mirror of
https://github.com/git/git
synced 2024-08-25 10:45:59 +00:00
![Elijah Newren](/assets/img/avatar_default.png)
Add some timing instrumentation for both merge-ort and diffcore-rename; I used these to measure and optimize performance in both, and several future patch series will build on these to reduce the timings of some select testcases. === Setup === The primary testcase I used involved rebasing a random topic in the linux kernel (consisting of 35 patches) against an older version. I added two variants, one where I rename a toplevel directory, and another where I only rebase one patch instead of the whole topic. The setup is as follows: $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git $ git branch hwmon-updates fd8bdb23b91876ac1e624337bb88dc1dcc21d67e $ git branch hwmon-just-one fd8bdb23b91876ac1e624337bb88dc1dcc21d67e~34 $ git branch base 4703d9119972bf586d2cca76ec6438f819ffa30e $ git switch -c 5.4-renames v5.4 $ git mv drivers pilots # Introduce over 26,000 renames $ git commit -m "Rename drivers/ to pilots/" $ git config merge.renameLimit 30000 $ git config merge.directoryRenames true === Testcases === Now with REBASE standing for either "git rebase [--merge]" (using merge-recursive) or "test-tool fast-rebase" (using merge-ort), the testcases are: Testcase #1: no-renames $ git checkout v5.4^0 $ REBASE --onto HEAD base hwmon-updates Note: technically the name is misleading; there are some renames, but very few. Rename detection only takes about half the overall time. Testcase #2: mega-renames $ git checkout 5.4-renames^0 $ REBASE --onto HEAD base hwmon-updates Testcase #3: just-one-mega $ git checkout 5.4-renames^0 $ REBASE --onto HEAD base hwmon-just-one === Timing results === Overall timings, using hyperfine (1 warmup run, 3 runs for mega-renames, 10 runs for the other two cases): merge-recursive merge-ort no-renames: 18.912 s ± 0.174 s 14.263 s ± 0.053 s mega-renames: 5964.031 s ± 10.459 s 5504.231 s ± 5.150 s just-one-mega: 149.583 s ± 0.751 s 158.534 s ± 0.498 s A single re-run of each with some breakdowns: --- no-renames --- merge-recursive merge-ort overall runtime: 19.302 s 14.257 s inexact rename detection: 7.603 s 7.906 s everything else: 11.699 s 6.351 s --- mega-renames --- merge-recursive merge-ort overall runtime: 5950.195 s 5499.672 s inexact rename detection: 5746.309 s 5487.120 s everything else: 203.886 s 17.552 s --- just-one-mega --- merge-recursive merge-ort overall runtime: 151.001 s 158.582 s inexact rename detection: 143.448 s 157.835 s everything else: 7.553 s 0.747 s === Timing observations === 0) Maximum speedup The "everything else" row represents the maximum speedup we could achieve if we were to somehow infinitely parallelize inexact rename detection, but leave everything else alone. The fact that this is so much smaller than the real runtime (even in the case with virtually no renames) makes it clear just how overwhelmingly large the time spent on rename detection can be. 1) no-renames 1a) merge-ort is faster than merge-recursive, which is nice. However, this still should not be considered good enough. Although the "merge" backend to rebase (merge-recursive) is sometimes faster than the "apply" backend, this is one of those cases where it is not. In fact, even merge-ort is slower. The "apply" backend can complete this testcase in 6.940 s ± 0.485 s which is about 2x faster than merge-ort and 3x faster than merge-recursive. One goal of the merge-ort performance work will be to make it faster than git-am on this (and similar) testcases. 2) mega-renames 2a) Obviously rename detection is a huge cost; it's where most the time is spent. We need to cut that down. If we could somehow infinitely parallelize it and drive its time to 0, the merge-recursive time would drop to about 204s, and the merge-ort time would drop to about 17s. I think this particular stat shows I've subtly baked a couple performance improvements into merge-ort and into fast-rebase already. 