[PATCH] Fix PR60836

[Richard Biener]

This fixes PR60836 by emitting a non-proper PHI argument to the
incoming edge.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.

Richard.

2014-04-16  Richard Biener  <rguent...@suse.de>

        PR tree-optimization/60836
        * tree-vect-loop.c (vect_create_epilog_for_reduction): Force
        initial PHI args to be gimple values.

        * g++.dg/vect/pr60836.cc: New testcase.

Index: gcc/tree-vect-loop.c
===================================================================
*** gcc/tree-vect-loop.c        (revision 209423)
--- gcc/tree-vect-loop.c        (working copy)
*************** vect_create_epilog_for_reduction (vec<tr
*** 3951,3958 ****
    /* Set phi nodes arguments.  */
    FOR_EACH_VEC_ELT (reduction_phis, i, phi)
      {
!       tree vec_init_def = vec_initial_defs[i];
!       tree def = vect_defs[i];
        for (j = 0; j < ncopies; j++)
          {
            /* Set the loop-entry arg of the reduction-phi.  */
--- 3952,3963 ----
    /* Set phi nodes arguments.  */
    FOR_EACH_VEC_ELT (reduction_phis, i, phi)
      {
!       tree vec_init_def, def;
!       gimple_seq stmts;
!       vec_init_def = force_gimple_operand (vec_initial_defs[i], &stmts,
!                                          true, NULL_TREE);
!       gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts);
!       def = vect_defs[i];
        for (j = 0; j < ncopies; j++)
          {
            /* Set the loop-entry arg of the reduction-phi.  */
Index: gcc/testsuite/g++.dg/vect/pr60836.cc
===================================================================
*** gcc/testsuite/g++.dg/vect/pr60836.cc        (revision 0)
--- gcc/testsuite/g++.dg/vect/pr60836.cc        (working copy)
***************
*** 0 ****
--- 1,39 ----
+ // { dg-do compile }
+ 
+ int a, b;
+ typedef double (*NormFunc) (const int &);
+ int &
+ max (int &p1, int &p2)
+ {
+   if (p1 < p2)
+     return p2;
+   return p1;
+ }
+ 
+ struct A
+ {
+   int operator      () (int p1, int p2)
+     {
+       return max (p1, p2);
+     }
+ };
+ template < class, class > double
+ norm_ (const int &)
+ {
+   char c, d;
+   A e;
+   for (; a; a++)
+     {
+       b = e (b, d);
+       b = e (b, c);
+     }
+ }
+ 
+ void
+ norm ()
+ {
+   static NormFunc f = norm_ < int, A >;
+   f = 0;
+ }
+ 
+ // { dg-final { cleanup-tree-dump "vect" } }