Merge branch 'mh/attr'

* mh/attr:
Unroll the loop over passes
Change while loop into for loop
Determine the start of the states outside of the pass loop
Change parse_attr() to take a pointer to struct attr_state
Increment num_attr in parse_attr_line(), not parse_attr()
Document struct match_attr
Add a file comment

diff --cc attr.c
Simple merge