From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2063) id BC9B13858C52; Tue, 14 Jun 2022 05:58:23 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org BC9B13858C52 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Kewen Lin To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-1083] vect: Move suggested_unroll_factor applying [PR105940] X-Act-Checkin: gcc X-Git-Author: Kewen Lin X-Git-Refname: refs/heads/master X-Git-Oldrev: 077438933cf94f00cc5edf974338c11ba4bf7a39 X-Git-Newrev: f907cf4c07cf51863dadbe90894e2ae3382bada5 Message-Id: <20220614055823.BC9B13858C52@sourceware.org> Date: Tue, 14 Jun 2022 05:58:23 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Jun 2022 05:58:23 -0000 https://gcc.gnu.org/g:f907cf4c07cf51863dadbe90894e2ae3382bada5 commit r13-1083-gf907cf4c07cf51863dadbe90894e2ae3382bada5 Author: Kewen Lin Date: Tue Jun 14 00:57:01 2022 -0500 vect: Move suggested_unroll_factor applying [PR105940] As PR105940 shown, when rs6000 port tries to assign m_suggested_unroll_factor by 4 or so, there will be ICE on: exact_div (LOOP_VINFO_VECT_FACTOR (loop_vinfo), loop_vinfo->suggested_unroll_factor); In function vect_analyze_loop_2, the current place of suggested_unroll_factor applying can't guarantee it's applied for all cases. As the case shows, vectorizer could retry with SLP forced off, the vf is reset by saved_vectorization_factor which isn't applied with suggested_unroll_factor before. It means it can end up with one vf which neglects suggested_unroll_factor. I think it's off design, we should move the applying of suggested_unroll_factor after start_over. PR tree-optimization/105940 gcc/ChangeLog: * tree-vect-loop.cc (vect_analyze_loop_2): Move the place of applying suggested_unroll_factor after start_over. Diff: --- gcc/tree-vect-loop.cc | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index 246347b9b08..e05f8e87f7d 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -2388,15 +2388,15 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo, bool &fatal, set of rgroups. */ gcc_assert (LOOP_VINFO_MASKS (loop_vinfo).is_empty ()); + /* This is the point where we can re-start analysis with SLP forced off. */ +start_over: + /* Apply the suggested unrolling factor, this was determined by the backend during finish_cost the first time we ran the analyzis for this vector mode. */ if (loop_vinfo->suggested_unroll_factor > 1) LOOP_VINFO_VECT_FACTOR (loop_vinfo) *= loop_vinfo->suggested_unroll_factor; - /* This is the point where we can re-start analysis with SLP forced off. */ -start_over: - /* Now the vectorization factor is final. */ poly_uint64 vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo); gcc_assert (known_ne (vectorization_factor, 0U));