Merging of two small structures with large-arity predicates is slow and memory-intensive

[Joachim Jansen]

Attached file performs merging of two structure that are completely disjunct and have small domains (<10 elements / type). Running the attached file shows that this merging cannot be done with even +3GB of memory, whilst the operation is intuitively simple.

[Bart Bogaerts]

Very large arity -> 8^10 CF atoms

Merge is not very good yet... Many improvements are possible.

[Joachim Jansen]

Suggested solution: detect cases in merge(..) where it is not necessary to iterate over ct/cf tables?

[Broes De Cat]

Additional example: Merging tests/mx/simplemx/autocomplete_speed.idp with a two-valued version of itself takes 80 sec.

[Broes De Cat]

Issue #770 was marked as a duplicate of this issue.