/*! * Copyright (c) 2018 by Contributors * \file touch_extractor.h * \brief Extract feature of touch pattern of axes in lowered IR */ #ifndef TVM_AUTOTVM_TOUCH_EXTRACTOR_H_ #define TVM_AUTOTVM_TOUCH_EXTRACTOR_H_ #include <tvm/ir.h> #include <tvm/ir_visitor.h> #include <tvm/api_registry.h> #include <stack> #include <vector> #include <map> #include <string> #include <deque> #include "feature_visitor.h" namespace tvm { namespace autotvm { using TouchedBuffer = std::string; // touch pattern buf[(stride * var) % mod) + other] struct TouchPattern { int64_t stride{0}; int64_t mod{-1}; // -1 for +inf int64_t count{1}; int64_t reuse{1}; int64_t thread_count{0}; // count when move thread axis into innermost int64_t thread_reuse{0}; // reuse ratio move thread axis into innermost }; // all the feature of an iter var struct ItervarFeature { ItervarFeature(VarExpr var, int64_t extent, int nest, AnnotationType ann_type, int64_t topdown, int counter) : length(extent), nest_level(nest), ann(ann_type), topdown_product(topdown), order(counter) {} ItervarFeature() {} // Axis Attributes int64_t length; int nest_level; AnnotationType ann; // one-hot axis type int64_t topdown_product; // accumulative product of axis length, in top-down order int64_t bottomup_product; // accumulative product of axis length, in bottom-up order // bottomup_product = reuse * count for any touched buffer int order; // used for soring axis // Arithmetic feature int add_ct{0}; int mul_ct{0}; int div_ct{0}; // Memory Touch Feature std::unordered_map<TouchedBuffer, TouchPattern> touch_feature; }; // extract iter vars and their touch pattern from ir class TouchExtractor : public FeatureVisitor { public: void Analyze(Stmt stmt) { this->Visit(stmt); } // arithmetic stats void Visit_(const Add *op) { if (op->type.is_float()) itervar_map[itervar_stack_.back()].add_ct++; IRVisitor::Visit_(op); } void Visit_(const Sub *op) { if (op->type.is_float()) itervar_map[itervar_stack_.back()].add_ct++; IRVisitor::Visit_(op); } void Visit_(const Mul *op) { if (op->type.is_float()) itervar_map[itervar_stack_.back()].mul_ct++; IRVisitor::Visit_(op); } void Visit_(const Div *op) { if (op->type.is_float()) itervar_map[itervar_stack_.back()].div_ct++; IRVisitor::Visit_(op); } void Visit_(const Mod *op) { if (op->type.is_float()) itervar_map[itervar_stack_.back()].div_ct++; IRVisitor::Visit_(op); } std::unordered_map<VarExpr, ItervarFeature, tvm::ExprHash, tvm::ExprEqual> itervar_map; private: bool EnterItervar_(VarExpr var, int64_t length, AnnotationType ann_type); void ExitItervar_(); void EnterMem_(VarExpr buffer_var, Expr index); void ExitMem_(); int64_t topdown_product_{1}; std::map<std::string, size_t> buffer_counter_; size_t itervar_counter_{0}; std::deque<VarExpr> itervar_stack_; // use deque instead of stack for indexing std::deque<size_t> skip_stack_size_; using IRVisitor::Visit_; }; } // namespace autotvm } // namespace tvm #endif // TVM_AUTOTVM_TOUCH_EXTRACTOR_H_