hzfan commented on a change in pull request #5092: [PASS] dtype rewrite for indexing variables URL: https://github.com/apache/incubator-tvm/pull/5092#discussion_r395155241
########## File path: src/tir/pass/rewrite_datatype.cc ########## @@ -0,0 +1,322 @@ +/* + * 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. + */ + +/*! + * \file rewrite_datatype.cc + */ + +#include <tvm/tir/ir_pass.h> +#include <tvm/tir/op.h> +#include "../../arith/ir_mutator_with_analyzer.h" +#include "../../arith/ir_visitor_with_analyzer.h" + +namespace tvm { +namespace tir { + +using arith::Analyzer; +using arith::IRMutatorWithAnalyzer; +using arith::ConstIntBound; + +class DataTypeRewriter; + +class DataTypeVisitor final : public StmtExprVisitor { + public: + void VisitExpr(const PrimExpr& e) { + if (e.dtype().is_int()) { + int bits = 64; + if (e.dtype().bits() <= 32 || + analyzer_.CanProve(e <= max_value(DataType::Int(32)) && + e >= min_value(DataType::Int(32)))) { + bits = 32; + } + int tmp = bits_; + bits_ = bits > bits_ ? bits : bits_; + StmtExprVisitor::VisitExpr(e); + bits_ = tmp; + } else { + StmtExprVisitor::VisitExpr(e); + } + } + + void VisitStmt_(const ForNode* op) { + analyzer_.Bind(op->loop_var, + Range::make_by_min_extent(op->min, op->extent)); + vset_.insert(op->loop_var.as<Object>()); + vextent_[op->loop_var.as<Object>()] = op->extent.dtype(); + return StmtExprVisitor::VisitStmt_(op); + } + + void VisitStmt_(const AttrStmtNode* op) { + if (op->attr_key == attr::thread_extent || + op->attr_key == attr::virtual_thread) { + IterVar iv = Downcast<IterVar>(op->node); + CHECK_NE(iv->thread_tag.length(), 0U); + analyzer_.Bind(iv->var, + Range::make_by_min_extent(0, op->value)); + vset_.insert(iv->var.as<Object>()); + vextent_[iv->var.as<Object>()] = op->value.dtype(); + StmtExprVisitor::VisitStmt_(op); + } else { + StmtExprVisitor::VisitStmt_(op); + } + } + + void VisitExpr_(const ReduceNode* op) { + // Setup the domain information before simplification. + for (const IterVar& iv : op->axis) { + analyzer_.Bind(iv->var, iv->dom); + vset_.insert(iv->var.as<Object>()); + vextent_[iv->var.as<Object>()] = iv->dom->extent.dtype(); + } + // Recursively call simplification when necessary. + StmtExprVisitor::VisitExpr_(op); + } + + void VisitExpr_(const VarNode* op) { + if (vset_.find(op) != vset_.end()) { + int bits = std::min(vextent_[op].bits(), bits_); + if (vmap.find(op) == vmap.end()) { + vmap[op] = op->dtype.with_bits(bits); + } else { + vmap[op] = op->dtype.with_bits(std::max(vmap[op].bits(), bits)); + } + } + StmtExprVisitor::VisitExpr_(op); + } + + void VisitExpr_(const IntImmNode* op) { + if (op->dtype.is_int()) { + int bits = std::min(op->dtype.bits(), bits_); + if (vmap.find(op) == vmap.end()) { + vmap[op] = op->dtype.with_bits(bits); + } else { + vmap[op] = op->dtype.with_bits(std::max(vmap[op].bits(), bits)); + } + } + StmtExprVisitor::VisitExpr_(op); + } + + void VisitExpr_(const CastNode* op) { + if (op->dtype.is_int()) { + int bits = std::min(op->dtype.bits(), bits_); + if (vmap.find(op) == vmap.end()) { + vmap[op] = op->dtype.with_bits(bits); + } else { + vmap[op] = op->dtype.with_bits(std::max(vmap[op].bits(), bits)); + } + } + StmtExprVisitor::VisitExpr_(op); + } + + // the narrowed datatype of Var and IntImm + std::unordered_map<const Object*, DataType> vmap; + + protected: + // internal analyzer + arith::Analyzer analyzer_; + + private: + // the maximum bits of all containing expressions + int bits_; + // the vars to be rewritten + std::unordered_set<const Object*> vset_; Review comment: Agree. `vset_` removed ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
