[Ada] Diagnostics in Elaboration order v4.0
authorHristian Kirtchev <kirtchev@adacore.com>
Fri, 5 Jul 2019 07:02:08 +0000 (07:02 +0000)
committerPierre-Marie de Rodat <pmderodat@gcc.gnu.org>
Fri, 5 Jul 2019 07:02:08 +0000 (07:02 +0000)
commit9795b20366362d63be058f1e4f3009d6bad79310
treeaba3763d81a519c490994b1fce8918c7e31e31c2
parentdb6261488e4e53e4ac09ec9db50ea2e4a1859377
[Ada] Diagnostics in Elaboration order v4.0

This patch introduces several changes to the new elaboration order
mechanism:

  * The library graph can now discover, store, and organize the various
    cycles it contains.

  * The elaboration order mechanism can now diagnose one or all cycles
    within the library graph. Diagnostics consist of describing the
    reason for the cycle, listing all units comprising the circuit, and
    offering suggestions on how to break the cycle.

The patch also modifies unit ALI to hide all invocation-related data
structures and several implementation-specific types by relocating them
in the body of the unit.

The patch cleans up most children of Bindo by using better names of
routines and formal parameters.

------------
-- Source --
------------

--  a.ads

with B; pragma Elaborate_All (B);
with C; pragma Elaborate_All (C);

package A is
end A;

--  b.ads

package B is
   procedure Force_Body;
end B;

--  b.adb

with D;

package body B is
   procedure Force_Body is null;

   Elab : constant Integer := D.Func;
end B;

--  c.ads

package C is
   procedure Force_Body;
end C;

--  c.adb

with E;

package body C is
   procedure Force_Body is null;
end C;

--  d.ads

package D is
   function Func return Integer;
end D;

--  d.adb

with A;

package body D is
   Local : Integer := 123;

   function Func return Integer is
   begin
      return Local;
   end Func;
end D;

--  e.ads

with A;

package E is
end E;

--  main.adb

with B;

--             Elaborate_All             Elaborate_All               with
--    C spec <--------------- A spec ---------------------> B spec <------ Main
--      ^                      ^  ^                           ^
--      |                      |  |                           |
--  sbb |                      |  |                           | sbb
--      |                      |  |                           |
--    C body -----------> E spec  |       D spec <--------- B body
--               with             |         ^       with      |
--                                |         |                 |
--                                |     sbb |                 |
--                                |         |                 |
--                                +------ D body <------------+
--                                  with           Invocation
--
--  The cycles are
--
--    A spec --> C spec --> E spec --> A spec
--               C body
--
--    A spec --> B spec --> D body --> A spec
--               B body

procedure Main is begin null; end Main;

----------------------------
-- Compilation and output --
----------------------------

$ gnatmake -q main.adb -bargs -d_C -d_N
error: Elaboration circularity detected
info:
info:    Reason:
info:
info:      unit "a (spec)" depends on its own elaboration
info:
info:    Circularity:
info:
info:      unit "a (spec)" has with clause and pragma Elaborate_All for unit
             "b (spec)"
info:      unit "b (body)" is in the closure of pragma Elaborate_All
info:      unit "b (body)" has with clause for unit "d (spec)"
info:      unit "d (body)" is in the closure of pragma Elaborate_All
info:      unit "d (body)" has with clause for unit "a (spec)"
info:
info:    Suggestions:
info:
info:      change pragma Elaborate_All for unit "b (spec)" to Elaborate in unit
             "a (spec)"
info:      remove pragma Elaborate_All for unit "b (spec)" in unit "a (spec)"
info:
error: Elaboration circularity detected
info:
info:    Reason:
info:
info:      unit "a (spec)" depends on its own elaboration
info:
info:    Circularity:
info:
info:      unit "a (spec)" has with clause and pragma Elaborate_All for unit
             "c (spec)"
info:      unit "c (body)" is in the closure of pragma Elaborate_All
info:      unit "c (body)" has with clause for unit "e (spec)"
info:      unit "e (spec)" has with clause for unit "a (spec)"
info:
info:    Suggestions:
info:
info:      change pragma Elaborate_All for unit "c (spec)" to Elaborate in unit
             "a (spec)"
info:      remove pragma Elaborate_All for unit "c (spec)" in unit "a (spec)"
info:
gnatmake: *** bind failed.

