+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- E X P _ C H 1 1 --
--- --
--- B o d y --
--- --
--- $Revision: 1.2.10.1 $
--- --
--- 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- --
--- ware Foundation; either version 2, 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 COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- 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 Debug; use Debug;
-with Einfo; use Einfo;
-with Exp_Ch7; use Exp_Ch7;
-with Exp_Util; use Exp_Util;
-with Hostparm; use Hostparm;
-with Inline; use Inline;
-with Lib; use Lib;
-with Namet; use Namet;
-with Nlists; use Nlists;
-with Nmake; use Nmake;
-with Opt; use Opt;
-with Rtsfind; use Rtsfind;
-with Restrict; use Restrict;
-with Sem; use Sem;
-with Sem_Ch5; use Sem_Ch5;
-with Sem_Ch8; use Sem_Ch8;
-with Sem_Res; use Sem_Res;
-with Sem_Util; use Sem_Util;
-with Sinfo; use Sinfo;
-with Sinput; use Sinput;
-with Snames; use Snames;
-with Stand; use Stand;
-with Stringt; use Stringt;
-with Targparm; use Targparm;
-with Tbuild; use Tbuild;
-with Uintp; use Uintp;
-with Uname; use Uname;
-
-package body Exp_Ch11 is
-
- SD_List : List_Id;
- -- This list gathers the values SDn'Unrestricted_Access used to
- -- construct the unit exception table. It is set to Empty_List if
- -- there are no subprogram descriptors.
-
- -----------------------
- -- Local Subprograms --
- -----------------------
-
- procedure Expand_Exception_Handler_Tables (HSS : Node_Id);
- -- Subsidiary procedure called by Expand_Exception_Handlers if zero
- -- cost exception handling is installed for this target. Replaces the
- -- exception handler structure with appropriate labeled code and tables
- -- that allow the zero cost exception handling circuits to find the
- -- correct handler (see unit Ada.Exceptions for details).
-
- procedure Generate_Subprogram_Descriptor
- (N : Node_Id;
- Loc : Source_Ptr;
- Spec : Entity_Id;
- Slist : List_Id);
- -- Procedure called to generate a subprogram descriptor. N is the
- -- subprogram body node or, in the case of an imported subprogram, is
- -- Empty, and Spec is the entity of the sunprogram. For details of the
- -- required structure, see package System.Exceptions. The generated
- -- subprogram descriptor is appended to Slist. Loc provides the
- -- source location to be used for the generated descriptor.
-
- ---------------------------
- -- Expand_At_End_Handler --
- ---------------------------
-
- -- For a handled statement sequence that has a cleanup (At_End_Proc
- -- field set), an exception handler of the following form is required:
-
- -- exception
- -- when all others =>
- -- cleanup call
- -- raise;
-
- -- Note: this exception handler is treated rather specially by
- -- subsequent expansion in two respects:
-
- -- The normal call to Undefer_Abort is omitted
- -- The raise call does not do Defer_Abort
-
- -- This is because the current tasking code seems to assume that
- -- the call to the cleanup routine that is made from an exception
- -- handler for the abort signal is called with aborts deferred.
-
- procedure Expand_At_End_Handler (HSS : Node_Id; Block : Node_Id) is
- Clean : constant Entity_Id := Entity (At_End_Proc (HSS));
- Loc : constant Source_Ptr := Sloc (Clean);
- Ohandle : Node_Id;
- Stmnts : List_Id;
-
- begin
- pragma Assert (Present (Clean));
- pragma Assert (No (Exception_Handlers (HSS)));
-
- if Restrictions (No_Exception_Handlers) then
- return;
- end if;
-
- if Present (Block) then
- New_Scope (Block);
- end if;
-
- Ohandle :=
- Make_Others_Choice (Loc);
- Set_All_Others (Ohandle);
-
- Stmnts := New_List (
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (Clean, Loc)),
- Make_Raise_Statement (Loc));
-
- Set_Exception_Handlers (HSS, New_List (
- Make_Exception_Handler (Loc,
- Exception_Choices => New_List (Ohandle),
- Statements => Stmnts)));
-
- Analyze_List (Stmnts, Suppress => All_Checks);
- Expand_Exception_Handlers (HSS);
-
- if Present (Block) then
- Pop_Scope;
- end if;
- end Expand_At_End_Handler;
-
- -------------------------------------
- -- Expand_Exception_Handler_Tables --
- -------------------------------------
-
- -- See Ada.Exceptions specification for full details of the data
- -- structures that we need to construct here. As an example of the
- -- transformation that is required, given the structure:
-
- -- declare
- -- {declarations}
- -- ..
- -- begin
- -- {statements-1}
- -- ...
- -- exception
- -- when a | b =>
- -- {statements-2}
- -- ...
- -- when others =>
- -- {statements-3}
- -- ...
- -- end;
-
- -- We transform this into:
-
- -- declare
- -- {declarations}
- -- ...
- -- L1 : label;
- -- L2 : label;
- -- L3 : label;
- -- L4 : Label;
- -- L5 : label;
-
- -- begin
- -- <<L1>>
- -- {statements-1}
- -- <<L2>>
-
- -- exception
-
- -- when a | b =>
- -- <<L3>>
- -- {statements-2}
-
- -- HR2 : constant Handler_Record := (
- -- Lo => L1'Address,
- -- Hi => L2'Address,
- -- Id => a'Identity,
- -- Handler => L5'Address);
-
- -- HR3 : constant Handler_Record := (
- -- Lo => L1'Address,
- -- Hi => L2'Address,
- -- Id => b'Identity,
- -- Handler => L4'Address);
-
- -- when others =>
- -- <<L4>>
- -- {statements-3}
-
- -- HR1 : constant Handler_Record := (
- -- Lo => L1'Address,
- -- Hi => L2'Address,
- -- Id => Others_Id,
- -- Handler => L4'Address);
- -- end;
-
- -- The exception handlers in the transformed version are marked with the
- -- Zero_Cost_Handling flag set, and all gigi does in this case is simply
- -- to put the handler code somewhere. It can optionally be put inline
- -- between the goto L3 and the label <<L3>> (which is why we generate
- -- that goto in the first place).
-
- procedure Expand_Exception_Handler_Tables (HSS : Node_Id) is
- Loc : constant Source_Ptr := Sloc (HSS);
- Handlrs : constant List_Id := Exception_Handlers (HSS);
- Stms : constant List_Id := Statements (HSS);
- Handler : Node_Id;
-
- Hlist : List_Id;
- -- This is the list to which handlers are to be appended. It is
- -- either the list for the enclosing subprogram, or the enclosing
- -- selective accept statement (which will turn into a subprogram
- -- during expansion later on).
-
- L1 : constant Entity_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('L'));
-
- L2 : constant Entity_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('L'));
-
- Lnn : Entity_Id;
- Choice : Node_Id;
- E_Id : Node_Id;
- HR_Ent : Node_Id;
- HL_Ref : Node_Id;
- Item : Node_Id;
-
- Subp_Entity : Entity_Id;
- -- This is the entity for the subprogram (or library level package)
- -- to which the handler record is to be attached for later reference
- -- in a subprogram descriptor for this entity.
