arch: clean up isa_parser error handling
Review Request #3093 - Created Sept. 4, 2015 and submitted
Changeset 11080:57bba48b86ae --------------------------- arch: clean up isa_parser error handling Although some decent error messages were getting generated inside isa_parser.py, they weren't always getting printed because of the screwy way we were handling exceptions. (Basically an inner exception would get hidden by an outer exception, and the more informative inner error message would not get printed.) Also line numbers were messed up, since they were taken from the lexer, which is typically a token (or more) ahead of the grammar rule that's being matched. Using the 'lineno' attribute that PLY associates with the grammar production is more accurate. The new LineTracker class extends lineno to track filenames as well as line numbers.