mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-12-02 10:00:54 +00:00
157 lines
3.3 KiB
Perl
157 lines
3.3 KiB
Perl
# This Source Code Form is subject to the terms of the Mozilla Public
|
||
# License, v. 2.0. If a copy of the MPL was not distributed with this
|
||
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
||
package TraceMalloc;
|
||
|
||
use strict;
|
||
|
||
# Read in the type inference file and construct a network that we can
|
||
# use to match stack prefixes to types.
|
||
sub init_type_inference($) {
|
||
my ($file) = @_;
|
||
|
||
$::Fingerprints = { };
|
||
|
||
open(TYPES, "<$file") || die "unable to open $::opt_types, $!";
|
||
|
||
TYPE: while (<TYPES>) {
|
||
next TYPE unless /<(.*)>/;
|
||
my $type = $1;
|
||
|
||
my $link = \%::Fingerprints;
|
||
|
||
FRAME: while (<TYPES>) {
|
||
chomp;
|
||
last FRAME if /^$/;
|
||
|
||
my $next = $link->{$_};
|
||
if (! $next) {
|
||
$next = $link->{$_} = {};
|
||
}
|
||
$link = $next;
|
||
}
|
||
|
||
$link->{'#type#'} = $type;
|
||
|
||
last TYPE if eof;
|
||
}
|
||
}
|
||
|
||
# Infer the type, trying to find the most specific type possible.
|
||
sub infer_type($) {
|
||
my ($stack) = @_;
|
||
|
||
my $link = \%::Fingerprints;
|
||
my $last;
|
||
my $type = 'void*';
|
||
FRAME: foreach my $frame (@$stack) {
|
||
last FRAME unless $link;
|
||
|
||
$frame =~ s/\[.*\]$//; # ignore exact addresses, as they'll drift
|
||
|
||
$last = $link;
|
||
|
||
#
|
||
# Remember this type, but keep going. We use the longest match
|
||
# we find, but substacks of longer matches will also match.
|
||
#
|
||
if ($last->{'#type#'}) {
|
||
$type = $last->{'#type#'};
|
||
}
|
||
|
||
$link = $link->{$frame};
|
||
|
||
if (! $link) {
|
||
CHILD: foreach my $child (keys %$last) {
|
||
next CHILD unless $child =~ /^~/;
|
||
|
||
$child =~ s/^~//;
|
||
|
||
if ($frame =~ $child) {
|
||
$link = $last->{'~' . $child};
|
||
last CHILD;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
return $type;
|
||
}
|
||
|
||
|
||
#----------------------------------------------------------------------
|
||
#
|
||
# Read in the output a trace malloc's dump.
|
||
#
|
||
sub read {
|
||
my ($callback, $noslop) = @_;
|
||
|
||
OBJECT: while (<>) {
|
||
# e.g., 0x0832FBD0 <void*> (80)
|
||
next OBJECT unless /^0x(\S+) <(.*)> \((\d+)\)/;
|
||
my ($addr, $type, $size) = (hex $1, $2, $3);
|
||
|
||
my $object = { 'type' => $type, 'size' => $size };
|
||
|
||
# Record the object's slots
|
||
my @slots;
|
||
|
||
SLOT: while (<>) {
|
||
# e.g., 0x00000000
|
||
last SLOT unless /^\t0x(\S+)/;
|
||
my $value = hex $1;
|
||
|
||
# Ignore low bits, unless they've specified --noslop
|
||
$value &= ~0x7 unless $noslop;
|
||
|
||
$slots[$#slots + 1] = $value;
|
||
}
|
||
|
||
$object->{'slots'} = \@slots;
|
||
|
||
# Record the stack by which the object was allocated
|
||
my @stack;
|
||
|
||
while (/^(.*)\[(.*) \+0x(\S+)\]$/) {
|
||
# e.g., _dl_debug_message[/lib/ld-linux.so.2 +0x0000B858]
|
||
my ($func, $lib, $off) = ($1, $2, hex $3);
|
||
|
||
chomp;
|
||
$stack[$#stack + 1] = $_;
|
||
|
||
$_ = <>;
|
||
}
|
||
|
||
$object->{'stack'} = \@stack;
|
||
|
||
$object->{'type'} = infer_type(\@stack)
|
||
if $object->{'type'} eq 'void*';
|
||
|
||
&$callback($object) if $callback;
|
||
|
||
# Gotta check EOF explicitly...
|
||
last OBJECT if eof;
|
||
}
|
||
}
|
||
|
||
1;
|
||
__END__
|
||
|
||
=head1 NAME
|
||
|
||
TraceMalloc - Perl routines to deal with output from ``trace malloc''
|
||
and the Boehm GC
|
||
|
||
=head1 SYNOPSIS
|
||
|
||
use TraceMalloc;
|
||
|
||
TraceMalloc::init_type_inference("types.dat");
|
||
TraceMalloc::read(0);
|
||
|
||
=head1 DESCRIPTION
|
||
|
||
=head1 EXAMPLES
|
||
|
||
=cut
|