llvm-6502/utils/TableGen/InstrInfoEmitter.cpp
Jakob Stoklund Olesen f2c64ef519 Add an MCID::Select flag and TII hooks for optimizing selects.
Select instructions pick one of two virtual registers based on a
condition, like x86 cmov. On targets like ARM that support predication,
selects can sometimes be eliminated by predicating the instruction
defining one of the operands.

Teach PeepholeOptimizer to recognize select instructions, and ask the
target to optimize them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162059 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-16 23:11:47 +00:00

422 lines
15 KiB
C++

//===- InstrInfoEmitter.cpp - Generate a Instruction Set Desc. ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend is responsible for emitting a description of the target
// instruction set for the code generator.
//
//===----------------------------------------------------------------------===//
#include "CodeGenDAGPatterns.h"
#include "CodeGenSchedule.h"
#include "CodeGenTarget.h"
#include "SequenceToOffsetTable.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
#include <algorithm>
#include <cstdio>
#include <map>
#include <vector>
using namespace llvm;
namespace {
class InstrInfoEmitter {
RecordKeeper &Records;
CodeGenDAGPatterns CDP;
const CodeGenSchedModels &SchedModels;
public:
InstrInfoEmitter(RecordKeeper &R):
Records(R), CDP(R), SchedModels(CDP.getTargetInfo().getSchedModels()) {}
// run - Output the instruction set description.
void run(raw_ostream &OS);
private:
void emitEnums(raw_ostream &OS);
typedef std::map<std::vector<std::string>, unsigned> OperandInfoMapTy;
void emitRecord(const CodeGenInstruction &Inst, unsigned Num,
Record *InstrInfo,
std::map<std::vector<Record*>, unsigned> &EL,
const OperandInfoMapTy &OpInfo,
raw_ostream &OS);
// Operand information.
void EmitOperandInfo(raw_ostream &OS, OperandInfoMapTy &OperandInfoIDs);
std::vector<std::string> GetOperandInfo(const CodeGenInstruction &Inst);
};
} // End anonymous namespace
static void PrintDefList(const std::vector<Record*> &Uses,
unsigned Num, raw_ostream &OS) {
OS << "static const uint16_t ImplicitList" << Num << "[] = { ";
for (unsigned i = 0, e = Uses.size(); i != e; ++i)
OS << getQualifiedName(Uses[i]) << ", ";
OS << "0 };\n";
}
//===----------------------------------------------------------------------===//
// Operand Info Emission.
//===----------------------------------------------------------------------===//
std::vector<std::string>
InstrInfoEmitter::GetOperandInfo(const CodeGenInstruction &Inst) {
std::vector<std::string> Result;
for (unsigned i = 0, e = Inst.Operands.size(); i != e; ++i) {
// Handle aggregate operands and normal operands the same way by expanding
// either case into a list of operands for this op.
std::vector<CGIOperandList::OperandInfo> OperandList;
// This might be a multiple operand thing. Targets like X86 have
// registers in their multi-operand operands. It may also be an anonymous
// operand, which has a single operand, but no declared class for the
// operand.
DagInit *MIOI = Inst.Operands[i].MIOperandInfo;
if (!MIOI || MIOI->getNumArgs() == 0) {
// Single, anonymous, operand.
OperandList.push_back(Inst.Operands[i]);
} else {
for (unsigned j = 0, e = Inst.Operands[i].MINumOperands; j != e; ++j) {
OperandList.push_back(Inst.Operands[i]);
Record *OpR = dynamic_cast<DefInit*>(MIOI->getArg(j))->getDef();
OperandList.back().Rec = OpR;
}
}
for (unsigned j = 0, e = OperandList.size(); j != e; ++j) {
Record *OpR = OperandList[j].Rec;
std::string Res;
if (OpR->isSubClassOf("RegisterOperand"))
OpR = OpR->getValueAsDef("RegClass");
if (OpR->isSubClassOf("RegisterClass"))
Res += getQualifiedName(OpR) + "RegClassID, ";
else if (OpR->isSubClassOf("PointerLikeRegClass"))
Res += utostr(OpR->getValueAsInt("RegClassKind")) + ", ";
else
// -1 means the operand does not have a fixed register class.
Res += "-1, ";
// Fill in applicable flags.
