-- --
-- B o d y --
-- --
--- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2013, 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- --
with Elists;
with Errout; use Errout;
with Exp_CG;
+with Exp_Ch6; use Exp_Ch6;
with Fmap;
with Fname; use Fname;
with Fname.UF; use Fname.UF;
with Sem_Elim;
with Sem_Eval;
with Sem_Type;
+with Set_Targ;
with Sinfo; use Sinfo;
with Sinput.L; use Sinput.L;
with Snames;
-- Called when we are not generating code, to check if -gnatR was requested
-- and if so, explain that we will not be honoring the request.
- procedure Check_Library_Items;
- -- For debugging -- checks the behavior of Walk_Library_Items
- pragma Warnings (Off, Check_Library_Items);
- -- In case the call below is commented out
-
----------------------------
-- Adjust_Global_Switches --
----------------------------
procedure Adjust_Global_Switches is
begin
- -- Debug flag -gnatd.I is a synonym for Generate_SCIL and requires code
- -- generation.
+ -- -gnatd.M enables Relaxed_RM_Semantics
- if Debug_Flag_Dot_II
- and then Operating_Mode = Generate_Code
- then
- Generate_SCIL := True;
+ if Debug_Flag_Dot_MM then
+ Relaxed_RM_Semantics := True;
end if;
-- Disable CodePeer_Mode in Check_Syntax, since we need front-end
Restrict.Restrictions.Set (Max_Asynchronous_Select_Nesting) := True;
Restrict.Restrictions.Value (Max_Asynchronous_Select_Nesting) := 0;
- -- Suppress overflow, division by zero and access checks since they
- -- are handled implicitly by CodePeer.
+ -- Suppress division by zero and access checks since they are handled
+ -- implicitly by CodePeer.
-- Turn off dynamic elaboration checks: generates inconsistencies in
-- trees between specs compiled as part of a main unit or as part of
-- Enable all other language checks
- Suppress_Options :=
+ Suppress_Options.Suppress :=
(Access_Check => True,
Alignment_Check => True,
Division_Check => True,
Elaboration_Check => True,
- Overflow_Check => True,
others => False);
- Enable_Overflow_Checks := False;
+
Dynamic_Elaboration_Checks := False;
+ -- Set STRICT mode for overflow checks if not set explicitly. This
+ -- prevents suppressing of overflow checks by default, in code down
+ -- below.
+
+ if Suppress_Options.Overflow_Mode_General = Not_Set then
+ Suppress_Options.Overflow_Mode_General := Strict;
+ Suppress_Options.Overflow_Mode_Assertions := Strict;
+ end if;
+
+ -- CodePeer handles division and overflow checks directly, based on
+ -- the marks set by the frontend, hence no special expansion should
+ -- be performed in the frontend for division and overflow checks.
+
+ Backend_Divide_Checks_On_Target := True;
+ Backend_Overflow_Checks_On_Target := True;
+
-- Kill debug of generated code, since it messes up sloc values
Debug_Generated_Code := False;
Force_ALI_Tree_File := True;
Try_Semantics := True;
+
+ -- Make the Ada front-end more liberal so that the compiler will
+ -- allow illegal code that is allowed by other compilers. CodePeer
+ -- is in the business of finding problems, not enforcing rules!
+ -- This is useful when using CodePeer mode with other compilers.
+
+ Relaxed_RM_Semantics := True;
+ end if;
+
+ if Relaxed_RM_Semantics then
+ Overriding_Renamings := True;
+ end if;
+
+ -- Set switches for formal verification mode
+
+ if Debug_Flag_Dot_VV then
+ Formal_Extensions := True;
+ end if;
+
+ -- Enable Alfa_Mode when using -gnatd.F switch
+
+ if Debug_Flag_Dot_FF then
+ Alfa_Mode := True;
+ end if;
+
+ -- Alfa_Mode is also activated by default in the gnat2why executable
+
+ if Alfa_Mode then
+
+ -- Set strict standard interpretation of compiler permissions
+
+ if Debug_Flag_Dot_DD then
+ Strict_Alfa_Mode := True;
+ end if;
+
+ -- Distinguish between the two modes of gnat2why: frame condition
+ -- generation (generation of ALI files) and translation of Why (no
+ -- ALI files generated). This is done with the switch -gnatd.G,
+ -- which activates frame condition mode. The other changes in
+ -- behavior depending on this switch are done in gnat2why directly.
