Mads Kiilerich <madski@unity3d.com> [Tue, 08 Nov 2016 18:37:33 +0100] rev 30439
bdiff: rearrange the "better longest match" code
This is primarily to make the code more managable and prepare for later
changes.
More specific assignments might also be slightly faster, even thought it also
might generate a bit more code.
Mads Kiilerich <madski@unity3d.com> [Tue, 08 Nov 2016 18:37:33 +0100] rev 30438
bdiff: adjust criteria for getting optimal longest match in the A side middle
We prefer matches closer to the middle to balance recursion, as introduced in
f1ca249696ed.
For ranges with uneven length, matches starting exactly in the middle should
have preference. That will be optimal for matches of length 1. We will thus
accept equality in the half check.
For ranges with even length, half was ceil'ed when calculated but we got the
preference for low matches from the 'less than half' check. To get the same
result as before when we also accept equality, floor it. Without that,
test-annotate.t would show some different (still correct but less optimal)
results.
This will change the heuristics. Tests shows a slightly different output - and
sometimes slightly smaller bundles.
The bundle size for 4.0 (hg bundle --base null -r 4.0 x.hg) happens to go from
22804885 to 22803824 bytes - an 0.005% reduction.
Mads Kiilerich <madski@unity3d.com> [Tue, 08 Nov 2016 18:37:33 +0100] rev 30437
tests: explore some bdiff cases