DFAPacketizerEmitter.cpp [plain text]
#include "CodeGenTarget.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
#include <list>
#include <map>
#include <string>
using namespace llvm;
namespace {
class DFAPacketizerEmitter {
private:
std::string TargetName;
DenseSet<unsigned> allInsnClasses;
RecordKeeper &Records;
public:
DFAPacketizerEmitter(RecordKeeper &R);
void collectAllInsnClasses(const std::string &Name,
Record *ItinData,
unsigned &NStages,
raw_ostream &OS);
void run(raw_ostream &OS);
};
}
namespace {
class State {
public:
static int currentStateNum;
int stateNum;
bool isInitial;
std::set<unsigned> stateInfo;
typedef std::map<unsigned, State *> TransitionMap;
TransitionMap Transitions;
State();
State(const State &S);
bool operator<(const State &s) const {
return stateNum < s.stateNum;
}
bool canAddInsnClass(unsigned InsnClass) const;
void AddInsnClass(unsigned InsnClass, std::set<unsigned> &PossibleStates);
void addTransition(unsigned InsnClass, State *To);
bool hasTransition(unsigned InsnClass);
};
}
namespace {
class DFA {
public:
DFA();
~DFA();
typedef std::set<State *, less_ptr<State> > StateSet;
StateSet states;
State *currentState;
void initialize();
void addState(State *);
void writeTableAndAPI(raw_ostream &OS, const std::string &ClassName);
};
}
State::State() :
stateNum(currentStateNum++), isInitial(false) {}
State::State(const State &S) :
stateNum(currentStateNum++), isInitial(S.isInitial),
stateInfo(S.stateInfo) {}
DFA::DFA(): currentState(NULL) {}
DFA::~DFA() {
DeleteContainerPointers(states);
}
void State::addTransition(unsigned InsnClass, State *To) {
assert(!Transitions.count(InsnClass) &&
"Cannot have multiple transitions for the same input");
Transitions[InsnClass] = To;
}
bool State::hasTransition(unsigned InsnClass) {
return Transitions.count(InsnClass) > 0;
}
void State::AddInsnClass(unsigned InsnClass,
std::set<unsigned> &PossibleStates) {
for (std::set<unsigned>::iterator SI = stateInfo.begin();
SI != stateInfo.end(); ++SI) {
unsigned thisState = *SI;
DenseSet<unsigned> VisitedResourceStates;
for (unsigned int j = 0; j < sizeof(InsnClass) * 8; ++j) {
if ((0x1 << j) & InsnClass) {
unsigned ResultingResourceState = thisState | (0x1 << j);
if ((ResultingResourceState != thisState) &&
(VisitedResourceStates.count(ResultingResourceState) == 0)) {
VisitedResourceStates.insert(ResultingResourceState);
PossibleStates.insert(ResultingResourceState);
}
}
}
}
}
bool State::canAddInsnClass(unsigned InsnClass) const {
for (std::set<unsigned>::const_iterator SI = stateInfo.begin();
SI != stateInfo.end(); ++SI) {
if (~*SI & InsnClass)
return true;
}
return false;
}
void DFA::initialize() {
assert(currentState && "Missing current state");
currentState->isInitial = true;
}
void DFA::addState(State *S) {
assert(!states.count(S) && "State already exists");
states.insert(S);
}
int State::currentStateNum = 0;
DFAPacketizerEmitter::DFAPacketizerEmitter(RecordKeeper &R):
TargetName(CodeGenTarget(R).getName()),
allInsnClasses(), Records(R) {}
void DFA::writeTableAndAPI(raw_ostream &OS, const std::string &TargetName) {
static const std::string SentinelEntry = "{-1, -1}";
DFA::StateSet::iterator SI = states.begin();
std::vector<int> StateEntry(states.size());
OS << "namespace llvm {\n\n";
OS << "const int " << TargetName << "DFAStateInputTable[][2] = {\n";
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 (State::TransitionMap::iterator
II = (*SI)->Transitions.begin(), IE = (*SI)->Transitions.end();
II != IE; ++II) {
OS << "{" << II->first << ", "
<< II->second->stateNum
<< "}, ";
}
ValidTransitions += (*SI)->Transitions.size();
if (ValidTransitions == StateEntry[i]) {
OS << SentinelEntry << ",";
++ValidTransitions;
}
OS << "\n";
}