-
- procedure Append_To_Stms (N : Node_Id);
- -- Append given statement to the end of the statements of the
- -- handled sequence of statements and analyze it in place.
-
- function Inside_Selective_Accept return Boolean;
- -- This function is called if we are inside the scope of an entry
- -- or task. It checks if the handler is appearing in the context
- -- of a selective accept statement. If so, Hlist is set to
- -- temporarily park the handlers in the N_Accept_Alternative.
- -- node. They will subsequently be moved to the procedure entity
- -- for the procedure built for this alternative. The statements that
- -- follow the Accept within the alternative are not inside the Accept
- -- for purposes of this test, and handlers that may appear within
- -- them belong in the enclosing task procedure.
-
- procedure Set_Hlist;
- -- Sets the handler list corresponding to Subp_Entity
-
- --------------------
- -- Append_To_Stms --
- --------------------
-
- procedure Append_To_Stms (N : Node_Id) is
- begin
- Insert_After_And_Analyze (Last (Stms), N);
- Set_Exception_Junk (N);
- end Append_To_Stms;
-
- -----------------------------
- -- Inside_Selective_Accept --
- -----------------------------
-
- function Inside_Selective_Accept return Boolean is
- Parnt : Node_Id;
- Curr : Node_Id := HSS;
-
- begin
- Parnt := Parent (HSS);
- while Nkind (Parnt) /= N_Compilation_Unit loop
- if Nkind (Parnt) = N_Accept_Alternative
- and then Curr = Accept_Statement (Parnt)
- then
- if Present (Accept_Handler_Records (Parnt)) then
- Hlist := Accept_Handler_Records (Parnt);
- else
- Hlist := New_List;
- Set_Accept_Handler_Records (Parnt, Hlist);
- end if;
-
- return True;
- else
- Curr := Parnt;
- Parnt := Parent (Parnt);
- end if;
- end loop;
-
- return False;
- end Inside_Selective_Accept;
-
- ---------------
- -- Set_Hlist --
- ---------------
-
- procedure Set_Hlist is
- begin
- -- Never try to inline a subprogram with exception handlers
-
- Set_Is_Inlined (Subp_Entity, False);
-
- if Present (Subp_Entity)
- and then Present (Handler_Records (Subp_Entity))
- then
- Hlist := Handler_Records (Subp_Entity);
- else
- Hlist := New_List;
- Set_Handler_Records (Subp_Entity, Hlist);
- end if;
- end Set_Hlist;
-
- -- Start of processing for Expand_Exception_Handler_Tables
-
- begin
- -- Nothing to do if this handler has already been processed
-
- if Zero_Cost_Handling (HSS) then
- return;
- end if;
-
- Set_Zero_Cost_Handling (HSS);
-
- -- Find the parent subprogram or package scope containing this
- -- exception frame. This should always find a real package or
- -- subprogram. If it does not it will stop at Standard, but
- -- this cannot legitimately occur.
-
- -- We only stop at library level packages, for inner packages
- -- we always attach handlers to the containing procedure.
-
- Subp_Entity := Current_Scope;
- Scope_Loop : loop
-
- -- Never need tables expanded inside a generic template
-
- if Is_Generic_Unit (Subp_Entity) then
- return;
-
- -- Stop if we reached containing subprogram. Go to protected
- -- subprogram if there is one defined.
-
- elsif Ekind (Subp_Entity) = E_Function
- or else Ekind (Subp_Entity) = E_Procedure
- then
- if Present (Protected_Body_Subprogram (Subp_Entity)) then
- Subp_Entity := Protected_Body_Subprogram (Subp_Entity);
- end if;
-
- Set_Hlist;
- exit Scope_Loop;
-
- -- Case of within an entry
-
- elsif Is_Entry (Subp_Entity) then
-
- -- Protected entry, use corresponding body subprogram
-
- if Present (Protected_Body_Subprogram (Subp_Entity)) then
- Subp_Entity := Protected_Body_Subprogram (Subp_Entity);
- Set_Hlist;
- exit Scope_Loop;
-
- -- Check if we are within a selective accept alternative
-
- elsif Inside_Selective_Accept then
-
- -- As a side effect, Inside_Selective_Accept set Hlist,
- -- in much the same manner as Set_Hlist, except that
- -- the list involved was the one for the selective accept.
-
- exit Scope_Loop;
- end if;
-
- -- Case of within library level package
-
- elsif Ekind (Subp_Entity) = E_Package
- and then Is_Compilation_Unit (Subp_Entity)
- then
- if Is_Body_Name (Unit_Name (Get_Code_Unit (HSS))) then
- Subp_Entity := Body_Entity (Subp_Entity);
- end if;
-
- Set_Hlist;
- exit Scope_Loop;
-
- -- Task type case
-
- elsif Ekind (Subp_Entity) = E_Task_Type then
-
- -- Check if we are within a selective accept alternative
-
- if Inside_Selective_Accept then
-
- -- As a side effect, Inside_Selective_Accept set Hlist,
- -- in much the same manner as Set_Hlist, except that the
- -- list involved was the one for the selective accept.
-
- exit Scope_Loop;
-
- -- Stop if we reached task type with task body procedure,
- -- use the task body procedure.
-
- elsif Present (Get_Task_Body_Procedure (Subp_Entity)) then
- Subp_Entity := Get_Task_Body_Procedure (Subp_Entity);
- Set_Hlist;
- exit Scope_Loop;
- end if;
- end if;
-
- -- If we fall through, keep looking
-
- Subp_Entity := Scope (Subp_Entity);
- end loop Scope_Loop;
-
- pragma Assert (Subp_Entity /= Standard_Standard);
-
- -- Analyze standard labels
-
- Analyze_Label_Entity (L1);
- Analyze_Label_Entity (L2);
-
- Insert_Before_And_Analyze (First (Stms),
- Make_Label (Loc,
- Identifier => New_Occurrence_Of (L1, Loc)));
- Set_Exception_Junk (First (Stms));
-
- Append_To_Stms (
- Make_Label (Loc,
- Identifier => New_Occurrence_Of (L2, Loc)));
-
- -- Loop through exception handlers
-
- Handler := First_Non_Pragma (Handlrs);
- while Present (Handler) loop
- Set_Zero_Cost_Handling (Handler);
-
- -- Add label at start of handler, and goto at the end
-
- Lnn :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('L'));
-
- Analyze_Label_Entity (Lnn);
-
- Item :=
- Make_Label (Loc,
- Identifier => New_Occurrence_Of (Lnn, Loc));
- Set_Exception_Junk (Item);
- Insert_Before_And_Analyze (First (Statements (Handler)), Item);
-
- -- Loop through choices
-
- Choice := First (Exception_Choices (Handler));
- while Present (Choice) loop
-
- -- Others (or all others) choice
-
- if Nkind (Choice) = N_Others_Choice then
- if All_Others (Choice) then
- E_Id := New_Occurrence_Of (RTE (RE_All_Others_Id), Loc);
- else
- E_Id := New_Occurrence_Of (RTE (RE_Others_Id), Loc);
- end if;
-
- -- Special case of VMS_Exception. Not clear what we will do
- -- eventually here if and when we implement zero cost exceptions
- -- on VMS. But at least for now, don't blow up trying to take
- -- a garbage code address for such an exception.
