At present it is difficult (impossible?) to tell explicitly which function has been called by the "cfn=" lines, as there is no reference file "cfl=" given in the cachegrind files.

Example, given file1.php:

<?php
require "file2.php";
function func1() {
echo "This is func 1\n";
func2();
}
func1();
?>

and file2.php as:

<?php
function func2() {
echo "This is func 2\n";
}
?>

The profiler output from running "file1.php" is:

version: 0.9.6
cmd: /srv/www/htdocs/php/xdebug/file1.php
part: 1

events: Time

fl=/srv/www/htdocs/php/xdebug/file2.php
fn=require::/srv/www/htdocs/php/xdebug/file2.php
1 2

fl=/srv/www/htdocs/php/xdebug/file2.php
fn=func2
9 0

fl=/srv/www/htdocs/php/xdebug/file1.php
fn=func1
12 44
cfn=func2
calls=1 0 0
9 0

fl=/srv/www/htdocs/php/xdebug/file1.php
fn={main}

summary: 193

0 145
cfn=require::/srv/www/htdocs/php/xdebug/file2.php
calls=1 0 0
5 2
cfn=func1
calls=1 0 0
12 45

According to the valgrind docs:
http://valgrind.org/docs/manual/cl-format.html

if a "cfl=" is not specified, it defaults to the current file "fl=", which would give the indication that "cfn=func2" is thus defined in file1.php (which is incorrect).

Adding the line:
"cfl=/srv/www/htdocs/php/xdebug/file2.php"
before the "cfn=" would fix this ambiguous entry.