glibc/scripts/bench.pl
Siddhesh Poyarekar d569c6eeb4 Maintain runtime of each benchmark at ~10 seconds
The idea to run benchmarks for a constant number of iterations is
problematic.  While the benchmarks may run for 10 seconds on x86_64,
they could run for about 30 seconds on powerpc and worse, over 3
minutes on arm.  Besides that, adding a new benchmark is cumbersome
since one needs to find out the number of iterations needed for a
sufficient runtime.

A better idea would be to run each benchmark for a specific amount of
time.  This patch does just that.  The run time defaults to 10 seconds
and it is configurable at command line:

  make BENCH_DURATION=5 bench
2013-04-30 14:10:20 +05:30

92 lines
2.2 KiB
Perl
Executable File

#! /usr/bin/perl -w
# Copyright (C) 2013 Free Software Foundation, Inc.
# This file is part of the GNU C Library.
# The GNU C Library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
# The GNU C Library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public
# License along with the GNU C Library; if not, see
# <http://www.gnu.org/licenses/>.
use strict;
use warnings;
# Generate a benchmark source file for a given input.
if (@ARGV < 2) {
die "Usage: bench.pl <function> [parameter types] [return type]"
}
my $arg;
my $func = $ARGV[0];
my @args;
my $ret = "void";
my $getret = "";
my $retval = "";
if (@ARGV >= 2) {
@args = split(':', $ARGV[1]);
}
if (@ARGV == 3) {
$ret = $ARGV[2];
}
my $decl = "extern $ret $func (";
if (@args == 0 || $args[0] eq "void") {
print "$decl void);\n";
print "#define CALL_BENCH_FUNC(j) $func();\n";
print "#define NUM_SAMPLES (1)\n";
}
else {
my $num = 0;
my $bench_func = "#define CALL_BENCH_FUNC(j) $func (";
my $struct = "struct args {";
foreach $arg (@args) {
if ($num > 0) {
$bench_func = "$bench_func,";
$decl = "$decl,";
}
$struct = "$struct $arg arg$num;";
$bench_func = "$bench_func in[j].arg$num";
$decl = "$decl $arg";
$num = $num + 1;
}
print "$decl);\n";
print "$bench_func);\n";
print "$struct } in[] = {";
open INPUTS, "<$func-inputs" or die $!;
while (<INPUTS>) {
chomp;
print "{$_},\n";
}
print "};\n";
print "#define NUM_SAMPLES (sizeof (in) / sizeof (struct args))\n"
}
# In some cases not storing a return value seems to result in the function call
# being optimized out.
if ($ret ne "void") {
print "static volatile $ret ret = 0.0;\n";
$getret = "ret = ";
}
print "#define BENCH_FUNC(j) ({$getret CALL_BENCH_FUNC (j);})\n";
print "#define FUNCNAME \"$func\"\n";
print "#include \"bench-skeleton.c\"\n";