Instrument correctly about bisect_ppx HOT 1 CLOSED

Bisect_ppx isn't disciplined about how it places points. Consider:

The point apparently on later in everything is actually on sooner, since that has to be evaluated first. There is no point that would indicate that sooner completed and later was reached. In everything_sequence, both places have a point.

I think the rationale for putting points on sequence expressions was that if an exception occurs in the first, the second is not reached. However, similar statements are true of most constructs in the language that have subexpressions.

Now that we don't have point kinds, we should consider putting points on many more expressions, and doing it correctly.

There may be some challenges, when an expression has the same location as some relevant subexpression. I can't immediately think of an example, however.

I think the instrumenter's mapper will probably need a rewrite to address all expression kinds correctly.

from bisect_ppx.