On Fri, May 6, 2011 at 10:24 PM, Jan Hubicka <hubi...@ucw.cz> wrote:
> Hi,
> while looking at type merging code I noticed that type pairs can be managed
> to be ordered by their UIDs. This save some of hashing overhead in one of
> most intensively querried hashes.
>
> Also gimple_lookup_type_leader is hot function that is better to be inlined.
>
> I also wonder, why unionfind algorithm is not used here to maintain the
> positive answers?
Can you elaborate?
> Bootstrapped/regtested x86_64-linux, OK?
Ok.
Thanks,
Richard.
> Honza
>
> * gimple.c (type_pair_hash, type_pair_eq, lookup_type_pair):
> Arrange type pairs to be UID ordered.
> (gimple_lookup_type_leader): Make inline.
> Index: gimple.c
> ===================================================================
> --- gimple.c (revision 173506)
> +++ gimple.c (working copy)
> @@ -3240,8 +3240,7 @@ type_pair_hash (const void *p)
> const struct type_pair_d *pair = (const struct type_pair_d *) p;
> hashval_t val1 = pair->uid1;
> hashval_t val2 = pair->uid2;
> - return (iterative_hash_hashval_t (val2, val1)
> - ^ iterative_hash_hashval_t (val1, val2));
> + return iterative_hash_hashval_t (val1, val2);
> }
>
> /* Compare two type pairs pointed-to by P1 and P2. */
> @@ -3251,8 +3250,7 @@ type_pair_eq (const void *p1, const void
> {
> const struct type_pair_d *pair1 = (const struct type_pair_d *) p1;
> const struct type_pair_d *pair2 = (const struct type_pair_d *) p2;
> - return ((pair1->uid1 == pair2->uid1 && pair1->uid2 == pair2->uid2)
> - || (pair1->uid1 == pair2->uid2 && pair1->uid2 == pair2->uid1));
> + return (pair1->uid1 == pair2->uid1 && pair1->uid2 == pair2->uid2);
> }
>
> /* Lookup the pair of types T1 and T2 in *VISITED_P. Insert a new
> @@ -3271,8 +3269,16 @@ lookup_type_pair (tree t1, tree t2, htab
> gcc_obstack_init (ob_p);
> }
>
> - pair.uid1 = TYPE_UID (t1);
> - pair.uid2 = TYPE_UID (t2);
> + if (TYPE_UID (t1) < TYPE_UID (t2))
> + {
> + pair.uid1 = TYPE_UID (t1);
> + pair.uid2 = TYPE_UID (t2);
> + }
> + else
> + {
> + pair.uid1 = TYPE_UID (t2);
> + pair.uid2 = TYPE_UID (t1);
> + }
> slot = htab_find_slot (*visited_p, &pair, INSERT);
>
> if (*slot)
> @@ -3280,8 +3286,8 @@ lookup_type_pair (tree t1, tree t2, htab
> else
> {
> p = XOBNEW (ob_p, struct type_pair_d);
> - p->uid1 = TYPE_UID (t1);
> - p->uid2 = TYPE_UID (t2);
> + p->uid1 = pair.uid1;
> + p->uid2 = pair.uid2;
> p->same_p[0] = -2;
> p->same_p[1] = -2;
> *slot = (void *) p;
> @@ -3324,7 +3330,7 @@ static GTY((deletable, length("GIMPLE_TY
> /* Lookup an existing leader for T and return it or NULL_TREE, if
> there is none in the cache. */
>
> -static tree
> +static inline tree
> gimple_lookup_type_leader (tree t)
> {
> gimple_type_leader_entry *leader;
>