3) just-one-mega 3a) not much to say here, it just gives some flavor for how rebasing only one patch compares to rebasing 35. === Goals === This patch is obviously just the beginning. Here are some of my goals that this measurement will help us achieve: * Drive the cost of rename detection down considerably for merges * After the above has been achieved, see if there are other slowness factors (which would have previously been overshadowed by rename detection costs) which we can then focus on and also optimize. * Ensure our rebase testcase that requires little rename detection is noticeably faster with merge-ort than with apply-based rebase. Signed-off-by: Elijah Newren <newren@gmail.com> Acked-by: Taylor Blau <ttaylorr@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
693 lines
19 KiB
C
693 lines
19 KiB
C
/*
|
|
*
|
|
* Copyright (C) 2005 Junio C Hamano
|
|
*/
|
|
#include "cache.h"
|
|
#include "diff.h"
|
|
#include "diffcore.h"
|
|
#include "object-store.h"
|
|
#include "hashmap.h"
|
|
#include "progress.h"
|
|
#include "promisor-remote.h"
|
|
#include "strmap.h"
|
|
|
|
/* Table of rename/copy destinations */
|
|
|
|
static struct diff_rename_dst {
|
|
struct diff_filepair *p;
|
|
struct diff_filespec *filespec_to_free;
|
|
int is_rename; /* false -> just a create; true -> rename or copy */
|
|
} *rename_dst;
|
|
static int rename_dst_nr, rename_dst_alloc;
|
|
/* Mapping from break source pathname to break destination index */
|
|
static struct strintmap *break_idx = NULL;
|
|
|
|
static struct diff_rename_dst *locate_rename_dst(struct diff_filepair *p)
|
|
{
|
|
/* Lookup by p->ONE->path */
|
|
int idx = break_idx ? strintmap_get(break_idx, p->one->path) : -1;
|
|
return (idx == -1) ? NULL : &rename_dst[idx];
|
|
}
|
|
|
|
/*
|
|
* Returns 0 on success, -1 if we found a duplicate.
|
|
*/
|
|
static int add_rename_dst(struct diff_filepair *p)
|
|
{
|
|
ALLOC_GROW(rename_dst, rename_dst_nr + 1, rename_dst_alloc);
|
|
rename_dst[rename_dst_nr].p = p;
|
|
rename_dst[rename_dst_nr].filespec_to_free = NULL;
|
|
rename_dst[rename_dst_nr].is_rename = 0;
|
|
rename_dst_nr++;
|
|
return 0;
|
|
}
|
|
|
|
/* Table of rename/copy src files */
|
|
static struct diff_rename_src {
|
|
struct diff_filepair *p;
|
|
unsigned short score; /* to remember the break score */
|
|
} *rename_src;
|
|
static int rename_src_nr, rename_src_alloc;
|
|
|
|
static void register_rename_src(struct diff_filepair *p)
|
|
{
|
|
if (p->broken_pair) {
|
|
if (!break_idx) {
|
|
break_idx = xmalloc(sizeof(*break_idx));
|
|
strintmap_init(break_idx, -1);
|
|
}
|
|
strintmap_set(break_idx, p->one->path, rename_dst_nr);
|
|
}
|
|
|
|
ALLOC_GROW(rename_src, rename_src_nr + 1, rename_src_alloc);
|
|
rename_src[rename_src_nr].p = p;
|
|
rename_src[rename_src_nr].score = p->score;
|
|
rename_src_nr++;
|
|
}
|
|
|
|
static int basename_same(struct diff_filespec *src, struct diff_filespec *dst)
|
|
{
|
|
int src_len = strlen(src->path), dst_len = strlen(dst->path);
|
|
while (src_len && dst_len) {
|
|
char c1 = src->path[--src_len];
|
|
char c2 = dst->path[--dst_len];
|
|
if (c1 != c2)
|
|
return 0;
|
|
if (c1 == '/')
|
|
return 1;
|
|
}
|
|
return (!src_len || src->path[src_len - 1] == '/') &&
|
|
(!dst_len || dst->path[dst_len - 1] == '/');
|
|
}
|
|
|
|
struct diff_score {
|
|
int src; /* index in rename_src */
|
|
int dst; /* index in rename_dst */
|
|
unsigned short score;
|
|
short name_score;
|
|
};
|
|
|
|
struct prefetch_options {
|
|
struct repository *repo;
|
|
int skip_unmodified;
|
|
};
|
|
static void prefetch(void *prefetch_options)
|
|
{
|
|
struct prefetch_options *options = prefetch_options;
|
|
int i;
|
|
struct oid_array to_fetch = OID_ARRAY_INIT;
|
|
|
|
for (i = 0; i < rename_dst_nr; i++) {
|
|
if (rename_dst[i].p->renamed_pair)
|
|
/*
|
|
* The loop in diffcore_rename() will not need these
|
|
* blobs, so skip prefetching.
