On Tue, Jul 16, 2024 at 3:36 PM Andrew Pinski <quic_apin...@quicinc.com> wrote:
>
> Like r15-1610-gb6215065a5b143 (which adds one for late_combine),
> adding one for ext_dce is useful to debug some issues with this pass.
>
> Bootstrapped and tested on x86_64-linux-gnu with no regressions.
>
> gcc/ChangeLog:
>
> * dbgcnt.def (ext_dce): New debug counter.
> * ext-dce.cc (ext_dce_try_optimize_insn): Reject the insn
> if the debug counter says so.
I forgot to update the changelog after I added the name change of
ext_dce inside ex-dce.cc. I don't think I need to send a new patch for
this since it is only a change to the commit message.
This will be added to the changelog (note there is a tab before the
`(`; gmail removed it):
(ext_dce): Rename to ...
(ext_dce_execute): This.
(pass_ext_dce::execute): Update for the name of ext_dce.
Thanks,
Andrew
>
> Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
> ---
> gcc/dbgcnt.def | 1 +
> gcc/ext-dce.cc | 16 +++++++++++++---
> 2 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/gcc/dbgcnt.def b/gcc/dbgcnt.def
> index e0b9b1b2a76..ac1f8709849 100644
> --- a/gcc/dbgcnt.def
> +++ b/gcc/dbgcnt.def
> @@ -162,6 +162,7 @@ DEBUG_COUNTER (dom_unreachable_edges)
> DEBUG_COUNTER (dse)
> DEBUG_COUNTER (dse1)
> DEBUG_COUNTER (dse2)
> +DEBUG_COUNTER (ext_dce)
> DEBUG_COUNTER (form_fma)
> DEBUG_COUNTER (gcse2_delete)
> DEBUG_COUNTER (gimple_unroll)
> diff --git a/gcc/ext-dce.cc b/gcc/ext-dce.cc
> index 6c961feee63..6d4b8858ec6 100644
> --- a/gcc/ext-dce.cc
> +++ b/gcc/ext-dce.cc
> @@ -33,6 +33,7 @@ along with GCC; see the file COPYING3. If not see
> #include "rtl-iter.h"
> #include "df.h"
> #include "print-rtl.h"
> +#include "dbgcnt.h"
>
> /* These should probably move into a C++ class. */
> static vec<bitmap_head> livein;
> @@ -312,6 +313,15 @@ ext_dce_try_optimize_insn (rtx_insn *insn, rtx set)
> print_rtl_single (dump_file, SET_SRC (set));
> }
>
> + /* We decided to turn do the optimization but allow it to be rejected for
> + bisection purposes. */
> + if (!dbg_cnt (::ext_dce))
> + {
> + if (dump_file)
> + fprintf (dump_file, "Rejected due to debug counter.\n");
> + return;
> + }
> +
> new_pattern = simplify_gen_subreg (GET_MODE (src), inner,
> GET_MODE (inner), 0);
> /* simplify_gen_subreg may fail in which case NEW_PATTERN will be NULL.
> @@ -881,8 +891,8 @@ static bool ext_dce_rd_confluence_n (edge) { return true;
> }
> are never read. Turn such extensions into SUBREGs instead which
> can often be propagated away. */
>
> -static void
> -ext_dce (void)
> +void
> +ext_dce_execute (void)
> {
> df_analyze ();
> ext_dce_init ();
> @@ -929,7 +939,7 @@ public:
> virtual bool gate (function *) { return flag_ext_dce && optimize > 0; }
> virtual unsigned int execute (function *)
> {
> - ext_dce ();
> + ext_dce_execute ();
> return 0;
> }
>
> --
> 2.43.0
>
