pack-objects: move in_pack_pos out of struct object_entry

This field is only need for pack-bitmap, which is an optional
feature. Move it to a separate array that is only allocated when
pack-bitmap is used (like objects[], it is not freed, since we need it
until the end of the process)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/pack-objects.c

@@ -879,7 +879,8 @@ static void write_pack_file(void)
 
 			if (write_bitmap_index) {
 				bitmap_writer_set_checksum(oid.hash);
-				bitmap_writer_build_type_index(written_list, nr_written);
+				bitmap_writer_build_type_index(
+					&to_pack, written_list, nr_written);
 			}
 
 			finish_tmp_packfile(&tmpname, pack_tmp_name,

pack-bitmap-write.c

@@ -48,7 +48,8 @@ void bitmap_writer_show_progress(int show)
 /**
  * Build the initial type index for the packfile
  */
-void bitmap_writer_build_type_index(struct pack_idx_entry **index,
+void bitmap_writer_build_type_index(struct packing_data *to_pack,
+				    struct pack_idx_entry **index,
 				    uint32_t index_nr)
 {
 	uint32_t i;
@@ -57,12 +58,13 @@ void bitmap_writer_build_type_index(struct pack_idx_entry **index,
 	writer.trees = ewah_new();
 	writer.blobs = ewah_new();
 	writer.tags = ewah_new();
+	ALLOC_ARRAY(to_pack->in_pack_pos, to_pack->nr_objects);
 
 	for (i = 0; i < index_nr; ++i) {
 		struct object_entry *entry = (struct object_entry *)index[i];
 		enum object_type real_type;
 
-		entry->in_pack_pos = i;
+		oe_set_in_pack_pos(to_pack, entry, i);
 
 		switch (oe_type(entry)) {
 		case OBJ_COMMIT:
@@ -146,7 +148,7 @@ static uint32_t find_object_pos(const unsigned char *sha1)
 			"(object %s is missing)", sha1_to_hex(sha1));
 	}
 
-	return entry->in_pack_pos;
+	return oe_in_pack_pos(writer.to_pack, entry);
 }
 
 static void show_object(struct object *object, const char *name, void *data)

pack-bitmap.c

@@ -1033,7 +1033,7 @@ int rebuild_existing_bitmaps(struct packing_data *mapping,
 		oe = packlist_find(mapping, sha1, NULL);
 
 		if (oe)
-			reposition[i] = oe->in_pack_pos + 1;
+			reposition[i] = oe_in_pack_pos(mapping, oe) + 1;
 	}
 
 	rebuild = bitmap_new();

pack-bitmap.h

@@ -44,7 +44,9 @@ int rebuild_existing_bitmaps(struct packing_data *mapping, khash_sha1 *reused_bi
 
 void bitmap_writer_show_progress(int show);
 void bitmap_writer_set_checksum(unsigned char *sha1);
-void bitmap_writer_build_type_index(struct pack_idx_entry **index, uint32_t index_nr);
+void bitmap_writer_build_type_index(struct packing_data *to_pack,
+				    struct pack_idx_entry **index,
+				    uint32_t index_nr);
 void bitmap_writer_reuse_bitmaps(struct packing_data *to_pack);
 void bitmap_writer_select_commits(struct commit **indexed_commits,
 		unsigned int indexed_commits_nr, int max_bitmaps);

pack-objects.h

@@ -79,7 +79,6 @@ struct object_entry {
 	unsigned in_pack_type:TYPE_BITS; /* could be delta */
 	unsigned type_valid:1;
 	uint32_t hash;			/* name hint hash */
-	unsigned int in_pack_pos;
 	unsigned char in_pack_header_size;
 	unsigned preferred_base:1; /*
 				    * we do not pack this, but is available
@@ -99,6 +98,8 @@ struct packing_data {
 
 	int32_t *index;
 	uint32_t index_size;
+
+	unsigned int *in_pack_pos;
 };
 
 struct object_entry *packlist_alloc(struct packing_data *pdata,
@@ -144,4 +145,17 @@ static inline void oe_set_type(struct object_entry *e,
 	e->type_ = (unsigned)type;
 }
 
+static inline unsigned int oe_in_pack_pos(const struct packing_data *pack,
+					  const struct object_entry *e)
+{
+	return pack->in_pack_pos[e - pack->objects];
+}
+
+static inline void oe_set_in_pack_pos(const struct packing_data *pack,
+				      const struct object_entry *e,
+				      unsigned int pos)
+{
+	pack->in_pack_pos[e - pack->objects] = pos;
+}
+
 #endif