[gcc r12-9482] PR tree-optimization/109392

[gcc r12-9482] PR tree-optimization/109392

[Richard Biener]

https://gcc.gnu.org/g:d639236ea87ff8a6a2d56c0408e6eb92674418e6

commit r12-9482-gd639236ea87ff8a6a2d56c0408e6eb92674418e6
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Apr 8 12:21:42 2023 -0600

    PR tree-optimization/109392
    
    If we have an object with SSA_NAME_OCCURS_IN_ABNORMAL_PHI, then
    maybe_push_res_to_seq may fail.  Directly build the extraction
    for that case.
    
            PR tree-optimization/109392
    
    gcc/
            * tree-vect-generic.cc (tree_vec_extract): Handle failure
            of maybe_push_res_to_seq better.
    
    gcc/testsuite/
    
            * gcc.dg/pr109392.c: New test.
    
    (cherry picked from commit 101380a8394c22a7a2ea70de2060ee93716156e2)

Diff:
---
 gcc/testsuite/gcc.dg/pr109392.c | 15 +++++++++++++++
 gcc/tree-vect-generic.cc        | 11 ++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/gcc/testsuite/gcc.dg/pr109392.c b/gcc/testsuite/gcc.dg/pr109392.c
new file mode 100644
index 00000000000..e5bd9d440fa
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr109392.c
@@ -0,0 +1,15 @@
+/* PR tree-optimization/109392 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wno-psabi" } */
+
+typedef short __attribute__ ((__vector_size__ (64))) V;
+V v, w;
+void bar (void) __attribute__((returns_twice));
+
+V
+foo (V a, V b)
+{
+  bar ();
+  b &= v < b;
+  return (V) { foo (b, w)[3], (V) {}[3] };
+}
diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc
index a84f5e4ca78..f282e69d53b 100644
--- a/gcc/tree-vect-generic.cc
+++ b/gcc/tree-vect-generic.cc
@@ -183,7 +183,16 @@ tree_vec_extract (gimple_stmt_iterator *gsi, tree type,
   opr.resimplify (NULL, follow_all_ssa_edges);
   gimple_seq stmts = NULL;
   tree res = maybe_push_res_to_seq (&opr, &stmts);
-  gcc_assert (res);
+  if (!res)
+    {
+      /* This can happen if SSA_NAME_OCCURS_IN_ABNORMAL_PHI are
+	 used.  Build BIT_FIELD_REF manually otherwise.  */
+      t = build3 (BIT_FIELD_REF, type, t, bitsize, bitpos);
+      res = make_ssa_name (type);
+      gimple *g = gimple_build_assign (res, t);
+      gsi_insert_before (gsi, g, GSI_SAME_STMT);
+      return res;
+    }
   gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
   return res;
 }