|
|
*/
|
|
continue; /* already found exact match */
|
|
diff_add_if_missing(options->repo, &to_fetch,
|
|
rename_dst[i].p->two);
|
|
}
|
|
for (i = 0; i < rename_src_nr; i++) {
|
|
if (options->skip_unmodified &&
|
|
diff_unmodified_pair(rename_src[i].p))
|
|
/*
|
|
* The loop in diffcore_rename() will not need these
|
|
* blobs, so skip prefetching.
|
|
*/
|
|
continue;
|
|
diff_add_if_missing(options->repo, &to_fetch,
|
|
rename_src[i].p->one);
|
|
}
|
|
promisor_remote_get_direct(options->repo, to_fetch.oid, to_fetch.nr);
|
|
oid_array_clear(&to_fetch);
|
|
}
|
|
|
|
static int estimate_similarity(struct repository *r,
|
|
struct diff_filespec *src,
|
|
struct diff_filespec *dst,
|
|
int minimum_score,
|
|
int skip_unmodified)
|
|
{
|
|
/* src points at a file that existed in the original tree (or
|
|
* optionally a file in the destination tree) and dst points
|
|
* at a newly created file. They may be quite similar, in which
|
|
* case we want to say src is renamed to dst or src is copied into
|
|
* dst, and then some edit has been applied to dst.
|
|
*
|
|
* Compare them and return how similar they are, representing
|
|
* the score as an integer between 0 and MAX_SCORE.
|
|
*
|
|
* When there is an exact match, it is considered a better
|
|
* match than anything else; the destination does not even
|
|
* call into this function in that case.
|
|
*/
|
|
unsigned long max_size, delta_size, base_size, src_copied, literal_added;
|
|
int score;
|
|
struct diff_populate_filespec_options dpf_options = {
|
|
.check_size_only = 1
|
|
};
|
|
struct prefetch_options prefetch_options = {r, skip_unmodified};
|
|
|
|
if (r == the_repository && has_promisor_remote()) {
|
|
dpf_options.missing_object_cb = prefetch;
|
|
dpf_options.missing_object_data = &prefetch_options;
|
|
}
|
|
|
|
/* We deal only with regular files. Symlink renames are handled
|
|
* only when they are exact matches --- in other words, no edits
|
|
* after renaming.
|
|
*/
|
|
if (!S_ISREG(src->mode) || !S_ISREG(dst->mode))
|
|
return 0;
|
|
|
|
/*
|
|
* Need to check that source and destination sizes are
|
|
* filled in before comparing them.
|
|
*
|
|
* If we already have "cnt_data" filled in, we know it's
|
|
* all good (avoid checking the size for zero, as that
|
|
* is a possible size - we really should have a flag to
|
|
* say whether the size is valid or not!)
