maint/RunBenchmark

#! /bin/sh
#
# Compile maint/pcre2bench.c, which no PCRE2 build system builds, against an
# already-built PCRE2 tree and run it.
#
# Usage: maint/RunBenchmark [-8|-16|-32] <build-dir> [label] [nojit] [short]
#
# <build-dir> is a directory in which the library has been built, by CMake or
# by autotools; both layouts are recognized. -8, -16 and -32 select the code
# unit width to benchmark, defaulting to 8; that library must have been built.
# The remaining arguments are passed to the driver, and are described at the
# start of pcre2bench.c. If no label is given, the build directory name is
# used.
#
# Output is TSV on stdout, so a comparison between two builds is
#
#   maint/RunBenchmark build-before before > before.tsv
#   maint/RunBenchmark build-after  after  > after.tsv
#
# CC and CFLAGS are honored; CFLAGS defaults to -O2.

set -eu

CC=${CC:-cc}
CFLAGS=${CFLAGS:--O2}

width=8

usage()
{
  echo "usage: $0 [-8|-16|-32] <build-dir> [label] [nojit] [short]" >&2
  exit 2
}

while [ $# -ge 1 ]; do
  case $1 in
    -8|-16|-32) width=${1#-}; shift;;
    -*) usage;;
    *) break;;
  esac
done

[ $# -ge 1 ] || usage

build=$1
shift
[ -d "$build" ] || { echo "$0: no such directory: $build" >&2; exit 1; }
build=$(cd "$build" && pwd)
label=$(basename "$build")

here=$(cd "$(dirname "$0")" && pwd)
driver=$here/pcre2bench.c
[ -f "$driver" ] || { echo "$0: cannot find $driver" >&2; exit 1; }

# pcre2.h is generated, so it lives in the build tree, not in src.

header=$(find "$build" -name pcre2.h -print 2>/dev/null | head -1)
[ -n "$header" ] || {
  echo "$0: no generated pcre2.h under $build; is it a build tree?" >&2
  exit 1
}

# Autotools puts the libraries in .libs, CMake in the top of the build tree.

lib=$(find "$build" \( -name "libpcre2-$width.a" -o -name "libpcre2-$width.so" \
  -o -name "libpcre2-$width.dylib" -o -name "pcre2-$width.lib" \) \
  -print 2>/dev/null | head -1)
[ -n "$lib" ] || {
  echo "$0: no $width-bit library under $build; has it been built?" >&2
  exit 1
}

incdir=$(dirname "$header")
libdir=$(dirname "$lib")
binary=$build/pcre2bench-$width

$CC $CFLAGS -DPCRE2_CODE_UNIT_WIDTH="$width" -o "$binary" "$driver" \
  -I"$incdir" -L"$libdir" "-lpcre2-$width" -Wl,-rpath,"$libdir"

# The driver takes the label as its first argument, so supply the build
# directory name unless the caller passed something that is not an option.

labelled=no
for arg in "$@"; do
  case $arg in
    nojit|short) ;;
    *) labelled=yes ;;
  esac
done
[ $labelled = yes ] || set -- "$label" "$@"

exec "$binary" "$@"

# End of RunBenchmark