The following removes a FIXME where we fail(ed) to keep virtual
SSA up-to-date, patching up the remaining two cases I managed to
trigger. I've left an assert so that we pick up cases arising
for the cases I wasn't able to trigger.
Bootstrapped and tested on x86_64-unknown-linux-gnu, I've also
built SPEC CPU 2017 with and without LTO and zen2 arch.
I eventually do expect fallout, so sorry for that in advance.
Pushed to trunk.
Richard.
2022-07-04 Richard Biener <rguent...@suse.de>
* tree-vect-loop-manip.cc (vect_do_peeling): Assert that
no SSA update is needed instead of updating virtual SSA
form.
* tree-vect-stmts.cc (vectorizable_load): For hoisted
invariant load use the loop entry virtual use.
For emulated gather loads use the virtual use of the
original stmt like vect_finish_stmt_generation would do.
---
gcc/tree-vect-loop-manip.cc | 11 ++++-------
gcc/tree-vect-stmts.cc | 15 ++++++++++++---
2 files changed, 16 insertions(+), 10 deletions(-)
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index ae5533e0f68..81e29d564d6 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -2683,14 +2683,11 @@ vect_do_peeling (loop_vec_info loop_vinfo, tree niters,
tree nitersm1,
class loop *first_loop = loop;
bool irred_flag = loop_preheader_edge (loop)->flags & EDGE_IRREDUCIBLE_LOOP;
- /* We might have a queued need to update virtual SSA form. As we
- delete the update SSA machinery below after doing a regular
+ /* Historically we might have a queued need to update virtual SSA form.
+ As we delete the update SSA machinery below after doing a regular
incremental SSA update during loop copying make sure we don't
- lose that fact.
- ??? Needing to update virtual SSA form by renaming is unfortunate
- but not all of the vectorizer code inserting new loads / stores
- properly assigns virtual operands to those statements. */
- update_ssa (TODO_update_ssa_only_virtuals);
+ lose that fact. */
+ gcc_assert (!need_ssa_update_p (cfun));
create_lcssa_for_virtual_phi (loop);
diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index 346d8ce2804..d6a6fe3fb38 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -9024,9 +9024,16 @@ vectorizable_load (vec_info *vinfo,
"hoisting out of the vectorized loop: %G", stmt);
scalar_dest = copy_ssa_name (scalar_dest);
tree rhs = unshare_expr (gimple_assign_rhs1 (stmt));
- gsi_insert_on_edge_immediate
- (loop_preheader_edge (loop),
- gimple_build_assign (scalar_dest, rhs));
+ edge pe = loop_preheader_edge (loop);
+ gphi *vphi = get_virtual_phi (loop->header);
+ tree vuse;
+ if (vphi)
+ vuse = PHI_ARG_DEF_FROM_EDGE (vphi, pe);
+ else
+ vuse = gimple_vuse (gsi_stmt (*gsi));
+ gimple *new_stmt = gimple_build_assign (scalar_dest, rhs);
+ gimple_set_vuse (new_stmt, vuse);
+ gsi_insert_on_edge_immediate (pe, new_stmt);
}
/* These copies are all equivalent, but currently the representation
requires a separate STMT_VINFO_VEC_STMT for each one. */
@@ -9769,6 +9776,8 @@ vectorizable_load (vec_info *vinfo,
tree ref = build2 (MEM_REF, ltype, ptr,
build_int_cst (ref_type, 0));
new_stmt = gimple_build_assign (elt, ref);
+ gimple_set_vuse (new_stmt,
+ gimple_vuse (gsi_stmt (*gsi)));
gimple_seq_add_stmt (&stmts, new_stmt);
CONSTRUCTOR_APPEND_ELT (ctor_elts, NULL_TREE, elt);
}
--
2.35.3
