On Fri, 4 Jan 2013, Jakub Jelinek wrote:
> Hi!
>
> As discussed in the PR, as all INTEGRAL_TYPE_P types with the same
> sign/precision are usually considered compatible
> (useless_type_conversion_p), during gimplify_one_sizepos the gimplifier
> can change e.g. an integer expression into e.g. VAR_DECL with ENUMERAL_TYPE,
> and when the gimplifier later on passes that to size_binop etc., it can
> trigger asserts because ENUMERAL_TYPE isn't considered sizetype-ish enough.
>
> The following patch (which I don't like too much admittedly) makes sure
> for constants we fold it back to INTEGER_TYPE constant, and for VAR_DECLs
> add an extra VAR_DECL in such a case.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
> Or do you prefer some other way?
The other way would be
Index: gcc/fold-const.c
===================================================================
--- gcc/fold-const.c (revision 194900)
+++ gcc/fold-const.c (working copy)
@@ -900,9 +900,9 @@ associate_trees (location_t loc, tree t1
static bool
int_binop_types_match_p (enum tree_code code, const_tree type1,
const_tree type2)
{
- if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
+ if (!INTEGRAL_TYPE_P (type1) && !POINTER_TYPE_P (type1))
return false;
- if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
+ if (!INTEGRAL_TYPE_P (type2) && !POINTER_TYPE_P (type2))
return false;
switch (code)
at least the present check doesn't really verify we use sizetypes
for size_*op anymore. I'd agree more with your patch if we'd
verify that we have proper [s]sizetype, [s]bitsizetype type
arguments to size_*op functions (which of course would be again
questionable to some degree).
That said - we seem to have moved into a direction that makes
the above patch not so questionable.
Richard.
> 2013-01-04 Jakub Jelinek <[email protected]>
>
> PR middle-end/55851
> * gimplify.c (gimplify_one_sizepos): Ensure gimplify_expr
> doesn't turn *expr_p from INTEGER_TYPE expression into e.g.
> ENUMERAL_TYPE expression.
>
> * gcc.c-torture/compile/pr55851.c: New test.
>
> --- gcc/gimplify.c.jj 2012-12-20 19:13:00.000000000 +0100
> +++ gcc/gimplify.c 2013-01-03 16:16:07.288707387 +0100
> @@ -8180,6 +8180,26 @@ gimplify_one_sizepos (tree *expr_p, gimp
> *expr_p = unshare_expr (expr);
>
> gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue);
> +
> + /* Ensure we don't change an INTEGER_TYPE expression into e.g.
> ENUMERAL_TYPE
> + expression. */
> + if (TREE_CODE (TREE_TYPE (*expr_p)) != TREE_CODE (TREE_TYPE (expr)))
> + {
> + gcc_checking_assert (useless_type_conversion_p (TREE_TYPE (expr),
> + TREE_TYPE (*expr_p)));
> + if (TREE_CODE (*expr_p) == INTEGER_CST)
> + *expr_p = fold_convert (TREE_TYPE (expr), *expr_p);
> + else
> + {
> + tree var = create_tmp_var (TREE_TYPE (expr), NULL);
> + tree mod = build2 (INIT_EXPR, TREE_TYPE (var),
> + var, unshare_expr (*expr_p));
> + SET_EXPR_LOCATION (mod, EXPR_LOC_OR_HERE (*expr_p));
> + gimplify_and_add (mod, stmt_p);
> + ggc_free (mod);
> + *expr_p = var;
> + }
> + }
> }
>
> /* Gimplify the body of statements of FNDECL and return a GIMPLE_BIND node
> --- gcc/testsuite/gcc.c-torture/compile/pr55851.c.jj 2013-01-03
> 16:20:19.085284806 +0100
> +++ gcc/testsuite/gcc.c-torture/compile/pr55851.c 2013-01-03
> 16:19:27.698571718 +0100
> @@ -0,0 +1,12 @@
> +/* PR middle-end/55851 */
> +
> +enum { A = 1UL, B = -1UL } var = A;
> +void foo (char *);
> +
> +void
> +test (void)
> +{
> + char vla[1][var];
> + vla[0][0] = 1;
> + foo (&vla[0][0]);
> +}
>
> Jakub
>
>
--
Richard Biener <[email protected]>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imend
