On Fri, Sep 11, 2026 at 5:13 AM xiezhiheng <[email protected]> wrote:
>
> As mentioned in
> https://gcc.gnu.org/pipermail/gcc-patches/2026-September/730781.html,
> issue_rate values on modern cores keep increasing, and the maximum
> issue_rate in the AArch64 backend has reached 10, causing an overflow
> in the calculation of max_lookahead_tries. Change its type to int64_t.
>
> Bootstrapped and tested on aarch64-linux-gnu and x86_64-linux-gnu, no
> regression.
OK.
> gcc/ChangeLog:
>
> * haifa-sched.cc (max_issue): Change max_lookahead_tries type to
> int64_t
> ---
> gcc/haifa-sched.cc | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/haifa-sched.cc b/gcc/haifa-sched.cc
> index 879749e9785..733a83034bf 100644
> --- a/gcc/haifa-sched.cc
> +++ b/gcc/haifa-sched.cc
> @@ -5921,7 +5921,7 @@ int dfa_lookahead;
> might be incomplete and such insn might occur. For such
> descriptions, the complexity of algorithm (without the constraint)
> could achieve DFA_LOOKAHEAD ** N , where N is the queue length. */
> -static int max_lookahead_tries;
> +static int64_t max_lookahead_tries;
>
> /* The following function returns maximal (or close to maximal) number
> of insns which can be issued on the same cycle and one of which
> @@ -5941,8 +5941,9 @@ int
> max_issue (struct ready_list *ready, int privileged_n, state_t state,
> bool first_cycle_insn_p, int *index)
> {
> - int n, i, all, n_ready, best, delay, tries_num;
> + int n, i, all, n_ready, best, delay;
> int more_issue;
> + int64_t tries_num;
> struct choice_entry *top;
> rtx_insn *insn;
>
> --
> 2.43.0
>
