[PATCH] Fix PR91790 by considering different first_stmt_info for realign

As PR91790 exposed, when we have one slp node whose first_stmt_info_for_drptr
is different from first_stmt_info, it's possible that the first_stmt DR isn't
initialized yet before stmt SLP_TREE_SCALAR_STMTS[0] of slp node. So we
shouldn't use first_stmt_info for vect_setup_realignment, instead we can use
the one based on first_stmt_info_for_drptr DR with additional adjustment by
bumping the distance from first_stmt DR.

2019-12-10  Kewen Lin  <linkw@gcc.gnu.org>

  Backport from mainline
  2019-11-27  Kewen Lin  <linkw@gcc.gnu.org>

  PR tree-optimization/91790
  * gcc/tree-vect-stmts.c (vectorizable_load): Use the adjusted DR for
  vect_setup_realignment when first_stmt_info is different from
  first_stmt_info_for_drptr.

From-SVN: r279166
This commit is contained in:
Kewen Lin 2019-12-10 12:54:21 +00:00
parent 92df45de27
commit fdfcc35d8a
2 changed files with 31 additions and 5 deletions

View File

@ -1,3 +1,13 @@
2019-12-10 Kewen Lin <linkw@gcc.gnu.org>
Backport from mainline
2019-11-27 Kewen Lin <linkw@gcc.gnu.org>
PR tree-optimization/91790
* gcc/tree-vect-stmts.c (vectorizable_load): Use the adjusted DR for
vect_setup_realignment when first_stmt_info is different from
first_stmt_info_for_drptr.
2019-12-09 Eric Botcazou <ebotcazou@adacore.com>
* tree.c (build_array_type_1): Add SET_CANONICAL parameter and compute

View File

@ -8272,18 +8272,27 @@ vectorizable_load (stmt_vec_info stmt_info, gimple_stmt_iterator *gsi,
compute_in_loop = true;
}
bool diff_first_stmt_info
= first_stmt_info_for_drptr && first_stmt_info != first_stmt_info_for_drptr;
if ((alignment_support_scheme == dr_explicit_realign_optimized
|| alignment_support_scheme == dr_explicit_realign)
&& !compute_in_loop)
{
msq = vect_setup_realignment (first_stmt_info, gsi, &realignment_token,
alignment_support_scheme, NULL_TREE,
&at_loop);
/* If we have different first_stmt_info, we can't set up realignment
here, since we can't guarantee first_stmt_info DR has been
initialized yet, use first_stmt_info_for_drptr DR by bumping the
distance from first_stmt_info DR instead as below. */
if (!diff_first_stmt_info)
msq = vect_setup_realignment (first_stmt_info, gsi, &realignment_token,
alignment_support_scheme, NULL_TREE,
&at_loop);
if (alignment_support_scheme == dr_explicit_realign_optimized)
{
phi = as_a <gphi *> (SSA_NAME_DEF_STMT (msq));
byte_offset = size_binop (MINUS_EXPR, TYPE_SIZE_UNIT (vectype),
size_one_node);
gcc_assert (!first_stmt_info_for_drptr);
}
}
else
@ -8339,8 +8348,7 @@ vectorizable_load (stmt_vec_info stmt_info, gimple_stmt_iterator *gsi,
dataref_ptr = unshare_expr (DR_BASE_ADDRESS (first_dr_info->dr));
dataref_offset = build_int_cst (ref_type, 0);
}
else if (first_stmt_info_for_drptr
&& first_stmt_info != first_stmt_info_for_drptr)
else if (diff_first_stmt_info)
{
dataref_ptr
= vect_create_data_ref_ptr (first_stmt_info_for_drptr,
@ -8357,6 +8365,14 @@ vectorizable_load (stmt_vec_info stmt_info, gimple_stmt_iterator *gsi,
DR_INIT (ptrdr)));
dataref_ptr = bump_vector_ptr (dataref_ptr, ptr_incr, gsi,
stmt_info, diff);
if (alignment_support_scheme == dr_explicit_realign)
{
msq = vect_setup_realignment (first_stmt_info_for_drptr, gsi,
&realignment_token,
alignment_support_scheme,
dataref_ptr, &at_loop);
gcc_assert (!compute_in_loop);
}
}
else if (STMT_VINFO_GATHER_SCATTER_P (stmt_info))
vect_get_gather_scatter_ops (loop, stmt_info, &gs_info,