|
|
*/
|
|
if (!src->cnt_data &&
|
|
diff_populate_filespec(r, src, &dpf_options))
|
|
return 0;
|
|
if (!dst->cnt_data &&
|
|
diff_populate_filespec(r, dst, &dpf_options))
|
|
return 0;
|
|
|
|
max_size = ((src->size > dst->size) ? src->size : dst->size);
|
|
base_size = ((src->size < dst->size) ? src->size : dst->size);
|
|
delta_size = max_size - base_size;
|
|
|
|
/* We would not consider edits that change the file size so
|
|
* drastically. delta_size must be smaller than
|
|
* (MAX_SCORE-minimum_score)/MAX_SCORE * min(src->size, dst->size).
|
|
*
|
|
* Note that base_size == 0 case is handled here already
|
|
* and the final score computation below would not have a
|
|
* divide-by-zero issue.
|
|
*/
|
|
if (max_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
|
|
return 0;
|
|
|
|
dpf_options.check_size_only = 0;
|
|
|
|
if (!src->cnt_data && diff_populate_filespec(r, src, &dpf_options))
|
|
return 0;
|
|
if (!dst->cnt_data && diff_populate_filespec(r, dst, &dpf_options))
|
|
return 0;
|
|
|
|
if (diffcore_count_changes(r, src, dst,
|
|
&src->cnt_data, &dst->cnt_data,
|
|
&src_copied, &literal_added))
|
|
return 0;
|
|
|
|
/* How similar are they?
|
|
* what percentage of material in dst are from source?
|
|
*/
|
|
if (!dst->size)
|
|
score = 0; /* should not happen */
|
|
else
|
|
score = (int)(src_copied * MAX_SCORE / max_size);
|
|
return score;
|
|
}
|
|
|
|
static void record_rename_pair(int dst_index, int src_index, int score)
|
|
{
|
|
struct diff_filepair *src = rename_src[src_index].p;
|
|
struct diff_filepair *dst = rename_dst[dst_index].p;
|
|
|
|
if (dst->renamed_pair)
|
|
die("internal error: dst already matched.");
|
|
|
|
src->one->rename_used++;
|
|
src->one->count++;
|
|
|
|
rename_dst[dst_index].filespec_to_free = dst->one;
|
|
rename_dst[dst_index].is_rename = 1;
|
|
|
|
dst->one = src->one;
|
|
dst->renamed_pair = 1;
|
|
if (!strcmp(dst->one->path, dst->two->path))
|
|
dst->score = rename_src[src_index].score;
|
|
else
|
|
dst->score = score;
|
|
}
|
|
|
|
/*
|
|
* We sort the rename similarity matrix with the score, in descending
|
|
* order (the most similar first).
|
|
*/
|
|
static int score_compare(const void *a_, const void *b_)
|
|
{
|
|
const struct diff_score *a = a_, *b = b_;
|
|
|
|
/* sink the unused ones to the bottom */
|
|
if (a->dst < 0)
|
|
return (0 <= b->dst);
|
|
else if (b->dst < 0)
|
|
return -1;
|
|
|
|
if (a->score == b->score)
|
|
return b->name_score - a->name_score;
|
|
|
|
return b->score - a->score;
|
|
}
|
|
|
|
struct file_similarity {
|
|
struct hashmap_entry entry;
|
|
int index;
|
|
struct diff_filespec *filespec;
|
|
};
|
|
|
|
static unsigned int hash_filespec(struct repository *r,
|
|
struct diff_filespec *filespec)
|
|
{
|
|
if (!filespec->oid_valid) {
|
|
if (diff_populate_filespec(r, filespec, NULL))
|
|
return 0;
|
|
hash_object_file(r->hash_algo, filespec->data, filespec->size,
|
|
"blob", &filespec->oid);
|
|
}
|
|
return oidhash(&filespec->oid);
|
|
}
|
|
|
|
static int find_identical_files(struct hashmap *srcs,
|
|
int dst_index,
|
|
struct diff_options *options)
|
|
{
|
|
int renames = 0;
|
|
struct diff_filespec *target = rename_dst[dst_index].p->two;
|
|
struct file_similarity *p, *best = NULL;
|
|
int i = 100, best_score = -1;
|
|
unsigned int hash = hash_filespec(options->repo, target);
|
|
|
|
/*
|
|
* Find the best source match for specified destination.
