Merge branch 'sg/line-log-tree-diff-optim'

Optimize unnecessary full-tree diff away from "git log -L" machinery.

* sg/line-log-tree-diff-optim:
line-log: avoid unnecessary full tree diffs
line-log: extract pathspec parsing from line ranges into a helper function

diff --combined line-log.c
index 3aff1849e7d5c7dba5c14b2fa34f7af64064a42d,42c5e41f68dc206984709718cb3b3bdf8716cb5c..9010e00950b379501a6607d660497e94f8412d95
--- 1/line-log.c
--- 2/line-log.c
+++ b/line-log.c
@@@ -496,13 -496,12 +496,13 @@@ static struct commit *check_single_comm
        return (struct commit *) commit;
  }
  
 -static void fill_blob_sha1(struct commit *commit, struct diff_filespec *spec)
 +static void fill_blob_sha1(struct repository *r, struct commit *commit,
 +                         struct diff_filespec *spec)
  {
        unsigned short mode;
        struct object_id oid;
  
 -      if (get_tree_entry(&commit->object.oid, spec->path, &oid, &mode))
 +      if (get_tree_entry(r, &commit->object.oid, spec->path, &oid, &mode))
                die("There is no path %s in the commit", spec->path);
        fill_filespec(spec, &oid, 1, mode);
  
@@@ -586,7 -585,7 +586,7 @@@ parse_lines(struct repository *r, struc
                                        name_part);
  
                spec = alloc_filespec(full_name);
 -              fill_blob_sha1(commit, spec);
 +              fill_blob_sha1(r, commit, spec);
                fill_line_ends(r, spec, &lines, &ends);
                cb_data.spec = spec;
                cb_data.lines = lines;
@@@ -737,6 -736,38 +737,38 @@@ static struct line_log_data *lookup_lin
        return ret;
  }
  
+ static int same_paths_in_pathspec_and_range(struct pathspec *pathspec,
+                                           struct line_log_data *range)
+ {
+       int i;
+       struct line_log_data *r;
+ 
+       for (i = 0, r = range; i < pathspec->nr && r; i++, r = r->next)
+               if (strcmp(pathspec->items[i].match, r->path))
+                       return 0;
+       if (i < pathspec->nr || r)
+               /* different number of pathspec items and ranges */
+               return 0;
+ 
+       return 1;
+ }
+ 
+ static void parse_pathspec_from_ranges(struct pathspec *pathspec,
+                                      struct line_log_data *range)
+ {
+       struct line_log_data *r;
+       struct argv_array array = ARGV_ARRAY_INIT;
+       const char **paths;
+ 
+       for (r = range; r; r = r->next)
+               argv_array_push(&array, r->path);
+       paths = argv_array_detach(&array);
+ 
+       parse_pathspec(pathspec, 0, PATHSPEC_PREFER_FULL, "", paths);
+       /* strings are now owned by pathspec */
+       free(paths);
+ }
+ 
  void line_log_init(struct rev_info *rev, const char *prefix, struct string_list *args)
  {
        struct commit *commit = NULL;
@@@ -746,20 -777,7 +778,7 @@@
        range = parse_lines(rev->diffopt.repo, commit, prefix, args);
        add_line_range(rev, commit, range);
  
-       if (!rev->diffopt.detect_rename) {
-               struct line_log_data *r;
-               struct argv_array array = ARGV_ARRAY_INIT;
-               const char **paths;
- 
-               for (r = range; r; r = r->next)
-                       argv_array_push(&array, r->path);
-               paths = argv_array_detach(&array);
- 
-               parse_pathspec(&rev->diffopt.pathspec, 0,
-                              PATHSPEC_PREFER_FULL, "", paths);
-               /* strings are now owned by pathspec */
-               free(paths);
-       }
+       parse_pathspec_from_ranges(&rev->diffopt.pathspec, range);
  }
  
  static void move_diff_queue(struct diff_queue_struct *dst,
@@@ -817,15 -835,29 +836,29 @@@ static void queue_diffs(struct line_log
                        struct diff_queue_struct *queue,
                        struct commit *commit, struct commit *parent)
  {
+       struct object_id *tree_oid, *parent_tree_oid;
+ 
        assert(commit);
  
+       tree_oid = get_commit_tree_oid(commit);
+       parent_tree_oid = parent ? get_commit_tree_oid(parent) : NULL;
+ 
+       if (opt->detect_rename &&
+           !same_paths_in_pathspec_and_range(&opt->pathspec, range)) {
+               clear_pathspec(&opt->pathspec);
+               parse_pathspec_from_ranges(&opt->pathspec, range);
+       }
        DIFF_QUEUE_CLEAR(&diff_queued_diff);
-       diff_tree_oid(parent ? get_commit_tree_oid(parent) : NULL,
-                     get_commit_tree_oid(commit), "", opt);
-       if (opt->detect_rename) {
+       diff_tree_oid(parent_tree_oid, tree_oid, "", opt);
+       if (opt->detect_rename && diff_might_be_rename()) {
+               /* must look at the full tree diff to detect renames */
+               clear_pathspec(&opt->pathspec);
+               DIFF_QUEUE_CLEAR(&diff_queued_diff);
+ 
+               diff_tree_oid(parent_tree_oid, tree_oid, "", opt);
+ 
                filter_diffs_for_paths(range, 1);
-               if (diff_might_be_rename())
-                       diffcore_std(opt);
+               diffcore_std(opt);
                filter_diffs_for_paths(range, 0);
        }
        move_diff_queue(queue, &diff_queued_diff);