On Sat, 6 Jan 2024, Jakub Jelinek wrote:
> Hi!
>
> The following testcase ICEs during regimplificatgion since the addition of
> (convert (eqne zero_one_valued_p@0 INTEGER_CST@1))
> simplification. That simplification is novel in the sense that in
> gimplify_expr it can turn an expression (comparison in particular) into
> a SSA_NAME. Normally when gimplify_expr sees originally a SSA_NAME, it does
> case SSA_NAME:
> /* Allow callbacks into the gimplifier during optimization. */
> ret = GS_ALL_DONE;
> break;
> and doesn't try to recalculate side effects because of that, but in this
> case gimplify_expr normally enters the:
> default:
> switch (TREE_CODE_CLASS (TREE_CODE (*expr_p)))
> {
> case tcc_comparison:
> then does
> *expr_p = gimple_boolify (*expr_p);
> and then
> *expr_p = fold_convert_loc (input_location,
> org_type, *expr_p);
> with this new match.pd simplification turns that tcc_comparison class
> into SSA_NAME. Unlike the outer SSA_NAME handling though, this falls
> through into
> recalculate_side_effects (*expr_p);
>
> dont_recalculate:
> break;
> but unfortunately recalculate_side_effects doesn't handle SSA_NAME and ICEs
> on it.
> SSA_NAMEs don't ever have TREE_SIDE_EFFECTS set on those, so the following
> patch fixes it by handling it similarly to the tcc_constant case.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Richard.
> 2024-01-06 Jakub Jelinek
>
> PR tree-optimization/113228
> * gimplify.cc (recalculate_side_effects): Do nothing for SSA_NAMEs.
>
> * gcc.c-torture/compile/pr113228.c: New test.
>
> --- gcc/gimplify.cc.jj2024-01-03 11:51:40.744603324 +0100
> +++ gcc/gimplify.cc 2024-01-05 13:32:34.351336320 +0100
> @@ -3344,6 +3344,9 @@ recalculate_side_effects (tree t)
>return;
>
> default:
> + if (code == SSA_NAME)
> + /* No side-effects. */
> + return;
>gcc_unreachable ();
> }
> }
> --- gcc/testsuite/gcc.c-torture/compile/pr113228.c.jj 2024-01-05
> 13:27:42.876330301 +0100
> +++ gcc/testsuite/gcc.c-torture/compile/pr113228.c2024-01-05
> 13:27:22.503609458 +0100
> @@ -0,0 +1,17 @@
> +/* PR tree-optimization/113228 */
> +
> +int a, b, c, d, i;
> +
> +void
> +foo (void)
> +{
> + int k[3] = {};
> + int *l = &a;
> + for (d = 0; c; c--)
> +for (i = 0; i <= 9; i++)
> + {
> + for (b = 1; b <= 4; b++)
> + k[0] = k[0] == 0;
> + *l |= k[d];
> + }
> +}
>
> Jakub
>
>
--
Richard Biener
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