Res += "0";
// Ptr value whose register class is resolved via callback.
if (OpR->isSubClassOf("PointerLikeRegClass"))
Res += "|(1<<MCOI::LookupPtrRegClass)";
// Predicate operands. Check to see if the original unexpanded operand
// was of type PredicateOperand.
if (Inst.Operands[i].Rec->isSubClassOf("PredicateOperand"))
Res += "|(1<<MCOI::Predicate)";
// Optional def operands. Check to see if the original unexpanded operand
// was of type OptionalDefOperand.
if (Inst.Operands[i].Rec->isSubClassOf("OptionalDefOperand"))
Res += "|(1<<MCOI::OptionalDef)";
// Fill in operand type.
Res += ", MCOI::";
assert(!Inst.Operands[i].OperandType.empty() && "Invalid operand type.");
Res += Inst.Operands[i].OperandType;
// Fill in constraint info.
Res += ", ";
const CGIOperandList::ConstraintInfo &Constraint =
Inst.Operands[i].Constraints[j];
if (Constraint.isNone())
Res += "0";
else if (Constraint.isEarlyClobber())
Res += "(1 << MCOI::EARLY_CLOBBER)";
else {
assert(Constraint.isTied());
Res += "((" + utostr(Constraint.getTiedOperand()) +
" << 16) | (1 << MCOI::TIED_TO))";
}
Result.push_back(Res);
}
}
return Result;
}
void InstrInfoEmitter::EmitOperandInfo(raw_ostream &OS,
OperandInfoMapTy &OperandInfoIDs) {
// ID #0 is for no operand info.
unsigned OperandListNum = 0;
OperandInfoIDs[std::vector<std::string>()] = ++OperandListNum;
OS << "\n";
const CodeGenTarget &Target = CDP.getTargetInfo();
for (CodeGenTarget::inst_iterator II = Target.inst_begin(),
E = Target.inst_end(); II != E; ++II) {
std::vector<std::string> OperandInfo = GetOperandInfo(**II);
unsigned &N = OperandInfoIDs[OperandInfo];
if (N != 0) continue;
N = ++OperandListNum;
OS << "static const MCOperandInfo OperandInfo" << N << "[] = { ";
for (unsigned i = 0, e = OperandInfo.size(); i != e; ++i)
OS << "{ " << OperandInfo[i] << " }, ";
OS << "};\n";
}
}
//===----------------------------------------------------------------------===//
// Main Output.
//===----------------------------------------------------------------------===//
// run - Emit the main instruction description records for the target...
void InstrInfoEmitter::run(raw_ostream &OS) {
emitSourceFileHeader("Target Instruction Enum Values", OS);
emitEnums(OS);
emitSourceFileHeader("Target Instruction Descriptors", OS);
OS << "\n#ifdef GET_INSTRINFO_MC_DESC\n";
OS << "#undef GET_INSTRINFO_MC_DESC\n";
OS << "namespace llvm {\n\n";
CodeGenTarget &Target = CDP.getTargetInfo();
const std::string &TargetName = Target.getName();
Record *InstrInfo = Target.getInstructionSet();
// Keep track of all of the def lists we have emitted already.
std::map<std::vector<Record*>, unsigned> EmittedLists;
unsigned ListNumber = 0;
// Emit all of the instruction's implicit uses and defs.
for (CodeGenTarget::inst_iterator II = Target.inst_begin(),
E = Target.inst_end(); II != E; ++II) {
Record *Inst = (*II)->TheDef;
std::vector<Record*> Uses = Inst->getValueAsListOfDefs("Uses");
if (!Uses.empty()) {
unsigned &IL = EmittedLists[Uses];
if (!IL) PrintDefList(Uses, IL = ++ListNumber, OS);
}
std::vector<Record*> Defs = Inst->getValueAsListOfDefs("Defs");
if (!Defs.empty()) {
unsigned &IL = EmittedLists[Defs];
if (!IL) PrintDefList(Defs, IL = ++ListNumber, OS);
}
}
OperandInfoMapTy OperandInfoIDs;
// Emit all of the operand info records.
EmitOperandInfo(OS, OperandInfoIDs);
// Emit all of the MCInstrDesc records in their ENUM ordering.
