Fix CInstruction in calculating mem access map.

[sv2518]

I don't know if we should calculate something from the predicates or do you think this is sufficient?

[kaushikcfd]

Thanks for the patch, L(almost)GTM!

I don't know if we should calculate something from the predicates or do you think this is sufficient?

Doing something similar to get_op_map would be better i.e. counting the accesses in the predicates and emitting a warning for the uncounted accesses in CInstruction's predicates.

[inducer]

This ultimately did go in as #765, albeit without the requested safeguards. Not the end of the world, I guess.