//
//===----------------------------------------------------------------------===//
//
-// This tablegen backend emits a "fast" instruction selector.
+// This tablegen backend emits code for use by the "fast" instruction
+// selection algorithm. See the comments at the top of
+// lib/CodeGen/SelectionDAG/FastISel.cpp for background.
//
-// This instruction selection method is designed to emit very poor code
-// quickly. Also, it is not designed to do much lowering, so most illegal
-// types (e.g. i64 on 32-bit targets) and operations (e.g. calls) are not
-// supported and cannot easily be added. Blocks containing operations
-// that are not supported need to be handled by a more capable selector,
-// such as the SelectionDAG selector.
+// This file scans through the target's tablegen instruction-info files
+// and extracts instructions with obvious-looking patterns, and it emits
+// code to look up these instructions by type and operator.
//
-// The intended use for "fast" instruction selection is "-O0" mode
-// compilation, where the quality of the generated code is irrelevant when
-// weighed against the speed at which the code can be generated.
-//
-// If compile time is so important, you might wonder why we don't just
-// skip codegen all-together, emit LLVM bytecode files, and execute them
-// with an interpreter. The answer is that it would complicate linking and
-// debugging, and also because that isn't how a compiler is expected to
-// work in some circles.
-//
-// If you need better generated code or more lowering than what this
-// instruction selector provides, use the SelectionDAG (DAGISel) instruction
-// selector instead. If you're looking here because SelectionDAG isn't fast
-// enough, consider looking into improving the SelectionDAG infastructure
-// instead. At the time of this writing there remain several major
-// opportunities for improvement.
-//
//===----------------------------------------------------------------------===//
-#include "FastISelEmitter.h"
-#include "Record.h"
+#include "CodeGenDAGPatterns.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringSwitch.h"
#include "llvm/Support/Debug.h"
-#include "llvm/Support/Streams.h"
-#include "llvm/ADT/VectorExtras.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/TableGen/Error.h"
+#include "llvm/TableGen/Record.h"
+#include "llvm/TableGen/TableGenBackend.h"
using namespace llvm;
+
+/// InstructionMemo - This class holds additional information about an
+/// instruction needed to emit code for it.
+///
namespace {
+struct InstructionMemo {
+ std::string Name;
+ const CodeGenRegisterClass *RC;
+ std::string SubRegNo;
+ std::vector<std::string>* PhysRegs;
+ std::string PredicateCheck;
+};
+} // End anonymous namespace
+
+/// ImmPredicateSet - This uniques predicates (represented as a string) and
+/// gives them unique (small) integer ID's that start at 0.
+namespace {
+class ImmPredicateSet {
+ DenseMap<TreePattern *, unsigned> ImmIDs;
+ std::vector<TreePredicateFn> PredsByName;
+public:
+
+ unsigned getIDFor(TreePredicateFn Pred) {
+ unsigned &Entry = ImmIDs[Pred.getOrigPatFragRecord()];
+ if (Entry == 0) {
+ PredsByName.push_back(Pred);
+ Entry = PredsByName.size();
+ }
+ return Entry-1;
+ }
+
+ const TreePredicateFn &getPredicate(unsigned i) {
+ assert(i < PredsByName.size());
+ return PredsByName[i];
+ }
+
+ typedef std::vector<TreePredicateFn>::const_iterator iterator;
+ iterator begin() const { return PredsByName.begin(); }
+ iterator end() const { return PredsByName.end(); }
+
+};
+} // End anonymous namespace
/// OperandsSignature - This class holds a description of a list of operand
/// types. It has utility methods for emitting text based on the operands.
///
+namespace {
struct OperandsSignature {
- std::vector<std::string> Operands;
+ class OpKind {
+ enum { OK_Reg, OK_FP, OK_Imm, OK_Invalid = -1 };
+ char Repr;
+ public:
+
+ OpKind() : Repr(OK_Invalid) {}
+
+ bool operator<(OpKind RHS) const { return Repr < RHS.Repr; }
+ bool operator==(OpKind RHS) const { return Repr == RHS.Repr; }
+
+ static OpKind getReg() { OpKind K; K.Repr = OK_Reg; return K; }
+ static OpKind getFP() { OpKind K; K.Repr = OK_FP; return K; }
+ static OpKind getImm(unsigned V) {
+ assert((unsigned)OK_Imm+V < 128 &&
+ "Too many integer predicates for the 'Repr' char");
+ OpKind K; K.Repr = OK_Imm+V; return K;
+ }
+
+ bool isReg() const { return Repr == OK_Reg; }
+ bool isFP() const { return Repr == OK_FP; }
+ bool isImm() const { return Repr >= OK_Imm; }
+
+ unsigned getImmCode() const { assert(isImm()); return Repr-OK_Imm; }
+
+ void printManglingSuffix(raw_ostream &OS, ImmPredicateSet &ImmPredicates,
+ bool StripImmCodes) const {
+ if (isReg())
+ OS << 'r';
+ else if (isFP())
+ OS << 'f';
+ else {
+ OS << 'i';
+ if (!StripImmCodes)
+ if (unsigned Code = getImmCode())
+ OS << "_" << ImmPredicates.getPredicate(Code-1).getFnName();
+ }
+ }
+ };
+
+
+ SmallVector<OpKind, 3> Operands;
bool operator<(const OperandsSignature &O) const {
return Operands < O.Operands;
}
+ bool operator==(const OperandsSignature &O) const {
+ return Operands == O.Operands;
+ }
bool empty() const { return Operands.empty(); }
+ bool hasAnyImmediateCodes() const {
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i)
+ if (Operands[i].isImm() && Operands[i].getImmCode() != 0)
+ return true;
+ return false;
+ }
+
+ /// getWithoutImmCodes - Return a copy of this with any immediate codes forced
+ /// to zero.
+ OperandsSignature getWithoutImmCodes() const {
+ OperandsSignature Result;
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i)
+ if (!Operands[i].isImm())
+ Result.Operands.push_back(Operands[i]);
+ else
+ Result.Operands.push_back(OpKind::getImm(0));
+ return Result;
+ }
+
+ void emitImmediatePredicate(raw_ostream &OS, ImmPredicateSet &ImmPredicates) {
+ bool EmittedAnything = false;
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
+ if (!Operands[i].isImm()) continue;
+
+ unsigned Code = Operands[i].getImmCode();
+ if (Code == 0) continue;
+
+ if (EmittedAnything)
+ OS << " &&\n ";
+
+ TreePredicateFn PredFn = ImmPredicates.getPredicate(Code-1);
+
+ // Emit the type check.
+ OS << "VT == "
+ << getEnumName(PredFn.getOrigPatFragRecord()->getTree(0)->getType(0))
+ << " && ";
+
+
+ OS << PredFn.getFnName() << "(imm" << i <<')';
+ EmittedAnything = true;
+ }
+ }
+
/// initialize - Examine the given pattern and initialize the contents
/// of the Operands array accordingly. Return true if all the operands
/// are supported, false otherwise.
///
- bool initialize(TreePatternNode *InstPatNode,
- const CodeGenTarget &Target,
- MVT::SimpleValueType VT) {
+ bool initialize(TreePatternNode *InstPatNode, const CodeGenTarget &Target,
+ MVT::SimpleValueType VT,
+ ImmPredicateSet &ImmediatePredicates,
+ const CodeGenRegisterClass *OrigDstRC) {
+ if (InstPatNode->isLeaf())
+ return false;
+
+ if (InstPatNode->getOperator()->getName() == "imm") {
+ Operands.push_back(OpKind::getImm(0));
+ return true;
+ }
+
+ if (InstPatNode->getOperator()->getName() == "fpimm") {
+ Operands.push_back(OpKind::getFP());
+ return true;
+ }
+
+ const CodeGenRegisterClass *DstRC = nullptr;
+
for (unsigned i = 0, e = InstPatNode->getNumChildren(); i != e; ++i) {
TreePatternNode *Op = InstPatNode->getChild(i);
- if (!Op->isLeaf())
- return false;
+
+ // Handle imm operands specially.
+ if (!Op->isLeaf() && Op->getOperator()->getName() == "imm") {
+ unsigned PredNo = 0;
+ if (!Op->getPredicateFns().empty()) {
+ TreePredicateFn PredFn = Op->getPredicateFns()[0];
+ // If there is more than one predicate weighing in on this operand
+ // then we don't handle it. This doesn't typically happen for
+ // immediates anyway.
+ if (Op->getPredicateFns().size() > 1 ||
+ !PredFn.isImmediatePattern())
+ return false;
+ // Ignore any instruction with 'FastIselShouldIgnore', these are
+ // not needed and just bloat the fast instruction selector. For
+ // example, X86 doesn't need to generate code to match ADD16ri8 since
+ // ADD16ri will do just fine.
+ Record *Rec = PredFn.getOrigPatFragRecord()->getRecord();
+ if (Rec->getValueAsBit("FastIselShouldIgnore"))
+ return false;
+
+ PredNo = ImmediatePredicates.getIDFor(PredFn)+1;
+ }
+
+ // Handle unmatched immediate sizes here.
+ //if (Op->getType(0) != VT)
+ // return false;
+
+ Operands.push_back(OpKind::getImm(PredNo));
+ continue;
+ }
+
+
// For now, filter out any operand with a predicate.
- if (!Op->getPredicateFn().empty())
+ // For now, filter out any operand with multiple values.
+ if (!Op->getPredicateFns().empty() || Op->getNumTypes() != 1)
return false;
- DefInit *OpDI = dynamic_cast<DefInit*>(Op->getLeafValue());
+
+ if (!Op->isLeaf()) {
+ if (Op->getOperator()->getName() == "fpimm") {
+ Operands.push_back(OpKind::getFP());
+ continue;
+ }
+ // For now, ignore other non-leaf nodes.
+ return false;
+ }
+
+ assert(Op->hasTypeSet(0) && "Type infererence not done?");
+
+ // For now, all the operands must have the same type (if they aren't
+ // immediates). Note that this causes us to reject variable sized shifts
+ // on X86.
+ if (Op->getType(0) != VT)
+ return false;
+
+ DefInit *OpDI = dyn_cast<DefInit>(Op->getLeafValue());
if (!OpDI)
return false;
Record *OpLeafRec = OpDI->getDef();
- // For now, only accept register operands.
- if (!OpLeafRec->isSubClassOf("RegisterClass"))
+
+ // For now, the only other thing we accept is register operands.
