From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 12 Aug 2016 16:47:39 +0000 (-0700)
Subject: Merge branch 'kw/patch-ids-optim'
X-Git-Tag: v2.10.0-rc0~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=dd610aeda684e42d3933a719cbd59ffbcdfdbcaa;p=thirdparty%2Fgit.git

Merge branch 'kw/patch-ids-optim'

When "git rebase" tries to compare set of changes on the updated
upstream and our own branch, it computes patch-id for all of these
changes and attempts to find matches. This has been optimized by
lazily computing the full patch-id (which is expensive) to be
compared only for changes that touch the same set of paths.

* kw/patch-ids-optim:
  rebase: avoid computing unnecessary patch IDs
  patch-ids: add flag to create the diff patch id using header only data
  patch-ids: replace the seen indicator with a commit pointer
  patch-ids: stop using a hand-rolled hashmap implementation
---

dd610aeda684e42d3933a719cbd59ffbcdfdbcaa
diff --cc diff.c
index b43d3dd2ec,bb816d9cba..534c12e28e
--- a/diff.c
+++ b/diff.c
@@@ -4534,12 -4518,17 +4531,19 @@@ static int diff_get_patch_id(struct dif
  					len2, p->two->path);
  		git_SHA1_Update(&ctx, buffer, len1);
  
+ 		if (diff_header_only)
+ 			continue;
+ 
+ 		if (fill_mmfile(&mf1, p->one) < 0 ||
+ 		    fill_mmfile(&mf2, p->two) < 0)
+ 			return error("unable to read files to diff");
+ 
  		if (diff_filespec_is_binary(p->one) ||
  		    diff_filespec_is_binary(p->two)) {
 -			git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
 -			git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
 +			git_SHA1_Update(&ctx, oid_to_hex(&p->one->oid),
 +					40);
 +			git_SHA1_Update(&ctx, oid_to_hex(&p->two->oid),
 +					40);
  			continue;
  		}