//
OS << "\nextern const MCInstrDesc " << TargetName << "Insts[] = {\n";
const std::vector<const CodeGenInstruction*> &NumberedInstructions =
Target.getInstructionsByEnumValue();
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i)
emitRecord(*NumberedInstructions[i], i, InstrInfo, EmittedLists,
OperandInfoIDs, OS);
OS << "};\n\n";
// Build an array of instruction names
SequenceToOffsetTable<std::string> InstrNames;
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
const CodeGenInstruction *Instr = NumberedInstructions[i];
InstrNames.add(Instr->TheDef->getName());
}
InstrNames.layout();
OS << "extern const char " << TargetName << "InstrNameData[] = {\n";
InstrNames.emit(OS, printChar);
OS << "};\n\n";
OS << "extern const unsigned " << TargetName <<"InstrNameIndices[] = {";
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
if (i % 8 == 0)
OS << "\n ";
const CodeGenInstruction *Instr = NumberedInstructions[i];
OS << InstrNames.get(Instr->TheDef->getName()) << "U, ";
}
OS << "\n};\n\n";
// MCInstrInfo initialization routine.
OS << "static inline void Init" << TargetName
<< "MCInstrInfo(MCInstrInfo *II) {\n";
OS << " II->InitMCInstrInfo(" << TargetName << "Insts, "
<< TargetName << "InstrNameIndices, " << TargetName << "InstrNameData, "
<< NumberedInstructions.size() << ");\n}\n\n";
OS << "} // End llvm namespace \n";
OS << "#endif // GET_INSTRINFO_MC_DESC\n\n";
// Create a TargetInstrInfo subclass to hide the MC layer initialization.
OS << "\n#ifdef GET_INSTRINFO_HEADER\n";
OS << "#undef GET_INSTRINFO_HEADER\n";
std::string ClassName = TargetName + "GenInstrInfo";
OS << "namespace llvm {\n";
OS << "struct " << ClassName << " : public TargetInstrInfoImpl {\n"
<< " explicit " << ClassName << "(int SO = -1, int DO = -1);\n"
<< "};\n";
OS << "} // End llvm namespace \n";
OS << "#endif // GET_INSTRINFO_HEADER\n\n";
OS << "\n#ifdef GET_INSTRINFO_CTOR\n";
OS << "#undef GET_INSTRINFO_CTOR\n";
OS << "namespace llvm {\n";
OS << "extern const MCInstrDesc " << TargetName << "Insts[];\n";
OS << "extern const unsigned " << TargetName << "InstrNameIndices[];\n";
OS << "extern const char " << TargetName << "InstrNameData[];\n";
OS << ClassName << "::" << ClassName << "(int SO, int DO)\n"
<< " : TargetInstrInfoImpl(SO, DO) {\n"
<< " InitMCInstrInfo(" << TargetName << "Insts, "
<< TargetName << "InstrNameIndices, " << TargetName << "InstrNameData, "
<< NumberedInstructions.size() << ");\n}\n";
OS << "} // End llvm namespace \n";
OS << "#endif // GET_INSTRINFO_CTOR\n\n";
}
void InstrInfoEmitter::emitRecord(const CodeGenInstruction &Inst, unsigned Num,
Record *InstrInfo,
std::map<std::vector<Record*>, unsigned> &EmittedLists,
const OperandInfoMapTy &OpInfo,
raw_ostream &OS) {
int MinOperands = 0;
if (!Inst.Operands.size() == 0)
// Each logical operand can be multiple MI operands.
MinOperands = Inst.Operands.back().MIOperandNo +
Inst.Operands.back().MINumOperands;
Record *ItinDef = Inst.TheDef->getValueAsDef("Itinerary");
OS << " { ";
OS << Num << ",\t" << MinOperands << ",\t"
<< Inst.Operands.NumDefs << ",\t"
<< SchedModels.getItinClassIdx(ItinDef) << ",\t"
<< Inst.TheDef->getValueAsInt("Size") << ",\t0";
// Emit all of the target indepedent flags...
