[PATCH] Handle COND_EXPR/VEC_COND_EXPR in walk_stmt_load_store_addr_ops and ssa verification
Richard Guenther
rguenther@suse.de
Fri Oct 14 09:37:00 GMT 2011
On Thu, 13 Oct 2011, Jakub Jelinek wrote:
> Hi!
>
> Andrew mentioned on IRC he found walk_stmt_load_store_addr_ops
> doesn't handle COND_EXPR weirdo first argument well, the following
> patch is an attempt to handle that.
>
> I've noticed similar spot in verify_ssa, though in that case I'm not
> sure about whether the change is so desirable, as it doesn't seem to
> handle SSA_NAMEs embedded in MEM_EXPRs, ARRAY_REFs etc. either.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
> Or just the gimple.c part?
The verify-ssa code is somewhat odd, I'd have expected a
if (count != 0)
error ();
after that loop, but that of course would have triggered already ;)
The code tries to be more something like verify_operands () which
verifies that update_stmt () was called. Thus I'd say we
should rather (at the end of processing the stmt) do sth like
saved_need_update = need_ssa_update ();
need_ssa_update = false;
record-state-of-use-operands
update_stmt
compare state-of-use-operands
assert (!need_ssa_update ());
need_ssa_update = saved_need_update;
unfortunately update_stmt may change the operand list even
if no changes occur (IIRC).
But I'm not sure. I think we should delete this check from
verify_ssa and instead have a corresponding check in
verify_stmts (which already properly walks trees) that
for an SSA name we encounter we do have a properly linked use
(see verify_expr, maybe it's easy to do that for the SSA_NAME
case - at least it's easy without trying to avoid a
FOR_EACH_SSA_USE_OPERAND (, SSA_OP_USE) on the stmt for
each SSA_NAME we encounter).
The gimple.c part is ok.
Thanks,
Richard.
> 2011-10-13 Jakub Jelinek <jakub@redhat.com>
>
> * gimple.c (walk_stmt_load_store_addr_ops): Call visit_addr
> also on COND_EXPR/VEC_COND_EXPR comparison operands if they are
> ADDR_EXPRs.
>
> * tree-ssa.c (verify_ssa): For COND_EXPR/VEC_COND_EXPR count
> SSA_NAMEs in comparison operand as well.
>
> --- gcc/gimple.c.jj 2011-10-13 11:13:39.000000000 +0200
> +++ gcc/gimple.c 2011-10-13 11:15:25.000000000 +0200
> @@ -5313,9 +5313,24 @@ walk_stmt_load_store_addr_ops (gimple st
> || gimple_code (stmt) == GIMPLE_COND))
> {
> for (i = 0; i < gimple_num_ops (stmt); ++i)
> - if (gimple_op (stmt, i)
> - && TREE_CODE (gimple_op (stmt, i)) == ADDR_EXPR)
> - ret |= visit_addr (stmt, TREE_OPERAND (gimple_op (stmt, i), 0), data);
> + {
> + tree op = gimple_op (stmt, i);
> + if (op == NULL_TREE)
> + ;
> + else if (TREE_CODE (op) == ADDR_EXPR)
> + ret |= visit_addr (stmt, TREE_OPERAND (op, 0), data);
> + /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
> + tree with two operands. */
> + else if (i == 1 && COMPARISON_CLASS_P (op))
> + {
> + if (TREE_CODE (TREE_OPERAND (op, 0)) == ADDR_EXPR)
> + ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 0),
> + 0), data);
> + if (TREE_CODE (TREE_OPERAND (op, 1)) == ADDR_EXPR)
> + ret |= visit_addr (stmt, TREE_OPERAND (TREE_OPERAND (op, 1),
> + 0), data);
> + }
> + }
> }
> else if (is_gimple_call (stmt))
> {
> --- gcc/tree-ssa.c.jj 2011-10-07 10:03:28.000000000 +0200
> +++ gcc/tree-ssa.c 2011-10-13 11:19:30.000000000 +0200
> @@ -1069,14 +1069,27 @@ verify_ssa (bool check_modified_stmt)
> for (i = 0; i < gimple_num_ops (stmt); i++)
> {
> op = gimple_op (stmt, i);
> - if (op && TREE_CODE (op) == SSA_NAME && --count < 0)
> + if (op == NULL_TREE)
> + continue;
> + if (TREE_CODE (op) == SSA_NAME)
> + --count;
> + /* COND_EXPR and VCOND_EXPR rhs1 argument is a comparison
> + tree with two operands. */
> + else if (i == 1 && COMPARISON_CLASS_P (op))
> {
> - error ("number of operands and imm-links don%'t agree"
> - " in statement");
> - print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS);
> - goto err;
> + if (TREE_CODE (TREE_OPERAND (op, 0)) == SSA_NAME)
> + --count;
> + if (TREE_CODE (TREE_OPERAND (op, 1)) == SSA_NAME)
> + --count;
> }
> }
> + if (count < 0)
> + {
> + error ("number of operands and imm-links don%'t agree"
> + " in statement");
> + print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS);
> + goto err;
> + }
>
> FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE|SSA_OP_VUSE)
> {
>
> Jakub
>
>
--
Richard Guenther <rguenther@suse.de>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer
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