[PATCH, PR tree-optimization/PR68305] Support masked COND_EXPR in SLP

[Ilya Enkovich]

Hi,

This patch fixes a way operand is chosen by its num for COND_EXPR.  
Bootstrapped and regtested on x86_64-unknown-linux-gnu.  OK for trunk?

Thanks,
Ilya
--
gcc/

2015-11-12  Ilya Enkovich  <enkovich....@gmail.com>

        PR tree-optimization/68305
        * tree-vect-slp.c (vect_get_constant_vectors): Support
        COND_EXPR with SSA_NAME as a condition.

gcc/testsuite/

2015-11-12  Ilya Enkovich  <enkovich....@gmail.com>

        PR tree-optimization/68305
        * gcc.dg/vect/pr68305.c: New test.


diff --git a/gcc/testsuite/gcc.dg/vect/pr68305.c 
b/gcc/testsuite/gcc.dg/vect/pr68305.c
new file mode 100644
index 0000000..fde3db7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr68305.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-O3" } */
+/* { dg-additional-options "-mavx2" { target avx_runtime } } */
+
+int a, b;
+
+void
+fn1 ()
+{
+  int c, d;
+  for (; b; b++)
+    a = a ^ !c ^ !d;
+}
diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c
index 9d97140..9402474 100644
--- a/gcc/tree-vect-slp.c
+++ b/gcc/tree-vect-slp.c
@@ -2738,18 +2738,20 @@ vect_get_constant_vectors (tree op, slp_tree slp_node,
              switch (code)
                {
                  case COND_EXPR:
-                   if (op_num == 0 || op_num == 1)
-                     {
-                       tree cond = gimple_assign_rhs1 (stmt);
+                   {
+                     tree cond = gimple_assign_rhs1 (stmt);
+                     if (TREE_CODE (cond) == SSA_NAME)
+                       op = gimple_op (stmt, op_num + 1);
+                     else if (op_num == 0 || op_num == 1)
                        op = TREE_OPERAND (cond, op_num);
-                     }
-                   else
-                     {
-                       if (op_num == 2)
-                         op = gimple_assign_rhs2 (stmt);
-                       else
-                         op = gimple_assign_rhs3 (stmt);
-                     }
+                     else
+                       {
+                         if (op_num == 2)
+                           op = gimple_assign_rhs2 (stmt);
+                         else
+                           op = gimple_assign_rhs3 (stmt);
+                       }
+                   }
                    break;
 
                  case CALL_EXPR: