backport: re PR rtl-optimization/79901 (ICE in prepare_cmp_insn, at optabs.c:3904)

	Backported from mainline
	2017-03-07  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/79901
	* expr.c (expand_expr_real_2): For vector MIN/MAX, if there is no
	min/max expander, expand it using expand_vec_cond_expr.

From-SVN: r248654

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 67739ea67bad3e2dab6fe834b3412d510bfeb856..6eb34c77a833c702a8681f7afb9a0bd5e35d0857 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,12 @@
 2017-05-30  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2017-03-07  Jakub Jelinek  <jakub@redhat.com>
+
+       PR rtl-optimization/79901
+       * expr.c (expand_expr_real_2): For vector MIN/MAX, if there is no
+       min/max expander, expand it using expand_vec_cond_expr.
+
        2017-03-03  Jakub Jelinek  <jakub@redhat.com>
 
        PR target/79807

diff --git a/gcc/expr.c b/gcc/expr.c
index e92d781e3949dc21fec2d76e05238ede04b4d529..164f9e9c26c7b153be68fffad213183e13ca65ef 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -8852,6 +8852,18 @@ expand_expr_real_2 (sepops ops, rtx target, machine_mode tmode,
       if (temp != 0)
        return temp;
 
+      /* For vector MIN <x, y>, expand it a VEC_COND_EXPR <x <= y, x, y>
+        and similarly for MAX <x, y>.  */
+      if (VECTOR_TYPE_P (type))
+       {
+         tree t0 = make_tree (type, op0);
+         tree t1 = make_tree (type, op1);
+         tree comparison = build2 (code == MIN_EXPR ? LE_EXPR : GE_EXPR,
+                                   type, t0, t1);
+         return expand_vec_cond_expr (type, comparison, t0, t1,
+                                      original_target);
+       }
+
       /* At this point, a MEM target is no longer useful; we will get better
         code without it.  */