[PATCH] Fix altivec-cell-2.C test regression (PR c++/83778)

[Jakub Jelinek]

Hi!

After the addition of location wrappers the
targetm.resolve_overloaded_builtin target hook is called with parameters
that may have those location wrappers in it.  Seems generic code has been
changed to fold_for_warn fold it away when looking for something that should
be e.g. INTEGER_CST.  Fixed thusly, bootstrapped/regtested on
powerpc64le-linux, ok for trunk?

2018-01-12  Jakub Jelinek  <ja...@redhat.com>

        PR c++/83778
        * config/rs6000/rs6000-c.c (altivec_resolve_overloaded_builtin): Call
        fold_for_warn before checking if arg2 is INTEGER_CST.

--- gcc/config/rs6000/rs6000-c.c.jj     2018-01-12 11:36:02.016223839 +0100
+++ gcc/config/rs6000/rs6000-c.c        2018-01-12 17:45:13.294256181 +0100
@@ -6496,6 +6496,8 @@ altivec_resolve_overloaded_builtin (loca
          tree call = NULL_TREE;
          int nunits = GET_MODE_NUNITS (mode);
 
+         arg2 = fold_for_warn (arg2);
+
          /* If the second argument is an integer constant, if the value is in
             the expected range, generate the built-in code if we can.  We need
             64-bit and direct move to extract the small integer vectors.  */
@@ -6640,7 +6642,7 @@ altivec_resolve_overloaded_builtin (loca
       arg0 = (*arglist)[0];
       arg1 = (*arglist)[1];
       arg1_type = TREE_TYPE (arg1);
-      arg2 = (*arglist)[2];
+      arg2 = fold_for_warn ((*arglist)[2]);
 
       if (TREE_CODE (arg1_type) != VECTOR_TYPE)
        goto bad;

        Jakub