mirror/hdf5
2
0
Fork 0
mirror of https://github.com/HDFGroup/hdf5.git synced 2025-04-06 17:20:42 +08:00
Code Issues Packages Projects Releases Wiki Activity

[svn-r8135] Purpose:

Browse Source 
Optimization

Description:
    Speed up core ID lookup routine (H5I_find_id) by re-structuring the logic
to reduce the number of 'if' statements.

Platforms tested:
    IBM p690 (copper)
    too minor to require h5committest
This commit is contained in:
Quincey Koziol 2004-01-31 10:21:17 -05:00
parent 10382a1799
commit eb4cc0556c
1 changed files with 11 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
src/H5I.c
View File

@ -1345,33 +1345,29 @@ H5I_find_id(hid_t id)
/* Check arguments */
grp = H5I_GRP(id);
if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, NULL, "invalid group number");
assert(grp > H5I_BADID && grp < H5I_NGROUPS);
grp_ptr = H5I_id_group_list_g[grp];
if (grp_ptr == NULL || grp_ptr->count <= 0)
HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, NULL, "invalid group");
assert(grp_ptr && grp_ptr->count > 0);
/* Get the bucket in which the ID is located */
hash_loc = (unsigned)H5I_LOC(id, grp_ptr->hash_size);
id_ptr = grp_ptr->id_list[hash_loc];
if (id_ptr == NULL)
HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, NULL, "invalid ID");
/* Scan the bucket's linked list for a match */
last_id=NULL;
while (id_ptr) {
if (id_ptr->id == id)
if (id_ptr->id == id) {
/* If we found an object, move it to the front of the list, if it isn't there already */
if(last_id!=NULL) {
last_id->next=id_ptr->next;
id_ptr->next=grp_ptr->id_list[hash_loc];
grp_ptr->id_list[hash_loc]=id_ptr;
} /* end if */
break;
} /* end if */
last_id=id_ptr;
id_ptr = id_ptr->next;
}
/* If we found an object, move it to the front of the list, if it isn't there already */
if(id_ptr!=NULL && last_id!=NULL) {
last_id->next=id_ptr->next;
id_ptr->next=grp_ptr->id_list[hash_loc];
grp_ptr->id_list[hash_loc]=id_ptr;
} /* end if */
} /* end while */
/* Set the return value */
ret_value = id_ptr;