diff options
Diffstat (limited to 'lib/Bytecode/Writer/Writer.cpp')
-rw-r--r-- | lib/Bytecode/Writer/Writer.cpp | 809 |
1 files changed, 762 insertions, 47 deletions
diff --git a/lib/Bytecode/Writer/Writer.cpp b/lib/Bytecode/Writer/Writer.cpp index 395386d662..9bc5ce600a 100644 --- a/lib/Bytecode/Writer/Writer.cpp +++ b/lib/Bytecode/Writer/Writer.cpp @@ -10,24 +10,21 @@ // This library implements the functionality defined in llvm/Bytecode/Writer.h // // Note that this file uses an unusual technique of outputting all the bytecode -// to a deque of unsigned char, then copies the deque to an ostream. The +// to a vector of unsigned char, then copies the vector to an ostream. The // reason for this is that we must do "seeking" in the stream to do back- // patching, and some very important ostreams that we want to support (like // pipes) do not support seeking. :( :( :( // -// The choice of the deque data structure is influenced by the extremely fast -// "append" speed, plus the free "seek"/replace in the middle of the stream. I -// didn't use a vector because the stream could end up very large and copying -// the whole thing to reallocate would be kinda silly. -// //===----------------------------------------------------------------------===// #include "WriterInternals.h" #include "llvm/Bytecode/WriteBytecodePass.h" #include "llvm/Constants.h" #include "llvm/DerivedTypes.h" +#include "llvm/Instructions.h" #include "llvm/Module.h" #include "llvm/SymbolTable.h" +#include "llvm/Support/GetElementPtrTypeIterator.h" #include "Support/STLExtras.h" #include "Support/Statistic.h" #include <cstring> @@ -39,15 +36,720 @@ static RegisterPass<WriteBytecodePass> X("emitbytecode", "Bytecode Writer"); static Statistic<> BytesWritten("bytecodewriter", "Number of bytecode bytes written"); -BytecodeWriter::BytecodeWriter(std::deque<unsigned char> &o, const Module *M) +//===----------------------------------------------------------------------===// +//=== Output Primitives ===// +//===----------------------------------------------------------------------===// + +// output - If a position is specified, it must be in the valid portion of the +// string... note that this should be inlined always so only the relevant IF +// body should be included. +inline void BytecodeWriter::output(unsigned i, int pos) { + if (pos == -1) { // Be endian clean, little endian is our friend + Out.push_back((unsigned char)i); + Out.push_back((unsigned char)(i >> 8)); + Out.push_back((unsigned char)(i >> 16)); + Out.push_back((unsigned char)(i >> 24)); + } else { + Out[pos ] = (unsigned char)i; + Out[pos+1] = (unsigned char)(i >> 8); + Out[pos+2] = (unsigned char)(i >> 16); + Out[pos+3] = (unsigned char)(i >> 24); + } +} + +inline void BytecodeWriter::output(int i) { + output((unsigned)i); +} + +/// output_vbr - Output an unsigned value, by using the least number of bytes +/// possible. This is useful because many of our "infinite" values are really +/// very small most of the time; but can be large a few times. +/// Data format used: If you read a byte with the high bit set, use the low +/// seven bits as data and then read another byte. Note that using this may +/// cause the output buffer to become unaligned. +inline void BytecodeWriter::output_vbr(uint64_t i) { + while (1) { + if (i < 0x80) { // done? + Out.push_back((unsigned char)i); // We know the high bit is clear... + return; + } + + // Nope, we are bigger than a character, output the next 7 bits and set the + // high bit to say that there is more coming... + Out.push_back(0x80 | ((unsigned char)i & 0x7F)); + i >>= 7; // Shift out 7 bits now... + } +} + +inline void BytecodeWriter::output_vbr(unsigned i) { + while (1) { + if (i < 0x80) { // done? + Out.push_back((unsigned char)i); // We know the high bit is clear... + return; + } + + // Nope, we are bigger than a character, output the next 7 bits and set the + // high bit to say