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Revision 531942d353758305e29879654b93f4ba3dcbcc63 authored by Elijah Newren on 28 September 2020, 17:37:16 UTC, committed by Elijah Newren on 13 October 2020, 22:37:51 UTC
Testcases 12b and 12c were both slightly weird; they were marked as having a weird resolution, but with the note that even straightforward simple rules can give weird results when the input is bizarre. However, during optimization work for merge-ort, I discovered a significant speedup that is possible if we add one more fairly straightforward rule: we don't bother doing directory rename detection if there are no new files added to the directory on the other side of the history to be affected by the directory rename. This seems like an obvious and straightforward rule, but there was one funny corner case where directory rename detection could affect only existing files: the funny corner case where two directories are renamed into each other on opposite sides of history. In other words, it only results in a different output for testcases 12b and 12c. Since we already thought testcases 12b and 12c were weird anyway, and because the optimization often has a significant effect on common cases (but is entirely prevented if we can't change how 12b and 12c function), let's add the additional rule and tweak how 12b and 12c work. Split both testcases into two (one where we add no new files, and one where the side that doesn't rename a given directory will add files to it), and mark them with the new expectation. Signed-off-by: Elijah Newren <newren@gmail.com>
1 parent 146d6f4
Tip revision: 531942d353758305e29879654b93f4ba3dcbcc63 authored by Elijah Newren on 28 September 2020, 17:37:16 UTC
t6423: more involved rules for renaming directories into each other
t6423: more involved rules for renaming directories into each other
Tip revision: 531942d
replace-object.h
#ifndef REPLACE_OBJECT_H
#define REPLACE_OBJECT_H
#include "oidmap.h"
#include "repository.h"
#include "object-store.h"
struct replace_object {
struct oidmap_entry original;
struct object_id replacement;
};
void prepare_replace_object(struct repository *r);
/*
* This internal function is only declared here for the benefit of
* lookup_replace_object(). Please do not call it directly.
*/
const struct object_id *do_lookup_replace_object(struct repository *r,
const struct object_id *oid);
/*
* If object sha1 should be replaced, return the replacement object's
* name (replaced recursively, if necessary). The return value is
* either sha1 or a pointer to a permanently-allocated value. When
* object replacement is suppressed, always return sha1.
*
* Note: some thread debuggers might point a data race on the
* replace_map_initialized reading in this function. However, we know there's no
* problem in the value being updated by one thread right after another one read
* it here (and it should be written to only once, anyway).
*/
static inline const struct object_id *lookup_replace_object(struct repository *r,
const struct object_id *oid)
{
if (!read_replace_refs ||
(r->objects->replace_map_initialized &&
r->objects->replace_map->map.tablesize == 0))
return oid;
return do_lookup_replace_object(r, oid);
}
#endif /* REPLACE_OBJECT_H */
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