[PATCH 1/3] Use cvt_op to save intermediate type operand instead of "subtle" vec_dest.

[liuhongt via Gcc-patches]

When there're multiple operands in vec_oprnds0, vec_dest will be
overwrited to vectype_out, but in multi_step_cvt case, cvt_type is
expected. It caused an ICE when verify_gimple_in_cfg.

Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,} and aarch64-linux-gnu.
Ok for trunk?

gcc/ChangeLog:

        PR tree-optimization/110371
        PR tree-optimization/110018
        * tree-vect-stmts.cc (vectorizable_conversion): Use cvt_op to
        save intermediate type operand instead of "subtle" vec_dest
        for case NONE.

gcc/testsuite/ChangeLog:

        * gcc.target/aarch64/pr110371.c: New test.
---
 gcc/testsuite/gcc.target/aarch64/pr110371.c | 20 ++++++++++++++++++++
 gcc/tree-vect-stmts.cc                      | 14 ++++++++++----
 2 files changed, 30 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/aarch64/pr110371.c

diff --git a/gcc/testsuite/gcc.target/aarch64/pr110371.c 
b/gcc/testsuite/gcc.target/aarch64/pr110371.c
new file mode 100644
index 00000000000..444e514e04f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr110371.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+typedef struct dest
+{
+  double m[3][3];
+} dest;
+
+typedef struct src
+{
+  int m[3][3];
+} src;
+
+void
+foo (dest *a, src* s)
+{
+  for (int i = 0; i != 3; i++)
+    for (int j = 0; j != 3; j++)
+      a->m[i][j] = s->m[i][j];
+}
diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index 85d1f3ae52c..1748555a625 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -5044,7 +5044,7 @@ vectorizable_conversion (vec_info *vinfo,
                         gimple **vec_stmt, slp_tree slp_node,
                         stmt_vector_for_cost *cost_vec)
 {
-  tree vec_dest;
+  tree vec_dest, cvt_op = NULL_TREE;
   tree scalar_dest;
   tree op0, op1 = NULL_TREE;
   loop_vec_info loop_vinfo = dyn_cast <loop_vec_info> (vinfo);
@@ -5568,6 +5568,13 @@ vectorizable_conversion (vec_info *vinfo,
     case NONE:
       vect_get_vec_defs (vinfo, stmt_info, slp_node, ncopies,
                         op0, &vec_oprnds0);
+      /* vec_dest is intermediate type operand when multi_step_cvt.  */
+      if (multi_step_cvt)
+       {
+         cvt_op = vec_dest;
+         vec_dest = vec_dsts[0];
+       }
+
       FOR_EACH_VEC_ELT (vec_oprnds0, i, vop0)
        {
          /* Arguments are ready, create the new vector stmt.  */
@@ -5575,12 +5582,11 @@ vectorizable_conversion (vec_info *vinfo,
          if (multi_step_cvt)
            {
              gcc_assert (multi_step_cvt == 1);
-             new_stmt = vect_gimple_build (vec_dest, codecvt1, vop0);
-             new_temp = make_ssa_name (vec_dest, new_stmt);
+             new_stmt = vect_gimple_build (cvt_op, codecvt1, vop0);
+             new_temp = make_ssa_name (cvt_op, new_stmt);
              gimple_assign_set_lhs (new_stmt, new_temp);
              vect_finish_stmt_generation (vinfo, stmt_info, new_stmt, gsi);
              vop0 = new_temp;
-             vec_dest = vec_dsts[0];
            }
          new_stmt = vect_gimple_build (vec_dest, code1, vop0);
          new_temp = make_ssa_name (vec_dest, new_stmt);
-- 
2.39.1.388.g2fc9e9ca3c