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Differential D2629

xdiff: do not rely on hashtable in xdl_trim_ends
AbandonedPublic

Authored by quark on Mar 3 2018, 9:51 PM.

Details

Reviewers
None
Group Reviewers
hg-reviewers
Summary

Upcoming changes will narrow down the hashtable content to not include
trimmed lines. So let's just compare line contents in xdl_trim_ends.
It's still cheaper than calculating unique hash values for all lines.

Diff Detail

Repository
rHG Mercurial
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Unit
Unit Tests Skipped

Revision Contents
Changeset List

Diff 6528

mercurial/thirdparty/xdiff/xprepare.c

*/ */
static int xdl_trim_ends(xdfile_t *xdf1, xdfile_t *xdf2) { static int xdl_trim_ends(xdfile_t *xdf1, xdfile_t *xdf2) {
long i, lim; long i, lim;
xrecord_t **recs1, **recs2; xrecord_t **recs1, **recs2;
recs1 = xdf1->recs; recs1 = xdf1->recs;
recs2 = xdf2->recs; recs2 = xdf2->recs;
for (i = 0, lim = XDL_MIN(xdf1->nrec, xdf2->nrec); i < lim; for (i = 0, lim = XDL_MIN(xdf1->nrec, xdf2->nrec); i < lim;
i++, recs1++, recs2++) i++, recs1++, recs2++) {
if ((*recs1)->ha != (*recs2)->ha) /* rec->ha is not processed by xdl_prepare_hashtable, so
* they are not unique - do a content match here */
if ((*recs1)->size != (*recs2)->size)
break; break;
if (memcmp((*recs1)->ptr, (*recs2)->ptr, (*recs1)->size) != 0)
break;
}
xdf1->dstart = xdf2->dstart = i; xdf1->dstart = xdf2->dstart = i;
recs1 = xdf1->recs + xdf1->nrec - 1; recs1 = xdf1->recs + xdf1->nrec - 1;
recs2 = xdf2->recs + xdf2->nrec - 1; recs2 = xdf2->recs + xdf2->nrec - 1;
for (lim -= i, i = 0; i < lim; i++, recs1--, recs2--) for (lim -= i, i = 0; i < lim; i++, recs1--, recs2--) {
if ((*recs1)->ha != (*recs2)->ha) /* rec->ha is not processed by xdl_prepare_hashtable, so
* they are not unique - do a content match here */
if ((*recs1)->size != (*recs2)->size)
break; break;
if (memcmp((*recs1)->ptr, (*recs2)->ptr, (*recs1)->size) != 0)
break;
}
xdf1->dend = xdf1->nrec - i - 1; xdf1->dend = xdf1->nrec - i - 1;
xdf2->dend = xdf2->nrec - i - 1; xdf2->dend = xdf2->nrec - i - 1;
return 0; return 0;
} }