-
- elsif Is_VMS_Exception (Entity (Choice)) then
- E_Id := New_Occurrence_Of (RTE (RE_Null_Id), Loc);
-
- -- Normal case of specific exception choice
-
- else
- E_Id :=
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Entity (Choice), Loc),
- Attribute_Name => Name_Identity);
- end if;
-
- HR_Ent :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('H'));
-
- HL_Ref :=
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (HR_Ent, Loc),
- Attribute_Name => Name_Unrestricted_Access);
-
- -- Now we need to add the entry for the new handler record to
- -- the list of handler records for the current subprogram.
-
- -- Normally we end up generating the handler records in exactly
- -- the right order. Here right order means innermost first,
- -- since the table will be searched sequentially. Since we
- -- generally expand from outside to inside, the order is just
- -- what we want, and we need to append the new entry to the
- -- end of the list.
-
- -- However, there are exceptions, notably in the case where
- -- a generic body is inserted later on. See for example the
- -- case of ACVC test C37213J, which has the following form:
-
- -- generic package x ... end x;
- -- package body x is
- -- begin
- -- ...
- -- exception (1)
- -- ...
- -- end x;
-
- -- ...
-
- -- declare
- -- package q is new x;
- -- begin
- -- ...
- -- exception (2)
- -- ...
- -- end;
-
- -- In this case, we will expand exception handler (2) first,
- -- since the expansion of (1) is delayed till later when the
- -- generic body is inserted. But (1) belongs before (2) in
- -- the chain.
-
- -- Note that scopes are not totally ordered, because two
- -- scopes can be in parallel blocks, so that it does not
- -- matter what order these entries appear in. An ordering
- -- relation exists if one scope is inside another, and what
- -- we really want is some partial ordering.
-
- -- A simple, not very efficient, but adequate algorithm to
- -- achieve this partial ordering is to search the list for
- -- the first entry containing the given scope, and put the
- -- new entry just before it.
-
- declare
- New_Scop : constant Entity_Id := Current_Scope;
- Ent : Node_Id;
-
- begin
- Ent := First (Hlist);
- loop
- -- If all searched, then we can just put the new
- -- entry at the end of the list (it actually does
- -- not matter where we put it in this case).
-
- if No (Ent) then
- Append_To (Hlist, HL_Ref);
- exit;
-
- -- If the current scope is within the scope of the
- -- entry then insert the entry before to retain the
- -- proper order as per above discussion.
-
- -- Note that for equal entries, we just keep going,
- -- which is fine, the entry will end up at the end
- -- of the list where it belongs.
-
- elsif Scope_Within
- (New_Scop, Scope (Entity (Prefix (Ent))))
- then
- Insert_Before (Ent, HL_Ref);
- exit;
-
- -- Otherwise keep looking
-
- else
- Next (Ent);
- end if;
- end loop;
- end;
-
- Item :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => HR_Ent,
- Constant_Present => True,
- Aliased_Present => True,
- Object_Definition =>
- New_Occurrence_Of (RTE (RE_Handler_Record), Loc),
-
- Expression =>
- Make_Aggregate (Loc,
- Expressions => New_List (
- Make_Attribute_Reference (Loc, -- Lo
- Prefix => New_Occurrence_Of (L1, Loc),
- Attribute_Name => Name_Address),
-
- Make_Attribute_Reference (Loc, -- Hi
- Prefix => New_Occurrence_Of (L2, Loc),
- Attribute_Name => Name_Address),
-
- E_Id, -- Id
-
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Lnn, Loc), -- Handler
- Attribute_Name => Name_Address))));
-
- Set_Handler_List_Entry (Item, HL_Ref);
- Set_Exception_Junk (Item);
- Insert_After_And_Analyze (Last (Statements (Handler)), Item);
- Set_Is_Statically_Allocated (HR_Ent);
-
- -- If this is a late insertion (from body instance) it is being
- -- inserted in the component list of an already analyzed aggre-
- -- gate, and must be analyzed explicitly.
-
- Analyze_And_Resolve (HL_Ref, RTE (RE_Handler_Record_Ptr));
-
- Next (Choice);
- end loop;
-
- Next_Non_Pragma (Handler);
- end loop;
- end Expand_Exception_Handler_Tables;
-
- -------------------------------
- -- Expand_Exception_Handlers --
- -------------------------------
-
- procedure Expand_Exception_Handlers (HSS : Node_Id) is
- Handlrs : constant List_Id := Exception_Handlers (HSS);
- Loc : Source_Ptr;
- Handler : Node_Id;
- Others_Choice : Boolean;
- Obj_Decl : Node_Id;
-
- procedure Prepend_Call_To_Handler
- (Proc : RE_Id;
- Args : List_Id := No_List);
- -- Routine to prepend a call to the procedure referenced by Proc at
- -- the start of the handler code for the current Handler.
-
- procedure Prepend_Call_To_Handler
- (Proc : RE_Id;
- Args : List_Id := No_List)
- is
- Call : constant Node_Id :=
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (RTE (Proc), Loc),
- Parameter_Associations => Args);
-
- begin
- Prepend_To (Statements (Handler), Call);
- Analyze (Call, Suppress => All_Checks);
- end Prepend_Call_To_Handler;
-
- -- Start of processing for Expand_Exception_Handlers
-
- begin
- -- Loop through handlers
-
- Handler := First_Non_Pragma (Handlrs);
- while Present (Handler) loop
- Loc := Sloc (Handler);
-
- -- If an exception occurrence is present, then we must declare it
- -- and initialize it from the value stored in the TSD
-
- -- declare
- -- name : Exception_Occurrence;
- --
- -- begin
- -- Save_Occurrence (name, Get_Current_Excep.all)
- -- ...
