1 //===- DFAPacketizerEmitter.h - Packetization DFA for a VLIW machine-------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This class parses the Schedule.td file and produces an API that can be used 11 // to reason about whether an instruction can be added to a packet on a VLIW 12 // architecture. The class internally generates a deterministic finite 13 // automaton (DFA) that models all possible mappings of machine instructions 14 // to functional units as instructions are added to a packet. 15 // 16 //===----------------------------------------------------------------------===// 17 18 #include "llvm/ADT/DenseSet.h" 19 #include "llvm/TableGen/TableGenBackend.h" 20 #include <map> 21 #include <string> 22 23 namespace llvm { 24 // 25 // class DFAGen: class that generates and prints out the DFA for resource 26 // tracking. 27 // 28 class DFAGen : public TableGenBackend { 29 private: 30 std::string TargetName; 31 // 32 // allInsnClasses is the set of all possible resources consumed by an 33 // InstrStage. 34 // 35 DenseSet<unsigned> allInsnClasses; 36 RecordKeeper &Records; 37 38 public: 39 DFAGen(RecordKeeper &R); 40 41 // 42 // collectAllInsnClasses: Populate allInsnClasses which is a set of units 43 // used in each stage. 44 // 45 void collectAllInsnClasses(const std::string &Name, 46 Record *ItinData, 47 unsigned &NStages, 48 raw_ostream &OS); 49 50 void run(raw_ostream &OS); 51 }; 52 } 53