On Wed, May 27, 2026 at 5:51 AM Daniel Barboza
<[email protected]> wrote:
>
> Remove the warn_strict_overflow block along with two Wstrict_overflow
> supressed warnings.
Ok.
>
> gcc/ChangeLog:
>
> * tree-ssa-loop-ch.cc (ch_base::copy_headers): Removed
> warn_strict_overflow logic.
> ---
> gcc/tree-ssa-loop-ch.cc | 44 -----------------------------------------
> 1 file changed, 44 deletions(-)
>
> diff --git a/gcc/tree-ssa-loop-ch.cc b/gcc/tree-ssa-loop-ch.cc
> index 5fdb9a009c9..10e72470643 100644
> --- a/gcc/tree-ssa-loop-ch.cc
> +++ b/gcc/tree-ssa-loop-ch.cc
> @@ -1019,50 +1019,6 @@ ch_base::copy_headers (function *fun)
> delete candidate.invariant_exits;
> copied.safe_push (std::make_pair (entry, loop));
>
> - /* If the loop has the form "for (i = j; i < j + 10; i++)" then
> - this copying can introduce a case where we rely on undefined
> - signed overflow to eliminate the preheader condition, because
> - we assume that "j < j + 10" is true. We don't want to warn
> - about that case for -Wstrict-overflow, because in general we
> - don't warn about overflow involving loops. Prevent the
> - warning by setting the no_warning flag in the condition. */
> - if (warn_strict_overflow > 0)
> - {
> - unsigned int i;
> -
> - for (i = 0; i < n_bbs; ++i)
> - {
> - gimple_stmt_iterator bsi;
> -
> - for (bsi = gsi_start_bb (copied_bbs[i]);
> - !gsi_end_p (bsi);
> - gsi_next (&bsi))
> - {
> - gimple *stmt = gsi_stmt (bsi);
> - if (gimple_code (stmt) == GIMPLE_COND)
> - {
> - tree lhs = gimple_cond_lhs (stmt);
> - if (gimple_cond_code (stmt) != EQ_EXPR
> - && gimple_cond_code (stmt) != NE_EXPR
> - && INTEGRAL_TYPE_P (TREE_TYPE (lhs))
> - && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (lhs)))
> - suppress_warning (stmt, OPT_Wstrict_overflow_);
> - }
> - else if (is_gimple_assign (stmt))
> - {
> - enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
> - tree rhs1 = gimple_assign_rhs1 (stmt);
> - if (TREE_CODE_CLASS (rhs_code) == tcc_comparison
> - && rhs_code != EQ_EXPR
> - && rhs_code != NE_EXPR
> - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))
> - && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (rhs1)))
> - suppress_warning (stmt, OPT_Wstrict_overflow_);
> - }
> - }
> - }
> - }
> -
> /* Update header of the loop. */
> loop->header = header;
> /* Find correct latch. We only duplicate chain of conditionals so
> --
> 2.43.0
>
