From patchwork Wed Jan 4 13:45:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "juzhe.zhong@rivai.ai" X-Patchwork-Id: 62702 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 47A41385841C for ; Wed, 4 Jan 2023 13:45:58 +0000 (GMT) X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from smtpbguseast2.qq.com (smtpbguseast2.qq.com [54.204.34.130]) by sourceware.org (Postfix) with ESMTPS id 7BD4B3858D35 for ; Wed, 4 Jan 2023 13:45:35 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 7BD4B3858D35 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=rivai.ai Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=rivai.ai X-QQ-mid: bizesmtp90t1672839929tfa7uq3y Received: from rios-cad5.localdomain ( [58.60.1.11]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 04 Jan 2023 21:45:28 +0800 (CST) X-QQ-SSF: 01400000002000E0L000B00A0000000 X-QQ-FEAT: q+EIYT+FhZqOjfmZsk57R2uI73RlngppfA9FtBa5EbkLbwy5YAZPEXMefZaiS GxukHn1/Z1/6/tsyT5oxnHOHnq9lJO/6pyOQv1Gb0n5hI59jWcUg39eQ0PmNvS7XueaxsQR 94ZSuNnAq64L1ViK4eBxsGHbjdeskk94mLf8dclgu00IZUX2uOYbeaHSnzw/WK2X24o3tTd dyvpQgy2WCn9WfAhS6BO/ZmJSOFvoVC0AiLZpHvnTqiZDMuXRZZJVUpznK84tf7CCfLqYjO s8BWoSsbf2Ru8gYTl8pgBg+TmxWJ+3mttqdVxN3hsR1IqXsg66TqkDXOmVYEIqcdaU30Sma 52IZBfy2of+RbJT0nLFbYgB9WPyB2KtSWavXwWJ+RKVnX3F0UhLWpx++tV8ow== X-QQ-GoodBg: 2 From: juzhe.zhong@rivai.ai To: gcc-patches@gcc.gnu.org Cc: kito.cheng@gmail.com, palmer@dabbelt.com, Ju-Zhe Zhong Subject: [PATCH] RISC-V: Refine Phase 3 of VSETVL PASS Date: Wed, 4 Jan 2023 21:45:26 +0800 Message-Id: <20230104134526.206115-1-juzhe.zhong@rivai.ai> X-Mailer: git-send-email 2.36.3 MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:rivai.ai:qybglogicsvr:qybglogicsvr7 X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" From: Ju-Zhe Zhong gcc/ChangeLog: * config/riscv/riscv-vsetvl.cc (can_backward_propagate_p): Fix for null iter_bb. (vector_insn_info::set_demand_info): New function. (pass_vsetvl::emit_local_forward_vsetvls): Adjust for refinement of Phase 3. (pass_vsetvl::merge_successors): Ditto. (pass_vsetvl::compute_global_backward_infos): Ditto. (pass_vsetvl::backward_demand_fusion): Ditto. (pass_vsetvl::forward_demand_fusion): Ditto. (pass_vsetvl::demand_fusion): New function. (pass_vsetvl::lazy_vsetvl): Adjust for refinement of phase 3. * config/riscv/riscv-vsetvl.h: New function declaration. --- gcc/config/riscv/riscv-vsetvl.cc | 138 ++++++++++++++++++++++++++++--- gcc/config/riscv/riscv-vsetvl.h | 1 + 2 files changed, 128 insertions(+), 11 deletions(-) diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc index 52f0195980a..d42cfa91d63 100644 --- a/gcc/config/riscv/riscv-vsetvl.cc +++ b/gcc/config/riscv/riscv-vsetvl.cc @@ -43,7 +43,7 @@ along with GCC; see the file COPYING3. If not see - Phase 2 - Emit vsetvl instructions within each basic block according to demand, compute and save ANTLOC && AVLOC of each block. - - Phase 3 - Backward demanded info propagation and fusion across blocks. + - Phase 3 - Backward && forward demanded info propagation and fusion across blocks. - Phase 4 - Lazy code motion including: compute local properties, pre_edge_lcm and vsetvl insertion && delete edges for LCM results. @@ -434,8 +434,12 @@ can_backward_propagate_p (const function_info *ssa, const basic_block