+
+ if Debug_Flag_Dot_GG then
+ Frame_Condition_Mode := True;
+ else
+ Opt.Disable_ALI_File := True;
+ end if;
+
+ -- Turn off inlining, which would confuse formal verification output
+ -- and gain nothing.
+
+ Front_End_Inlining := False;
+ Inline_Active := False;
+
+ -- Disable front-end optimizations, to keep the tree as close to the
+ -- source code as possible, and also to avoid inconsistencies between
+ -- trees when using different optimization switches.
+
+ Optimization_Level := 0;
+
+ -- Enable some restrictions systematically to simplify the generated
+ -- code (and ease analysis). Note that restriction checks are also
+ -- disabled in Alfa mode, see Restrict.Check_Restriction, and user
+ -- specified Restrictions pragmas are ignored, see
+ -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
+
+ Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
+
+ -- Note: at this point we used to suppress various checks, but that
+ -- is not what we want. We need the semantic processing for these
+ -- checks (which will set flags like Do_Overflow_Check, showing the
+ -- points at which potential checks are required semantically). We
+ -- don't want the expansion associated with these checks, but that
+ -- happens anyway because this expansion is simply not done in the
+ -- Alfa version of the expander.
+
+ -- Turn off dynamic elaboration checks: generates inconsistencies in
+ -- trees between specs compiled as part of a main unit or as part of
+ -- a with-clause.
+
+ Dynamic_Elaboration_Checks := False;
+
+ -- Set STRICT mode for overflow checks if not set explicitly. This
+ -- prevents suppressing of overflow checks by default, in code down
+ -- below.
+
+ if Suppress_Options.Overflow_Mode_General = Not_Set then
+ Suppress_Options.Overflow_Mode_General := Strict;
+ Suppress_Options.Overflow_Mode_Assertions := Strict;
+ end if;
+
+ -- Kill debug of generated code, since it messes up sloc values
+
+ Debug_Generated_Code := False;
+
+ -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
+ -- as it is needed for computing effects of subprograms in the formal
+ -- verification backend.
+
+ Xref_Active := True;
+
+ -- Polling mode forced off, since it generates confusing junk
+
+ Polling_Required := False;
+
+ -- Set operating mode to Generate_Code, but full front-end expansion
+ -- is not desirable in Alfa mode, so a light expansion is performed
+ -- instead.
+
+ Operating_Mode := Generate_Code;
+
+ -- Skip call to gigi
+
+ Debug_Flag_HH := True;
+
+ -- Disable Expressions_With_Actions nodes
+
+ -- The gnat2why backend does not deal with Expressions_With_Actions
+ -- in all places (in particular assertions). It is difficult to
+ -- determine in the frontend which cases are allowed, so we disable
+ -- Expressions_With_Actions entirely. Even in the cases where
+ -- gnat2why deals with Expressions_With_Actions, it is easier to
+ -- deal with the original constructs (quantified, conditional and
+ -- case expressions) instead of the rewritten ones.
+
+ Use_Expression_With_Actions := False;
+
+ -- Enable assertions and debug pragmas, since they give valuable
+ -- extra information for formal verification.
+
+ Assertions_Enabled := True;
+ Debug_Pragmas_Enabled := True;
+
+ -- Turn off style check options since we are not interested in any
+ -- front-end warnings when we are getting Alfa output.