+ const CodeGenRegisterClass *RC = nullptr;
+ if (OpLeafRec->isSubClassOf("RegisterOperand"))
+ OpLeafRec = OpLeafRec->getValueAsDef("RegClass");
+ if (OpLeafRec->isSubClassOf("RegisterClass"))
+ RC = &Target.getRegisterClass(OpLeafRec);
+ else if (OpLeafRec->isSubClassOf("Register"))
+ RC = Target.getRegBank().getRegClassForRegister(OpLeafRec);
+ else if (OpLeafRec->isSubClassOf("ValueType")) {
+ RC = OrigDstRC;
+ } else
return false;
- // For now, require the register operands' register classes to all
- // be the same.
- const CodeGenRegisterClass *RC = &Target.getRegisterClass(OpLeafRec);
+
+ // For now, this needs to be a register class of some sort.
if (!RC)
return false;
- // For now, all the operands must have the same type.
- if (Op->getTypeNum(0) != VT)
- return false;
- Operands.push_back("r");
+
+ // For now, all the operands must have the same register class or be
+ // a strict subclass of the destination.
+ if (DstRC) {
+ if (DstRC != RC && !DstRC->hasSubClass(RC))
+ return false;
+ } else
+ DstRC = RC;
+ Operands.push_back(OpKind::getReg());
}
return true;
}
- void PrintParameters(std::ostream &OS) const {
+ void PrintParameters(raw_ostream &OS) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
- if (Operands[i] == "r") {
- OS << "unsigned Op" << i;
+ if (Operands[i].isReg()) {
+ OS << "unsigned Op" << i << ", bool Op" << i << "IsKill";
+ } else if (Operands[i].isImm()) {
+ OS << "uint64_t imm" << i;
+ } else if (Operands[i].isFP()) {
+ OS << "const ConstantFP *f" << i;
} else {
- assert("Unknown operand kind!");
- abort();
+ llvm_unreachable("Unknown operand kind!");
}
if (i + 1 != e)
OS << ", ";
}
}
- void PrintArguments(std::ostream &OS) const {
+ void PrintArguments(raw_ostream &OS,
+ const std::vector<std::string> &PR) const {
+ assert(PR.size() == Operands.size());
+ bool PrintedArg = false;
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
+ if (PR[i] != "")
+ // Implicit physical register operand.
+ continue;
+
+ if (PrintedArg)
+ OS << ", ";
+ if (Operands[i].isReg()) {
+ OS << "Op" << i << ", Op" << i << "IsKill";
+ PrintedArg = true;
+ } else if (Operands[i].isImm()) {
+ OS << "imm" << i;
+ PrintedArg = true;
+ } else if (Operands[i].isFP()) {
+ OS << "f" << i;
+ PrintedArg = true;
+ } else {
+ llvm_unreachable("Unknown operand kind!");
+ }
+ }
+ }
+
+ void PrintArguments(raw_ostream &OS) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
- if (Operands[i] == "r") {
- OS << "Op" << i;
+ if (Operands[i].isReg()) {
+ OS << "Op" << i << ", Op" << i << "IsKill";
+ } else if (Operands[i].isImm()) {
+ OS << "imm" << i;
+ } else if (Operands[i].isFP()) {
+ OS << "f" << i;
} else {
- assert("Unknown operand kind!");
- abort();
+ llvm_unreachable("Unknown operand kind!");
}
if (i + 1 != e)
OS << ", ";
}
}
- void PrintManglingSuffix(std::ostream &OS) const {
+
+ void PrintManglingSuffix(raw_ostream &OS, const std::vector<std::string> &PR,
+ ImmPredicateSet &ImmPredicates,
+ bool StripImmCodes = false) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
- OS << Operands[i];
+ if (PR[i] != "")
+ // Implicit physical register operand. e.g. Instruction::Mul expect to
+ // select to a binary op. On x86, mul may take a single operand with
+ // the other operand being implicit. We must emit something that looks
+ // like a binary instruction except for the very inner fastEmitInst_*
+ // call.
+ continue;
+ Operands[i].printManglingSuffix(OS, ImmPredicates, StripImmCodes);
}
}
-};
-/// InstructionMemo - This class holds additional information about an
-/// instruction needed to emit code for it.
-///
-struct InstructionMemo {
- std::string Name;
- const CodeGenRegisterClass *RC;
+ void PrintManglingSuffix(raw_ostream &OS, ImmPredicateSet &ImmPredicates,
+ bool StripImmCodes = false) const {
+ for (unsigned i = 0, e = Operands.size(); i != e; ++i)
+ Operands[i].printManglingSuffix(OS, ImmPredicates, StripImmCodes);
+ }
};
+} // End anonymous namespace
-}
+namespace {
+class FastISelMap {
+ // A multimap is needed instead of a "plain" map because the key is
+ // the instruction's complexity (an int) and they are not unique.