- -- end;
-
- if Present (Choice_Parameter (Handler)) then
- declare
- Cparm : constant Entity_Id := Choice_Parameter (Handler);
- Clc : constant Source_Ptr := Sloc (Cparm);
- Save : Node_Id;
-
- begin
- Save :=
- Make_Procedure_Call_Statement (Loc,
- Name =>
- New_Occurrence_Of (RTE (RE_Save_Occurrence), Loc),
- Parameter_Associations => New_List (
- New_Occurrence_Of (Cparm, Clc),
- Make_Explicit_Dereference (Loc,
- Make_Function_Call (Loc,
- Name => Make_Explicit_Dereference (Loc,
- New_Occurrence_Of
- (RTE (RE_Get_Current_Excep), Loc))))));
-
- Mark_Rewrite_Insertion (Save);
- Prepend (Save, Statements (Handler));
-
- Obj_Decl :=
- Make_Object_Declaration (Clc,
- Defining_Identifier => Cparm,
- Object_Definition =>
- New_Occurrence_Of
- (RTE (RE_Exception_Occurrence), Clc));
- Set_No_Initialization (Obj_Decl, True);
-
- Rewrite (Handler,
- Make_Exception_Handler (Loc,
- Exception_Choices => Exception_Choices (Handler),
-
- Statements => New_List (
- Make_Block_Statement (Loc,
- Declarations => New_List (Obj_Decl),
- Handled_Statement_Sequence =>
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => Statements (Handler))))));
-
- Analyze_List (Statements (Handler), Suppress => All_Checks);
- end;
- end if;
-
- -- The processing at this point is rather different for the
- -- JVM case, so we completely separate the processing.
-
- -- For the JVM case, we unconditionally call Update_Exception,
- -- passing a call to the intrinsic function Current_Target_Exception
- -- (see JVM version of Ada.Exceptions in 4jexcept.adb for details).
-
- if Hostparm.Java_VM then
- declare
- Arg : Node_Id
- := Make_Function_Call (Loc,
- Name => New_Occurrence_Of
- (RTE (RE_Current_Target_Exception), Loc));
- begin
- Prepend_Call_To_Handler (RE_Update_Exception, New_List (Arg));
- end;
-
- -- For the normal case, we have to worry about the state of abort
- -- deferral. Generally, we defer abort during runtime handling of
- -- exceptions. When control is passed to the handler, then in the
- -- normal case we undefer aborts. In any case this entire handling
- -- is relevant only if aborts are allowed!
-
- elsif Abort_Allowed then
-
- -- There are some special cases in which we do not do the
- -- undefer. In particular a finalization (AT END) handler
- -- wants to operate with aborts still deferred.
-
- -- We also suppress the call if this is the special handler
- -- for Abort_Signal, since if we are aborting, we want to keep
- -- aborts deferred (one abort is enough thank you very much :-)
-
- -- If abort really needs to be deferred the expander must add
- -- this call explicitly, see Exp_Ch9.Expand_N_Asynchronous_Select.
-
- Others_Choice :=
- Nkind (First (Exception_Choices (Handler))) = N_Others_Choice;
-
- if (Others_Choice
- or else Entity (First (Exception_Choices (Handler))) /=
- Stand.Abort_Signal)
- and then not
- (Others_Choice
- and then All_Others (First (Exception_Choices (Handler))))
- and then Abort_Allowed
- then
- Prepend_Call_To_Handler (RE_Abort_Undefer);
- end if;
- end if;
-
- Next_Non_Pragma (Handler);
- end loop;
-
- -- The last step for expanding exception handlers is to expand the
- -- exception tables if zero cost exception handling is active.
-
- if Exception_Mechanism = Front_End_ZCX then
- Expand_Exception_Handler_Tables (HSS);
- end if;
- end Expand_Exception_Handlers;
-
- ------------------------------------
- -- Expand_N_Exception_Declaration --
- ------------------------------------
-
- -- Generates:
- -- exceptE : constant String := "A.B.EXCEP"; -- static data
- -- except : exception_data := (
- -- Handled_By_Other => False,
- -- Lang => 'A',
- -- Name_Length => exceptE'Length
- -- Full_Name => exceptE'Address
- -- HTable_Ptr => null);
-
- -- (protecting test only needed if not at library level)
- --
- -- exceptF : Boolean := True -- static data
- -- if exceptF then
- -- exceptF := False;
- -- Register_Exception (except'Unchecked_Access);
- -- end if;
-
- procedure Expand_N_Exception_Declaration (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Id : constant Entity_Id := Defining_Identifier (N);
- L : List_Id := New_List;
- Flag_Id : Entity_Id;
-
- Name_Exname : constant Name_Id := New_External_Name (Chars (Id), 'E');
- Exname : constant Node_Id :=
- Make_Defining_Identifier (Loc, Name_Exname);
-
- begin
- -- There is no expansion needed when compiling for the JVM since the
- -- JVM has a built-in exception mechanism. See 4jexcept.ads for details.
-
- if Hostparm.Java_VM then
- return;
- end if;
-
- -- Definition of the external name: nam : constant String := "A.B.NAME";
-
- Insert_Action (N,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Exname,
- Constant_Present => True,
- Object_Definition => New_Occurrence_Of (Standard_String, Loc),
- Expression => Make_String_Literal (Loc, Full_Qualified_Name (Id))));
-
- Set_Is_Statically_Allocated (Exname);
-
- -- Create the aggregate list for type Standard.Exception_Type:
- -- Handled_By_Other component: False
-
- Append_To (L, New_Occurrence_Of (Standard_False, Loc));
-
- -- Lang component: 'A'
-
- Append_To (L,
- Make_Character_Literal (Loc, Name_uA, Get_Char_Code ('A')));
-
- -- Name_Length component: Nam'Length
-
- Append_To (L,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Exname, Loc),
- Attribute_Name => Name_Length));
-
- -- Full_Name component: Standard.A_Char!(Nam'Address)
-
- Append_To (L, Unchecked_Convert_To (Standard_A_Char,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Exname, Loc),
- Attribute_Name => Name_Address)));
-
- -- HTable_Ptr component: null
-
- Append_To (L, Make_Null (Loc));
-
- -- Import_Code component: 0
-
- Append_To (L, Make_Integer_Literal (Loc, 0));
-
- Set_Expression (N, Make_Aggregate (Loc, Expressions => L));
- Analyze_And_Resolve (Expression (N), Etype (Id));
-
- -- Register_Exception (except'Unchecked_Access);
-
- if not Restrictions (No_Exception_Handlers) then
- L := New_List (
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (RTE (RE_Register_Exception), Loc),
- Parameter_Associations => New_List (
- Unchecked_Convert_To (RTE (RE_Exception_Data_Ptr),
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Id, Loc),
- Attribute_Name => Name_Unrestricted_Access)))));
-
- Set_Register_Exception_Call (Id, First (L));
-
- if not Is_Library_Level_Entity (Id) then
- Flag_Id := Make_Defining_Identifier (Loc,
- New_External_Name (Chars (Id), 'F'));
-
- Insert_Action (N,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Flag_Id,
- Object_Definition =>
- New_Occurrence_Of (Standard_Boolean, Loc),
- Expression =>
- New_Occurrence_Of (Standard_True, Loc)));
-
- Set_Is_Statically_Allocated (Flag_Id);
-
- Append_To (L,
- Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Flag_Id, Loc),
- Expression => New_Occurrence_Of (Standard_False, Loc)));
-
- Insert_After_And_Analyze (N,
- Make_Implicit_If_Statement (N,
- Condition => New_Occurrence_Of (Flag_Id, Loc),
- Then_Statements => L));
-
- else
- Insert_List_After_And_Analyze (N, L);
- end if;
- end if;
-
- end Expand_N_Exception_Declaration;
-
- ---------------------------------------------
- -- Expand_N_Handled_Sequence_Of_Statements --
- ---------------------------------------------
-
- procedure Expand_N_Handled_Sequence_Of_Statements (N : Node_Id) is
- begin
- if Present (Exception_Handlers (N)) then
- Expand_Exception_Handlers (N);
- end if;
-
- -- The following code needs comments ???