|
|
*/
|
|
p = hashmap_get_entry_from_hash(srcs, hash, NULL,
|
|
struct file_similarity, entry);
|
|
hashmap_for_each_entry_from(srcs, p, entry) {
|
|
int score;
|
|
struct diff_filespec *source = p->filespec;
|
|
|
|
/* False hash collision? */
|
|
if (!oideq(&source->oid, &target->oid))
|
|
continue;
|
|
/* Non-regular files? If so, the modes must match! */
|
|
if (!S_ISREG(source->mode) || !S_ISREG(target->mode)) {
|
|
if (source->mode != target->mode)
|
|
continue;
|
|
}
|
|
/* Give higher scores to sources that haven't been used already */
|
|
score = !source->rename_used;
|
|
if (source->rename_used && options->detect_rename != DIFF_DETECT_COPY)
|
|
continue;
|
|
score += basename_same(source, target);
|
|
if (score > best_score) {
|
|
best = p;
|
|
best_score = score;
|
|
if (score == 2)
|
|
break;
|
|
}
|
|
|
|
/* Too many identical alternatives? Pick one */
|
|
if (!--i)
|
|
break;
|
|
}
|
|
if (best) {
|
|
record_rename_pair(dst_index, best->index, MAX_SCORE);
|
|
renames++;
|
|
}
|
|
return renames;
|
|
}
|
|
|
|
static void insert_file_table(struct repository *r,
|
|
struct hashmap *table, int index,
|
|
struct diff_filespec *filespec)
|
|
{
|
|
struct file_similarity *entry = xmalloc(sizeof(*entry));
|
|
|
|
entry->index = index;
|
|
entry->filespec = filespec;
|
|
|
|
hashmap_entry_init(&entry->entry, hash_filespec(r, filespec));
|
|
hashmap_add(table, &entry->entry);
|
|
}
|
|
|
|
/*
|
|
* Find exact renames first.
|
|
*
|
|
* The first round matches up the up-to-date entries,
|
|
* and then during the second round we try to match
|
|
* cache-dirty entries as well.
|
|
*/
|
|
static int find_exact_renames(struct diff_options *options)
|
|
{
|
|
int i, renames = 0;
|
|
struct hashmap file_table;
|
|
|
|
/* Add all sources to the hash table in reverse order, because
|
|
* later on they will be retrieved in LIFO order.
|
|
*/
|
|
hashmap_init(&file_table, NULL, NULL, rename_src_nr);
|
|
for (i = rename_src_nr-1; i >= 0; i--)
|
|
insert_file_table(options->repo,
|
|
&file_table, i,
|
|
rename_src[i].p->one);
|
|
|
|
/* Walk the destinations and find best source match */
|
|
for (i = 0; i < rename_dst_nr; i++)
|
|
renames += find_identical_files(&file_table, i, options);
|
|
|
|
/* Free the hash data structure and entries */
|
|
hashmap_clear_and_free(&file_table, struct file_similarity, entry);
|
|
|
|
return renames;
|
|
}
|
|
|
|
#define NUM_CANDIDATE_PER_DST 4
|
|
static void record_if_better(struct diff_score m[], struct diff_score *o)
|
|
{
|
|
int i, worst;
|
|
|
|
/* find the worst one */
|
|
worst = 0;
|
|
for (i = 1; i < NUM_CANDIDATE_PER_DST; i++)
|
|
if (score_compare(&m[i], &m[worst]) > 0)
|
|
worst = i;
|
|
|
|
/* is it better than the worst one? */
|
|
if (score_compare(&m[worst], o) > 0)
|
|
m[worst] = *o;
|
|
}
|
|
|
|
/*
|
|
* Returns:
|
|
* 0 if we are under the limit;
|
|
* 1 if we need to disable inexact rename detection;
|
|
* 2 if we would be under the limit if we were given -C instead of -C -C.
