bdiff: don't check border condition in loop
This is pretty much a copy of d500ddae7494, just to a different loop.
The condition `p == plast` (`plast == a + len - 1`) was only true on
the final iteration of the loop. So it was wasteful to check for it
on every iteration. We decrease the iteration count by 1 and add an
explicit check for `p == plast` after the loop.
Again, we see modest wins.
From the mozilla-unified repository:
$ perfbdiff -m 3041e4d59df2
! wall 0.035502 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)
! wall 0.030480 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)
$ perfbdiff 0e9928989e9c --alldata --count 100
! wall 4.097394 comb 4.100000 user 4.100000 sys 0.000000 (best of 3)
! wall 3.597798 comb 3.600000 user 3.600000 sys 0.000000 (best of 3)
The 2nd example throws a total of ~3.3GB of data at bdiff. This
change increases the throughput from ~811 MB/s to ~924 MB/s.
#!/bin/sh -e
#
# Build a Mercurial debian package from the current repo
#
# Tested on Jessie (stable as of original script authoring.)
. $(dirname $0)/packagelib.sh
BUILD=1
CLEANUP=1
DISTID=`(lsb_release -is 2> /dev/null | tr '[:upper:]' '[:lower:]') || echo debian`
CODENAME=`lsb_release -cs 2> /dev/null || echo unknown`
DEBFLAGS=-b
while [ "$1" ]; do
case "$1" in
--distid )
shift
DISTID="$1"
shift
;;
--codename )
shift
CODENAME="$1"
shift
;;
--cleanup )
shift
BUILD=
;;
--build )
shift
CLEANUP=
;;
--source-only )
shift
DEBFLAGS=-S
;;
* )
echo "Invalid parameter $1!" 1>&2
exit 1
;;
esac
done
trap "if [ '$CLEANUP' ] ; then rm -r '$PWD/debian' ; fi" EXIT
set -u
if [ ! -d .hg ]; then
echo 'You are not inside a Mercurial repository!' 1>&2
exit 1
fi
gethgversion
debver="$version"
if [ -n "$type" ] ; then
debver="$debver~$type"
fi
if [ -n "$distance" ] ; then
debver="$debver+$distance-$CODENAME-$node"
elif [ "$DEBFLAGS" = "-S" ] ; then
# for building a ppa (--source-only) for a release (distance == 0), we need
# to version the distroseries so that we can upload to launchpad
debver="$debver~${CODENAME}1"
fi
control=debian/control
changelog=debian/changelog
if [ "$BUILD" ]; then
if [ -d debian ] ; then
echo "Error! debian control directory already exists!"
exit 1
fi
cp -r $PWD/contrib/debian debian
sed -i.tmp "s/__VERSION__/$debver/" $changelog
sed -i.tmp "s/__DATE__/$(date --rfc-2822)/" $changelog
sed -i.tmp "s/__CODENAME__/$CODENAME/" $changelog
rm $changelog.tmp
# remove the node from the version string
SRCFILE="mercurial_$(echo $debver | sed "s,-$node,,").orig.tar.gz"
"$PWD/hg" archive $SRCFILE
mv $SRCFILE ..
debuild -us -uc -i -I $DEBFLAGS
if [ $? != 0 ]; then
echo 'debuild failed!'
exit 1
fi
fi
if [ "$CLEANUP" ] ; then
echo
OUTPUTDIR=${OUTPUTDIR:=packages/$DISTID-$CODENAME}
mkdir -p "$OUTPUTDIR"
find ../mercurial*.deb ../mercurial_*.build ../mercurial_*.changes \
../mercurial*.dsc ../mercurial*.gz \
-type f -newer $control -print0 2>/dev/null | \
xargs -Inarf -0 mv narf "$OUTPUTDIR"
echo "Built packages for $debver:"
find "$OUTPUTDIR" -type f -newer $control -name '*.deb'
fi