Please consider the example script and profile below. In the part of the profile that describes the invocation of the function "func" the line number in the cost line is 6. This is the line from where it was called(as described in the cfn block for that function) and not the line where the function is defined.

http://valgrind.org/docs/manual/cl-format.html section 3.1.2 paragraph 3 states:
"Thus, the first cost line specifies that in line 15 of source file "file.f" there is code belonging to function "main"."

As I understand that, the line number should point to code belonging to the function, just as the fl parameter is the file containing the function.

Script (line numbers added)

1 <?php
2 function func(){
3 1+1;
4 }
5
6 func();

Profile

version: 0.9.6
cmd: /Users/jacob/development/webdev/docroot/webgrind/test.php
part: 1

events: Time

fl=/Users/jacob/development/webdev/docroot/webgrind/test.php
fn=func
6 51

fl=/Users/jacob/development/webdev/docroot/webgrind/test.php
fn={main}

summary: 135

0 83
cfn=func
calls=1 0 0
6 51