrictions.Value (J) > V (J))) + then + Restricted_Profile_Result := False; + exit; + end if; + end loop; + + return Restricted_Profile_Result; + end; + end if; + end Restricted_Profile; + + ------------------------ + -- Restriction_Active -- + ------------------------ + + function Restriction_Active (R : All_Restrictions) return Boolean is + begin + return Restrictions.Set (R) and then not Restriction_Warnings (R); + end Restriction_Active; + + --------------------- + -- Restriction_Msg -- + --------------------- + + procedure Restriction_Msg (Msg : String; R : String; N : Node_Id) is + B : String (1 .. Msg'Length + 2 * R'Length + 1); + P : Natural := 1; + + begin + Name_Buffer (1 .. R'Last) := R; + Name_Len := R'Length; + Set_Casing (Identifier_Casing (Get_Source_File_Index (Sloc (N)))); + + P := 0; + for J in Msg'Range loop + if Msg (J) = '%' then + P := P + 1; + B (P) := '`'; + + -- Put characters of image in message, quoting upper case letters + + for J in 1 .. Name_Len loop + if Name_Buffer (J) in 'A' .. 'Z' then + P := P + 1; + B (P) := '''; + end if; + + P := P + 1; + B (P) := Name_Buffer (J); + end loop; + + P := P + 1; + B (P) := '`'; + + else + P := P + 1; + B (P) := Msg (J); + end if; + end loop; + + Error_Msg_N (B (1 .. P), N); + end Restriction_Msg; + + --------------- + -- Same_Unit -- + --------------- + + function Same_Unit (U1, U2 : Node_Id) return Boolean is + begin + if Nkind (U1) = N_Identifier then + return Nkind (U2) = N_Identifier and then Chars (U1) = Chars (U2); + + elsif Nkind (U2) = N_Identifier then + return False; + + elsif (Nkind (U1) = N_Selected_Component + or else Nkind (U1) = N_Expanded_Name) + and then + (Nkind (U2) = N_Selected_Component + or else Nkind (U2) = N_Expanded_Name) + then + return Same_Unit (Prefix (U1), Prefix (U2)) + and then Same_Unit (Selector_Name (U1), Selector_Name (U2)); + else + return False; + end if; + end Same_Unit; + + ------------------------------ + -- Set_Profile_Restrictions -- + ------------------------------ + + procedure Set_Profile_Restrictions + (P : Profile_Name; + N : Node_Id; + Warn : Boolean) + is + R : Restriction_Flags renames Profile_Info (P).Set; + V : Restriction_Values renames Profile_Info (P).Value; + + begin + for J in R'Range loop + if R (J) then + declare + Already_Restricted : constant Boolean := Restriction_Active (J); + + begin + -- Set the restriction + + if J in All_Boolean_Restrictions then + Set_Restriction (J, N); + else + Set_Restriction (J, N, V (J)); + end if; + + -- Set warning flag, except that we do not set the warning + -- flag if the restriction was already active and this is + -- the warning case. That avoids a warning overriding a real + -- restriction, which should never happen. + + if not (Warn and Already_Restricted) then + Restriction_Warnings (J) := Warn; + end if; + end; + end if; + end loop; + end Set_Profile_Restrictions; + + --------------------- + -- Set_Restriction -- + --------------------- + + -- Case of Boolean restriction + + procedure Set_Restriction + (R : All_Boolean_Restrictions; + N : Node_Id) + is + begin + -- Restriction No_Elaboration_Code must be enforced on a unit by unit + -- basis. Hence, we avoid setting the restriction when processing an + -- unit which is not the main one being compiled (or its corresponding + -- spec). It can happen, for example, when processing an inlined body + -- (the package containing the inlined subprogram is analyzed, + -- including its pragma Restrictions). + + -- This seems like a very nasty kludge??? This is not the only per unit + -- restriction why is this treated specially ??? + + if R = No_Elaboration_Code + and then Current_Sem_Unit /= Main_Unit + and then Cunit (Current_Sem_Unit) /= Library_Unit (Cunit (Main_Unit)) + then + return; + end if; + + Restrictions.Set (R) := True; + + if Restricted_Profile_Cached and Restricted_Profile_Result then + null; + else + Restricted_Profile_Cached := False; + end if; + + -- Set location, but preserve location of system + -- restriction for nice error msg with run time name + + if Restrictions_Loc (R) /= System_Location then + Restrictions_Loc (R) := Sloc (N); + end if; + + -- Record the restriction if we are in the main unit, or in the extended + -- main unit. The reason that we test separately for Main_Unit is that + -- gnat.adc is processed with Current_Sem_Unit = Main_Unit, but nodes in + -- gnat.adc do not appear to be in the extended main source unit (they + -- probably should do ???) + + if Current_Sem_Unit = Main_Unit + or else In_Extended_Main_Source_Unit (N) + then + if not Restriction_Warnings (R) then + Main_Restrictions.Set (R) := True; + end if; + end if; + end Set_Restriction; + + -- Case of parameter restriction + + procedure Set_Restriction + (R : All_Parameter_Restrictions; + N : Node_Id; + V : Integer) + is + begin + if Restricted_Profile_Cached and Restricted_Profile_Result then + null; + else + Restricted_Profile_Cached := False; + end if; + + if Restrictions.Set (R) then + if V < Restrictions.Value (R) then + Restrictions.Value (R) := V; + Restrictions_Loc (R) := Sloc (N); + end if; + + else + Restrictions.Set (R) := True; + Restrictions.Value (R) := V; + Restrictions_Loc (R) := Sloc (N); + end if; + + -- Record the restriction if we are in the main unit, + -- or in the extended main unit. The reason that we + -- test separately for Main_Unit is that gnat.adc is + -- processed with Current_Sem_Unit = Main_Unit, but + -- nodes in gnat.adc do not appear to be the extended + -- main source unit (they probably should do ???) + + if Current_Sem_Unit = Main_Unit + or else In_Extended_Main_Source_Unit (N) + then + if Main_Restrictions.Set (R) then + if V < Main_Restrictions.Value (R) then + Main_Restrictions.Value (R) := V; + end if; + + elsif not Restriction_Warnings (R) then + Main_Restrictions.Set (R) := True; + Main_Restrictions.Value (R) := V; + end if; + end if; + end Set_Restriction; + + ----------------------------------- + -- Set_Restriction_No_Dependence -- + ----------------------------------- + + procedure Set_Restriction_No_Dependence + (Unit : Node_Id; + Warn : Boolean) + is + begin + -- Loop to check for duplicate entry + + for J in No_Dependence.First .. No_Dependence.Last loop + + -- Case of entry already in table + + if Same_Unit (Unit, No_Dependence.Table (J).Unit) then + + -- Error has precedence over warning + + if not Warn then + No_Dependence.Table (J).Warn := False; + end if; + + return; + end if; + end loop; + + -- Entry is not currently in table + + No_Dependence.Append ((Unit, Warn)); + end Set_Restriction_No_Dependence; + + ---------------------------------- + -- Suppress_Restriction_Message -- + ---------------------------------- + + function Suppress_Restriction_Message (N : Node_Id) return Boolean is + begin + -- We only output messages for the extended main source unit + + if In_Extended_Main_Source_Unit (N) then + return False; + + -- If loaded by rtsfind, then suppress message + + elsif Sloc (N) <= No_Location then + return True; + + -- Otherwise suppress message if internal file + + else + return Is_Internal_File_Name (Unit_File_Name (Get_Source_Unit (N))); + end if; + end Suppress_Restriction_Message; + + --------------------- + -- Tasking_Allowed -- + --------------------- + + function Tasking_Allowed return Boolean is + begin + return not Restrictions.Set (No_Tasking) + and then (not Restrictions.Set (Max_Tasks) + or else Restrictions.Value (Max_Tasks) > 0); + end Tasking_Allowed; + +end Restrict; |