Framework for performance benchmarking of functions

See benchtests/Makefile to know how to use it.

1 files changed, 93 insertions, 0 deletions

diff --git a/scripts/bench.pl b/scripts/bench.pl
new file mode 100755
index 0000000000..bb7f64897e
--- /dev/null
+++ b/scripts/bench.pl
@@ -0,0 +1,93 @@
+#! /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> <iterations> [parameter types] [return type]"
+}
+
+my $arg;
+my $func = $ARGV[0];
+my $iters = $ARGV[1];
+my @args;
+my $ret = "void";
+my $getret = "";
+my $retval = "";
+
+if (@ARGV >= 3) {
+  @args = split(':', $ARGV[2]);
+}
+
+if (@ARGV == 4) {
+  $ret = $ARGV[3];
+}
+
+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 ITER $iters\n";
+print "#define FUNCNAME \"$func\"\n";
+print "#include \"bench-skeleton.c\"\n";