2019-07-05  Hristian Kirtchev  <kirtchev@adacore.com>

gcc/ada/

* ali.adb: Relocate types Invocation_Construct_Record,
Invocation_Relation_Record, and Invocation_Signature_Record to
the body of ALI.  Relocate tables Invocation_Constructs,
Invocation_Relations, and Invocation_Signatures to the body of
ALI.  Remove type Body_Placement_Codes.  Add new types
Declaration_Placement_Codes, and
Invocation_Graph_Encoding_Codes.  Update the literals of type
Invocation_Graph_Line_Codes.
(Add_Invocation_Construct): Update the parameter profile. Add an
invocation construct built from all attributes provided.
(Add_Invocation_Relation): Update the parameter profile. Add an
invocation relation built from all attributes provided.
(Body_Placement): New routine.
(Body_Placement_Kind_To_Code, Code_To_Body_Placement_Kind):
Removed.
(Code_To_Declaration_Placement_Kind,
Code_To_Invocation_Graph_Encoding_Kind, Column,
Declaration_Placement_Kind_To_Code, Extra,
For_Each_Invocation_Construct, For_Each_Invocation_Relation,
Invocation_Graph_Encoding,
Invocation_Graph_Encoding_Kind_To_Code, Invoker, Kind, Line,
Locations, Name): New routine.
(Scan_Invocation_Construct_Line): Reimplement the scanning
mechanism.
(Scan_Invocation_Graph_Attributes_Line): New routine.
(Scan_Invocation_Graph_Line): Use a case statement to dispatch.
(Scan_Invocation_Relation_Line): Reimplement the scanning
mechanism.
(Scope): New routine.
(Set_Invocation_Graph_Encoding, Signature, Spec_Placement,
Target): New routine.
* ali.ads: Add new type Invocation_Graph_Encoding_Kind.  Add
component Invocation_Graph_Encoding to type Unit_Record.
Relocate various types and data structures to the body of ALI.
(Add_Invocation_Construct, Add_Invocation_Relation): Update the
parameter profile.
(Body_Placement): New routine.
(Body_Placement_Kind_To_Code, Code_To_Body_Placement_Kind):
Removed.
(Code_To_Declaration_Placement_Kind,
Code_To_Invocation_Graph_Encoding_Kind, Column,
Declaration_Placement_Kind_To_Code, Extra,
For_Each_Invocation_Construct, For_Each_Invocation_Relation,
Invocation_Graph_Encoding,
Invocation_Graph_Encoding_Kind_To_Code, Invoker, Kind, Line,
Locations, Name, Scope, Set_Invocation_Graph_Encoding,
Signature, Spec_Placement, Target): New routine.
* bindo.adb: Add with clause for Binde.  Add with and use
clauses for Debug.  Update the documentation.  Add new switches.
(Find_Elaboration_Order): Dispatch to the proper elaboration
mechanism.
* bindo-augmentors.adb:
Remove with and use clauses for GNAT and GNAT.Sets.  Remove
membership set VS.  Update the parameter profiles of most
routines to use better parameter names.  Update the
implementation of most routine to use the new parameter names.
Remove various redundant assertions.
* bindo-builders.adb: Use better names for instantiated data
structures. Update all references to these names.  Update the
parameter profiles of most routines to use better parameter
names.  Update the implementation of most routine to use the new
parameter names.
(Build_Library_Graph): Update the parameter profile. Update the
call to Create.
(Create_Vertex): Reimplemented.
(Declaration_Placement_Vertex): New routine.
* bindo-builders.ads (Build_Library_Graph): Update the parameter
profile and comment on usage.
* bindo-diagnostics.adb: Almost a new unit.
* bindo-diagnostics.ads: Add a use clause for
Bindo.Graphs.Invocation_Graphs.  Remove package
Cycle_Diagnostics.
(Diagnose_Circularities): New routine.
* bindo-elaborators.adb: Remove the with and use clauses for
Binderr and GNAT.Sets.  Remove the use clause for
Bindo.Diagnostics.Cycle_Diagnostics.  Remove membership set VS.
