From: Richard Biener <rguenther@suse.de>
Date: Tue, 6 Apr 2021 09:21:47 +0000 (+0200)
Subject: tree-optimization/99924 - visit permute nodes again when partitioning
X-Git-Tag: basepoints/gcc-12~256
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=58cd9fc8a61de09ba181c5ed5ac7fb91ec506414;p=thirdparty%2Fgcc.git

tree-optimization/99924 - visit permute nodes again when partitioning

Since SLP graph partitioning works on scalar stmts (because it's done
for costing) we have to make sure to visit permute nodes multiple
times since they will not pull partitions together.

2021-04-06  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/99924
	* tree-vect-slp.c (vect_bb_partition_graph_r): Do not mark
	nodes w/o scalar stmts as visited.

	* gfortran.dg/vect/pr99924.f90: New testcase.
---

diff --git a/gcc/testsuite/gfortran.dg/vect/pr99924.f90 b/gcc/testsuite/gfortran.dg/vect/pr99924.f90
new file mode 100644
index 000000000000..f271ea1d0d56
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/vect/pr99924.f90
@@ -0,0 +1,12 @@
+! { dg-do compile }
+! { dg-additional-options "-march=armv8.3-a" { target aarch64-*-* } }
+subroutine cunhj (tfn, asum, bsum)
+  implicit none
+  complex :: up, tfn, asum, bsum
+  real :: ar
+
+  up = tfn * ar
+  bsum = up + ar
+  asum = up + asum
+  return
+end subroutine cunhj
diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c
index ceec7f5c4109..58dedfc35b71 100644
--- a/gcc/tree-vect-slp.c
+++ b/gcc/tree-vect-slp.c
@@ -4224,7 +4224,7 @@ vect_bb_partition_graph_r (bb_vec_info bb_vinfo,
       stmt_instance = instance;
     }
 
-  if (visited.add (node))
+  if (!SLP_TREE_SCALAR_STMTS (node).is_empty () && visited.add (node))
     return;
 
   slp_tree child;