+ typedef std::multimap<int, InstructionMemo> PredMap;
+ typedef std::map<MVT::SimpleValueType, PredMap> RetPredMap;
+ typedef std::map<MVT::SimpleValueType, RetPredMap> TypeRetPredMap;
+ typedef std::map<std::string, TypeRetPredMap> OpcodeTypeRetPredMap;
+ typedef std::map<OperandsSignature, OpcodeTypeRetPredMap>
+ OperandsOpcodeTypeRetPredMap;
+
+ OperandsOpcodeTypeRetPredMap SimplePatterns;
+
+ // This is used to check that there are no duplicate predicates
+ typedef std::multimap<std::string, bool> PredCheckMap;
+ typedef std::map<MVT::SimpleValueType, PredCheckMap> RetPredCheckMap;
+ typedef std::map<MVT::SimpleValueType, RetPredCheckMap> TypeRetPredCheckMap;
+ typedef std::map<std::string, TypeRetPredCheckMap> OpcodeTypeRetPredCheckMap;
+ typedef std::map<OperandsSignature, OpcodeTypeRetPredCheckMap>
+ OperandsOpcodeTypeRetPredCheckMap;
+
+ OperandsOpcodeTypeRetPredCheckMap SimplePatternsCheck;
+
+ std::map<OperandsSignature, std::vector<OperandsSignature> >
+ SignaturesWithConstantForms;
+
+ std::string InstNS;
+ ImmPredicateSet ImmediatePredicates;
+public:
+ explicit FastISelMap(std::string InstNS);
+
+ void collectPatterns(CodeGenDAGPatterns &CGP);
+ void printImmediatePredicates(raw_ostream &OS);
+ void printFunctionDefinitions(raw_ostream &OS);
+private:
+ void emitInstructionCode(raw_ostream &OS,
+ const OperandsSignature &Operands,
+ const PredMap &PM,
+ const std::string &RetVTName);
+};
+} // End anonymous namespace
static std::string getOpcodeName(Record *Op, CodeGenDAGPatterns &CGP) {
return CGP.getSDNodeInfo(Op).getEnumName();
return OpName;
}
-void FastISelEmitter::run(std::ostream &OS) {
- EmitSourceFileHeader("\"Fast\" Instruction Selector for the " +
- CGP.getTargetInfo().getName() + " target", OS);
-
+FastISelMap::FastISelMap(std::string instns)
+ : InstNS(instns) {
+}
+
+static std::string PhyRegForNode(TreePatternNode *Op,
+ const CodeGenTarget &Target) {
+ std::string PhysReg;
+
+ if (!Op->isLeaf())
+ return PhysReg;
+
+ Record *OpLeafRec = cast<DefInit>(Op->getLeafValue())->getDef();
+ if (!OpLeafRec->isSubClassOf("Register"))
+ return PhysReg;
+
+ PhysReg += cast<StringInit>(OpLeafRec->getValue("Namespace")->getValue())
+ ->getValue();
+ PhysReg += "::";
+ PhysReg += Target.getRegBank().getReg(OpLeafRec)->getName();
+ return PhysReg;
+}
+
+void FastISelMap::collectPatterns(CodeGenDAGPatterns &CGP) {
const CodeGenTarget &Target = CGP.getTargetInfo();
-
- // Get the namespace to insert instructions into. Make sure not to pick up
- // "TargetInstrInfo" by accidentally getting the namespace off the PHI
- // instruction or something.
- std::string InstNS;
- for (CodeGenTarget::inst_iterator i = Target.inst_begin(),
- e = Target.inst_end(); i != e; ++i) {
- InstNS = i->second.Namespace;
- if (InstNS != "TargetInstrInfo")
- break;
- }
- OS << "namespace llvm {\n";
- OS << "namespace " << InstNS << " {\n";
- OS << "class FastISel;\n";
- OS << "}\n";
- OS << "}\n";
- OS << "\n";
-
- if (!InstNS.empty()) InstNS += "::";
-
- typedef std::map<MVT::SimpleValueType, InstructionMemo> TypeMap;
- typedef std::map<std::string, TypeMap> OpcodeTypeMap;
- typedef std::map<OperandsSignature, OpcodeTypeMap> OperandsOpcodeTypeMap;
- OperandsOpcodeTypeMap SimplePatterns;
-
- // Create the supported type signatures.
- OperandsSignature KnownOperands;
- SimplePatterns[KnownOperands] = OpcodeTypeMap();
- KnownOperands.Operands.push_back("r");
- SimplePatterns[KnownOperands] = OpcodeTypeMap();
- KnownOperands.Operands.push_back("r");
- SimplePatterns[KnownOperands] = OpcodeTypeMap();
+ // Determine the target's namespace name.
+ InstNS = Target.getInstNamespace() + "::";
+ assert(InstNS.size() > 2 && "Can't determine target-specific namespace!");
+ // Scan through all the patterns and record the simple ones.
for (CodeGenDAGPatterns::ptm_iterator I = CGP.ptm_begin(),
E = CGP.ptm_end(); I != E; ++I) {
const PatternToMatch &Pattern = *I;
Record *Op = Dst->getOperator();
if (!Op->isSubClassOf("Instruction"))
continue;
- CodeGenInstruction &II = CGP.getTargetInfo().getInstruction(Op->getName());
- if (II.OperandList.empty())
+ CodeGenInstruction &II = CGP.getTargetInfo().getInstruction(Op);
+ if (II.Operands.empty())
+ continue;
+
+ // For now, ignore multi-instruction patterns.
+ bool MultiInsts = false;
+ for (unsigned i = 0, e = Dst->getNumChildren(); i != e; ++i) {
+ TreePatternNode *ChildOp = Dst->getChild(i);
+ if (ChildOp->isLeaf())
+ continue;
+ if (ChildOp->getOperator()->isSubClassOf("Instruction")) {
+ MultiInsts = true;
+ break;
+ }
+ }
+ if (MultiInsts)
continue;
// For now, ignore instructions where the first operand is not an
// output register.