OS << SentinelEntry << "\n";
OS << "};\n\n";
OS << "const unsigned int " << TargetName << "DFAStateEntryTable[] = {\n";
for (unsigned i = 0; i < states.size(); ++i)
OS << StateEntry[i] << ", ";
OS << ValidTransitions << ", ";
OS << "\n};\n";
OS << "} // namespace\n";
std::string SubTargetClassName = TargetName + "GenSubtargetInfo";
OS << "\n" << "#include \"llvm/CodeGen/DFAPacketizer.h\"\n";
OS << "namespace llvm {\n";
OS << "DFAPacketizer *" << SubTargetClassName << "::"
<< "createDFAPacketizer(const InstrItineraryData *IID) const {\n"
<< " return new DFAPacketizer(IID, " << TargetName
<< "DFAStateInputTable, " << TargetName << "DFAStateEntryTable);\n}\n\n";
OS << "} // End llvm namespace \n";
}
void DFAPacketizerEmitter::collectAllInsnClasses(const std::string &Name,
Record *ItinData,
unsigned &NStages,
raw_ostream &OS) {
std::vector<Record*> ProcItinList =
Records.getAllDerivedDefinitions("ProcessorItineraries");
if (ProcItinList.size() < 2)
return;
std::map<std::string, unsigned> NameToBitsMap;
for (unsigned i = 0, N = ProcItinList.size(); i < N; ++i) {
Record *Proc = ProcItinList[i];
std::vector<Record*> FUs = Proc->getValueAsListOfDefs("FU");
for (unsigned i = 0, N = FUs.size(); i < N; ++i)
NameToBitsMap[FUs[i]->getName()] = (unsigned) (1U << i);
}
const std::vector<Record*> &StageList =
ItinData->getValueAsListOfDefs("Stages");
NStages = StageList.size();
unsigned UnitBitValue = 0;
for (unsigned i = 0; i < NStages; ++i) {
const Record *Stage = StageList[i];
const std::vector<Record*> &UnitList =
Stage->getValueAsListOfDefs("Units");
for (unsigned j = 0, M = UnitList.size(); j < M; ++j) {
std::string UnitName = UnitList[j]->getName();
assert(NameToBitsMap.count(UnitName));
UnitBitValue |= NameToBitsMap[UnitName];
}
if (UnitBitValue != 0)
allInsnClasses.insert(UnitBitValue);
}
}
void DFAPacketizerEmitter::run(raw_ostream &OS) {
std::vector<Record*> ProcItinList =
Records.getAllDerivedDefinitions("ProcessorItineraries");
for (unsigned i = 0, N = ProcItinList.size(); i < N; i++) {
Record *Proc = ProcItinList[i];
const std::string &Name = Proc->getName();
if (Name == "NoItineraries")
continue;
unsigned NItinClasses =
Records.getAllDerivedDefinitions("InstrItinClass").size();
if (NItinClasses == 0)
return;
std::vector<Record*> ItinDataList = Proc->getValueAsListOfDefs("IID");
for (unsigned j = 0, M = ItinDataList.size(); j < M; j++) {
Record *ItinData = ItinDataList[j];
unsigned NStages;
collectAllInsnClasses(Name, ItinData, NStages, OS);
}
}
DFA D;
State *Initial = new State;
Initial->isInitial = true;
Initial->stateInfo.insert(0x0);
D.addState(Initial);
SmallVector<State*, 32> WorkList;
std::map<std::set<unsigned>, State*> Visited;
WorkList.push_back(Initial);
while (!WorkList.empty()) {
State *current = WorkList.pop_back_val();
for (DenseSet<unsigned>::iterator CI = allInsnClasses.begin(),
CE = allInsnClasses.end(); CI != CE; ++CI) {
unsigned InsnClass = *CI;
std::set<unsigned> NewStateResources;
if (!current->hasTransition(InsnClass) &&
current->canAddInsnClass(InsnClass)) {
State *NewState = NULL;
current->AddInsnClass(InsnClass, NewStateResources);
assert(NewStateResources.size() && "New states must be generated");
std::map<std::set<unsigned>, State*>::iterator VI;
if ((VI = Visited.find(NewStateResources)) != Visited.end())
NewState = VI->second;
else {
NewState = new State;
NewState->stateInfo = NewStateResources;
D.addState(NewState);
Visited[NewStateResources] = NewState;
WorkList.push_back(NewState);
}
current->addTransition(InsnClass, NewState);
}
}
}
D.writeTableAndAPI(OS, TargetName);
}
namespace llvm {
void EmitDFAPacketizer(RecordKeeper &RK, raw_ostream &OS) {
emitSourceFileHeader("Target DFA Packetizer Tables", OS);
DFAPacketizerEmitter(RK).run(OS);
}
}