+
+ Reset_Style_Check_Options;
+
+ -- Suppress compiler warnings, since what we are interested in here
+ -- is what formal verification can find out.
+
+ Warning_Mode := Suppress;
+
+ -- Suppress the generation of name tables for enumerations, which are
+ -- not needed for formal verification, and fall outside the Alfa
+ -- subset (use of pointers).
+
+ Global_Discard_Names := True;
+
+ -- Suppress the expansion of tagged types and dispatching calls,
+ -- which lead to the generation of non-Alfa code (use of pointers),
+ -- which is more complex to formally verify than the original source.
+
+ Tagged_Type_Expansion := False;
+
end if;
-- Set Configurable_Run_Time mode if system.ads flag set
Ttypes.Target_Strict_Alignment := True;
end if;
+ -- Increase size of allocated entities if debug flag -gnatd.N is set
+
+ if Debug_Flag_Dot_NN then
+ Atree.Num_Extension_Nodes := Atree.Num_Extension_Nodes + 1;
+ end if;
+
-- Disable static allocation of dispatch tables if -gnatd.t or if layout
-- is enabled. The front end's layout phase currently treats types that
-- have discriminant-dependent arrays as not being static even when a
Exception_Mechanism := Back_End_Exceptions;
end if;
- -- Set proper status for overflow checks. We turn on overflow checks if
- -- -gnatp was not specified, and either -gnato is set or the back-end
- -- takes care of overflow checks. Otherwise we suppress overflow checks
- -- by default (since front end checks are expensive).
-
- if not Opt.Suppress_Checks
- and then (Opt.Enable_Overflow_Checks
- or else
- (Targparm.Backend_Divide_Checks_On_Target
- and
- Targparm.Backend_Overflow_Checks_On_Target))
- then
- Suppress_Options (Overflow_Check) := False;
+ -- Set proper status for overflow check mechanism
+
+ -- If already set (by -gnato or above in Alfa or CodePeer mode) then we
+ -- have nothing to do.
+
+ if Opt.Suppress_Options.Overflow_Mode_General /= Not_Set then
+ null;
+
+ -- Otherwise set overflow mode defaults
+
else
- Suppress_Options (Overflow_Check) := True;
+ -- Otherwise set overflow checks off by default
+
+ Suppress_Options.Suppress (Overflow_Check) := True;
+
+ -- Set appropriate default overflow handling mode. Note: at present
+ -- we set STRICT in all three of the following cases. They are
+ -- separated because in the future we may make different choices.
+
+ -- By default set STRICT mode if -gnatg in effect
+
+ if GNAT_Mode then
+ Suppress_Options.Overflow_Mode_General := Strict;
+ Suppress_Options.Overflow_Mode_Assertions := Strict;
+
+ -- If we have backend divide and overflow checks, then by default
+ -- overflow checks are STRICT. Historically this code used to also
+ -- activate overflow checks, although no target currently has these
+ -- flags set, so this was dead code anyway.
+
+ elsif Targparm.Backend_Divide_Checks_On_Target
+ and
+ Targparm.Backend_Overflow_Checks_On_Target
+ then
+ Suppress_Options.Overflow_Mode_General := Strict;
+ Suppress_Options.Overflow_Mode_Assertions := Strict;
+
+ -- Otherwise for now, default is STRICT mode. This may change in the
+ -- future, but for now this is the compatible behavior with previous
+ -- versions of GNAT.
+
+ else
+ Suppress_Options.Overflow_Mode_General := Strict;
+ Suppress_Options.Overflow_Mode_Assertions := Strict;
+ end if;
end if;
+ -- Set default for atomic synchronization. As this synchronization
+ -- between atomic accesses can be expensive, and not typically needed
+ -- on some targets, an optional target parameter can turn the option
+ -- off. Note Atomic Synchronization is implemented as check.