|
|
*/
|
|
static int too_many_rename_candidates(int num_destinations, int num_sources,
|
|
struct diff_options *options)
|
|
{
|
|
int rename_limit = options->rename_limit;
|
|
int i, limited_sources;
|
|
|
|
options->needed_rename_limit = 0;
|
|
|
|
/*
|
|
* This basically does a test for the rename matrix not
|
|
* growing larger than a "rename_limit" square matrix, ie:
|
|
*
|
|
* num_destinations * num_sources > rename_limit * rename_limit
|
|
*
|
|
* We use st_mult() to check overflow conditions; in the
|
|
* exceptional circumstance that size_t isn't large enough to hold
|
|
* the multiplication, the system won't be able to allocate enough
|
|
* memory for the matrix anyway.
|
|
*/
|
|
if (rename_limit <= 0)
|
|
rename_limit = 32767;
|
|
if (st_mult(num_destinations, num_sources)
|
|
<= st_mult(rename_limit, rename_limit))
|
|
return 0;
|
|
|
|
options->needed_rename_limit =
|
|
num_sources > num_destinations ? num_sources : num_destinations;
|
|
|
|
/* Are we running under -C -C? */
|
|
if (!options->flags.find_copies_harder)
|
|
return 1;
|
|
|
|
/* Would we bust the limit if we were running under -C? */
|
|
for (limited_sources = i = 0; i < num_sources; i++) {
|
|
if (diff_unmodified_pair(rename_src[i].p))
|
|
continue;
|
|
limited_sources++;
|
|
}
|
|
if (st_mult(num_destinations, limited_sources)
|
|
<= st_mult(rename_limit, rename_limit))
|
|
return 2;
|
|
return 1;
|
|
}
|
|
|
|
static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies)
|
|
{
|
|
int count = 0, i;
|
|
|
|
for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
|
|
struct diff_rename_dst *dst;
|
|
|
|
if ((mx[i].dst < 0) ||
|
|
(mx[i].score < minimum_score))
|
|
break; /* there is no more usable pair. */
|
|
dst = &rename_dst[mx[i].dst];
|
|
if (dst->is_rename)
|
|
continue; /* already done, either exact or fuzzy. */
|
|
if (!copies && rename_src[mx[i].src].p->one->rename_used)
|
|
continue;
|
|
record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
|
|
count++;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
void diffcore_rename(struct diff_options *options)
|
|
{
|
|
int detect_rename = options->detect_rename;
|
|
int minimum_score = options->rename_score;
|
|
struct diff_queue_struct *q = &diff_queued_diff;
|
|
struct diff_queue_struct outq;
|
|
struct diff_score *mx;
|
|
int i, j, rename_count, skip_unmodified = 0;
|
|
int num_destinations, dst_cnt;
|
|
struct progress *progress = NULL;
|
|
|
|
trace2_region_enter("diff", "setup", options->repo);
|
|
if (!minimum_score)
|
|
minimum_score = DEFAULT_RENAME_SCORE;
|
|
|
|
for (i = 0; i < q->nr; i++) {
|
|
struct diff_filepair *p = q->queue[i];
|
|
if (!DIFF_FILE_VALID(p->one)) {
|
|
if (!DIFF_FILE_VALID(p->two))
|
|
continue; /* unmerged */
|
|
else if (options->single_follow &&
|
|
strcmp(options->single_follow, p->two->path))
|
|
continue; /* not interested */
|
|
else if (!options->flags.rename_empty &&
|
|
is_empty_blob_oid(&p->two->oid))
|
|
continue;
|
|
else if (add_rename_dst(p) < 0) {
|
|
warning("skipping rename detection, detected"
|
|
" duplicate destination '%s'",
|
|
p->two->path);
|
|
goto cleanup;
|
|
}
|
|
}
|
|
else if (!options->flags.rename_empty &&
|
|
is_empty_blob_oid(&p->one->oid))
|
|
continue;
|
|
else if (!DIFF_PAIR_UNMERGED(p) && !DIFF_FILE_VALID(p->two)) {
|
|
/*
|
|
* If the source is a broken "delete", and
|
|
* they did not really want to get broken,
|
|
* that means the source actually stays.
