On Wed, 5 Jan 2022, Jakub Jelinek wrote:
> Hi!
>
> For ADDR_EXPR gimple_debug_bind_get_value fold_stmt_1 uses
> maybe_canonicalize_mem_ref_addr earlier and I think that should
> resolve the concerns raised in PR52329. But folding ADDR_EXPR
> operand using maybe_fold_reference and then taking address of that
> looks like an invalid transformation, it can transform
> # DEBUG D.4293 => &a[0]
> into
> # DEBUG D.4293 => &2.0e+0
> etc., all we want to allow are the lhs folding of the operand which
> maybe_fold_reference no longer does since r12-21-g0bf8cd9d5e8ac.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Thanks,
Richard.
> 2022-01-05 Jakub Jelinek <ja...@redhat.com>
>
> PR fortran/103691
> * gimple-fold.c (fold_stmt_1): Don't call maybe_fold_reference
> for DEBUG stmts with ADDR_EXPR gimple_debug_bind_get_value,
> it can do unwanted rhs folding like &a[0] into &2.0 etc.
>
> * gfortran.dg/pr103691.f90: New test.
>
> --- gcc/gimple-fold.c.jj 2022-01-03 10:40:42.872140874 +0100
> +++ gcc/gimple-fold.c 2022-01-04 13:29:17.571321684 +0100
> @@ -6283,8 +6283,7 @@ fold_stmt_1 (gimple_stmt_iterator *gsi,
> if (gimple_debug_bind_p (stmt))
> {
> tree val = gimple_debug_bind_get_value (stmt);
> - if (val
> - && REFERENCE_CLASS_P (val))
> + if (val && REFERENCE_CLASS_P (val))
> {
> tree tem = maybe_fold_reference (val);
> if (tem)
> @@ -6292,18 +6291,6 @@ fold_stmt_1 (gimple_stmt_iterator *gsi,
> gimple_debug_bind_set_value (stmt, tem);
> changed = true;
> }
> - }
> - else if (val
> - && TREE_CODE (val) == ADDR_EXPR)
> - {
> - tree ref = TREE_OPERAND (val, 0);
> - tree tem = maybe_fold_reference (ref);
> - if (tem)
> - {
> - tem = build_fold_addr_expr_with_type (tem, TREE_TYPE (val));
> - gimple_debug_bind_set_value (stmt, tem);
> - changed = true;
> - }
> }
> }
> break;
> --- gcc/testsuite/gfortran.dg/pr103691.f90.jj 2022-01-04 13:31:23.564557726
> +0100
> +++ gcc/testsuite/gfortran.dg/pr103691.f90 2022-01-04 13:31:08.053774883
> +0100
> @@ -0,0 +1,9 @@
> +! PR fortran/103691
> +! { dg-do compile }
> +! { dg-options "-O2 -g" }
> +
> +program pr103691
> + real, parameter :: a(0) = 2.0
> + real, allocatable :: b(:)
> + allocate (b, mold=a)
> +end
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Ivo Totev; HRB 36809 (AG Nuernberg)