-
- if Nkind (Parent (N)) /= N_Package_Body
- and then Nkind (Parent (N)) /= N_Accept_Statement
- and then not Delay_Cleanups (Current_Scope)
- then
- Expand_Cleanup_Actions (Parent (N));
- else
- Set_First_Real_Statement (N, First (Statements (N)));
- end if;
-
- end Expand_N_Handled_Sequence_Of_Statements;
-
- -------------------------------------
- -- Expand_N_Raise_Constraint_Error --
- -------------------------------------
-
- -- The only processing required is to adjust the condition to deal
- -- with the C/Fortran boolean case. This may well not be necessary,
- -- as all such conditions are generated by the expander and probably
- -- are all standard boolean, but who knows what strange optimization
- -- in future may require this adjustment!
-
- procedure Expand_N_Raise_Constraint_Error (N : Node_Id) is
- begin
- Adjust_Condition (Condition (N));
- end Expand_N_Raise_Constraint_Error;
-
- ----------------------------------
- -- Expand_N_Raise_Program_Error --
- ----------------------------------
-
- -- The only processing required is to adjust the condition to deal
- -- with the C/Fortran boolean case. This may well not be necessary,
- -- as all such conditions are generated by the expander and probably
- -- are all standard boolean, but who knows what strange optimization
- -- in future may require this adjustment!
-
- procedure Expand_N_Raise_Program_Error (N : Node_Id) is
- begin
- Adjust_Condition (Condition (N));
- end Expand_N_Raise_Program_Error;
-
- ------------------------------
- -- Expand_N_Raise_Statement --
- ------------------------------
-
- procedure Expand_N_Raise_Statement (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Ehand : Node_Id;
- E : Entity_Id;
- Str : String_Id;
-
- begin
- -- There is no expansion needed for statement "raise <exception>;" when
- -- compiling for the JVM since the JVM has a built-in exception
- -- mechanism. However we need the keep the expansion for "raise;"
- -- statements. See 4jexcept.ads for details.
-
- if Present (Name (N)) and then Hostparm.Java_VM then
- return;
- end if;
-
- -- Convert explicit raise of Program_Error, Constraint_Error, and
- -- Storage_Error into the corresponding raise node (in No_Run_Time
- -- mode all other raises will get normal expansion and be disallowed,
- -- but this is also faster in all modes).
-
- if Present (Name (N)) and then Nkind (Name (N)) = N_Identifier then
- if Entity (Name (N)) = Standard_Program_Error then
- Rewrite (N, Make_Raise_Program_Error (Loc));
- Analyze (N);
- return;
-
- elsif Entity (Name (N)) = Standard_Constraint_Error then
- Rewrite (N, Make_Raise_Constraint_Error (Loc));
- Analyze (N);
- return;
-
- elsif Entity (Name (N)) = Standard_Storage_Error then
- Rewrite (N, Make_Raise_Storage_Error (Loc));
- Analyze (N);
- return;
- end if;
- end if;
-
- -- Case of name present, in this case we expand raise name to
-
- -- Raise_Exception (name'Identity, location_string);
-
- -- where location_string identifies the file/line of the raise
-
- if Present (Name (N)) then
- declare
- Id : Entity_Id := Entity (Name (N));
-
- begin
- Build_Location_String (Loc);
-
- -- Build a C compatible string in case of no exception handlers,
- -- since this is what the last chance handler is expecting.
-
- if Restrictions (No_Exception_Handlers) then
- -- Generate a C null message when Global_Discard_Names is True
- -- or when Debug_Flag_NN is set.
-
- if Global_Discard_Names or else Debug_Flag_NN then
- Name_Buffer (1) := ASCII.NUL;
- Name_Len := 1;
- else
- Name_Len := Name_Len + 1;
- end if;
-
- -- Do not generate the message when Global_Discard_Names is True
- -- or when Debug_Flag_NN is set.
-
- elsif Global_Discard_Names or else Debug_Flag_NN then
- Name_Len := 0;
- end if;
-
- Str := String_From_Name_Buffer;
-
- -- For VMS exceptions, convert the raise into a call to
- -- lib$stop so it will be handled by __gnat_error_handler.
-
- if Is_VMS_Exception (Id) then
- declare
- Excep_Image : String_Id;
- Cond : Node_Id;
-
- begin
- if Present (Interface_Name (Id)) then
- Excep_Image := Strval (Interface_Name (Id));
- else
- Get_Name_String (Chars (Id));
- Set_All_Upper_Case;
- Excep_Image := String_From_Name_Buffer;
- end if;
-
- if Exception_Code (Id) /= No_Uint then
- Cond :=
- Make_Integer_Literal (Loc, Exception_Code (Id));
- else
- Cond :=
- Unchecked_Convert_To (Standard_Integer,
- Make_Function_Call (Loc,
- Name => New_Occurrence_Of
- (RTE (RE_Import_Value), Loc),
- Parameter_Associations => New_List
- (Make_String_Literal (Loc,
- Strval => Excep_Image))));
- end if;
-
- Rewrite (N,
- Make_Procedure_Call_Statement (Loc,
- Name =>
- New_Occurrence_Of (RTE (RE_Lib_Stop), Loc),
- Parameter_Associations => New_List (Cond)));
- Analyze_And_Resolve (Cond, Standard_Integer);
- end;
-
- -- Not VMS exception case, convert raise to call to the
- -- Raise_Exception routine.
-
- else
- Rewrite (N,
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (RTE (RE_Raise_Exception), Loc),
- Parameter_Associations => New_List (
- Make_Attribute_Reference (Loc,
- Prefix => Name (N),
- Attribute_Name => Name_Identity),
- Make_String_Literal (Loc,
- Strval => Str))));
- end if;
- end;
-
- -- Case of no name present (reraise). We rewrite the raise to:
-
- -- Reraise_Occurrence_Always (EO);
-
- -- where EO is the current exception occurrence. If the current handler
- -- does not have a choice parameter specification, then we provide one.
-
- else
- -- Find innermost enclosing exception handler (there must be one,
- -- since the semantics has already verified that this raise statement
- -- is valid, and a raise with no arguments is only permitted in the
- -- context of an exception handler.
-
- Ehand := Parent (N);
- while Nkind (Ehand) /= N_Exception_Handler loop
- Ehand := Parent (Ehand);
- end loop;
-
- -- Make exception choice parameter if none present. Note that we do
- -- not need to put the entity on the entity chain, since no one will
- -- be referencing this entity by normal visibility methods.