that there is more coming... + Out.push_back(0x80 | ((unsigned char)i & 0x7F)); + i >>= 7; // Shift out 7 bits now... + } +} + +inline void BytecodeWriter::output_typeid(unsigned i) { + if (i <= 0x00FFFFFF) + this->output_vbr(i); + else { + this->output_vbr(0x00FFFFFF); + this->output_vbr(i); + } +} + +inline void BytecodeWriter::output_vbr(int64_t i) { + if (i < 0) + output_vbr(((uint64_t)(-i) << 1) | 1); // Set low order sign bit... + else + output_vbr((uint64_t)i << 1); // Low order bit is clear. +} + + +inline void BytecodeWriter::output_vbr(int i) { + if (i < 0) + output_vbr(((unsigned)(-i) << 1) | 1); // Set low order sign bit... + else + output_vbr((unsigned)i << 1); // Low order bit is clear. +} + +// align32 - emit the minimal number of bytes that will bring us to 32 bit +// alignment... +// +inline void BytecodeWriter::align32() { + int NumPads = (4-(Out.size() & 3)) & 3; // Bytes to get padding to 32 bits + while (NumPads--) Out.push_back((unsigned char)0xAB); +} + +inline void BytecodeWriter::output(const std::string &s, bool Aligned ) { + unsigned Len = s.length(); + output_vbr(Len ); // Strings may have an arbitrary length... + Out.insert(Out.end(), s.begin(), s.end()); + + if (Aligned) + align32(); // Make sure we are now aligned... +} + +inline void BytecodeWriter::output_data(const void *Ptr, const void *End) { + Out.insert(Out.end(), (const unsigned char*)Ptr, (const unsigned char*)End); +} + +inline void BytecodeWriter::output_float(float& FloatVal) { + /// FIXME: This isn't optimal, it has size problems on some platforms + /// where FP is not IEEE. + union { + float f; + uint32_t i; + } FloatUnion; + FloatUnion.f = FloatVal; + Out.push_back( static_cast<unsigned char>( (FloatUnion.i & 0xFF ))); + Out.push_back( static_cast<unsigned char>( (FloatUnion.i >> 8) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (FloatUnion.i >> 16) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (FloatUnion.i >> 24) & 0xFF)); +} + +inline void BytecodeWriter::output_double(double& DoubleVal) { + /// FIXME: This isn't optimal, it has size problems on some platforms + /// where FP is not IEEE. + union { + double d; + uint64_t i; + } DoubleUnion; + DoubleUnion.d = DoubleVal; + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i & 0xFF ))); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 8) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 16) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 24) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 32) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 40) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 48) & 0xFF)); + Out.push_back( static_cast<unsigned char>( (DoubleUnion.i >> 56) & 0xFF)); +} + +inline BytecodeBlock::BytecodeBlock(unsigned ID, BytecodeWriter& w, + bool elideIfEmpty, bool hasLongFormat ) + : Id(ID), Writer(w), ElideIfEmpty(elideIfEmpty), HasLongFormat(hasLongFormat){ + + if (HasLongFormat) { + w.output(ID); + w.output(0U); // For length in long format + } else { + w.output(0U); /// Place holder for ID and length for this block + } + Loc = w.size(); +} + +inline BytecodeBlock::~BytecodeBlock() { // Do backpatch when block goes out + // of scope... + if (Loc == Writer.size() && ElideIfEmpty) { + // If the block is empty, and we are allowed to, do not emit the block at + // all! + Writer.resize(Writer.size()-(HasLongFormat?8:4)); + return; + } + + //cerr << "OldLoc = " << Loc << " NewLoc = " << NewLoc << " diff = " + // << (NewLoc-Loc) << endl; + if (HasLongFormat) + Writer.output(unsigned(Writer.size()-Loc), int(Loc-4)); + else + Writer.output(unsigned(Writer.size()-Loc) << 5 | (Id & 0x1F), int(Loc-4)); + Writer.align32(); // Blocks must ALWAYS be aligned +} + +//===----------------------------------------------------------------------===// +//=== Constant Output ===// +//===----------------------------------------------------------------------===// + +void