llvm-6502/utils/TableGen/InstrInfoEmitter.cpp
Alkis Evlogimenos 73ff5120eb Change MRegisterDesc::AliasSet, TargetInstrDescriptor::ImplicitDefs
and TargetInstrDescriptor::ImplicitUses to always point to a null
terminated array and never be null. So there is no need to check for
pointer validity when iterating over those sets. Code that looked
like:

if (const unsigned* AS = TID.ImplicitDefs) {
  for (int i = 0; AS[i]; ++i) {
    // use AS[i]
  }
}

was changed to:

for (const unsigned* AS = TID.ImplicitDefs; *AS; ++AS) {
  // use *AS
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8960 91177308-0d34-0410-b5e6-96231b3b80d8
2003-10-08 05:20:08 +00:00

165 lines
5.8 KiB
C++

//===- InstrInfoEmitter.cpp - Generate a Instruction Set Desc. ------------===//
//
// This tablegen backend is responsible for emitting a description of the target
// instruction set for the code generator.
//
//===----------------------------------------------------------------------===//
#include "InstrInfoEmitter.h"
#include "CodeGenWrappers.h"
#include "Record.h"
// runEnums - Print out enum values for all of the instructions.
void InstrInfoEmitter::runEnums(std::ostream &OS) {
std::vector<Record*> Insts = Records.getAllDerivedDefinitions("Instruction");
if (Insts.size() == 0)
throw std::string("No 'Instruction' subclasses defined!");
std::string Namespace = Insts[0]->getValueAsString("Namespace");
EmitSourceFileHeader("Target Instruction Enum Values", OS);
if (!Namespace.empty())
OS << "namespace " << Namespace << " {\n";
OS << " enum {\n";
CodeGenTarget Target;
// We must emit the PHI opcode first...
Record *InstrInfo = Target.getInstructionSet();
Record *PHI = InstrInfo->getValueAsDef("PHIInst");
OS << " " << PHI->getName() << ", \t// 0 (fixed for all targets)\n";
// Print out the rest of the instructions now...
for (unsigned i = 0, e = Insts.size(); i != e; ++i)
if (Insts[i] != PHI)
OS << " " << Insts[i]->getName() << ", \t// " << i+1 << "\n";
OS << " };\n";
if (!Namespace.empty())
OS << "}\n";
}
void InstrInfoEmitter::printDefList(ListInit *LI, const std::string &Name,
std::ostream &OS) const {
OS << "static const unsigned " << Name << "[] = { ";
for (unsigned j = 0, e = LI->getSize(); j != e; ++j)
if (DefInit *DI = dynamic_cast<DefInit*>(LI->getElement(j)))
OS << getQualifiedName(DI->getDef()) << ", ";
else
throw "Illegal value in '" + Name + "' list!";
OS << "0 };\n";
}
// run - Emit the main instruction description records for the target...
void InstrInfoEmitter::run(std::ostream &OS) {
EmitSourceFileHeader("Target Instruction Descriptors", OS);
CodeGenTarget Target;
const std::string &TargetName = Target.getName();
Record *InstrInfo = Target.getInstructionSet();
Record *PHI = InstrInfo->getValueAsDef("PHIInst");
std::vector<Record*> Instructions =
Records.getAllDerivedDefinitions("Instruction");
// Emit empty implicit uses and defs lists
OS << "static const unsigned EmptyImpUses[] = { 0 };\n"
<< "static const unsigned EmptyImpDefs[] = { 0 };\n";
// Emit all of the instruction's implicit uses and defs...
for (unsigned i = 0, e = Instructions.size(); i != e; ++i) {
Record *Inst = Instructions[i];
ListInit *LI = Inst->getValueAsListInit("Uses");
if (LI->getSize()) printDefList(LI, Inst->getName()+"ImpUses", OS);
LI = Inst->getValueAsListInit("Defs");
if (LI->getSize()) printDefList(LI, Inst->getName()+"ImpDefs", OS);
}
OS << "\nstatic const TargetInstrDescriptor " << TargetName
<< "Insts[] = {\n";
emitRecord(PHI, 0, InstrInfo, OS);
for (unsigned i = 0, e = Instructions.size(); i != e; ++i)
if (Instructions[i] != PHI)
emitRecord(Instructions[i], i+1, InstrInfo, OS);
OS << "};\n";
}
void InstrInfoEmitter::emitRecord(Record *R, unsigned Num, Record *InstrInfo,
std::ostream &OS) {
OS << " { \"" << R->getValueAsString("Name")
<< "\",\t-1, -1, 0, false, 0, 0, 0, 0";
// Emit all of the target indepedent flags...
if (R->getValueAsBit("isReturn")) OS << "|M_RET_FLAG";
if (R->getValueAsBit("isBranch")) OS << "|M_BRANCH_FLAG";
if (R->getValueAsBit("isCall" )) OS << "|M_CALL_FLAG";
if (R->getValueAsBit("isTwoAddress")) OS << "|M_2_ADDR_FLAG";
if (R->getValueAsBit("isTerminator")) OS << "|M_TERMINATOR_FLAG";
OS << ", 0";
// Emit all of the target-specific flags...
ListInit *LI = InstrInfo->getValueAsListInit("TSFlagsFields");
ListInit *Shift = InstrInfo->getValueAsListInit("TSFlagsShifts");
if (LI->getSize() != Shift->getSize())
throw "Lengths of " + InstrInfo->getName() +
":(TargetInfoFields, TargetInfoPositions) must be equal!";
for (unsigned i = 0, e = LI->getSize(); i != e; ++i)
emitShiftedValue(R, dynamic_cast<StringInit*>(LI->getElement(i)),
dynamic_cast<IntInit*>(Shift->getElement(i)), OS);
OS << ", ";
// Emit the implicit uses and defs lists...
LI = R->getValueAsListInit("Uses");
if (!LI->getSize())
OS << "EmptyImpUses, ";
else
OS << R->getName() << "ImpUses, ";
LI = R->getValueAsListInit("Defs");
if (!LI->getSize())
OS << "EmptyImpDefs ";
else
OS << R->getName() << "ImpDefs ";
OS << " }, // Inst #" << Num << " = " << R->getName() << "\n";
}
void InstrInfoEmitter::emitShiftedValue(Record *R, StringInit *Val,
IntInit *ShiftInt, std::ostream &OS) {
if (Val == 0 || ShiftInt == 0)
throw std::string("Illegal value or shift amount in TargetInfo*!");
RecordVal *RV = R->getValue(Val->getValue());
int Shift = ShiftInt->getValue();
if (RV == 0 || RV->getValue() == 0)
throw R->getName() + " doesn't have a field named '" + Val->getValue()+"'!";
Init *Value = RV->getValue();
if (BitInit *BI = dynamic_cast<BitInit*>(Value)) {
if (BI->getValue()) OS << "|(1<<" << Shift << ")";
return;
} else if (BitsInit *BI = dynamic_cast<BitsInit*>(Value)) {
// Convert the Bits to an integer to print...
Init *I = BI->convertInitializerTo(new IntRecTy());
if (I)
if (IntInit *II = dynamic_cast<IntInit*>(I)) {
if (II->getValue())
OS << "|(" << II->getValue() << "<<" << Shift << ")";
return;
}
} else if (IntInit *II = dynamic_cast<IntInit*>(Value)) {
if (II->getValue()) OS << "|(" << II->getValue() << "<<" << Shift << ")";
return;
}
std::cerr << "Unhandled initializer: " << *Val << "\n";
throw "In record '" + R->getName() + "' for TSFlag emission.";
}