-
- if No (Choice_Parameter (Ehand)) then
- E := Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
- Set_Choice_Parameter (Ehand, E);
- Set_Ekind (E, E_Variable);
- Set_Etype (E, RTE (RE_Exception_Occurrence));
- Set_Scope (E, Current_Scope);
- end if;
-
- -- Now rewrite the raise as a call to Reraise. A special case arises
- -- if this raise statement occurs in the context of a handler for
- -- all others (i.e. an at end handler). in this case we avoid
- -- the call to defer abort, cleanup routines are expected to be
- -- called in this case with aborts deferred.
-
- declare
- Ech : constant Node_Id := First (Exception_Choices (Ehand));
- Ent : Entity_Id;
-
- begin
- if Nkind (Ech) = N_Others_Choice
- and then All_Others (Ech)
- then
- Ent := RTE (RE_Reraise_Occurrence_No_Defer);
- else
- Ent := RTE (RE_Reraise_Occurrence_Always);
- end if;
-
- Rewrite (N,
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (Ent, Loc),
- Parameter_Associations => New_List (
- New_Occurrence_Of (Choice_Parameter (Ehand), Loc))));
- end;
- end if;
-
- Analyze (N);
- end Expand_N_Raise_Statement;
-
- ----------------------------------
- -- Expand_N_Raise_Storage_Error --
- ----------------------------------
-
- -- The only processing required is to adjust the condition to deal
- -- with the C/Fortran boolean case. This may well not be necessary,
- -- as all such conditions are generated by the expander and probably
- -- are all standard boolean, but who knows what strange optimization
- -- in future may require this adjustment!
-
- procedure Expand_N_Raise_Storage_Error (N : Node_Id) is
- begin
- Adjust_Condition (Condition (N));
- end Expand_N_Raise_Storage_Error;
-
- ------------------------------
- -- Expand_N_Subprogram_Info --
- ------------------------------
-
- procedure Expand_N_Subprogram_Info (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
-
- begin
- -- For now, we replace an Expand_N_Subprogram_Info node with an
- -- attribute reference that gives the address of the procedure.
- -- This is because gigi does not yet recognize this node, and
- -- for the initial targets, this is the right value anyway.
-
- Rewrite (N,
- Make_Attribute_Reference (Loc,
- Prefix => Identifier (N),
- Attribute_Name => Name_Code_Address));
-
- Analyze_And_Resolve (N, RTE (RE_Code_Loc));
- end Expand_N_Subprogram_Info;
-
- ------------------------------------
- -- Generate_Subprogram_Descriptor --
- ------------------------------------
-
- procedure Generate_Subprogram_Descriptor
- (N : Node_Id;
- Loc : Source_Ptr;
- Spec : Entity_Id;
- Slist : List_Id)
- is
- Code : Node_Id;
- Ent : Entity_Id;
- Decl : Node_Id;
- Dtyp : Entity_Id;
- Numh : Nat;
- Sdes : Node_Id;
- Hrc : List_Id;
-
- begin
- if Exception_Mechanism /= Front_End_ZCX then
- return;
- end if;
-
- -- Suppress descriptor if we are not generating code. This happens
- -- in the case of a -gnatc -gnatt compilation where we force generics
- -- to be generated, but we still don't want exception tables.
-
- if Operating_Mode /= Generate_Code then
- return;
- end if;
-
- -- Suppress descriptor if we are in No_Exceptions restrictions mode,
- -- since we can never propagate exceptions in any case in this mode.
- -- The same consideration applies for No_Exception_Handlers (which
- -- is also set in No_Run_Time mode).
-
- if Restrictions (No_Exceptions)
- or Restrictions (No_Exception_Handlers)
- then
- return;
- end if;
-
- -- Suppress descriptor if we are inside a generic. There are two
- -- ways that we can tell that, depending on what is going on. If
- -- we are actually inside the processing for a generic right now,
- -- then Expander_Active will be reset. If we are outside the
- -- generic, then we will see the generic entity.
-
- if not Expander_Active then
- return;
- end if;
-
- -- Suppress descriptor is subprogram is marked as eliminated, for
- -- example if this is a subprogram created to analyze a default
- -- expression with potential side effects. Ditto if it is nested
- -- within an eliminated subprogram, for example a cleanup action.
-
- declare
- Scop : Entity_Id;
-
- begin
- Scop := Spec;
- while Scop /= Standard_Standard loop
- if Ekind (Scop) = E_Generic_Procedure
- or else
- Ekind (Scop) = E_Generic_Function
- or else
- Ekind (Scop) = E_Generic_Package
- or else
- Is_Eliminated (Scop)
- then
- return;
- end if;
-
- Scop := Scope (Scop);
- end loop;
- end;
-
- -- Suppress descriptor for original protected subprogram (we will
- -- be called again later to generate the descriptor for the actual
- -- protected body subprogram.) This does not apply to barrier
- -- functions which are there own protected subprogram.
-
- if Is_Subprogram (Spec)
- and then Present (Protected_Body_Subprogram (Spec))
- and then Protected_Body_Subprogram (Spec) /= Spec
- then
- return;
- end if;
-
- -- Suppress descriptors for packages unless they have at least one
- -- handler. The binder will generate the dummy (no handler) descriptors
- -- for elaboration procedures. We can't do it here, because we don't
- -- know if an elaboration routine does in fact exist.
-
- -- If there is at least one handler for the package spec or body
- -- then most certainly an elaboration routine must exist, so we
- -- can safely reference it.
-
- if (Nkind (N) = N_Package_Declaration
- or else
- Nkind (N) = N_Package_Body)
- and then No (Handler_Records (Spec))
- then
- return;
- end if;
-
- -- Suppress all subprogram descriptors for the file System.Exceptions.
- -- We similarly suppress subprogram descriptors for Ada.Exceptions.
- -- These are all init_proc's for types which cannot raise exceptions.
- -- The reason this is done is that otherwise we get embarassing
- -- elaboration dependencies.
-
- Get_Name_String (Unit_File_Name (Current_Sem_Unit));
-
- if Name_Buffer (1 .. 12) = "s-except.ads"
- or else
- Name_Buffer (1 .. 12) = "a-except.ads"
- then
- return;
- end if;
-
- -- Similarly, we need to suppress entries for System.Standard_Library,
- -- since otherwise we get elaboration circularities. Again, this would
- -- better be done with a Suppress_Initialization pragma :-)
-
- if Name_Buffer (1 .. 11) = "s-stalib.ad" then
- return;
- end if;
-
- -- For now, also suppress entries for s-stoele because we have
- -- some kind of unexplained error there ???
-
- if Name_Buffer (1 .. 11) = "s-stoele.ad" then
- return;
- end if;
-
- -- And also for g-htable, because it cannot raise exceptions,
- -- and generates some kind of elaboration order problem.
