code: func (loc *Location) lastMatchedLineIndex(re *regexp.Regexp) int {
  	for i := len(loc.Line) - 1; i >= 0; i-- {
  		if fn := loc.Line[i].Function; fn != nil {
  			if re.MatchString(fn.Name) || re.MatchString(fn.Filename) {
  				return i
  			}
  		}
  	}
  	return -1
  }
docs: // lastMatchedLineIndex returns the index of the last line that matches a regex,
  // or -1 if no match is found.