BytecodeWriter::outputType(const Type *T) { + output_vbr((unsigned)T->getTypeID()); + + // That's all there is to handling primitive types... + if (T->isPrimitiveType()) { + return; // We might do this if we alias a prim type: %x = type int + } + + switch (T->getTypeID()) { // Handle derived types now. + case Type::FunctionTyID: { + const FunctionType *MT = cast<FunctionType>(T); + int Slot = Table.getSlot(MT->getReturnType()); + assert(Slot != -1 && "Type used but not available!!"); + output_typeid((unsigned)Slot); + + // Output the number of arguments to function (+1 if varargs): + output_vbr((unsigned)MT->getNumParams()+MT->isVarArg()); + + // Output all of the arguments... + FunctionType::param_iterator I = MT->param_begin(); + for (; I != MT->param_end(); ++I) { + Slot = Table.getSlot(*I); + assert(Slot != -1 && "Type used but not available!!"); + output_typeid((unsigned)Slot); + } + + // Terminate list with VoidTy if we are a varargs function... + if (MT->isVarArg()) + output_typeid((unsigned)Type::VoidTyID); + break; + } + + case Type::ArrayTyID: { + const ArrayType *AT = cast<ArrayType>(T); + int Slot = Table.getSlot(AT->getElementType()); + assert(Slot != -1 && "Type used but not available!!"); + output_typeid((unsigned)Slot); + //std::cerr << "Type slot = " << Slot << " Type = " << T->getName() << endl; + + output_vbr(AT->getNumElements()); + break; + } + + case Type::StructTyID: { + const StructType *ST = cast<StructType>(T); + + // Output all of the element types... + for (StructType::element_iterator I = ST->element_begin(), + E = ST->element_end(); I != E; ++I) { + int Slot = Table.getSlot(*I); + assert(Slot != -1 && "Type used but not available!!"); + output_typeid((unsigned)Slot); + } + + // Terminate list with VoidTy + output_typeid((unsigned)Type::VoidTyID); + break; + } + + case Type::PointerTyID: { + const PointerType *PT = cast<PointerType>(T); + int Slot = Table.getSlot(PT->getElementType()); + assert(Slot != -1 && "Type used but not available!!"); + output_typeid((unsigned)Slot); + break; + } + + case Type::OpaqueTyID: { + // No need to emit anything, just the count of opaque types is enough. + break; + } + + //case Type::PackedTyID: + default: + std::cerr << __FILE__ << ":" << __LINE__ << ": Don't know how to serialize" + << " Type '" << T->getDescription() << "'\n"; + break; + } +} + +void BytecodeWriter::outputConstant(const Constant *CPV) { + assert((CPV->getType()->isPrimitiveType() || !CPV->isNullValue()) && + "Shouldn't output null constants!"); + + // We must check for a ConstantExpr before switching by type because + // a ConstantExpr can be of any type, and has no explicit value. + // + if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CPV)) { + // FIXME: Encoding of constant exprs could be much more compact! + assert(CE->getNumOperands() > 0 && "ConstantExpr with 0 operands"); + output_vbr(CE->getNumOperands()); // flags as an expr + output_vbr(CE->getOpcode()); // flags as an expr + + for (User::const_op_iterator OI = CE->op_begin(); OI != CE->op_end(); ++OI){ + int Slot = Table.getSlot(*OI); + assert(Slot != -1 && "Unknown constant used in ConstantExpr!!"); + output_vbr((unsigned)Slot); + Slot = Table.getSlot((*OI)->getType()); + output_typeid((unsigned)Slot); + } + return; + } else { + output_vbr(0U); // flag as not a ConstantExpr + } + + switch (CPV->getType()->getTypeID()) { + case Type::BoolTyID: // Boolean Types + if (cast<ConstantBool>(CPV)->getValue()) + output_vbr(1U); + else + output_vbr(0U); + break; + + case Type::UByteTyID: // Unsigned integer types... + case Type::UShortTyID: + case Type::UIntTyID: + case Type::ULongTyID: + output_vbr(cast<ConstantUInt>(CPV)->getValue()); + break; + + case Type::SByteTyID: // Signed integer types... + case Type::ShortTyID: + case Type::IntTyID: + case Type::LongTyID: + output_vbr(cast<ConstantSInt>(CPV)->getValue()); + break; + + case Type::ArrayTyID: { + const ConstantArray *CPA = cast<ConstantArray>(CPV); + assert(!CPA->isString() && "Constant strings should be handled specially!"); + + for (unsigned i = 0; i != CPA->getNumOperands(); ++i) { + int Slot = Table.getSlot(CPA->getOperand(i)); + assert(Slot != -1 && "Constant used but not available!!"); + output_vbr((unsigned)Slot); + } + break; + } + + case Type::StructTyID: { + const ConstantStruct *CPS = cast<ConstantStruct>(CPV); + const std::vector<Use> &Vals = CPS->getValues(); + + for (unsigned i = 0; i < Vals.size(); ++i) { + int Slot = Table.getSlot(Vals[i]); + assert(Slot != -1 && "Constant used but not available!!"); + output_vbr((unsigned)Slot); + } + break; + } + + case Type::PointerTyID: + assert(0 && "No non-null, non-constant-expr constants allowed!"); + abort(); + + case Type::FloatTyID: { // Floating point types... + float Tmp = (float)cast<ConstantFP>(CPV)->getValue(); + output_float(Tmp); + break; + } + case Type::DoubleTyID: { + double Tmp = cast<ConstantFP>(CPV)->getValue(); + output_double(Tmp); + break; + } + + case Type::VoidTyID: + case Type::LabelTyID: + default: + std::cerr << __FILE__ << ":" << __LINE__ << ": Don't know how to serialize" + << " type '" << *CPV->getType() << "'\n"; + break; + } + return; +} + +void BytecodeWriter::outputConstantStrings() { + SlotCalculator::string_iterator I = Table.string_begin(); + SlotCalculator::string_iterator E = Table.string_end(); + if (I == E) return; // No strings to emit + + // If we have != 0 strings to emit, output them now. Strings are emitted into + // the 'void' type plane. + output_vbr(unsigned(E-I)); + output_typeid(Type::VoidTyID); + + // Emit all of the strings. + for (I = Table.string_begin(); I != E; ++I) { + const ConstantArray *Str = *I; + int Slot = Table.getSlot(Str->getType()); + assert(Slot != -1 && "Constant string of unknown type?"); + output_typeid((unsigned)Slot); + + // Now that we emitted the type (which indicates the size of the string), + // emit all of the characters. + std::string Val = Str->getAsString(); + output_data(Val.c_str(), Val.c_str()+Val.size()); + } +} + +//===----------------------------------------------------------------------===// +//=== Instruction Output ===// +//===----------------------------------------------------------------------===// +typedef unsigned char uchar; + +// outputInstructionFormat0 - Output those wierd instructions that have a large +// number of operands or have large operands themselves... +// +// Format: [opcode] [type] [numargs] [arg0] [arg1] ... [arg<numargs-1>] +// +void BytecodeWriter::outputInstructionFormat0(const Instruction *I, unsigned Opcode, + const SlotCalculator &Table, + unsigned Type) { + // Opcode must have top two bits clear... + output_vbr(Opcode << 2); // Instruction Opcode ID + output_typeid(Type); // Result type + + unsigned NumArgs = I->getNumOperands(); + output_vbr(NumArgs + (isa<CastInst>(I) || isa<VANextInst>(I) || + isa<VAArgInst>(I))); + + if (!isa<GetElementPtrInst>(&I)) { + for (unsigned i = 0; i < NumArgs; ++i) { + int Slot = Table.getSlot(I->getOperand(i)); + assert(Slot >= 0 && "No slot number for value!?!?"); + output_vbr((unsigned)Slot); + } + + if (isa<CastInst>(I) || isa<VAArgInst>(I)) { + int Slot = Table.getSlot(I->getType()); + assert(Slot != -1 && "Cast return type unknown?"); + output_typeid((unsigned)Slot); + } else if (const VANextInst *VAI = dyn_cast<VANextInst>(I)) { + int Slot = Table.getSlot(VAI->getArgType()); + assert(Slot != -1 && "VarArg argument type unknown?"); + output_typeid((unsigned)Slot); + } + + } else { + int Slot = Table.getSlot(I->getOperand(0)); + assert(Slot >= 0 && "No slot number for value!?!?"); + output_vbr(unsigned(Slot)); + + // We need to encode the type of sequential type indices into their slot # + unsigned Idx = 1; + for (gep_type_iterator TI = gep_type_begin(I), E = gep_type_end(I); + Idx != NumArgs; ++TI, ++Idx) { + Slot = Table.getSlot(I->getOperand(Idx)); + assert(Slot >= 0 && "No slot number for value!?!?"); + + if (isa<SequentialType>(*TI)) { + unsigned IdxId; + switch (I->getOperand(Idx)->getType()->getTypeID()) { + default: assert(0 && "Unknown index type!"); + case Type::UIntTyID: IdxId = 0; break; + case Type::IntTyID: IdxId = 1; break; + case Type::ULongTyID: IdxId = 2; break; + case Type::LongTyID: IdxId = 3; break; + } + Slot = (Slot << 2) | IdxId; + } + output_vbr(unsigned(Slot)); + } + } + + align32(); // We must maintain correct alignment! +} + + +// outputInstrVarArgsCall - Output the absurdly annoying varargs function calls. +// This are more annoying than most because the signature of the call does not +// tell us anything about the types of the arguments in the varargs portion. +// Because of this, we encode (as type 0) all of the argument types explicitly +// before the argument value. This really sucks, but you shouldn't be using +// varargs functions in your code! *death to printf*! +// +// Format: [opcode] [type] [numargs] [arg0] [arg1] ... [arg<numargs-1>] +// +void BytecodeWriter::outputInstrVarArgsCall(const Instruction *I, + unsigned Opcode, + const SlotCalculator &Table, + unsigned Type) { + assert(isa<CallInst>(I) || isa<InvokeInst>(I)); + // Opcode must have top two bits clear... + output_vbr(Opcode << 2); // Instruction Opcode ID + output_typeid(Type); // Result type (varargs type) + + const PointerType *PTy = cast<PointerType>(I->getOperand(0)->getType()); + const FunctionType *FTy = cast<FunctionType>(PTy->getElementType()); + unsigned NumParams = FTy->getNumParams(); + + unsigned NumFixedOperands; + if (isa<CallInst>(I)) { + // Output an operand for the callee and each fixed argument, then two for + // each variable argument. + NumFixedOperands = 1+NumParams; + } else { + assert(isa<InvokeInst>(I) && "Not call or invoke??"); + // Output an operand for the callee and destinations, then two for each + // variable argument. + NumFixedOperands = 3+NumParams; + } + output_vbr(2 * I->getNumOperands()-NumFixedOperands); + + // The type for the function has already been emitted in the type field of the + // instruction. Just emit the slot # now. + for (unsigned i = 0; i != NumFixedOperands; ++i) { + int Slot = Table.getSlot(I->getOperand(i)); + assert(Slot >= 0 && "No slot number for value!?!?"); + output_vbr((unsigned)Slot); + } + + for (unsigned i = NumFixedOperands, e = I->getNumOperands(); i != e; ++i) { + // Output Arg Type ID + int Slot = Table.getSlot(I->getOperand(i)->getType()); + assert(Slot >= 0 && "No slot number for value!?!?"); + output_typeid((unsigned)Slot); + + // Output arg ID itself + Slot = Table.getSlot(I->getOperand(i)); + assert(Slot >= 0 && "No slot number for value!?!?"); + output_vbr((unsigned)Slot); + } + align32(); // We must maintain correct alignment! +} + + +// outputInstructionFormat1 - Output one operand instructions, knowing that no +// operand index is >= 2^12. +// +inline void BytecodeWriter::outputInstructionFormat1(const Instruction *I, + unsigned Opcode, + unsigned *Slots, + unsigned Type) { + // bits Instruction format: + // -------------------------- + // 01-00: Opcode type, fixed to 1. + // 07-02: Opcode + // 19-08: Resulting type plane + // 31-20: Operand #1 (if set to (2^12-1), then zero operands) + // + unsigned Bits = 1 | (Opcode << 2) | (Type << 8) | (Slots[0] << 20); + // cerr << "1 " << IType << " " << Type << " " << Slots[0] << endl; + output(Bits); +} + + +// outputInstructionFormat2 - Output two operand instructions, knowing that no +// operand index is >= 2^8. +// +inline void BytecodeWriter::outputInstructionFormat2(const Instruction *I, + unsigned Opcode, + unsigned *Slots, + unsigned Type) { + // bits Instruction format: + // -------------------------- + // 01-00: Opcode type, fixed to 2. + // 07-02: Opcode + // 15-08: Resulting type plane + // 23-16: Operand #1 + // 31-24: Operand #2 + // + unsigned Bits = 2 | (Opcode << 2) | (Type << 8) | + (Slots[0] << 16) | (Slots[1] << 24); + // cerr << "2 " << IType << " " << Type << " " << Slots[0] << " " + // << Slots[1] << endl; + output(Bits); +} + + +// outputInstructionFormat3 - Output three operand instructions, knowing that no +// operand index is >= 2^6. +// +inline void BytecodeWriter::outputInstructionFormat3(const Instruction *I, + unsigned Opcode, + unsigned *Slots, + unsigned Type) { + // bits Instruction format: + // -------------------------- + // 01-00: Opcode type, fixed to 3. + // 07-02: Opcode + // 13-08: Resulting type plane + // 19-14: Operand #1 + // 25-20: Operand #2 + // 31-26: Operand #3 + // + unsigned Bits = 3 | (Opcode << 2) | (Type << 8) | + (Slots[0] << 14) | (Slots[1] << 20) | (Slots[2] << 26); + //cerr << "3 " << IType << " " << Type << " " << Slots[0] << " " + // << Slots[1] << " " << Slots[2] << endl; + output(Bits); +} + +void BytecodeWriter::outputInstruction(const Instruction &I) { + assert(I.getOpcode() < 62 && "Opcode too big???"); + unsigned Opcode = I.getOpcode(); + unsigned NumOperands = I.getNumOperands(); + + // Encode 'volatile load' as 62 and 'volatile store' as 63. + if (isa<LoadInst>(I) && cast<LoadInst>(I).isVolatile()) + Opcode = 62; + if (isa<StoreInst>(I) && cast<StoreInst>(I).isVolatile()) + Opcode = 63; + + // Figure out which type to encode with the instruction. Typically we want + // the type of the first parameter, as opposed to the type of the instruction + // (for example, with setcc, we always know it returns bool, but the type of + // the first param is actually interesting). But if we have no arguments + // we take the type of the instruction itself. + // + const Type *Ty; + switch (I.getOpcode()) { + case Instruction::Select: + case Instruction::Malloc: + case Instruction::Alloca: + Ty = I.getType(); // These ALWAYS want to encode the return type + break; + case Instruction::Store: + Ty = I.getOperand(1)->getType(); // Encode the pointer type... + assert(isa<PointerType>(Ty) && "Store to nonpointer type!?!?"); + break; + default: // Otherwise use the default behavior... + Ty = NumOperands ? I.getOperand(0)->getType() : I.getType(); + break; + } + + unsigned Type; + int Slot = Table.getSlot(Ty); + assert(Slot != -1 && "Type not available!!?!"); + Type = (unsigned)Slot; + + // Varargs calls and invokes are encoded entirely different from any other + // instructions. + if (const CallInst *CI = dyn_cast<CallInst>(&I)){ + const PointerType *Ty =cast<PointerType>(CI->getCalledValue()->getType()); + if (cast<FunctionType>(Ty->getElementType())->isVarArg()) { + outputInstrVarArgsCall(CI, Opcode, Table, Type); + return; + } + } else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I)) { + const PointerType *Ty =cast<PointerType>(II->getCalledValue()->getType()); + if (cast<FunctionType>(Ty->getElementType())->isVarArg()) { + outputInstrVarArgsCall(II, Opcode, Table, Type); + return; + } + } + + if (NumOperands <= 3) { + // Make sure that we take the type number into consideration. We don't want + // to overflow the field size for the instruction format we select. + // + unsigned MaxOpSlot = Type; + unsigned Slots[3]; Slots[0] = (1 << 12)-1; // Marker to signify 0 operands + + for (unsigned i = 0; i != NumOperands; ++i) { + int slot = Table.getSlot(I.getOperand(i)); + assert(slot != -1 && "Broken bytecode!"); + if (unsigned(slot) > MaxOpSlot) MaxOpSlot = unsigned(slot); + Slots[i] = unsigned(slot); + } + + // Handle the special cases for various instructions... + if (isa<CastInst>(I) || isa<VAArgInst>(I)) { + // Cast has to encode the destination type as the second argument in the + // packet, or else we won't know what type to cast to! + Slots[1] = Table.getSlot(I.getType()); + assert(Slots[1] != ~0U && "Cast return type unknown?"); + if (Slots[1] > MaxOpSlot) MaxOpSlot = Slots[1]; + NumOperands++; + } else if (const