|
|
* So we increment the "rename_used" score
|
|
* by one, to indicate ourselves as a user
|
|
*/
|
|
if (p->broken_pair && !p->score)
|
|
p->one->rename_used++;
|
|
register_rename_src(p);
|
|
}
|
|
else if (detect_rename == DIFF_DETECT_COPY) {
|
|
/*
|
|
* Increment the "rename_used" score by
|
|
* one, to indicate ourselves as a user.
|
|
*/
|
|
p->one->rename_used++;
|
|
register_rename_src(p);
|
|
}
|
|
}
|
|
trace2_region_leave("diff", "setup", options->repo);
|
|
if (rename_dst_nr == 0 || rename_src_nr == 0)
|
|
goto cleanup; /* nothing to do */
|
|
|
|
trace2_region_enter("diff", "exact renames", options->repo);
|
|
/*
|
|
* We really want to cull the candidates list early
|
|
* with cheap tests in order to avoid doing deltas.
|
|
*/
|
|
rename_count = find_exact_renames(options);
|
|
trace2_region_leave("diff", "exact renames", options->repo);
|
|
|
|
/* Did we only want exact renames? */
|
|
if (minimum_score == MAX_SCORE)
|
|
goto cleanup;
|
|
|
|
/*
|
|
* Calculate how many renames are left (but all the source
|
|
* files still remain as options for rename/copies!)
|
|
*/
|
|
num_destinations = (rename_dst_nr - rename_count);
|
|
|
|
/* All done? */
|
|
if (!num_destinations)
|
|
goto cleanup;
|
|
|
|
switch (too_many_rename_candidates(num_destinations, rename_src_nr,
|
|
options)) {
|
|
case 1:
|
|
goto cleanup;
|
|
case 2:
|
|
options->degraded_cc_to_c = 1;
|
|
skip_unmodified = 1;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
trace2_region_enter("diff", "inexact renames", options->repo);
|
|
if (options->show_rename_progress) {
|
|
progress = start_delayed_progress(
|
|
_("Performing inexact rename detection"),
|
|
(uint64_t)num_destinations * (uint64_t)rename_src_nr);
|
|
}
|
|
|
|
mx = xcalloc(st_mult(NUM_CANDIDATE_PER_DST, num_destinations),
|
|
sizeof(*mx));
|
|
for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
|
|
struct diff_filespec *two = rename_dst[i].p->two;
|
|
struct diff_score *m;
|
|
|
|
if (rename_dst[i].is_rename)
|
|
continue; /* dealt with exact match already. */
|
|
|
|
m = &mx[dst_cnt * NUM_CANDIDATE_PER_DST];
|
|
for (j = 0; j < NUM_CANDIDATE_PER_DST; j++)
|
|
m[j].dst = -1;
|
|
|
|
for (j = 0; j < rename_src_nr; j++) {
|
|
struct diff_filespec *one = rename_src[j].p->one;
|
|
struct diff_score this_src;
|
|
|
|
if (skip_unmodified &&
|
|
diff_unmodified_pair(rename_src[j].p))
|
|
continue;
|
|
|
|
this_src.score = estimate_similarity(options->repo,
|
|
one, two,
|
|
minimum_score,
|
|
skip_unmodified);
|
|
this_src.name_score = basename_same(one, two);
|
|
this_src.dst = i;
|
|
this_src.src = j;
|
|
record_if_better(m, &this_src);
|
|
/*
|
|
* Once we run estimate_similarity,
|
|
* We do not need the text anymore.
