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