if (Inst.isPseudo) OS << "|(1<<MCID::Pseudo)";
if (Inst.isReturn) OS << "|(1<<MCID::Return)";
if (Inst.isBranch) OS << "|(1<<MCID::Branch)";
if (Inst.isIndirectBranch) OS << "|(1<<MCID::IndirectBranch)";
if (Inst.isCompare) OS << "|(1<<MCID::Compare)";
if (Inst.isMoveImm) OS << "|(1<<MCID::MoveImm)";
if (Inst.isBitcast) OS << "|(1<<MCID::Bitcast)";
if (Inst.isSelect) OS << "|(1<<MCID::Select)";
if (Inst.isBarrier) OS << "|(1<<MCID::Barrier)";
if (Inst.hasDelaySlot) OS << "|(1<<MCID::DelaySlot)";
if (Inst.isCall) OS << "|(1<<MCID::Call)";
if (Inst.canFoldAsLoad) OS << "|(1<<MCID::FoldableAsLoad)";
if (Inst.mayLoad) OS << "|(1<<MCID::MayLoad)";
if (Inst.mayStore) OS << "|(1<<MCID::MayStore)";
if (Inst.isPredicable) OS << "|(1<<MCID::Predicable)";
if (Inst.isConvertibleToThreeAddress) OS << "|(1<<MCID::ConvertibleTo3Addr)";
if (Inst.isCommutable) OS << "|(1<<MCID::Commutable)";
if (Inst.isTerminator) OS << "|(1<<MCID::Terminator)";
if (Inst.isReMaterializable) OS << "|(1<<MCID::Rematerializable)";
if (Inst.isNotDuplicable) OS << "|(1<<MCID::NotDuplicable)";
if (Inst.Operands.hasOptionalDef) OS << "|(1<<MCID::HasOptionalDef)";
if (Inst.usesCustomInserter) OS << "|(1<<MCID::UsesCustomInserter)";
if (Inst.hasPostISelHook) OS << "|(1<<MCID::HasPostISelHook)";
if (Inst.Operands.isVariadic)OS << "|(1<<MCID::Variadic)";
if (Inst.hasSideEffects) OS << "|(1<<MCID::UnmodeledSideEffects)";
if (Inst.isAsCheapAsAMove) OS << "|(1<<MCID::CheapAsAMove)";
if (Inst.hasExtraSrcRegAllocReq) OS << "|(1<<MCID::ExtraSrcRegAllocReq)";
if (Inst.hasExtraDefRegAllocReq) OS << "|(1<<MCID::ExtraDefRegAllocReq)";
// Emit all of the target-specific flags...
BitsInit *TSF = Inst.TheDef->getValueAsBitsInit("TSFlags");
if (!TSF) throw "no TSFlags?";
uint64_t Value = 0;
for (unsigned i = 0, e = TSF->getNumBits(); i != e; ++i) {
if (BitInit *Bit = dynamic_cast<BitInit*>(TSF->getBit(i)))
Value |= uint64_t(Bit->getValue()) << i;
else
throw "Invalid TSFlags bit in " + Inst.TheDef->getName();
}
OS << ", 0x";
OS.write_hex(Value);
OS << "ULL, ";
// Emit the implicit uses and defs lists...
std::vector<Record*> UseList = Inst.TheDef->getValueAsListOfDefs("Uses");
if (UseList.empty())
OS << "NULL, ";
else
OS << "ImplicitList" << EmittedLists[UseList] << ", ";
std::vector<Record*> DefList = Inst.TheDef->getValueAsListOfDefs("Defs");
if (DefList.empty())
OS << "NULL, ";
else
OS << "ImplicitList" << EmittedLists[DefList] << ", ";
// Emit the operand info.
std::vector<std::string> OperandInfo = GetOperandInfo(Inst);
if (OperandInfo.empty())
OS << "0";
else
OS << "OperandInfo" << OpInfo.find(OperandInfo)->second;
OS << " }, // Inst #" << Num << " = " << Inst.TheDef->getName() << "\n";
}
// emitEnums - Print out enum values for all of the instructions.
void InstrInfoEmitter::emitEnums(raw_ostream &OS) {
OS << "\n#ifdef GET_INSTRINFO_ENUM\n";
OS << "#undef GET_INSTRINFO_ENUM\n";
OS << "namespace llvm {\n\n";
CodeGenTarget Target(Records);
// We must emit the PHI opcode first...
std::string Namespace = Target.getInstNamespace();
if (Namespace.empty()) {
fprintf(stderr, "No instructions defined!\n");
exit(1);
}
const std::vector<const CodeGenInstruction*> &NumberedInstructions =
Target.getInstructionsByEnumValue();
OS << "namespace " << Namespace << " {\n";
OS << " enum {\n";
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
OS << " " << NumberedInstructions[i]->TheDef->getName()
<< "\t= " << i << ",\n";
}
OS << " INSTRUCTION_LIST_END = " << NumberedInstructions.size() << "\n";
OS << " };\n}\n";
OS << "} // End llvm namespace \n";
OS << "#endif // GET_INSTRINFO_ENUM\n\n";
}
namespace llvm {
void EmitInstrInfo(RecordKeeper &RK, raw_ostream &OS) {
InstrInfoEmitter(RK).run(OS);
}
} // End llvm namespace