diff mbox series

tree-optimization/116575 - avoid ICE with SLP mask_load_lane

Message ID 20240903072720.B289513A52@imap1.dmz-prg2.suse.org
State New
Headers show
Series tree-optimization/116575 - avoid ICE with SLP mask_load_lane | expand

Commit Message

Richard Biener Sept. 3, 2024, 7:27 a.m. UTC 
The following avoids performing re-discovery with single lanes in
the attempt to for the use of mask_load_lane as rediscovery will
fail since a single lane of a mask load will appear permuted which
isn't supported.

Bootstrap and regtest running on x86_64-unknown-linux-gnu.

	PR tree-optimization/116575
	* tree-vect-slp.cc (vect_analyze_slp): Properly compute
	the mask argument for vect_load/store_lanes_supported.
	When the load is masked for now avoid rediscovery.

	* gcc.dg/vect/pr116575.c: New testcase.
---
 gcc/testsuite/gcc.dg/vect/pr116575.c | 15 +++++++++++++++
 gcc/tree-vect-slp.cc                 | 19 +++++++++++++++++--
 2 files changed, 32 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/vect/pr116575.c
diff mbox series

Patch

diff --git a/gcc/testsuite/gcc.dg/vect/pr116575.c b/gcc/testsuite/gcc.dg/vect/pr116575.c
new file mode 100644
index 00000000000..2047041ca64
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr116575.c
@@ -0,0 +1,15 @@ 
+/* { dg-do compile } */
+
+int a;
+float *b, *c;
+void d(char * __restrict e)
+{
+  for (; a; a++, b += 4, c += 4)
+    if (*e++) {
+	float *f = c;
+	f[0] = b[0];
+	f[1] = b[1];
+	f[2] = b[2];
+	f[3] = b[3];
+    }
+}
diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 2302d91fd23..1342913affa 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -4720,11 +4720,16 @@  vect_analyze_slp (vec_info *vinfo, unsigned max_tree_size)
 		  }
 	    }
 
+	  gimple *rep = STMT_VINFO_STMT (SLP_TREE_REPRESENTATIVE (slp_root));
+	  bool masked = (is_gimple_call (rep)
+			 && gimple_call_internal_p (rep)
+			 && internal_fn_mask_index
+			      (gimple_call_internal_fn (rep)) != -1);
 	  /* If the loads and stores can use load/store-lanes force re-discovery
 	     with single lanes.  */
 	  if (loads_permuted
 	      && !slp_root->ldst_lanes
-	      && vect_store_lanes_supported (vectype, group_size, false)
+	      && vect_store_lanes_supported (vectype, group_size, masked)
 	      != IFN_LAST)
 	    {
 	      bool can_use_lanes = true;
@@ -4734,13 +4739,23 @@  vect_analyze_slp (vec_info *vinfo, unsigned max_tree_size)
 		  {
 		    stmt_vec_info stmt_vinfo = DR_GROUP_FIRST_ELEMENT
 			(SLP_TREE_REPRESENTATIVE (load_node));
+		    rep = STMT_VINFO_STMT (stmt_vinfo);
+		    masked = (is_gimple_call (rep)
+			      && gimple_call_internal_p (rep)
+			      && internal_fn_mask_index
+				   (gimple_call_internal_fn (rep)));
 		    /* Use SLP for strided accesses (or if we can't
 		       load-lanes).  */
 		    if (STMT_VINFO_STRIDED_P (stmt_vinfo)
 			|| compare_step_with_zero (vinfo, stmt_vinfo) <= 0
 			|| vect_load_lanes_supported
 			     (STMT_VINFO_VECTYPE (stmt_vinfo),
-			      DR_GROUP_SIZE (stmt_vinfo), false) == IFN_LAST)
+			      DR_GROUP_SIZE (stmt_vinfo), masked) == IFN_LAST
+			/* ???  During SLP re-discovery with a single lane
+			   a masked grouped load will appear permuted and
+			   discovery will fail.  We have to rework this
+			   on the discovery side - for now avoid ICEing.  */
+			|| masked)
 		      {
 			can_use_lanes = false;
 			break;