[PATCH PR81799]Fix ICE by forcing to is_gimple_val

[Bin Cheng]

Hi,
This patch fixes ICE reported in PR81799.  It simply uses is_gimple_val rather 
than is_gimple_condexpr.
Bootstap and test on x86_64.  Is it OK?

Thanks,
bin
2017-08-11  Bin Cheng  <bin.ch...@arm.com>

        PR tree-optimization/81799
        * tree-loop-distribution.c (version_loop_by_alias_check): Force
        cond_expr to simple gimple operand.

gcc/testsuite
2017-08-11  Bin Cheng  <bin.ch...@arm.com>

        PR tree-optimization/81799
        * gcc.dg/tree-ssa/pr81799.c: New.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr81799.c 
b/gcc/testsuite/gcc.dg/tree-ssa/pr81799.c
new file mode 100644
index 0000000..aad01232
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr81799.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+int printf (const char *, ...);
+
+int a, c[1], d, e, **f;
+
+void fn1 (int h)
+{
+  int *i = 0;
+  for (d = 0; d < 1; d++)
+    {
+      if (d)
+        continue;
+      for (; e; e++)
+        {
+          a = c[*i];
+          if (h)
+            printf ("0");
+        }
+      return;
+    }
+  f = &i;
+}
+
diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index 8d80ccc..b1b2934 100644
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -2263,7 +2263,7 @@ version_loop_by_alias_check (struct loop *loop, 
vec<ddr_p> *alias_ddrs)
   compute_alias_check_pairs (loop, alias_ddrs, &comp_alias_pairs);
   create_runtime_alias_checks (loop, &comp_alias_pairs, &cond_expr);
   cond_expr = force_gimple_operand_1 (cond_expr, &cond_stmts,
-                                     is_gimple_condexpr, NULL_TREE);
+                                     is_gimple_val, NULL_TREE);
 
   /* Depend on vectorizer to fold IFN_LOOP_DIST_ALIAS.  */
   if (flag_tree_loop_vectorize)