1 Commits

Author	SHA1	Message	Date
Dodji Seketeli	9be945584a	Re-write middle snakes management in core diff algorithms ... * include/abg-diff-utils.h (point::set): New overload.. (point::{add, operator<, operator>, operator<=, operator>=}): New methods. (point::operator!=): Constify. (point::operator==): Constify. Cleanup. (point::operator=): Keep emptiness. (class snake): New class definition (d_path_vec::{over_bounds, offset}): New methods. (d_path_vec::check_index_against_bound): Don't take a bound parameter anymore. Use the new over_bound method above. Fix up error reporting. (d_path_vec::d_path_vec): Fix d_path_vec size allocation. (d_path_vec::operator[]): Use the d_path_vec::at method to check all accesses against the bounds. This is slower, but at least we can expect to have something that is more robust. We can remove the bound checking later when we are sure the code has been tested enough. Also use the new offset() method. (d_path_vec::at): Take long long. (ends_of_furthest_d_paths_overlap): Constify input parameters. (end_of_fr_d_path_in_k, end_of_frr_d_path_in_k_plus_delta): Take an instance of the new snake in parameter, rather than a bare end point that wasn't carrying enough information about the snake. Record the snake which consists of up to four points: a begin point, an intermediate point, a diagonal start point and an end point. Return that snake upon successful completion. (compute_middle_snake): Take an instance of snake, rather than the two points that were supposed to represent a snake and with which we were loosing information before. Revisit/simplify the logic of this function; this literally goes forward or in reverse, gets the resulting snake returned by the end_of_fr_d_path_in_k and end_of_frr_d_path_in_k_plus_delta functions, detect if these snakes overlap and just return the current snake. Much simpler. The caller now gets a snake, which has much more information than the previous snake approximation made of just two points. Bonus point, this follows almost to the word, what the paper says. (maybe_record_match_point, find_snake_start_point): Remove these as there are not used by compute_middle_snake anymore. (print_snake, ses_len): Update these to take/handle a snake. (snake_end_points): New declaration. (compute_diff): When we are getting an empty first sequence, this means that we are inserting the second sequence *before* the beginning of the first sequence; keep this information by setting the insertion point index to -1, rather than zero. Update this to get/handle snakes, rather than free points vaguely representing snakes. Now that compute_middle_snake returns real snakes, handle the information we are getting. Basically for edit scripts of length equal to 1, as the snake carries all the necessary information about the non-diagonal edge (as well as the diagonal edges), we (can) now precisely update the current edit script (as well as the longest common sub-sequence). For edit scripts of length greater than 1, better at which points to divide the problem and consequently, at which points to conquer it back -- better following The Paper to the letter. (display_edit_script): Update this for the use of instances of snake. * src/abg-diff-utils.cc (ends_of_furthest_d_paths_overlap): Update for constification of inputs. (snake_end_points): Define new function. (compute_middle_snake): Adapt for the taking an instance of snake. * tests/test-diff2.cc (main): Update for using instances of snake. * tests/test-core-diff.cc: Add new tests. * tests/data/test-core-diff/report0.txt: Update for output adaptation. * tests/data/test-core-diff/report6.txt: Likewise. * tests/data/test-core-diff/report7.txt: Likewise. * tests/data/test-core-diff/report8.txt: New test data. * tests/data/test-core-diff/report9.txt: Likewise. * tests/data/test-core-diff/report10.txt: Likewise. * tests/data/test-core-diff/report11.txt: Likewise. * tests/data/test-core-diff/report12.txt: Likewise. * tests/data/test-core-diff/report3.txt: Likewise. Signed-off-by: Dodji Seketeli <dodji@redhat.com>	2013-11-19 11:25:47 +01:00