[PATCH] tree-optimization/115537 - ICE with SLP condition reduction vectorization

[Richard Biener]

The condition rejecting "multiple-type" SLP condition reduction lacks
handling EXTRACT_LAST reductions.

Bootstrap and regtest in progress on x86_64-unknown-linux-gnu.

Richard.

        PR tree-optimization/115537
        * tree-vect-loop.cc (vectorizable_reduction): Also reject
        SLP condition reductions of EXTRACT_LAST kind when multiple
        statement copies are involved.

        * gcc.dg/vect/pr115537.c: New testcase.
---
 gcc/testsuite/gcc.dg/vect/pr115537.c | 19 +++++++++++++++++++
 gcc/tree-vect-loop.cc                |  5 +++--
 2 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/vect/pr115537.c

diff --git a/gcc/testsuite/gcc.dg/vect/pr115537.c 
b/gcc/testsuite/gcc.dg/vect/pr115537.c
new file mode 100644
index 00000000000..99ed467feb8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr115537.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-mcpu=neoverse-n1" { target aarch64*-*-* } } */
+
+char *a;
+int b;
+void c()
+{
+  int d = 0, e = 0, f;
+  for (; f; ++f)
+    if (a[f] == 5)
+      ;
+    else if (a[f])
+      e = 1;
+    else
+      d = 1;
+  if (d)
+    if (e)
+      b = 0;
+}
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 7c79e9da106..eeb75c09e91 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -8083,13 +8083,14 @@ vectorizable_reduction (loop_vec_info loop_vinfo,
 
   if ((reduction_type == COND_REDUCTION
        || reduction_type == INTEGER_INDUC_COND_REDUCTION
-       || reduction_type == CONST_COND_REDUCTION)
+       || reduction_type == CONST_COND_REDUCTION
+       || reduction_type == EXTRACT_LAST_REDUCTION)
       && slp_node
       && SLP_TREE_NUMBER_OF_VEC_STMTS (slp_node) > 1)
     {
       if (dump_enabled_p ())
        dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
-                        "multiple types in condition reduction reduction.\n");
+                        "multiple types in condition reduction.\n");
       return false;
     }
 
-- 
2.35.3