+
+ Suppress_Options.Suppress (Atomic_Synchronization) :=
+ not Atomic_Sync_Default_On_Target;
+
-- Set switch indicating if we can use N_Expression_With_Actions
-- Debug flag -gnatd.X decisively sets usage on
if Debug_Flag_Dot_XX then
Use_Expression_With_Actions := True;
- -- Debug flag -gnatd.Y decisively set usage off
+ -- Debug flag -gnatd.Y decisively sets usage off
elsif Debug_Flag_Dot_YY then
Use_Expression_With_Actions := False;
-- Set switch indicating if back end can handle limited types, and
-- guarantee that no incorrect copies are made (e.g. in the context
- -- of a conditional expression).
+ -- of an if or case expression).
-- Debug flag -gnatd.L decisively sets usage on
Back_End_Handles_Limited_Types := False;
end if;
- -- Set switches for formal verification mode
-
- if Debug_Flag_Dot_FF then
-
- ALFA_Mode := True;
-
- -- Turn off inlining, which would confuse formal verification output
- -- and gain nothing.
-
- Front_End_Inlining := False;
- Inline_Active := False;
-
- -- Disable front-end optimizations, to keep the tree as close to the
- -- source code as possible, and also to avoid inconsistencies between
- -- trees when using different optimization switches.
-
- Optimization_Level := 0;
-
- -- Enable some restrictions systematically to simplify the generated
- -- code (and ease analysis). Note that restriction checks are also
- -- disabled in ALFA mode, see Restrict.Check_Restriction, and user
- -- specified Restrictions pragmas are ignored, see
- -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
-
- Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
-
- -- Suppress all language checks since they are handled implicitly by
- -- the formal verification backend.
- -- Turn off dynamic elaboration checks.
- -- Turn off alignment checks.
- -- Turn off validity checking.
-
- Suppress_Options := (others => True);
- Enable_Overflow_Checks := False;
- Dynamic_Elaboration_Checks := False;
- Reset_Validity_Check_Options;
-
- -- Kill debug of generated code, since it messes up sloc values
-
- Debug_Generated_Code := False;
-
- -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
-
- Xref_Active := True;
-
- -- Polling mode forced off, since it generates confusing junk
-
- Polling_Required := False;
-
- -- Set operating mode to Generate_Code to benefit from full front-end
- -- expansion (e.g. default arguments).
-
- Operating_Mode := Generate_Code;
-
- -- Skip call to gigi
-
- Debug_Flag_HH := True;
+ -- If the inlining level has not been set by the user, compute it from
+ -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
- -- Disable Expressions_With_Actions nodes
- -- The gnat2why backend does not deal with Expressions_With_Actions
- -- in all places (in particular assertions). It is difficult to
- -- determine in the frontend which cases are allowed, so we disable
- -- Expressions_With_Actions entirely. Even in the cases where
- -- gnat2why deals with Expressions_With_Actions, it is easier to
- -- deal with the original constructs (quantified, conditional and
- -- case expressions) instead of the rewritten ones.
-
- Use_Expression_With_Actions := False;
-
- -- Enable assertions and debug pragmas, since they give valuable
- -- extra information for formal verification.
-
- Assertions_Enabled := True;
- Debug_Pragmas_Enabled := True;
-
- -- Turn off style check options since we are not interested in any
- -- front-end warnings when we are getting ALFA output.
-
- Reset_Style_Check_Options;
-
- -- Suppress compiler warnings, since what we are interested in here
- -- is what formal verification can find out.
