This patch introduces a new cycle detection algorithm which is based on
Tarjan's "Enumeration of the Elementary Circuits of a Directed Graph"
algorithm, with several ideas borrowed from Jonson's "Finding all the
Elementary Circuits of a Directed Graph" algorithm.
No need for a test because the new algorithm improves the performance of
cycle detection only.
2019-07-10 Hristian Kirtchev <kirtchev@adacore.com>
gcc/ada/
* bindo.adb: Update the section on switches.
* bindo-graphs.adb
(Add_Cycle, Add_Vertex_And_Complement): Remove.
(Create): The graph no longer needs a set of recorded cycles
because the cycles are not rediscovered in permuted forms.
(Cycle_End_Vertices): New routine.
(Destroy): The graph no longer needs a set of recorded cycles
because the cycles are not rediscovered in permuted forms.
(Destroy_Library_Graph_Vertex): Move to the library level.
(Find_All_Cycles_Through_Vertex, Find_All_Cycles_With_Edge):
Remove.
(Find_Cycles_From_Successor, Find_Cycles_From_Vertex,
Find_Cycles_In_Component, Has_Elaborate_All_Edge): New routines.
(Insert_And_Sort): Remove.
(Is_Elaborate_Body_Edge): Use predicate
Is_Vertex_With_Elaborate_Body.
(Is_Recorded_Cycle): Remove.
(Is_Vertex_With_Elaborate_Body): New routine.
(Normalize_And_Add_Cycle): Remove.
(Precedence): Rename to xxx_Precedence, where xxx relates to the
input. These versions better reflect the desired input
precedence.
(Record_Cycle): New routine.
(Remove_Vertex_And_Complement, Set_Is_Recorded_Cycle): Remove.
(Trace_xxx): Update all versions to use debug switch -d_t.
(Trace_Component): New routine.
(Trace_Eol): Removed.
(Trace_Vertex): Do not output the component as this information
is already available when the component is traced.
(Unvisit, Visit): New routine.
* bindo-graphs.ads: Add new instance LGV_Lists. Remove instance
RC_Sets. Update the structure of type Library_Graph_Attributes
to remove the set of recorded cycles.
(Destroy_Library_Graph_Vertex): Move to the library level.
* bindo-writers.adb (Write_Component_Vertices): Output
information about the number of vertices.
* debug.adb: Document the use of binder switch -d_t. Update the
use of binder switch -d_T.
From-SVN: r273330
