middle-end: Move load/store-lanes check till late.

This moves the code that checks for load/store lanes further in the pipeline and
places it after slp_optimize.  This would allow us to perform optimizations on
the SLP tree and only bail out if we really have a permute.

With this change it allows us to handle permutes such as {1,1,1,1} which should
be handled by a load and replicate.

This change however makes it all or nothing. Either all instances can be handled
or none at all.  This is why some of the test cases have been adjusted.

gcc/ChangeLog:

	* tree-vect-slp.c (vect_analyze_slp_instance): Moved load/store lanes
	check to ...
	* tree-vect-loop.c (vect_analyze_loop_2): ..Here

gcc/testsuite/ChangeLog:

	* gcc.dg/vect/slp-11b.c: Update output scan.
	* gcc.dg/vect/slp-perm-6.c: Likewise.
This commit is contained in:
Tamar Christina 2020-11-04 22:33:11 +00:00
parent 6682ef4363
commit 4d76079fdf
4 changed files with 77 additions and 53 deletions

View File

@ -45,4 +45,4 @@ int main (void)
/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" { target { vect_strided4 && vect_int_mult } } } } */
/* { dg-final { scan-tree-dump-times "vectorized 0 loops" 1 "vect" { target { ! { vect_strided4 && vect_int_mult } } } } } */
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 0 "vect" } } */
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 1 "vect" } } */

View File

@ -106,7 +106,7 @@ int main (int argc, const char* argv[])
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 2 "vect" { target { vect_perm3_int && { {! vect_load_lanes } && {! vect_partial_vectors_usage_1 } } } } } } */
/* The epilogues are vectorized using partial vectors. */
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 4 "vect" { target { vect_perm3_int && { {! vect_load_lanes } && vect_partial_vectors_usage_1 } } } } } */
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 1 "vect" { target vect_load_lanes } } } */
/* { dg-final { scan-tree-dump "Built SLP cancelled: can use load/store-lanes" "vect" { target { vect_perm3_int && vect_load_lanes } } } } */
/* { dg-final { scan-tree-dump "LOAD_LANES" "vect" { target vect_load_lanes } } } */
/* { dg-final { scan-tree-dump "STORE_LANES" "vect" { target vect_load_lanes } } } */
/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 2 "vect" { target vect_load_lanes } } } */
/* { dg-final { scan-tree-dump "Built SLP cancelled: can use load/store-lanes" "vect" { xfail { vect_perm3_int && vect_load_lanes } } } } */
/* { dg-final { scan-tree-dump "LOAD_LANES" "vect" { xfail vect_load_lanes } } } */
/* { dg-final { scan-tree-dump "STORE_LANES" "vect" { xfail vect_load_lanes } } } */

View File

@ -2365,6 +2365,78 @@ start_over:
"unsupported SLP instances\n");
goto again;
}
/* Check whether any load in ALL SLP instances is possibly permuted. */
slp_tree load_node, slp_root;
unsigned i, x;
slp_instance instance;
bool can_use_lanes = true;
FOR_EACH_VEC_ELT (LOOP_VINFO_SLP_INSTANCES (loop_vinfo), x, instance)
{
slp_root = SLP_INSTANCE_TREE (instance);
int group_size = SLP_TREE_LANES (slp_root);
tree vectype = SLP_TREE_VECTYPE (slp_root);
bool loads_permuted = false;
FOR_EACH_VEC_ELT (SLP_INSTANCE_LOADS (instance), i, load_node)
{
if (!SLP_TREE_LOAD_PERMUTATION (load_node).exists ())
continue;
unsigned j;
stmt_vec_info load_info;
FOR_EACH_VEC_ELT (SLP_TREE_SCALAR_STMTS (load_node), j, load_info)
if (SLP_TREE_LOAD_PERMUTATION (load_node)[j] != j)
{
loads_permuted = true;
break;
}
}
/* If the loads and stores can be handled with load/store-lane
instructions record it and move on to the next instance. */
if (loads_permuted
&& vect_store_lanes_supported (vectype, group_size, false))
{
FOR_EACH_VEC_ELT (SLP_INSTANCE_LOADS (instance), i, load_node)
{
stmt_vec_info stmt_vinfo = DR_GROUP_FIRST_ELEMENT
(SLP_TREE_SCALAR_STMTS (load_node)[0]);
/* Use SLP for strided accesses (or if we can't
load-lanes). */
if (STMT_VINFO_STRIDED_P (stmt_vinfo)
|| ! vect_load_lanes_supported
(STMT_VINFO_VECTYPE (stmt_vinfo),
DR_GROUP_SIZE (stmt_vinfo), false))
break;
}
can_use_lanes
= can_use_lanes && i == SLP_INSTANCE_LOADS (instance).length ();
if (can_use_lanes && dump_enabled_p ())
dump_printf_loc (MSG_NOTE, vect_location,
"SLP instance %p can use load/store-lanes\n",
instance);
}
else
{
can_use_lanes = false;
break;
}
}
/* If all SLP instances can use load/store-lanes abort SLP and try again
with SLP disabled. */
if (can_use_lanes)
{
ok = opt_result::failure_at (vect_location,
"Built SLP cancelled: can use "
"load/store-lanes\n");
if (dump_enabled_p ())
dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
"Built SLP cancelled: all SLP instances support "
"load/store-lanes\n");
goto again;
}
}
/* Dissolve SLP-only groups. */

View File

@ -2263,54 +2263,6 @@ vect_build_slp_instance (vec_info *vinfo,
"SLP size %u vs. limit %u.\n",
tree_size, max_tree_size);
/* Check whether any load is possibly permuted. */
slp_tree load_node;
bool loads_permuted = false;
FOR_EACH_VEC_ELT (SLP_INSTANCE_LOADS (new_instance), i, load_node)
{
if (!SLP_TREE_LOAD_PERMUTATION (load_node).exists ())
continue;
unsigned j;
stmt_vec_info load_info;
FOR_EACH_VEC_ELT (SLP_TREE_SCALAR_STMTS (load_node), j, load_info)
if (SLP_TREE_LOAD_PERMUTATION (load_node)[j] != j)
{
loads_permuted = true;
break;
}
}
/* If the loads and stores can be handled with load/store-lane
instructions do not generate this SLP instance. */
if (is_a <loop_vec_info> (vinfo)
&& loads_permuted
&& kind == slp_inst_kind_store
&& vect_store_lanes_supported
(STMT_VINFO_VECTYPE (scalar_stmts[0]), group_size, false))
{
slp_tree load_node;
FOR_EACH_VEC_ELT (SLP_INSTANCE_LOADS (new_instance), i, load_node)
{
stmt_vec_info stmt_vinfo = DR_GROUP_FIRST_ELEMENT
(SLP_TREE_SCALAR_STMTS (load_node)[0]);
/* Use SLP for strided accesses (or if we can't load-lanes). */
if (STMT_VINFO_STRIDED_P (stmt_vinfo)
|| ! vect_load_lanes_supported
(STMT_VINFO_VECTYPE (stmt_vinfo),
DR_GROUP_SIZE (stmt_vinfo), false))
break;
}
if (i == SLP_INSTANCE_LOADS (new_instance).length ())
{
if (dump_enabled_p ())
dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
"Built SLP cancelled: can use "
"load/store-lanes\n");
vect_free_slp_instance (new_instance);
return false;
}
}
/* Fixup SLP reduction chains. */
if (kind == slp_inst_kind_reduc_chain)
{