Regarding Range Table

[Jim Blandy]

> >>I think comes_from_line and moved_to_line should be CORE_ADDR's, not
> >>line numbers.  The mapping between source location and code is already
> >>represented elsewhere; we shouldn't mix it in here if we don't have
> >>to.  We should convert them into line numbers when they are output.
> I think either CODE_ADDR or line number  is fine for this information. Since
> HP debug info. format  saves this info. as line number,  it is preferable to
> save this info. as line number  so that additional processing is not required
> for both saving as well as displaying.

Oh --- that's too bad.  Line numbers aren't very precise; what if one
source file #includes another file?  Then the line number isn't
sufficient to actually identify the source location.  (I agree that
it's poor coding practice to #include a file into the midst of a
function, but it does happen.  Perhaps even in certain programs with
which we are all familiar.)

If you've got a CORE_ADDR, on the other hand, we've got functions
which will correctly find the right source file and line number, no
matter what you've done with CPP.

It's true that CORE_ADDRs must be converted to line numbers again on
output, but that isn't critical to overall performance.  We can find
them faster than the user can read them.

Reading them is a bit more troublesome, because this is something that
takes a enough long time for the user to complain about.  Also, it's
not clear that you have the line number table available when you are
reading your critical assignment motion info from the file.

So I think it's okay to leave them as line numbers for now, if you
prefer that.