An "augmented tree" is a tree with extra data attached which flows from
the leaves to the root. An "interval tree" is a datastructure of
(potentially-overlapping) intervals where, in addition to inserting and
removing intervals, we can quickly lookup all the intervals which
overlap a given interval.
After describing red-black trees, CLRS explains how it's possible to
implement an interval tree using an augmented red-black tree where the
nodes are ordered by interval start and each node also stores the
maximum interval end for its entire subtree.
Implement the interval tree extension described by CLRS. Iterating over
all overlapping intervals is actually an exercise, so we have to solve
the exercise. The recursive solution has been re-written to use the
parent pointers to avoid needing a stack, similarly to rb_tree_first()
and rb_node_next().
For now, we only implement unsigned intervals, but the core algorithms
are all abstracted to allow other types. There's still some boilerplate,
but it's the best that can be done in C.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22071>
Add a Mesa base style instead of copying the same rules multiple times.
This is especially annoying with foreach macros, where every
.clang-format file maintains it's own incomplete list of the same
macros.
Adding a tree wide .clang-format allows other drivers to derive their
code style from whatever is considered default Mesa style.
Since clang-format doesn't allow us to derive ForEachMacros, driver
specific foreach macros have to be added to the common file.
Having a tree wide clang format should also help (new) contributers with
working oin parts of the tree that don't have their own .clang-format
file. (With regards to code formatting)
Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23275>
Alyssa Rosenzweig
Connor Abbott
Konstantin Seurer
Faith Ekstrand
Eric Engestrom
Yonggang Luo