On Thu, 22 Dec 2022, Jakub Jelinek wrote:
> Hi!
>
> The following testcase ICEs on aarch64, because insert_const_anchor
> inserts invalid CONST_INT into the CSE tables - 0x80000000 for SImode.
> The second hunk of the patch fixes that, the first one is to avoid
> triggering undefined behavior at compile time during compute_const_anchors
> computations - performing those additions and subtractions in
> HOST_WIDE_INT means it can overflow for certain constants.
>
> Bootstrapped/regtested on aarch64-linux (which does have nonzero
> target.const_anchor) and x86_64-linux and i686-linux (which have it
> zero). Ok for trunk?
>
> 2022-12-22 Jakub Jelinek <ja...@redhat.com>
>
> PR rtl-optimization/108193
> * cse.cc (compute_const_anchors): Change n type to
> unsigned HOST_WIDE_INT, adjust comparison against it to avoid
> warnings. Formatting fix.
> (insert_const_anchor): Use gen_int_mode instead of GEN_INT.
>
> * gfortran.dg/pr108193.f90: New test.
>
> --- gcc/cse.cc.jj 2022-06-28 13:03:30.699692752 +0200
> +++ gcc/cse.cc 2022-12-21 12:58:24.277945065 +0100
> @@ -1169,14 +1169,14 @@ compute_const_anchors (rtx cst,
> HOST_WIDE_INT *lower_base, HOST_WIDE_INT *lower_offs,
> HOST_WIDE_INT *upper_base, HOST_WIDE_INT *upper_offs)
> {
> - HOST_WIDE_INT n = INTVAL (cst);
> + unsigned HOST_WIDE_INT n = INTVAL (cst);
UINTVAL?
Otherwise OK.
Thanks,
Richard.
>
> *lower_base = n & ~(targetm.const_anchor - 1);
> - if (*lower_base == n)
> + if ((unsigned HOST_WIDE_INT) *lower_base == n)
> return false;
>
> - *upper_base =
> - (n + (targetm.const_anchor - 1)) & ~(targetm.const_anchor - 1);
> + *upper_base = ((n + (targetm.const_anchor - 1))
> + & ~(targetm.const_anchor - 1));
> *upper_offs = n - *upper_base;
> *lower_offs = n - *lower_base;
> return true;
> @@ -1193,7 +1193,7 @@ insert_const_anchor (HOST_WIDE_INT ancho
> rtx anchor_exp;
> rtx exp;
>
> - anchor_exp = GEN_INT (anchor);
> + anchor_exp = gen_int_mode (anchor, mode);
> hash = HASH (anchor_exp, mode);
> elt = lookup (anchor_exp, hash, mode);
> if (!elt)
> --- gcc/testsuite/gfortran.dg/pr108193.f90.jj 2022-12-21 13:02:21.925513332
> +0100
> +++ gcc/testsuite/gfortran.dg/pr108193.f90 2022-12-21 13:01:38.595139040
> +0100
> @@ -0,0 +1,24 @@
> +! PR rtl-optimization/108193
> +! { dg-do compile { target pthread } }
> +! { dg-options "-O2 -fsplit-loops -ftree-parallelize-loops=2
> -fno-tree-dominator-opts" }
> +
> +subroutine foo (n, r)
> + implicit none
> + integer :: i, j, n
> + real :: s, r(*)
> +
> + s = 0.0
> +
> + do j = 1, 2
> + do i = j, n
> + s = r(i)
> + end do
> + end do
> +
> + do i = 1, n
> + do j = i, n
> + s = s + 1
> + end do
> + r(i) = s
> + end do
> +end subroutine foo
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
HRB 36809 (AG Nuernberg)