- Record *Op0Rec = II.OperandList[0].Rec;
- if (!Op0Rec->isSubClassOf("RegisterClass"))
- continue;
- const CodeGenRegisterClass *DstRC = &Target.getRegisterClass(Op0Rec);
- if (!DstRC)
- continue;
+ const CodeGenRegisterClass *DstRC = nullptr;
+ std::string SubRegNo;
+ if (Op->getName() != "EXTRACT_SUBREG") {
+ Record *Op0Rec = II.Operands[0].Rec;
+ if (Op0Rec->isSubClassOf("RegisterOperand"))
+ Op0Rec = Op0Rec->getValueAsDef("RegClass");
+ if (!Op0Rec->isSubClassOf("RegisterClass"))
+ continue;
+ DstRC = &Target.getRegisterClass(Op0Rec);
+ if (!DstRC)
+ continue;
+ } else {
+ // If this isn't a leaf, then continue since the register classes are
+ // a bit too complicated for now.
+ if (!Dst->getChild(1)->isLeaf()) continue;
+
+ DefInit *SR = dyn_cast<DefInit>(Dst->getChild(1)->getLeafValue());
+ if (SR)
+ SubRegNo = getQualifiedName(SR->getDef());
+ else
+ SubRegNo = Dst->getChild(1)->getLeafValue()->getAsString();
+ }
// Inspect the pattern.
TreePatternNode *InstPatNode = Pattern.getSrcPattern();
if (!InstPatNode) continue;
if (InstPatNode->isLeaf()) continue;
+ // Ignore multiple result nodes for now.
+ if (InstPatNode->getNumTypes() > 1) continue;
+
Record *InstPatOp = InstPatNode->getOperator();
std::string OpcodeName = getOpcodeName(InstPatOp, CGP);
- MVT::SimpleValueType VT = InstPatNode->getTypeNum(0);
-
- // For now, filter out instructions which just set a register to
- // an Operand or an immediate, like MOV32ri.
- if (InstPatOp->isSubClassOf("Operand"))
- continue;
- if (InstPatOp->getName() == "imm" ||
- InstPatOp->getName() == "fpimm")
- continue;
+ MVT::SimpleValueType RetVT = MVT::isVoid;
+ if (InstPatNode->getNumTypes()) RetVT = InstPatNode->getType(0);
+ MVT::SimpleValueType VT = RetVT;
+ if (InstPatNode->getNumChildren()) {
+ assert(InstPatNode->getChild(0)->getNumTypes() == 1);
+ VT = InstPatNode->getChild(0)->getType(0);
+ }
// For now, filter out any instructions with predicates.
- if (!InstPatNode->getPredicateFn().empty())
+ if (!InstPatNode->getPredicateFns().empty())
continue;
// Check all the operands.
OperandsSignature Operands;
- if (!Operands.initialize(InstPatNode, Target, VT))
+ if (!Operands.initialize(InstPatNode, Target, VT, ImmediatePredicates,
+ DstRC))
continue;
- // If it's not a known signature, ignore it.
- if (!SimplePatterns.count(Operands))
+ std::vector<std::string>* PhysRegInputs = new std::vector<std::string>();
+ if (InstPatNode->getOperator()->getName() == "imm" ||
+ InstPatNode->getOperator()->getName() == "fpimm")
+ PhysRegInputs->push_back("");
+ else {
+ // Compute the PhysRegs used by the given pattern, and check that
+ // the mapping from the src to dst patterns is simple.
+ bool FoundNonSimplePattern = false;
+ unsigned DstIndex = 0;
+ for (unsigned i = 0, e = InstPatNode->getNumChildren(); i != e; ++i) {
+ std::string PhysReg = PhyRegForNode(InstPatNode->getChild(i), Target);
+ if (PhysReg.empty()) {
+ if (DstIndex >= Dst->getNumChildren() ||
+ Dst->getChild(DstIndex)->getName() !=
+ InstPatNode->getChild(i)->getName()) {
+ FoundNonSimplePattern = true;
+ break;
+ }
+ ++DstIndex;
+ }
+
+ PhysRegInputs->push_back(PhysReg);
+ }
+
+ if (Op->getName() != "EXTRACT_SUBREG" && DstIndex < Dst->getNumChildren())
+ FoundNonSimplePattern = true;
+
+ if (FoundNonSimplePattern)
+ continue;
+ }
+
+ // Check if the operands match one of the patterns handled by FastISel.
+ std::string ManglingSuffix;
+ raw_string_ostream SuffixOS(ManglingSuffix);
+ Operands.PrintManglingSuffix(SuffixOS, ImmediatePredicates, true);
+ SuffixOS.flush();
+ if (!StringSwitch<bool>(ManglingSuffix)
+ .Cases("", "r", "rr", "ri", "rf", true)
+ .Cases("rri", "i", "f", true)
+ .Default(false))
continue;
+ // Get the predicate that guards this pattern.
+ std::string PredicateCheck = Pattern.getPredicateCheck();
+
// Ok, we found a pattern that we can handle. Remember it.
