From: Richard Biener <rguenther@suse.de>
Date: Tue, 21 May 2024 17:15:33 +0000 (+0200)
Subject: Fix mixed input kind permute optimization
X-Git-Tag: basepoints/gcc-16~8780
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3507ab1b018a68500e49fa9f1de7caa0f1b53dda;p=thirdparty%2Fgcc.git

Fix mixed input kind permute optimization

When change_vec_perm_layout runs into a permute combining two
nodes where one is invariant and one internal the partition of
one input can be -1 but the other might not be.  The following
supports this case by simply ignoring inputs with input partiton -1.

I'm not sure this is correct but it avoids ICEing when accessing
that partitions layout for gcc.target/i386/pr98928.c with the
change to avoid splitting store dataref groups during SLP discovery.

	* tree-vect-slp.cc (change_vec_perm_layout): Ignore an
	input partition of -1.
---

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 43f2c153bf0..3f8209b43a7 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -4640,6 +4640,8 @@ change_vec_perm_layout (slp_tree node, lane_permutation_t &perm,
 	{
 	  slp_tree in_node = SLP_TREE_CHILDREN (node)[entry.first];
 	  unsigned int in_partition_i = m_vertices[in_node->vertex].partition;
+	  if (in_partition_i == -1u)
+	    continue;
 	  this_in_layout_i = m_partitions[in_partition_i].layout;
 	}
       if (this_in_layout_i > 0)