Update the parameter profiles of most routines to use better
parameter names.  Update the implementation of most routine to
use the new parameter names.  (Elaborate_Units_Common): Update
the parameter profile. Pass an infication to the library graph
builder whether the dynamic model is in effect.
(Elaborate_Units_Dynamic, Elaborate_Units_Static): Use
Diagnose_Circularities to provide diagnostics.
(Update_Successor): Use routine In_Same_Component to determine
whether the predecessor and successor reside in different
components.
* bindo-graphs.adb: Add with and use clauses for Butil, Debug,
Output, and Bindo.Writers.  Remove with and use clauses for
GNAT.Lists.  Update the parameter profiles of most routines to
use better parameter names.  Update the implementation of most
routine to use the new parameter names.  Remove various
redundant assertions.  Remove doubly linked list EL.  Add new
type Precedence_Kind.
(Add_Cycle): New routine.
(Add_Vertex): Update the parameter profile. Update the creation
of vertex attributes.
(Add_Vertex_And_Complement, Body_Vertex, Column,
Complementary_Vertex, Copy_Cycle_Path, Cycle_Kind_Of): New
routines.
(Destroy_Invocation_Graph_Edge, Destroy_Library_Graph_Cycle,
Destroy_Library_Graph_Edge, Extra, File_Name,
Find_All_Cycles_Through_Vertex, Find_All_Cycles_With_Edge,
Find_Cycles, Find_First_Lower_Precedence_Cycle,
Get_LGC_Attributes, Has_Next, Hash_Library_Graph_Cycle,
Hash_Library_Graph_Cycle_Attributes, Highest_Precedence_Cycle,
Highest_Precedence_Edge, In_Same_Component, Insert_And_Sort,
Invocation_Edge_Count, Invocation_Graph_Encoding,
Is_Cycle_Initiating_Edge, Is_Cyclic_Edge,
Is_Cyclic_Elaborate_All_Edge, Is_Cyclic_Elaborate_Body_Edge,
Is_Cyclic_Elaborate_Edge, Is_Cyclic_Forced_Edge,
Is_Cyclic_Invocation_Edge, Is_Cyclic_With_Edge,
Is_Dynamically_Elaborated, Is_Elaborate_All_Edge,
Is_Elaborate_Body_Edge, Is_Elaborate_Edge: New routines.
(Is_Existing_Predecessor_Successor_Relation): Removed.
(Is_Forced_Edge, Is_Invocation_Edge, Is_Recorded_Cycle,
Is_Recorded_Edge, Is_With_Edge, Iterate_Edges_Of_Cycle, Kind,
Length): New routine.
(Lib_Vertex): Removed.
(Line, Links_Vertices_In_Same_Component,
Maximum_Invocation_Edge_Count, Next, Normalize_And_Add_Cycle,
Normalize_Cycle_Path, Number_Of_Cycles, Path, Precedence,
Remove_Vertex_And_Complement, Sequence_Next_Cycle): New routines.
(Sequence_Next_IGE_Id): Renamed to Sequence_Next_Edge.
(Sequence_Next_IGV_Id): Renamed to Sequence_Next_Vertex.
(Sequence_Next_LGE_Id): Renamed to Sequence_Next_Edge.
(Sequence_Next_LGV_Id): Renamed to Sequence_Next_Vertex.
(Set_Is_Existing_Predecessor_Successor_Relation): Removed.
(Set_Is_Recorded_Cycle, Set_Is_Recorded_Edge,
Set_LGC_Attributes, Spec_Vertex, Trace_Cycle, Trace_Edge,
Trace_Eol, Trace_Vertex): New routines.
* bindo-graphs.ads: Add with and use clauses for Types and
GNAT.Lists.  Update the parameter profiles of most routines to
use better parameter names.  Update the implementation of most
routine to use the new parameter names.  Add the new
instantiated data structures IGE_Lists, IGV_Sets, LGC_Lists,
LGE_Lists, LGE_Sets, LGV_Sets, and RC_Sets.  Add new type
Library_Graph_Cycle_Id along with an empty and initial value.
Remove component Lib_Vertex and add new components Body_Vertex
and Spec_Vertex to type Invocation_Graph_Vertex_Attributes.  Add
new type Library_Graph_Cycle_Kind.  Add new iterators
All_Cycle_Iterator and Edges_Of_Cycle_Iterator.  Add new type
Library_Graph_Cycle_Attributes.  Add new components
Cycle_Attributes, Cycles, and Dynamically_Elaborated to type
Library_Graph_Attributes.
(Body_Vertex, Column, Destroy_Invocation_Graph_Edge,