- {
- InstructionMemo Memo = {
- Pattern.getDstPattern()->getOperator()->getName(),
- DstRC
- };
- SimplePatterns[Operands][OpcodeName][VT] = Memo;
+ InstructionMemo Memo = {
+ Pattern.getDstPattern()->getOperator()->getName(),
+ DstRC,
+ SubRegNo,
+ PhysRegInputs,
+ PredicateCheck
+ };
+
+ int complexity = Pattern.getPatternComplexity(CGP);
+
+ if (SimplePatternsCheck[Operands][OpcodeName][VT]
+ [RetVT].count(PredicateCheck)) {
+ PrintFatalError(Pattern.getSrcRecord()->getLoc(),
+ "Duplicate predicate in FastISel table!");
+ }
+ SimplePatternsCheck[Operands][OpcodeName][VT][RetVT].insert(
+ std::make_pair(PredicateCheck, true));
+
+ // Note: Instructions with the same complexity will appear in the order
+ // that they are encountered.
+ SimplePatterns[Operands][OpcodeName][VT][RetVT].insert(
+ std::make_pair(complexity, Memo));
+
+ // If any of the operands were immediates with predicates on them, strip
+ // them down to a signature that doesn't have predicates so that we can
+ // associate them with the stripped predicate version.
+ if (Operands.hasAnyImmediateCodes()) {
+ SignaturesWithConstantForms[Operands.getWithoutImmCodes()]
+ .push_back(Operands);
}
}
+}
- OS << "#include \"llvm/CodeGen/FastISel.h\"\n";
- OS << "\n";
- OS << "namespace llvm {\n";
- OS << "\n";
-
- // Declare the target FastISel class.
- OS << "class " << InstNS << "FastISel : public llvm::FastISel {\n";
- for (OperandsOpcodeTypeMap::const_iterator OI = SimplePatterns.begin(),
- OE = SimplePatterns.end(); OI != OE; ++OI) {
- const OperandsSignature &Operands = OI->first;
- const OpcodeTypeMap &OTM = OI->second;
+void FastISelMap::printImmediatePredicates(raw_ostream &OS) {
+ if (ImmediatePredicates.begin() == ImmediatePredicates.end())
+ return;
- for (OpcodeTypeMap::const_iterator I = OTM.begin(), E = OTM.end();
- I != E; ++I) {
- const std::string &Opcode = I->first;
- const TypeMap &TM = I->second;
+ OS << "\n// FastEmit Immediate Predicate functions.\n";
+ for (ImmPredicateSet::iterator I = ImmediatePredicates.begin(),
+ E = ImmediatePredicates.end(); I != E; ++I) {
+ OS << "static bool " << I->getFnName() << "(int64_t Imm) {\n";
+ OS << I->getImmediatePredicateCode() << "\n}\n";
+ }
- for (TypeMap::const_iterator TI = TM.begin(), TE = TM.end();
- TI != TE; ++TI) {
- MVT::SimpleValueType VT = TI->first;
+ OS << "\n\n";
+}
- OS << " unsigned FastEmit_" << getLegalCName(Opcode)
- << "_" << getLegalCName(getName(VT)) << "(";
- Operands.PrintParameters(OS);
- OS << ");\n";
+void FastISelMap::emitInstructionCode(raw_ostream &OS,
+ const OperandsSignature &Operands,
+ const PredMap &PM,
+ const std::string &RetVTName) {
+ // Emit code for each possible instruction. There may be
+ // multiple if there are subtarget concerns. A reverse iterator
+ // is used to produce the ones with highest complexity first.
+
+ bool OneHadNoPredicate = false;
+ for (PredMap::const_reverse_iterator PI = PM.rbegin(), PE = PM.rend();
+ PI != PE; ++PI) {
+ const InstructionMemo &Memo = PI->second;
+ std::string PredicateCheck = Memo.PredicateCheck;
+
+ if (PredicateCheck.empty()) {
+ assert(!OneHadNoPredicate &&
+ "Multiple instructions match and more than one had "
+ "no predicate!");
+ OneHadNoPredicate = true;
+ } else {
+ if (OneHadNoPredicate) {
+ // FIXME: This should be a PrintError once the x86 target
+ // fixes PR21575.
+ PrintWarning("Multiple instructions match and one with no "
+ "predicate came before one with a predicate! "
+ "name:" + Memo.Name + " predicate: " +
+ PredicateCheck);
}
+ OS << " if (" + PredicateCheck + ") {\n";
+ OS << " ";
+ }
+
+ for (unsigned i = 0; i < Memo.PhysRegs->size(); ++i) {
+ if ((*Memo.PhysRegs)[i] != "")
+ OS << " BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, "
+ << "TII.get(TargetOpcode::COPY), "
+ << (*Memo.PhysRegs)[i] << ").addReg(Op" << i << ");\n";
+ }
- OS << " unsigned FastEmit_" << getLegalCName(Opcode)
- << "(MVT::SimpleValueType VT";
+ OS << " return fastEmitInst_";
+ if (Memo.SubRegNo.empty()) {
+ Operands.PrintManglingSuffix(OS, *Memo.PhysRegs,
+ ImmediatePredicates, true);
+ OS << "(" << InstNS << Memo.Name << ", ";
+ OS << "&" << InstNS << Memo.RC->getName() << "RegClass";
if (!Operands.empty())
OS << ", ";
- Operands.PrintParameters(OS);
+ Operands.PrintArguments(OS, *Memo.PhysRegs);
OS << ");\n";
+ } else {
+ OS << "extractsubreg(" << RetVTName
+ << ", Op0, Op0IsKill, " << Memo.SubRegNo << ");\n";
}
- OS << " unsigned FastEmit_";
- Operands.PrintManglingSuffix(OS);
- OS << "(MVT::SimpleValueType VT, ISD::NodeType Opcode";
- if (!Operands.empty())
- OS << ", ";
- Operands.PrintParameters(OS);
- OS << ");\n";
+ if (!PredicateCheck.empty()) {
+ OS << " }\n";
+ }
}
- OS << "public:\n";
- OS << " FastISel(MachineBasicBlock *mbb, MachineFunction *mf, ";
- OS << "const TargetInstrInfo *tii) : llvm::FastISel(mbb, mf, tii) {}\n";
- OS << "};\n";
- OS << "\n";
-
- // Define the target FastISel creation function.
