This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: Problems with a patch to improve dependence analysis
- From: Zdenek Dvorak <rakdver at kam dot mff dot cuni dot cz>
- To: "Sjodin, Jan" <Jan dot Sjodin at amd dot com>
- Cc: GCC Patches <gcc-patches at gcc dot gnu dot org>
- Date: Sun, 15 Jul 2007 22:12:24 +0200
- Subject: Re: Problems with a patch to improve dependence analysis
- References: <7986CEFCE5C2954A88BEE2CAB6FAB374026FF604@SAUSEXMB2.amd.com>
Hello,
> This worked for the most part (non-bootstrap, make check), but there are
> errors during bootstrap:
>
> -----------------------------------------------------------------------
> _r4.c: In function 'matmul_r4':
> /home/jsjodin/Work/Project/GCC/Latest/trunk/libgfortran/generated/matm
> ul
> _r4.c:87: error: expected an SSA_NAME object
> /home/jsjodin/Work/Project/GCC/Latest/trunk/libgfortran/generated/matm
> ul
> _r4.c:87: error: in statement
> # VUSE <SMT.37> { SMT.37 }
> D.5431_402 = retarray_45(D)->data;
> ----------------------------------------------------------------------
the problem is that you have virtual operands outside of ssa form
(SMT.37) here. You do not give enough information to tell why this
happens; my guess is that
> Index: trunk/gcc/tree-data-ref.c
> ===================================================================
> --- trunk/gcc/tree-data-ref.c (revision 126419)
> +++ trunk/gcc/tree-data-ref.c (working copy)
> @@ -566,6 +566,25 @@ split_constant_offset (tree exp, tree *v
> return;
> }
>
> + case SSA_NAME:
> + {
> + tree def_stmt = SSA_NAME_DEF_STMT (exp);
> + if (TREE_CODE (def_stmt) == GIMPLE_MODIFY_STMT)
> + {
> + tree def_stmt_rhs = GIMPLE_STMT_OPERAND (def_stmt, 1);
> + if (!TREE_SIDE_EFFECTS (def_stmt_rhs)
> + && EXPR_P (def_stmt_rhs))
this condition is not restrictive enough; try using
(EXPR_P (def_stmt_rhs) && !REFERENCE_CLASS_P (def_stmt_rhs))
Zdenek