-
- if Name_Buffer (1 .. 11) = "g-htable.ad" then
- return;
- end if;
-
- -- Suppress subprogram descriptor if already generated. This happens
- -- in the case of late generation from Delay_Subprogram_Descriptors
- -- beging set (where there is more than one instantiation in the list)
-
- if Has_Subprogram_Descriptor (Spec) then
- return;
- else
- Set_Has_Subprogram_Descriptor (Spec);
- end if;
-
- -- Never generate descriptors for inlined bodies
-
- if Analyzing_Inlined_Bodies then
- return;
- end if;
-
- -- Here we definitely are going to generate a subprogram descriptor
-
- declare
- Hnum : Nat := Homonym_Number (Spec);
-
- begin
- if Hnum = 1 then
- Hnum := 0;
- end if;
-
- Ent :=
- Make_Defining_Identifier (Loc,
- Chars => New_External_Name (Chars (Spec), "SD", Hnum));
- end;
-
- if No (Handler_Records (Spec)) then
- Hrc := Empty_List;
- Numh := 0;
- else
- Hrc := Handler_Records (Spec);
- Numh := List_Length (Hrc);
- end if;
-
- New_Scope (Spec);
-
- -- We need a static subtype for the declaration of the subprogram
- -- descriptor. For the case of 0-3 handlers we can use one of the
- -- predefined subtypes in System.Exceptions. For more handlers,
- -- we build our own subtype here.
-
- case Numh is
- when 0 =>
- Dtyp := RTE (RE_Subprogram_Descriptor_0);
-
- when 1 =>
- Dtyp := RTE (RE_Subprogram_Descriptor_1);
-
- when 2 =>
- Dtyp := RTE (RE_Subprogram_Descriptor_2);
-
- when 3 =>
- Dtyp := RTE (RE_Subprogram_Descriptor_3);
-
- when others =>
- Dtyp :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('T'));
-
- -- Set the constructed type as global, since we will be
- -- referencing the object that is of this type globally
-
- Set_Is_Statically_Allocated (Dtyp);
-
- Decl :=
- Make_Subtype_Declaration (Loc,
- Defining_Identifier => Dtyp,
- Subtype_Indication =>
- Make_Subtype_Indication (Loc,
- Subtype_Mark =>
- New_Occurrence_Of (RTE (RE_Subprogram_Descriptor), Loc),
- Constraint =>
- Make_Index_Or_Discriminant_Constraint (Loc,
- Constraints => New_List (
- Make_Integer_Literal (Loc, Numh)))));
-
- Append (Decl, Slist);
-
- -- We analyze the descriptor for the subprogram and package
- -- case, but not for the imported subprogram case (it will
- -- be analyzed when the freeze entity actions are analyzed.
-
- if Present (N) then
- Analyze (Decl);
- end if;
-
- Set_Exception_Junk (Decl);
- end case;
-
- -- Prepare the code address entry for the table entry. For the normal
- -- case of being within a procedure, this is simply:
-
- -- P'Code_Address
-
- -- where P is the procedure, but for the package case, it is
-
- -- P'Elab_Body'Code_Address
- -- P'Elab_Spec'Code_Address
-
- -- for the body and spec respectively. Note that we do our own
- -- analysis of these attribute references, because we know in this
- -- case that the prefix of ELab_Body/Spec is a visible package,
- -- which can be referenced directly instead of using the general
- -- case expansion for these attributes.
-
- if Ekind (Spec) = E_Package then
- Code :=
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Spec, Loc),
- Attribute_Name => Name_Elab_Spec);
- Set_Etype (Code, Standard_Void_Type);
- Set_Analyzed (Code);
-
- elsif Ekind (Spec) = E_Package_Body then
- Code :=
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Spec_Entity (Spec), Loc),
- Attribute_Name => Name_Elab_Body);
- Set_Etype (Code, Standard_Void_Type);
- Set_Analyzed (Code);
-
- else
- Code := New_Occurrence_Of (Spec, Loc);
- end if;
-
- Code :=
- Make_Attribute_Reference (Loc,
- Prefix => Code,
- Attribute_Name => Name_Code_Address);
-
- Set_Etype (Code, RTE (RE_Address));
- Set_Analyzed (Code);
-
- -- Now we can build the subprogram descriptor
-
- Sdes :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent,
- Constant_Present => True,
- Aliased_Present => True,
- Object_Definition => New_Occurrence_Of (Dtyp, Loc),
-
- Expression =>
- Make_Aggregate (Loc,
- Expressions => New_List (
- Make_Integer_Literal (Loc, Numh), -- Num_Handlers
-
- Code, -- Code
-
--- temp code ???
-
--- Make_Subprogram_Info (Loc, -- Subprogram_Info
--- Identifier =>
--- New_Occurrence_Of (Spec, Loc)),
-
- New_Copy_Tree (Code),
-
- Make_Aggregate (Loc, -- Handler_Records
- Expressions => Hrc))));
-
- Set_Exception_Junk (Sdes);
- Set_Is_Subprogram_Descriptor (Sdes);
-
- Append (Sdes, Slist);
-
- -- We analyze the descriptor for the subprogram and package case,
- -- but not for the imported subprogram case (it will be analyzed
- -- when the freeze entity actions are analyzed.
-
- if Present (N) then
- Analyze (Sdes);
- end if;
-
- -- We can now pop the scope used for analyzing the descriptor
-
- Pop_Scope;
-
- -- We need to set the descriptor as statically allocated, since
- -- it will be referenced from the unit exception table.
-
- Set_Is_Statically_Allocated (Ent);
-
- -- Append the resulting descriptor to the list. We do this only
- -- if we are in the main unit. You might think that we could
- -- simply skip generating the descriptors completely if we are
- -- not in the main unit, but in fact this is not the case, since
- -- we have problems with inconsistent serial numbers for internal
- -- names if we do this.
-
- if In_Extended_Main_Code_Unit (Spec) then
- Append_To (SD_List,
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ent, Loc),
- Attribute_Name => Name_Unrestricted_Access));
-
- Unit_Exception_Table_Present := True;
- end if;
-
- end Generate_Subprogram_Descriptor;
-
- ------------------------------------------------------------
- -- Generate_Subprogram_Descriptor_For_Imported_Subprogram --
- ------------------------------------------------------------
-
- procedure Generate_Subprogram_Descriptor_For_Imported_Subprogram
- (Spec : Entity_Id;
- Slist : List_Id)
- is
- begin
- Generate_Subprogram_Descriptor (Empty, Sloc (Spec), Spec, Slist);
- end Generate_Subprogram_Descriptor_For_Imported_Subprogram;
-
- ------------------------------------------------
- -- Generate_Subprogram_Descriptor_For_Package --
- ------------------------------------------------
-
- procedure Generate_Subprogram_Descriptor_For_Package
- (N : Node_Id;
- Spec : Entity_Id)
- is
- Adecl : Node_Id;
-
- begin
- Adecl := Aux_Decls_Node (Parent (N));
-
- if No (Actions (Adecl)) then
- Set_Actions (Adecl, New_List);
- end if;
-
- Generate_Subprogram_Descriptor (N, Sloc (N), Spec, Actions (Adecl));
- end Generate_Subprogram_Descriptor_For_Package;
-
- ---------------------------------------------------
- -- Generate_Subprogram_Descriptor_For_Subprogram --
- ---------------------------------------------------
-
- procedure Generate_Subprogram_Descriptor_For_Subprogram
- (N : Node_Id;
- Spec : Entity_Id)
- is
- HSS : constant Node_Id := Handled_Statement_Sequence (N);
-
- begin
- if No (Exception_Handlers (HSS)) then
- Generate_Subprogram_Descriptor
- (N, Sloc (N), Spec, Statements (HSS));
- else
- Generate_Subprogram_Descriptor
- (N, Sloc (N), Spec, Statements (Last (Exception_Handlers (HSS))));
- end if;
- end Generate_Subprogram_Descriptor_For_Subprogram;
-
- -----------------------------------
- -- Generate_Unit_Exception_Table --
- -----------------------------------
-
- -- The only remaining thing to generate here is to generate the
- -- reference to the subprogram descriptor chain. See Ada.Exceptions
- -- for details of required data structures.
