X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=utils%2FTableGen%2FDFAPacketizerEmitter.cpp;h=5060b6e9ce7c0b059fac364b563fa3b1a849ef68;hb=47f0e3f434e2e43f951c3a826c40906cb15b7285;hp=8bfecead6d2ecd59f2d0e303fce2436d30eece86;hpb=87dc7a4c8d21bd638465881f3b6d091f22d9767c;p=oota-llvm.git diff --git a/utils/TableGen/DFAPacketizerEmitter.cpp b/utils/TableGen/DFAPacketizerEmitter.cpp index 8bfecead6d2..5060b6e9ce7 100644 --- a/utils/TableGen/DFAPacketizerEmitter.cpp +++ b/utils/TableGen/DFAPacketizerEmitter.cpp @@ -17,6 +17,7 @@ #include "CodeGenTarget.h" #include "llvm/ADT/DenseSet.h" +#include "llvm/ADT/STLExtras.h" #include "llvm/TableGen/Record.h" #include "llvm/TableGen/TableGenBackend.h" #include @@ -74,17 +75,26 @@ public: // Another way of thinking about this transition is we are mapping a NDFA with // two states [0x01] and [0x10] into a DFA with a single state [0x01, 0x10]. // +// A State instance also contains a collection of transitions from that state: +// a map from inputs to new states. // namespace { class State { public: static int currentStateNum; - int stateNum; - bool isInitial; - std::set stateInfo; + // stateNum is the only member used for equality/ordering, all other members + // can be mutated even in const State objects. + const int stateNum; + mutable bool isInitial; + mutable std::set stateInfo; + typedef std::map TransitionMap; + mutable TransitionMap Transitions; State(); - State(const State &S); + + bool operator<(const State &s) const { + return stateNum < s.stateNum; + } // // canAddInsnClass - Returns true if an instruction of type InsnClass is a @@ -99,39 +109,19 @@ class State { // AddInsnClass - Return all combinations of resource reservation // which are possible from this state (PossibleStates). // - void AddInsnClass(unsigned InsnClass, std::set &PossibleStates); -}; -} // End anonymous namespace. - - -namespace { -struct Transition { - public: - static int currentTransitionNum; - int transitionNum; - State *from; - unsigned input; - State *to; - - Transition(State *from_, unsigned input_, State *to_); -}; -} // End anonymous namespace. - - -// -// Comparators to keep set of states sorted. -// -namespace { -struct ltState { - bool operator()(const State *s1, const State *s2) const; -}; - -struct ltTransition { - bool operator()(const Transition *s1, const Transition *s2) const; + void AddInsnClass(unsigned InsnClass, std::set &PossibleStates) const; + // + // addTransition - Add a transition from this state given the input InsnClass + // + void addTransition(unsigned InsnClass, const State *To) const; + // + // hasTransition - Returns true if there is a transition from this state + // given the input InsnClass + // + bool hasTransition(unsigned InsnClass) const; }; } // End anonymous namespace. - // // class DFA: deterministic finite automaton for processor resource tracking. // @@ -141,34 +131,15 @@ public: DFA(); // Set of states. Need to keep this sorted to emit the transition table. - std::set states; + typedef std::set StateSet; + StateSet states; - // Map from a state to the list of transitions with that state as source. - std::map, ltState> - stateTransitions; State *currentState; - // Highest valued Input seen. - unsigned LargestInput; - // // Modify the DFA. // - void initialize(); - void addState(State *); - void addTransition(Transition *); - - // - // getTransition - Return the state when a transition is made from - // State From with Input I. If a transition is not found, return NULL. - // - State *getTransition(State *, unsigned); - - // - // isValidTransition: Predicate that checks if there is a valid transition - // from state From on input InsnClass. - // - bool isValidTransition(State *From, unsigned InsnClass); + const State &newState(); // // writeTable: Print out a table representing the DFA. @@ -179,32 +150,28 @@ public: // -// Constructors for State, Transition, and DFA +// Constructors and destructors for State and DFA // State::State() : stateNum(currentStateNum++), isInitial(false) {} +DFA::DFA(): currentState(nullptr) {} -State::State(const State &S) : - stateNum(currentStateNum++), isInitial(S.isInitial), - stateInfo(S.stateInfo) {} - - -Transition::Transition(State *from_, unsigned input_, State *to_) : - transitionNum(currentTransitionNum++), from(from_), input(input_), - to(to_) {} - - -DFA::DFA() : - LargestInput(0) {} - - -bool ltState::operator()(const State *s1, const State *s2) const { - return (s1->stateNum < s2->stateNum); +// +// addTransition - Add a transition from this state given the input InsnClass +// +void State::addTransition(unsigned InsnClass, const State *To) const { + assert(!Transitions.count(InsnClass) && + "Cannot have multiple transitions for the same input"); + Transitions[InsnClass] = To; } -bool ltTransition::operator()(const Transition *s1, const Transition *s2) const { - return (s1->input < s2->input); +// +// hasTransition - Returns true if there is a transition from this state +// given the input InsnClass +// +bool State::hasTransition(unsigned InsnClass) const { + return Transitions.count(InsnClass) > 0; } // @@ -212,7 +179,7 @@ bool ltTransition::operator()(const Transition *s1, const Transition *s2) const // which are possible from this state (PossibleStates). // void State::AddInsnClass(unsigned InsnClass, - std::set &PossibleStates) { + std::set &PossibleStates) const { // // Iterate over all resource states in currentState. // @@ -271,58 +238,14 @@ bool State::canAddInsnClass(unsigned InsnClass) const { } -void DFA::initialize() { - currentState->isInitial = true; -} - - -void DFA::addState(State *S) { - assert(!states.count(S) && "State already exists"); - states.insert(S); -} - - -void DFA::addTransition(Transition *T) { - // Update LargestInput. - if (T->input > LargestInput) - LargestInput = T->input; - - // Add the new transition. - bool Added = stateTransitions[T->from].insert(T).second; - assert(Added && "Cannot have multiple states for the same input"); - (void)Added; -} - - -// -// getTransition - Return the state when a transition is made from -// State From with Input I. If a transition is not found, return NULL. -// -State *DFA::getTransition(State *From, unsigned I) { - // Do we have a transition from state From? - if (!stateTransitions.count(From)) - return NULL; - - // Do we have a transition from state From with Input I? - Transition TVal(NULL, I, NULL); - // Do not count this temporal instance - Transition::currentTransitionNum--; - std::set::iterator T = - stateTransitions[From].find(&TVal); - if (T != stateTransitions[From].end()) - return (*T)->to; - - return NULL; -} - - -bool DFA::isValidTransition(State *From, unsigned InsnClass) { - return (getTransition(From, InsnClass) != NULL); +const State &DFA::newState() { + auto IterPair = states.insert(State()); + assert(IterPair.second && "State already exists"); + return *IterPair.first; } int State::currentStateNum = 0; -int Transition::currentTransitionNum = 0; DFAPacketizerEmitter::DFAPacketizerEmitter(RecordKeeper &R): TargetName(CodeGenTarget(R).getName()), @@ -341,7 +264,8 @@ DFAPacketizerEmitter::DFAPacketizerEmitter(RecordKeeper &R): // // void DFA::writeTableAndAPI(raw_ostream &OS, const std::string &TargetName) { - std::set::iterator SI = states.begin(); + static const std::string SentinelEntry = "{-1, -1}"; + DFA::StateSet::iterator SI = states.begin(); // This table provides a map to