On 10.04.2018 13:40, Alexander Monakov wrote:
> this fixes a simple "regression" under the qsort_chk umbrella: sched-deps
> analysis has deps->readonly flag, but macro-fusion code does not respect it
> and mutates instructions. This breaks an assumption in sel_rank_for_schedule
> and manifests as qsort checking error.
> Since sched_macro_fuse_insns is only called to set SCHED_GROUP_P on suitable
> insns, guard the call with !deps->readonly.
> Bootstrapped/regtested on x86_64 with sel-sched active and
> --with-cpu=sandybridge to exercise macro-fusion code and verified on aarch64
> cross-compiler that the failing testcase given in the PR is fixed.
> OK to apply?
Fine with me but you need a scheduler maintainer approval.
> PR rtl-optimization/84566
> * sched-deps.c (sched_analyze_insn): Check deps->readonly when invoking
> diff --git a/gcc/sched-deps.c b/gcc/sched-deps.c
> index 9a5cbebea40..120b5f0ddc1 100644
> --- a/gcc/sched-deps.c
> +++ b/gcc/sched-deps.c
> @@ -2897,7 +2897,8 @@ sched_analyze_insn (struct deps_desc *deps, rtx x,
> rtx_insn *insn)
> && code == SET);
> /* Group compare and branch insns for macro-fusion. */
> - if (targetm.sched.macro_fusion_p
> + if (!deps->readonly
> + && targetm.sched.macro_fusion_p
> && targetm.sched.macro_fusion_p ())
> sched_macro_fuse_insns (insn);