junrushao1994 commented on a change in pull request #9940: URL: https://github.com/apache/tvm/pull/9940#discussion_r785480957
########## File path: src/meta_schedule/schedule_rule/random_compute_location.cc ########## @@ -0,0 +1,135 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +#include "../utils.h" + +namespace tvm { +namespace meta_schedule { +class RandomComputeLocationNode : public ScheduleRuleNode { + public: + // Inherited from ScheduleRuleNode + void InitializeWithTuneContext(const TuneContext& context) final {} + + // Inherited from ScheduleRuleNode + Array<tir::Schedule> Apply(const tir::Schedule& sch, const tir::BlockRV& block_rv) final { + if (!CheckConditions(sch, block_rv)) { + return {sch}; + } + + // Step 1. If the producer of the input block needs a random compute-at location (specified by + // the annotation), we colect the producer first, and transform the producer block later. + // - The reason we collect the producer before transforming the input block is that, if the + // decision of Sample-Compute-Location is "compute-inline" for the input block, we can no longer + // access the input block. Hence we collect its producer ahead of time. + // - Note that only single producer is allowed in this case. + Array<tir::BlockRV> producers{nullptr}; + if (tir::HasAnn(sch->GetSRef(block_rv), tir::attr::meta_schedule_random_compute_producer, + true)) { + producers = sch->GetProducers(block_rv); + sch->Unannotate(block_rv, tir::attr::meta_schedule_random_compute_producer); + ICHECK_EQ(producers.size(), 1); + } + + // Step 2. Transform the input block. + tir::Schedule res = RandomlyComputeAt(sch, block_rv); + + // Step 3. Transform the producer block if compute-location sampling is needed. + if (producers.defined()) { + res = RandomlyComputeAt(res, producers[0]); + } + + return {res}; + } + + private: + bool CheckConditions(const tir::Schedule sch, const tir::BlockRV& block_rv) const { + const tir::StmtSRef& block_sref = sch->GetSRef(block_rv); + const tir::BlockNode* block = TVM_SREF_TO_BLOCK(block, block_sref); + + // Cond 1. The block is not the root block. + if (block_sref->parent == nullptr) { + return false; + } + // Cond 2. The block should be the direct child block of the root block. + if (GetScopeRoot(sch->state(), block_sref, // + /*require_stage_pipeline=*/false, // + /*require_subtree_compact_dataflow=*/false) + ->parent != nullptr) { + return false; + } + // Cond 3 & 4. The block has at least one outer loop, and the outermost loop has only one child + // block. + Array<tir::StmtSRef> loop_srefs = tir::GetLoops(block_sref); + if (loop_srefs.empty()) { + return false; + } + if (tir::GetChildBlockSRefOnSRefTree(sch->state(), loop_srefs[0]).size() > 1) { + return false; + } + // Cond 5. The block is not tiled. We check this condition by examine the block's annotation. + if (tir::GetAnn<String>(block_sref, tir::attr::meta_schedule_tiling_structure).defined()) { + return false; + } + // Cond 6. The block has at lease one consumer. + if (tir::GetConsumers(sch->state(), sch->GetSRef(block_rv)).empty()) { + return false; + } + return true; + } + + /*! + * \brief Keep sampling a compute-at location for the input block until success. + * \param sch The TIR schedule + * \param block_rv The block whose compute-at location is to be sampled + * \return The TIR schedule after transformation + */ + tir::Schedule RandomlyComputeAt(const tir::Schedule& sch, const tir::BlockRV& block_rv) { + for (;;) { + tir::LoopRV compute_at_loc = sch->SampleComputeLocation(block_rv); + try { + sch->ComputeAt(block_rv, compute_at_loc, true); + } catch (const dmlc::Error& e) { + // ComputeAt fails, cleanup the following before re-try: + // 1) trace: instruction & decisions + // 2) sym_tab + sch->trace().value()->Pop(); + sch->RemoveRV(compute_at_loc); + continue; + } + break; + } Review comment: Note that ScheduleRules are run only once before the search, which takes much less than 1 second - there isn't need for optimizing their performance -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