the beginning of the transitions for State s // in DFAStateInputTable. std::vector StateEntry(states.size()); @@ -353,28 +277,31 @@ void DFA::writeTableAndAPI(raw_ostream &OS, const std::string &TargetName) { // to construct the StateEntry table. int ValidTransitions = 0; for (unsigned i = 0; i < states.size(); ++i, ++SI) { + assert ((SI->stateNum == (int) i) && "Mismatch in state numbers"); StateEntry[i] = ValidTransitions; - for (unsigned j = 0; j <= LargestInput; ++j) { - assert (((*SI)->stateNum == (int) i) && "Mismatch in state numbers"); - State *To = getTransition(*SI, j); - if (To == NULL) - continue; - - OS << "{" << j << ", " - << To->stateNum + for (State::TransitionMap::iterator + II = SI->Transitions.begin(), IE = SI->Transitions.end(); + II != IE; ++II) { + OS << "{" << II->first << ", " + << II->second->stateNum << "}, "; - ++ValidTransitions; } + ValidTransitions += SI->Transitions.size(); // If there are no valid transitions from this stage, we need a sentinel // transition. if (ValidTransitions == StateEntry[i]) { - OS << "{-1, -1},"; + OS << SentinelEntry << ","; ++ValidTransitions; } OS << "\n"; } + + // Print out a sentinel entry at the end of the StateInputTable. This is + // needed to iterate over StateInputTable in DFAPacketizer::ReadTable() + OS << SentinelEntry << "\n"; + OS << "};\n\n"; OS << "const unsigned int " << TargetName << "DFAStateEntryTable[] = {\n"; @@ -383,6 +310,9 @@ void DFA::writeTableAndAPI(raw_ostream &OS, const std::string &TargetName) { for (unsigned i = 0; i < states.size(); ++i) OS << StateEntry[i] << ", "; + // Print out the index to the sentinel entry in StateInputTable + OS << ValidTransitions << ", "; + OS << "\n};\n"; OS << "} // namespace\n"; @@ -502,12 +432,11 @@ void DFAPacketizerEmitter::run(raw_ostream &OS) { // Run a worklist algorithm to generate the DFA. // DFA D; - State *Initial = new State; + const State *Initial = &D.newState(); Initial->isInitial = true; Initial->stateInfo.insert(0x0); - D.addState(Initial); - SmallVector WorkList; - std::map, State*> Visited; + SmallVector WorkList; + std::map, const State*> Visited; WorkList.push_back(Initial); @@ -529,7 +458,7 @@ void DFAPacketizerEmitter::run(raw_ostream &OS) { // Add S' to Visited // while (!WorkList.empty()) { - State *current = WorkList.pop_back_val(); + const State *current = WorkList.pop_back_val(); for (DenseSet::iterator CI = allInsnClasses.begin(), CE = allInsnClasses.end(); CI != CE; ++CI) { unsigned InsnClass = *CI; @@ -539,30 +468,27 @@ void DFAPacketizerEmitter::run(raw_ostream &OS) { // If we haven't already created a transition for this input // and the state can accommodate this InsnClass, create a transition. // - if (!D.getTransition(current, InsnClass) && + if (!current->hasTransition(InsnClass) && current->canAddInsnClass(InsnClass)) { - State *NewState = NULL; + const State *NewState; current->AddInsnClass(InsnClass, NewStateResources); - assert(NewStateResources.size() && "New states must be generated"); + assert(!NewStateResources.empty() && "New states must be generated"); // // If we have seen this state before, then do not create a new state. // // - std::map, State*>::iterator VI; - if ((VI = Visited.find(NewStateResources)) != Visited.end()) + auto VI = Visited.find(NewStateResources); + if (VI != Visited.end()) NewState = VI->second; else { - NewState = new State; + NewState = &D.newState(); NewState->stateInfo = NewStateResources; - D.addState(NewState); Visited[NewStateResources] = NewState; WorkList.push_back(NewState); } - - Transition *NewTransition = new Transition(current, InsnClass, - NewState); - D.addTransition(NewTransition); + + current->addTransition(InsnClass, NewState); } } }