[Bug middle-end/35611] [4.3/4.4 Regression] FAIL: libgomp.c/omp-nested-1.c execution test

["jakub at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from jakub at gcc dot gnu dot org  2008-03-18 11:14 -------
Seems OMP_ATOMIC_LOAD isn't properly regimplified and so &i in TREE_OPERAND
(omp_atomic_load, 1) isn't replaced with .omp_data_i->i.  For targets with
sync builtins this doesn't matter, as expand_omp_atomic for them runs all
addr references through force_gimple_operand_bsi and thus it is gimplified at
expand_omp time.  But the expand_omp_atomic_mutex fallback just assumes the
address is gimple value.

Here is a fix I'll be testing (though for hppa-linux I can only eyeball the
assembly).

2008-03-18  Jakub Jelinek  <jakub@redhat.com>

        PR middle-end/35611
        * gimplify.c (gimplify_expr): Gimplify second operand of
        OMP_ATOMIC_LOAD.

--- gcc/gimplify.c.jj   2008-03-06 18:45:59.000000000 +0100
+++ gcc/gimplify.c      2008-03-18 11:55:04.000000000 +0100
@@ -6022,12 +6022,18 @@ gimplify_expr (tree *expr_p, tree *pre_p

        case OMP_RETURN:
        case OMP_CONTINUE:
-        case OMP_ATOMIC_LOAD:
-        case OMP_ATOMIC_STORE:
-
+       case OMP_ATOMIC_STORE:
          ret = GS_ALL_DONE;
          break;

+       case OMP_ATOMIC_LOAD:
+         if (gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, NULL,
+             is_gimple_val, fb_rvalue) != GS_ALL_DONE)
+           ret = GS_ERROR;
+         else
+           ret = GS_ALL_DONE;
+         break;
+
        case POINTER_PLUS_EXPR:
           /* Convert ((type *)A)+offset into &A->field_of_type_and_offset.
             The second is gimple immediate saving a need for extra statement.

libgomp.c/pr26943-4.c used to fail intermitently before
http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=132977
but I certainly can't reproduce it with current trunk or 4.3, and I don't see
how this could be related to this - even -m32 -march=i386 has the needed sync
builtins - both QImode and SImode lock; add{b,l}.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
          Component|libgomp                     |middle-end
   Last reconfirmed|2008-03-18 00:09:30         |2008-03-18 11:14:25
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35611