set_while checks the iterator's current element membership and skips to
the first element with different membership. ie, if the current element
is in the set, then set_while returns the next element *not* in the set,
but if the current is not in the set, then set_while returns the next
element that *is* in the set. Rather handy for dealing with clusters of
set elements.
When using SET_STATIC_INIT, the set size needs to be the same as what
set_new() would create for the same number of bits, otherwise the set
will possibly get resized incorrectly (which is bad news when the array
was allocated using alloca). While this is really a symptom of
set_bits_t not getting the right size, getting weird segfaults is not a
good way to diagnose the problem, and set_bits_t being the wrong size is
just a minor pessimism.
At the low level, only unions can cause a set to grow. Of course, things
get interesting at the higher level when infinite (inverted) sets are
mixed in.
Instead of printing every representable member of an infinite set (ie,
up to element 63 in a set that can hold 64 elements), only those
elements up to one after the last non-member are listed. For example,
{...} - {2 3} -> {0 1 4 ...}
This makes reading (and testing!) infinite sets much easier.
Most of the set ops were always endian-agnostic since they were simply
operating on multiple bits in parallel, but individual element
add/remove/test was very endian-dependent. For the most part, this
didn't matter, but it does matter very much when loading external data
into a set or writing the data out (eg, for PVS).
After seeing set_size and thinking it redundant (thought it returned the
capacity of the set until I checked), I realized set_count would be a
much better name (set_count (node->successors) in qfcc does make much
more sense).
Having set_expand exposed is useful for loading data into a set.
However, it turns out there was a bug in its size calculation in that
when the requested set size was a multiple of SET_BITS (and greater than
the current set size), the new set size one be SET_BITS larger than
requested. There's now some tests for this :)
set_bits_t is now 64 bits for x86_64 machines (in linux, anyway). This gave
qfvis a huge speed boost: from ~815s to ~720s.
Also, expose some of the set internals so custom set operators can be
created.
Getting everything right with an enum proved to be too difficult if not
impossible. Also use better tests for equivalence and intersection.
Many more tests have been added. All pass :)
Also move the ALLOC/FREE macros from qfcc.h to QF/alloc.h (needed to for
set.c).
Both modules are more generally useful than just for qfcc (eg, set
builtins for ruamoko).