Destroy_Library_Graph_Cycle_Attributes,
Destroy_Library_Graph_Edge, Extra, File_Name, Find_Cycles,
Has_Elaborate_All_Cycle, Has_Next, Hash_Library_Graph_Cycle,
Hash_Library_Graph_Cycle_Attributes, Highest_Precedence_Cycle,
In_Same_Component, Invocation_Edge_Count,
Invocation_Graph_Encoding, Is_Dynamically_Elaborated,
Is_Elaborate_All_Edge, Is_Elaborate_Body_Edge,
Is_Elaborate_Edge, Is_Forced_Edge, Is_Invocation_Edge,
Is_With_Edge, Iterate_All_Cycles, Iterate_Edges_Of_Cycle, Kind):
New routines.
(Length, Lib_Vertex, (Line, Next, Number_Of_Cycles, Present,
Same_Library_Graph_Cycle_Attributes, Spec_Vertex): New routines.
* bindo-units.adb (File_Name, Invocation_Graph_Encoding): New
routines.
* bindo-units.ads: Add new instantiated data structure
Unit_Sets.
(File_Name, Invocation_Graph_Encoding): New routine.
* bindo-validators.adb: Remove with and use clauses for GNAT and
GNAT.Sets.  Remove membership set US.  Update the parameter
profiles of most routines to use better parameter names.  Update
the implementation of most routine to use the new parameter
names.
(Validate_Cycle, Validate_Cycle_Path, Validate_Cycles,
Validate_Invocation_Graph_Vertex): Remove the validation of
component Lib_Vertex. Add the validation of components
Body_Vertex and Spec_Vertex.
(Write_Error): New routine.
* bindo-validators.ads (Validate_Cycles): New routine.
* bindo-writers.adb: Update the parameter profiles of most
routines to use better parameter names.  Update the
implementation of most routine to use the new parameter names.
(Write_Cycle, Write_Cyclic_Edge, Write_Cycles): New routines.
(Write_Invocation_Graph_Vertex): Remove the output of component
Lib_Vertex. Add the output of components Body_Vertex and
Spec_Vertex.
* bindo-writers.ads (Write_Cycles): New routine.
* debug.adb: Use binder switches -d_C and -d_P, add
documentation on their usage.
* gnatbind.adb: Remove with and use clauses for Binde.  Delegate
the choice of elaboration mechanism to Bindo.
* lib-writ.adb (Column, Extra, Invoker, Kind, Line, Locations,
Name, Placement, Scope, Signature, Target): Removed.
(Write_Invocation_Graph): Moved at the top level.
(Write_Invocation_Graph_Attributes): New routine.
(Write_Invocation_Relation, Write_Invocation_Signature): Moved
at the top level.
* lib-writ.ads: Add a documentation section on invocation graph
attributes.
* sem_elab.adb (Body_Placement_Of): New routine.
(Declare_Invocation_Construct): Update the call to
Add_Invocation_Construct.
(Declaration_Placement_Of_Node): New routine.
(Get_Invocation_Attributes): Correct the retrieval of the
enclosing subprogram where the postcondition procedure lives.
(Placement_Of, Placement_Of_Node): Removed.
(Record_Invocation_Graph): Record the encoding format used.
(Record_Invocation_Graph_Encoding): New routine.
(Record_Invocation_Relation): Update the call to
Add_Invocation_Relation.
(Spec_Placement_Of): Removed.
* libgnat/g-lists.ads, libgnat/g-lists.adb (Equal): New routine.

From-SVN: r273107
25 files changed:
gcc/ada/ChangeLog
gcc/ada/ali.adb
gcc/ada/ali.ads
gcc/ada/bindo-augmentors.adb
gcc/ada/bindo-builders.adb
gcc/ada/bindo-builders.ads
gcc/ada/bindo-diagnostics.adb
gcc/ada/bindo-diagnostics.ads
gcc/ada/bindo-elaborators.adb
gcc/ada/bindo-graphs.adb
gcc/ada/bindo-graphs.ads
gcc/ada/bindo-units.adb
gcc/ada/bindo-units.ads
gcc/ada/bindo-validators.adb
gcc/ada/bindo-validators.ads
gcc/ada/bindo-writers.adb
gcc/ada/bindo-writers.ads
gcc/ada/bindo.adb
gcc/ada/debug.adb
gcc/ada/gnatbind.adb
gcc/ada/lib-writ.adb
gcc/ada/lib-writ.ads
gcc/ada/libgnat/g-lists.adb
gcc/ada/libgnat/g-lists.ads
gcc/ada/sem_elab.adb