Commit 2c315ee75e ("BUG/MEDIUM: ebtree: don't set attribute packed
without unaligned access support") addressed alignment issues in
ebtrees in a way that is not really optimal since it will leave holes
in eb32trees for example.
This fix is better in that it restores the packed attribute on ebnode
but enforces proper alignment on the carrying nodes where necessary.
This also has the benefit of closing holes wherever possible and to
align data to the minimally required size.
The only thing it cannot close is the 32-bit hole at the end of ebmbnode
due to the required 64-bit on certain archs but at least it guarantees
that the key correctly points to the end of the node and that there is
never a hole after it.
This is a better fix than the one above and should be backported to
branches where the one above will be backported.
This used to be a minor optimization on ix86 where registers are scarce
and the calling convention not very efficient, but this platform is not
relevant enough anymore to warrant all this dirt in the code for the sake
of saving 1 or 2% of performance. Modern platforms don't use this at all
since their calling convention already defaults to using several registers
so better get rid of this once for all.
And indicate what is required for this (that the pattern is properly
terminated by a zero).
(cherry picked from commit c87c93800ce4045b1053302d99a3cd78321a7ec4)
Sometimes it's very useful to visit duplicates of a same node, but doing
so from the application is not convenient because keys have to be compared,
while all the information is available during the next/prev steps.
Let's introduce a couple of new eb_next_dup/eb_prev_dup functions to visit
only duplicates of the current node and return NULL once it's done. Now we
have all 3 combinations :
- next : returns next node in the tree
- next_dup : returns next dup in the sub-tree
- next_unique : returns next value after skipping dups
(cherry picked from commit 3327b8ae6866f3878322a1a29e70b450226d216d)
Otherwise we end up comparing the byte past the end, resulting
in duplicate values still being inserted into the tree even if
undesired.
This generally has low impact, though it can sometimes cause one new entry
to be added next to an existing one for stick tables, preventing the results
from being merged.
(cherry picked from commit 12e54ac493a91bb02064568f410592c2700d3933)
(from ebtree 6.0.7)
root_right was wrongly initialized first to <root> which is not the same
type, to be later initialized to root->b[EB_RGHT].
Let's simply remove the wrong and useless initialization.
(cherry picked from commit e63a0c2f56369b52c4d00221d83c2c4569605c06)
(from ebtree 6.0.6)
This version is mainly aimed at clarifying the fact that the ebtree license
is LGPL. Some files used to indicate LGPL and other ones GPL, while the goal
clearly is to have it LGPL. A LICENSE file has also been added.
No code is affected, but it's better to have the local tree in sync anyway.
(cherry picked from commit 24dc7cca051f081600fe8232f33e55ed30e88425)
(from ebtree 6.0.6)
Care has been taken not to make the code bigger (it even got smaller
due to a possible simplification).
(cherry picked from commit 7a2c1df646049c7daac52677ec11ed63048cd150)
(from ebtree 6.0.5)
Last bugfix has introduced a de-optimization in the lookup function because
it artificially extended the scope of some local variables, which resulted in
higher stack usage and more numerous moves between stack and registers.
We can reduce that by moving the return code out of the loop, because gcc
notices that it never needs both "troot" and "node" at the same time and
can use the same register for both. Doing so has reduced the code size by
39 bytes for the lookup function alone, and has sensibly reduced the
instruction dependencies caused by data moves.
(cherry picked from commit 59be3cdb96296b65a57aff30cc203269f9a94ebe)
It should be backported to 1.4 if previous ebtree fix is backported.
(from ebtree 6.0.5)
ebmb_lookup() is used by ebst_lookup_len() to lookup a string starting
with a known substring. Since the substring does not necessarily end
with a zero, we must absolutely ensure that the comparison stops at
<len> bytes, otherwise we can end up comparing crap and most often
returning the wrong node in case of multiple matches.
ebim_lookup() was fixed too by resyncing it with ebmb_lookup().
(cherry picked from commit 98eba315aa2c3285181375d312bcb770f058fd2b)
This should be backported to 1.4 though it's not critical there.
This version adds support for prefix-based matching of memory blocks,
as well as some code-size and performance improvements on the generic
code. It provides a prefix insertion and longest match which are
compatible with the rest of the common features (walk, duplicates,
delete, ...). This is typically used for network address matching. The
longest-match code is a bit slower than the original memory block
handling code, so they have not been merged together into generic
code. Still it's possible to perform about 10 million networks lookups
per second in a set of 50000, so this should be enough for most usages.
This version also fixes some bugs in parts that were not used, so there
is no need to backport them.
We needed to upgrade ebtree to v5.0 to support string indexing,
and it was getting very painful to have it split across 2 dirs
and to have to patch it. Now we just have to copy the .c and .h
files to the right place.