- OS << "llvm::FastISel *" << InstNS
- << "createFastISel(MachineBasicBlock *mbb, MachineFunction *mf, ";
- OS << "const TargetInstrInfo *tii) {\n";
- OS << " return new " << InstNS << "FastISel(mbb, mf, tii);\n";
+ // Return 0 if all of the possibilities had predicates but none
+ // were satisfied.
+ if (!OneHadNoPredicate)
+ OS << " return 0;\n";
OS << "}\n";
OS << "\n";
+}
+
+void FastISelMap::printFunctionDefinitions(raw_ostream &OS) {
// Now emit code for all the patterns that we collected.
- for (OperandsOpcodeTypeMap::const_iterator OI = SimplePatterns.begin(),
+ for (OperandsOpcodeTypeRetPredMap::const_iterator OI = SimplePatterns.begin(),
OE = SimplePatterns.end(); OI != OE; ++OI) {
const OperandsSignature &Operands = OI->first;
- const OpcodeTypeMap &OTM = OI->second;
+ const OpcodeTypeRetPredMap &OTM = OI->second;
- for (OpcodeTypeMap::const_iterator I = OTM.begin(), E = OTM.end();
+ for (OpcodeTypeRetPredMap::const_iterator I = OTM.begin(), E = OTM.end();
I != E; ++I) {
const std::string &Opcode = I->first;
- const TypeMap &TM = I->second;
+ const TypeRetPredMap &TM = I->second;
OS << "// FastEmit functions for " << Opcode << ".\n";
OS << "\n";
// Emit one function for each opcode,type pair.
- for (TypeMap::const_iterator TI = TM.begin(), TE = TM.end();
+ for (TypeRetPredMap::const_iterator TI = TM.begin(), TE = TM.end();
TI != TE; ++TI) {
MVT::SimpleValueType VT = TI->first;
- const InstructionMemo &Memo = TI->second;
-
- OS << "unsigned " << InstNS << "FastISel::FastEmit_"
- << getLegalCName(Opcode)
- << "_" << getLegalCName(getName(VT)) << "(";
- Operands.PrintParameters(OS);
- OS << ") {\n";
- OS << " return FastEmitInst_";
- Operands.PrintManglingSuffix(OS);
- OS << "(" << InstNS << Memo.Name << ", ";
- OS << InstNS << Memo.RC->getName() << "RegisterClass";
- if (!Operands.empty())
- OS << ", ";
- Operands.PrintArguments(OS);
- OS << ");\n";
- OS << "}\n";
- OS << "\n";
+ const RetPredMap &RM = TI->second;
+ if (RM.size() != 1) {
+ for (RetPredMap::const_iterator RI = RM.begin(), RE = RM.end();
+ RI != RE; ++RI) {
+ MVT::SimpleValueType RetVT = RI->first;
+ const PredMap &PM = RI->second;
+
+ OS << "unsigned fastEmit_"
+ << getLegalCName(Opcode)
+ << "_" << getLegalCName(getName(VT))
+ << "_" << getLegalCName(getName(RetVT)) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(";
+ Operands.PrintParameters(OS);
+ OS << ") {\n";
+
+ emitInstructionCode(OS, Operands, PM, getName(RetVT));
+ }
+
+ // Emit one function for the type that demultiplexes on return type.
+ OS << "unsigned fastEmit_"
+ << getLegalCName(Opcode) << "_"
+ << getLegalCName(getName(VT)) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(MVT RetVT";
+ if (!Operands.empty())
+ OS << ", ";
+ Operands.PrintParameters(OS);
+ OS << ") {\nswitch (RetVT.SimpleTy) {\n";
+ for (RetPredMap::const_iterator RI = RM.begin(), RE = RM.end();
+ RI != RE; ++RI) {
+ MVT::SimpleValueType RetVT = RI->first;
+ OS << " case " << getName(RetVT) << ": return fastEmit_"
+ << getLegalCName(Opcode) << "_" << getLegalCName(getName(VT))
+ << "_" << getLegalCName(getName(RetVT)) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(";
+ Operands.PrintArguments(OS);
+ OS << ");\n";
+ }
+ OS << " default: return 0;\n}\n}\n\n";
+
+ } else {
+ // Non-variadic return type.