|
|
*/
|
|
diff_free_filespec_blob(one);
|
|
diff_free_filespec_blob(two);
|
|
}
|
|
dst_cnt++;
|
|
display_progress(progress,
|
|
(uint64_t)dst_cnt * (uint64_t)rename_src_nr);
|
|
}
|
|
stop_progress(&progress);
|
|
|
|
/* cost matrix sorted by most to least similar pair */
|
|
STABLE_QSORT(mx, dst_cnt * NUM_CANDIDATE_PER_DST, score_compare);
|
|
|
|
rename_count += find_renames(mx, dst_cnt, minimum_score, 0);
|
|
if (detect_rename == DIFF_DETECT_COPY)
|
|
rename_count += find_renames(mx, dst_cnt, minimum_score, 1);
|
|
free(mx);
|
|
trace2_region_leave("diff", "inexact renames", options->repo);
|
|
|
|
cleanup:
|
|
/* At this point, we have found some renames and copies and they
|
|
* are recorded in rename_dst. The original list is still in *q.
|
|
*/
|
|
trace2_region_enter("diff", "write back to queue", options->repo);
|
|
DIFF_QUEUE_CLEAR(&outq);
|
|
for (i = 0; i < q->nr; i++) {
|
|
struct diff_filepair *p = q->queue[i];
|
|
struct diff_filepair *pair_to_free = NULL;
|
|
|
|
if (DIFF_PAIR_UNMERGED(p)) {
|
|
diff_q(&outq, p);
|
|
}
|
|
else if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
|
|
/* Creation */
|
|
diff_q(&outq, p);
|
|
}
|
|
else if (DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two)) {
|
|
/*
|
|
* Deletion
|
|
*
|
|
* We would output this delete record if:
|
|
*
|
|
* (1) this is a broken delete and the counterpart
|
|
* broken create remains in the output; or
|
|
* (2) this is not a broken delete, and rename_dst
|
|
* does not have a rename/copy to move p->one->path
|
|
* out of existence.
|
|
*
|
|
* Otherwise, the counterpart broken create
|
|
* has been turned into a rename-edit; or
|
|
* delete did not have a matching create to
|
|
* begin with.
|
|
*/
|
|
if (DIFF_PAIR_BROKEN(p)) {
|
|
/* broken delete */
|
|
struct diff_rename_dst *dst = locate_rename_dst(p);
|
|
if (!dst)
|
|
BUG("tracking failed somehow; failed to find associated dst for broken pair");
|
|
if (dst->is_rename)
|
|
/* counterpart is now rename/copy */
|
|
pair_to_free = p;
|
|
}
|
|
else {
|
|
if (p->one->rename_used)
|
|
/* this path remains */
|
|
pair_to_free = p;
|
|
}
|
|
|
|
if (!pair_to_free)
|
|
diff_q(&outq, p);
|
|
}
|
|
else if (!diff_unmodified_pair(p))
|
|
/* all the usual ones need to be kept */
|
|
diff_q(&outq, p);
|
|
else
|
|
/* no need to keep unmodified pairs; FIXME: remove earlier? */
|
|
pair_to_free = p;
|
|
|
|
if (pair_to_free)
|
|
diff_free_filepair(pair_to_free);
|
|
}
|
|
diff_debug_queue("done copying original", &outq);
|
|
|
|
free(q->queue);
|
|
*q = outq;
|
|
diff_debug_queue("done collapsing", q);
|
|
|
|
for (i = 0; i < rename_dst_nr; i++)
|
|
if (rename_dst[i].filespec_to_free)
|
|
free_filespec(rename_dst[i].filespec_to_free);
|
|
|
|
FREE_AND_NULL(rename_dst);
|
|
rename_dst_nr = rename_dst_alloc = 0;
|
|
FREE_AND_NULL(rename_src);
|
|
rename_src_nr = rename_src_alloc = 0;
|
|
if (break_idx) {
|
|
strintmap_clear(break_idx);
|
|
FREE_AND_NULL(break_idx);
|
|
}
|
|
trace2_region_leave("diff", "write back to queue", options->repo);
|
|
return;
|
|
}
|