-
- procedure Generate_Unit_Exception_Table is
- Loc : constant Source_Ptr := No_Location;
- Num : Nat;
- Decl : Node_Id;
- Ent : Entity_Id;
- Next_Ent : Entity_Id;
- Stent : Entity_Id;
-
- begin
- -- Nothing to be done if zero length exceptions not active
-
- if Exception_Mechanism /= Front_End_ZCX then
- return;
- end if;
-
- -- Remove any entries from SD_List that correspond to eliminated
- -- subprograms.
-
- Ent := First (SD_List);
- while Present (Ent) loop
- Next_Ent := Next (Ent);
- if Is_Eliminated (Scope (Entity (Prefix (Ent)))) then
- Remove (Ent); -- After this, there is no Next (Ent) anymore
- end if;
-
- Ent := Next_Ent;
- end loop;
-
- -- Nothing to do if no unit exception table present.
- -- An empty table can result from subprogram elimination,
- -- in such a case, eliminate the exception table itself.
-
- if Is_Empty_List (SD_List) then
- Unit_Exception_Table_Present := False;
- return;
- end if;
-
- -- Do not generate table in a generic
-
- if Inside_A_Generic then
- return;
- end if;
-
- -- Generate the unit exception table
-
- -- subtype Tnn is Subprogram_Descriptors_Record (Num);
- -- __gnat_unitname__SDP : aliased constant Tnn :=
- -- Num,
- -- (sub1'unrestricted_access,
- -- sub2'unrestricted_access,
- -- ...
- -- subNum'unrestricted_access));
-
- Num := List_Length (SD_List);
-
- Stent :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('T'));
-
- Insert_Library_Level_Action (
- Make_Subtype_Declaration (Loc,
- Defining_Identifier => Stent,
- Subtype_Indication =>
- Make_Subtype_Indication (Loc,
- Subtype_Mark =>
- New_Occurrence_Of
- (RTE (RE_Subprogram_Descriptors_Record), Loc),
- Constraint =>
- Make_Index_Or_Discriminant_Constraint (Loc,
- Constraints => New_List (
- Make_Integer_Literal (Loc, Num))))));
-
- Set_Is_Statically_Allocated (Stent);
-
- Get_External_Unit_Name_String (Unit_Name (Main_Unit));
- Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
- Name_Buffer (1 .. 7) := "__gnat_";
- Name_Len := Name_Len + 7;
- Add_Str_To_Name_Buffer ("__SDP");
-
- Ent :=
- Make_Defining_Identifier (Loc,
- Chars => Name_Find);
-
- Get_Name_String (Chars (Ent));
- Set_Interface_Name (Ent,
- Make_String_Literal (Loc, Strval => String_From_Name_Buffer));
-
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent,
- Object_Definition => New_Occurrence_Of (Stent, Loc),
- Constant_Present => True,
- Aliased_Present => True,
- Expression =>
- Make_Aggregate (Loc,
- New_List (
- Make_Integer_Literal (Loc, List_Length (SD_List)),
-
- Make_Aggregate (Loc,
- Expressions => SD_List))));
-
- Insert_Library_Level_Action (Decl);
-
- Set_Is_Exported (Ent, True);
- Set_Is_Public (Ent, True);
- Set_Is_Statically_Allocated (Ent, True);
-
- Get_Name_String (Chars (Ent));
- Set_Interface_Name (Ent,
- Make_String_Literal (Loc,
- Strval => String_From_Name_Buffer));
-
- end Generate_Unit_Exception_Table;
-
- ----------------
- -- Initialize --
- ----------------
-
- procedure Initialize is
- begin
- SD_List := Empty_List;
- end Initialize;
-
- ----------------------
- -- Is_Non_Ada_Error --
- ----------------------
-
- function Is_Non_Ada_Error (E : Entity_Id) return Boolean is
- begin
- if not OpenVMS_On_Target then
- return False;
- end if;
-
- Get_Name_String (Chars (E));
-
- -- Note: it is a little irregular for the body of exp_ch11 to know
- -- the details of the encoding scheme for names, but on the other
- -- hand, gigi knows them, and this is for gigi's benefit anyway!
-
- if Name_Buffer (1 .. 30) /= "system__aux_dec__non_ada_error" then
- return False;
- end if;
-
- return True;
- end Is_Non_Ada_Error;
-
- ----------------------------
- -- Remove_Handler_Entries --
- ----------------------------
-
- procedure Remove_Handler_Entries (N : Node_Id) is
- function Check_Handler_Entry (N : Node_Id) return Traverse_Result;
- -- This function checks one node for a possible reference to a
- -- handler entry that must be deleted. it always returns OK.
-
- function Remove_All_Handler_Entries is new
- Traverse_Func (Check_Handler_Entry);
- -- This defines the traversal operation
-
- Discard : Traverse_Result;
-
- function Check_Handler_Entry (N : Node_Id) return Traverse_Result is
- begin
- if Nkind (N) = N_Object_Declaration then
-
- if Present (Handler_List_Entry (N)) then
- Remove (Handler_List_Entry (N));
- Delete_Tree (Handler_List_Entry (N));
- Set_Handler_List_Entry (N, Empty);
-
- elsif Is_Subprogram_Descriptor (N) then
- declare
- SDN : Node_Id;
-
- begin
- SDN := First (SD_List);
- while Present (SDN) loop
- if Defining_Identifier (N) = Entity (Prefix (SDN)) then
- Remove (SDN);
- Delete_Tree (SDN);
- exit;
- end if;
-
- Next (SDN);
- end loop;
- end;
- end if;
- end if;
-
- return OK;
- end Check_Handler_Entry;
-
- -- Start of processing for Remove_Handler_Entries
-
- begin
- if Exception_Mechanism = Front_End_ZCX then
- Discard := Remove_All_Handler_Entries (N);
- end if;
- end Remove_Handler_Entries;
-
-end Exp_Ch11;
projects / msp430-gcc.git / blobdiff