-
- Warning_Mode := Suppress;
-
- -- Suppress the generation of name tables for enumerations
-
- Global_Discard_Names := True;
+ if Inline_Level = 0 then
+ if Optimization_Level < 3 then
+ Inline_Level := 1;
+ else
+ Inline_Level := 2;
+ end if;
+ end if;
- -- Suppress the expansion of tagged types and dispatching calls
+ -- Finally capture adjusted value of Suppress_Options as the initial
+ -- value for Scope_Suppress, which will be modified as we move from
+ -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
- Tagged_Type_Expansion := False;
- end if;
+ Sem.Scope_Suppress := Opt.Suppress_Options;
end Adjust_Global_Switches;
--------------------
and then not Compilation_Errors
then
Error_Msg_N
- ("package $$ does not require a body?", Main_Unit_Node);
+ ("package $$ does not require a body??", Main_Unit_Node);
Error_Msg_File_1 := Fname;
- Error_Msg_N ("body in file{? will be ignored", Main_Unit_Node);
+ Error_Msg_N ("body in file{ will be ignored??", Main_Unit_Node);
-- Ada 95 cases of a body file present when no body is
-- permitted. This we consider to be an error.
end if;
end Check_Bad_Body;
- -------------------------
- -- Check_Library_Items --
- -------------------------
-
- -- Walk_Library_Items has plenty of assertions, so all we need to do is
- -- call it, just for these assertions, not actually doing anything else.
-
- procedure Check_Library_Items is
-
- procedure Action (Item : Node_Id);
- -- Action passed to Walk_Library_Items to do nothing
-
- ------------
- -- Action --
- ------------
-
- procedure Action (Item : Node_Id) is
- begin
- null;
- end Action;
-
- procedure Walk is new Sem.Walk_Library_Items (Action);
-
- -- Start of processing for Check_Library_Items
-
- begin
- Walk;
- end Check_Library_Items;
-
--------------------
-- Check_Rep_Info --
--------------------
Usage;
end if;
+ -- Generate target dependent output file if requested
+
+ if Target_Dependent_Info_Write then
+ Set_Targ.Write_Target_Dependent_Values;
+ end if;
+
+ -- Call the front end
+
Original_Operating_Mode := Operating_Mode;
Frontend;
Main_Kind := Nkind (Unit (Main_Unit_Node));
Check_Bad_Body;
+ -- In CodePeer mode we always delete old SCIL files before regenerating
+ -- new ones, in case of e.g. errors, and also to remove obsolete scilx
+ -- files generated by CodePeer itself.
+
+ if CodePeer_Mode then
+ Comperr.Delete_SCIL_Files;
+ end if;
+
-- Exit if compilation errors detected
Errout.Finalize (Last_Call => False);
elsif Main_Kind in N_Generic_Renaming_Declaration then
Back_End_Mode := Generate_Object;
- -- It's not an error to generate SCIL for e.g. a spec which has a body
+ -- It is not an error to analyze in CodePeer mode a spec which requires
+ -- a body, in order to generate SCIL for this spec.
elsif CodePeer_Mode then
Back_End_Mode := Generate_Object;
+ -- It is not an error to analyze in Alfa mode a spec which requires a
+ -- body, when the body is not available. During frame condition
+ -- generation, the corresponding ALI file is generated. During
+ -- translation to Why, Why code is generated for the spec.
+
+ elsif Alfa_Mode then
+ if Frame_Condition_Mode then
+ Back_End_Mode := Declarations_Only;
+ else
+ Back_End_Mode := Generate_Object;
+ end if;
+
-- In all other cases (specs which have bodies, generics, and bodies
-- where subunits are missing), we cannot generate code and we generate
-- a warning message. Note that generic instantiations are gone at this
Namet.Lock;
Stringt.Lock;
- -- ???Check_Library_Items under control of a debug flag, because it
- -- currently does not work if the -gnatn switch (back end inlining) is
- -- used.
-
- if Debug_Flag_Dot_WW then
- Check_Library_Items;
- end if;
-
-- Here we call the back end to generate the output code
Generating_Code := True;
Errout.Finalize (Last_Call => True);
Errout.Output_Messages;
List_Rep_Info;
+ List_Inlining_Info;
-- Only write the library if the backend did not generate any error
-- messages. Otherwise signal errors to the driver program so that