cfg_bb, set_info *ultimate_def = look_through_degenerate_phi (set); const basic_block ultimate_bb = ultimate_def->bb ()->cfg_bb (); FOR_BB_BETWEEN (iter_bb, ultimate_bb, def->bb ()->cfg_bb (), next_bb) - if (iter_bb->index == cfg_bb->index) - return true; + { + if (!iter_bb) + break; + if (iter_bb->index == cfg_bb->index) + return true; + } return false; }; @@ -1172,6 +1176,19 @@ vector_insn_info::parse_insn (insn_info *insn) m_demands[DEMAND_MASK_POLICY] = true; } +void +vector_insn_info::set_demand_info (const vector_insn_info &other) +{ + set_sew (other.get_sew ()); + set_vlmul (other.get_vlmul ()); + set_ratio (other.get_ratio ()); + set_ta (other.get_ta ()); + set_ma (other.get_ma ()); + set_avl_info (other.get_avl_info ()); + for (size_t i = 0; i < NUM_DEMAND; i++) + m_demands[i] = other.demand_p ((enum demand_type) i); +} + void vector_insn_info::demand_vl_vtype () { @@ -1691,8 +1708,10 @@ private: void emit_local_forward_vsetvls (const bb_info *); /* Phase 3. */ - void merge_successors (const basic_block, const basic_block); - void compute_global_backward_infos (void); + bool merge_successors (const basic_block, const basic_block); + bool backward_demand_fusion (void); + bool forward_demand_fusion (void); + void demand_fusion (void); /* Phase 4. */ void prune_expressions (void); @@ -1866,7 +1885,7 @@ pass_vsetvl::emit_local_forward_vsetvls (const bb_info *bb) } /* Merge all successors of Father except child node. */ -void +bool pass_vsetvl::merge_successors (const basic_block father, const basic_block child) { @@ -1877,7 +1896,8 @@ pass_vsetvl::merge_successors (const basic_block father, || father_info.local_dem.empty_p ()); gcc_assert (father_info.reaching_out.dirty_p () || father_info.reaching_out.empty_p ()); - + + bool changed_p = false; FOR_EACH_EDGE (e, ei, father->succs) { const basic_block succ = e->dest; @@ -1907,12 +1927,15 @@ pass_vsetvl::merge_successors (const basic_block father, father_info.local_dem = new_info; father_info.reaching_out = new_info; + changed_p = true; } + + return changed_p; } /* Compute global backward demanded info. */ -void -pass_vsetvl::compute_global_backward_infos (void) +bool +pass_vsetvl::backward_demand_fusion (void) { /* We compute global infos by backward propagation. We want to have better performance in these following cases: @@ -1939,6 +1962,7 @@ pass_vsetvl::compute_global_backward_infos (void) We backward propagate the first VSETVL into e32,mf2 so that we could be able to eliminate the second VSETVL in LCM. */ + bool changed_p = false; for (const bb_info *bb : crtl->ssa->reverse_bbs ()) { basic_block cfg_bb = bb->cfg_bb (); @@ -1982,9 +2006,10 @@ pass_vsetvl::compute_global_backward_infos (void) block_info.reaching_out.set_dirty (); block_info.reaching_out.set_dirty_pat (new_pat); block_info.local_dem = block_info.reaching_out; + changed_p = true; } - merge_successors (e->src, cfg_bb); + changed_p |= merge_successors (e->src, cfg_bb); } else if (block_info.reaching_out.dirty_p ()) { @@ -2011,6 +2036,7 @@ pass_vsetvl::compute_global_backward_infos (void) new_info.set_dirty_pat (new_pat); block_info.local_dem = new_info; block_info.reaching_out = new_info; + changed_p = true; } else { @@ -2031,9 +2057,99 @@ pass_vsetvl::compute_global_backward_infos (void) if (block_info.local_dem == block_info.reaching_out) block_info.local_dem = new_info; block_info.reaching_out = new_info; + changed_p = true; + } + } + } + return changed_p; +} + +/* Compute global forward demanded info. */ +bool +pass_vsetvl::forward_demand_fusion (void) +{ + /* Enhance the global information propagation especially + backward propagation miss the propagation. + Consider such case: + + bb0 + (TU) + / \ + bb1 bb2 + (TU) (ANY) + existing edge -----> \ / (TU) <----- LCM create this edge. + bb3 + (TU) + + Base on the situation, LCM fails to eliminate the VSETVL instruction and + insert an edge from bb2 to bb3 since we can't backward propagate bb3 into + bb2. To avoid this confusing LCM result and non-optimal codegen, we should + forward propagate information from bb0 to bb2 which is friendly to LCM. */ + bool changed_p = false; + for (const bb_info *bb : crtl->ssa->bbs ()) + { + basic_block cfg_bb = bb->cfg_bb (); + const auto &prop + = m_vector_manager->vector_block_infos[cfg_bb->index].reaching_out; + + /* If there is nothing to propagate, just skip it. */ + if (!prop.valid_or_dirty_p ()) + continue; + + edge e; + edge_iterator ei; + /* Forward propagate to each successor. */ + FOR_EACH_EDGE (e, ei, cfg_bb->succs) + { + auto &local_dem + = m_vector_manager->vector_block_infos[e->dest->index].local_dem; + auto &reaching_out + = m_vector_manager->vector_block_infos[e->dest->index].reaching_out; + + /* It's quite obvious, we don't need to propagate itself. */ + if (e->dest->index == cfg_bb->index) + continue; + + /* If there is nothing to propagate, just skip it. */ + if (!local_dem.valid_or_dirty_p ()) + continue; + + if (prop > local_dem) + { + if (local_dem.dirty_p ()) + { + gcc_assert (local_dem == reaching_out); + rtx dirty_pat + = gen_vsetvl_pat (prop.get_insn ()->rtl (), prop); + local_dem = prop; + local_dem.set_dirty (); + local_dem.set_dirty_pat (dirty_pat); + reaching_out = local_dem; + } + else + { + if (reaching_out == local_dem) + reaching_out.set_demand_info (prop); + local_dem.set_demand_info (prop); + change_vsetvl_insn (local_dem.get_insn (), prop); + } + changed_p = true; } } } + return changed_p; +} + +void +pass_vsetvl::demand_fusion (void) +{ + bool changed_p = true; + while (changed_p) + { + changed_p = false; + changed_p |= backward_demand_fusion (); + changed_p |= forward_demand_fusion (); + } if (dump_file) { @@ -2519,7 +2635,7 @@ pass_vsetvl::lazy_vsetvl (void) /* Phase 3 - Propagate demanded info across blocks. */ if (dump_file) fprintf (dump_file, "\nPhase 3: Demands propagation across blocks\n"); - compute_global_backward_infos (); + demand_fusion (); if (dump_file) m_vector_manager->dump (dump_file); diff --git a/gcc/config/riscv/riscv-vsetvl.h b/gcc/config/riscv/riscv-vsetvl.h index c8218a6ff00..33481a87163 100644 --- a/gcc/config/riscv/riscv-vsetvl.h +++ b/gcc/config/riscv/riscv-vsetvl.h @@ -273,6 +273,7 @@ public: void set_dirty () { m_state = DIRTY; } void set_dirty_pat (rtx pat) { m_dirty_pat = pat; } void set_insn (rtl_ssa::insn_info *insn) { m_insn = insn; } + void set_demand_info (const vector_insn_info &); bool demand_p (enum demand_type type) const { return m_demands[type]; } void demand (enum demand_type type) { m_demands[type] = true; }