+ OS << "unsigned fastEmit_"
+ << getLegalCName(Opcode) << "_"
+ << getLegalCName(getName(VT)) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(MVT RetVT";
+ if (!Operands.empty())
+ OS << ", ";
+ Operands.PrintParameters(OS);
+ OS << ") {\n";
+
+ OS << " if (RetVT.SimpleTy != " << getName(RM.begin()->first)
+ << ")\n return 0;\n";
+
+ const PredMap &PM = RM.begin()->second;
+
+ emitInstructionCode(OS, Operands, PM, "RetVT");
+ }
}
// Emit one function for the opcode that demultiplexes based on the type.
- OS << "unsigned " << InstNS << "FastISel::FastEmit_"
- << getLegalCName(Opcode) << "(MVT::SimpleValueType VT";
+ OS << "unsigned fastEmit_"
+ << getLegalCName(Opcode) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(MVT VT, MVT RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
OS << ") {\n";
- OS << " switch (VT) {\n";
- for (TypeMap::const_iterator TI = TM.begin(), TE = TM.end();
+ OS << " switch (VT.SimpleTy) {\n";
+ for (TypeRetPredMap::const_iterator TI = TM.begin(), TE = TM.end();
TI != TE; ++TI) {
MVT::SimpleValueType VT = TI->first;
std::string TypeName = getName(VT);
- OS << " case " << TypeName << ": return FastEmit_"
- << getLegalCName(Opcode) << "_" << getLegalCName(TypeName) << "(";
+ OS << " case " << TypeName << ": return fastEmit_"
+ << getLegalCName(Opcode) << "_" << getLegalCName(TypeName) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(RetVT";
+ if (!Operands.empty())
+ OS << ", ";
Operands.PrintArguments(OS);
OS << ");\n";
}
OS << "\n";
}
+ OS << "// Top-level FastEmit function.\n";
+ OS << "\n";
+
// Emit one function for the operand signature that demultiplexes based
// on opcode and type.
- OS << "unsigned " << InstNS << "FastISel::FastEmit_";
- Operands.PrintManglingSuffix(OS);
- OS << "(MVT::SimpleValueType VT, ISD::NodeType Opcode";
+ OS << "unsigned fastEmit_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(MVT VT, MVT RetVT, unsigned Opcode";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
- OS << ") {\n";
+ OS << ") ";
+ if (!Operands.hasAnyImmediateCodes())
+ OS << "override ";
+ OS << "{\n";
+
+ // If there are any forms of this signature available that operate on
+ // constrained forms of the immediate (e.g., 32-bit sext immediate in a
+ // 64-bit operand), check them first.
+
+ std::map<OperandsSignature, std::vector<OperandsSignature> >::iterator MI
+ = SignaturesWithConstantForms.find(Operands);
+ if (MI != SignaturesWithConstantForms.end()) {
+ // Unique any duplicates out of the list.
+ std::sort(MI->second.begin(), MI->second.end());
+ MI->second.erase(std::unique(MI->second.begin(), MI->second.end()),
+ MI->second.end());
+
+ // Check each in order it was seen. It would be nice to have a good
+ // relative ordering between them, but we're not going for optimality
+ // here.
+ for (unsigned i = 0, e = MI->second.size(); i != e; ++i) {
+ OS << " if (";
+ MI->second[i].emitImmediatePredicate(OS, ImmediatePredicates);
+ OS << ")\n if (unsigned Reg = fastEmit_";
+ MI->second[i].PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(VT, RetVT, Opcode";
+ if (!MI->second[i].empty())
+ OS << ", ";
+ MI->second[i].PrintArguments(OS);
+ OS << "))\n return Reg;\n\n";
+ }
+
+ // Done with this, remove it.
+ SignaturesWithConstantForms.erase(MI);
+ }
+
OS << " switch (Opcode) {\n";
- for (OpcodeTypeMap::const_iterator I = OTM.begin(), E = OTM.end();
+ for (OpcodeTypeRetPredMap::const_iterator I = OTM.begin(), E = OTM.end();
I != E; ++I) {
const std::string &Opcode = I->first;
- OS << " case " << Opcode << ": return FastEmit_"
- << getLegalCName(Opcode) << "(VT";
+ OS << " case " << Opcode << ": return fastEmit_"
+ << getLegalCName(Opcode) << "_";
+ Operands.PrintManglingSuffix(OS, ImmediatePredicates);
+ OS << "(VT, RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintArguments(OS);
OS << "\n";
}
- OS << "}\n";
+ // TODO: SignaturesWithConstantForms should be empty here.
+}
+
+namespace llvm {
+
+void EmitFastISel(RecordKeeper &RK, raw_ostream &OS) {
+ CodeGenDAGPatterns CGP(RK);
+ const CodeGenTarget &Target = CGP.getTargetInfo();
+ emitSourceFileHeader("\"Fast\" Instruction Selector for the " +
+ Target.getName() + " target", OS);
+
+ // Determine the target's namespace name.
+ std::string InstNS = Target.getInstNamespace() + "::";
+ assert(InstNS.size() > 2 && "Can't determine target-specific namespace!");
+
+ FastISelMap F(InstNS);
+ F.collectPatterns(CGP);
+ F.printImmediatePredicates(OS);
+ F.printFunctionDefinitions(OS);
}
-// todo: really filter out Constants
+} // End llvm namespace