VANextInst *VANI = dyn_cast<VANextInst>(&I)) { + Slots[1] = Table.getSlot(VANI->getArgType()); + assert(Slots[1] != ~0U && "va_next return type unknown?"); + if (Slots[1] > MaxOpSlot) MaxOpSlot = Slots[1]; + NumOperands++; + } else if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) { + // We need to encode the type of sequential type indices into their slot # + unsigned Idx = 1; + for (gep_type_iterator I = gep_type_begin(GEP), E = gep_type_end(GEP); + I != E; ++I, ++Idx) + if (isa<SequentialType>(*I)) { + unsigned IdxId; + switch (GEP->getOperand(Idx)->getType()->getTypeID()) { + default: assert(0 && "Unknown index type!"); + case Type::UIntTyID: IdxId = 0; break; + case Type::IntTyID: IdxId = 1; break; + case Type::ULongTyID: IdxId = 2; break; + case Type::LongTyID: IdxId = 3; break; + } + Slots[Idx] = (Slots[Idx] << 2) | IdxId; + if (Slots[Idx] > MaxOpSlot) MaxOpSlot = Slots[Idx]; + } + } + + // Decide which instruction encoding to use. This is determined primarily + // by the number of operands, and secondarily by whether or not the max + // operand will fit into the instruction encoding. More operands == fewer + // bits per operand. + // + switch (NumOperands) { + case 0: + case 1: + if (MaxOpSlot < (1 << 12)-1) { // -1 because we use 4095 to indicate 0 ops + outputInstructionFormat1(&I, Opcode, Slots, Type); + return; + } + break; + + case 2: + if (MaxOpSlot < (1 << 8)) { + outputInstructionFormat2(&I, Opcode, Slots, Type); + return; + } + break; + + case 3: + if (MaxOpSlot < (1 << 6)) { + outputInstructionFormat3(&I, Opcode, Slots, Type); + return; + } + break; + default: + break; + } + } + + // If we weren't handled before here, we either have a large number of + // operands or a large operand index that we are referring to. + outputInstructionFormat0(&I, Opcode, Table, Type); +} + +//===----------------------------------------------------------------------===// +//=== Block Output ===// +//===----------------------------------------------------------------------===// + +BytecodeWriter::BytecodeWriter(std::vector<unsigned char> &o, const Module *M) : Out(o), Table(M) { // Emit the signature... static const unsigned char *Sig = (const unsigned char*)"llvm"; - output_data(Sig, Sig+4, Out); + output_data(Sig, Sig+4); // Emit the top level CLASS block. - BytecodeBlock ModuleBlock(BytecodeFormat::Module, Out); + BytecodeBlock ModuleBlock(BytecodeFormat::ModuleBlockID, *this, false, true); bool isBigEndian = M->getEndianness() == Module::BigEndian; bool hasLongPointers = M->getPointerSize() == Module::Pointer64; @@ -56,14 +758,14 @@ BytecodeWriter::BytecodeWriter(std::deque<unsigned char> &o, const Module *M) // Output the version identifier... we are currently on bytecode version #2, // which corresponds to LLVM v1.3. - unsigned Version = (2 << 4) | (unsigned)isBigEndian | (hasLongPointers << 1) | + unsigned Version = (3 << 4) | (unsigned)isBigEndian | (hasLongPointers << 1) | (hasNoEndianness << 2) | (hasNoPointerSize << 3); - output_vbr(Version, Out); - align32(Out); + output_vbr(Version); + align32(); // The Global type plane comes first { - BytecodeBlock CPool(BytecodeFormat::GlobalTypePlane, Out ); + BytecodeBlock CPool(BytecodeFormat::GlobalTypePlaneBlockID, *this ); outputTypes(Type::FirstDerivedTyID); } @@ -94,7 +796,7 @@ void BytecodeWriter::outputTypes(unsigned TypeNum) unsigned NumEntries = Types.size() - TypeNum; // Output type header: [num entries] - output_vbr(NumEntries, Out); + output_vbr(NumEntries); for (unsigned i = TypeNum; i < TypeNum+NumEntries; ++i) outputType(Types[i]); @@ -126,12 +828,12 @@ void BytecodeWriter::outputConstantsInPlane(const std::vector<const Value*> // Output type header: [num entries][type id number] // - output_vbr(NC, Out); + output_vbr(NC); // Output the Type ID Number... int Slot = Table.getSlot(Plane.front()->getType()); assert (Slot != -1 && "Type in constant pool but not in function!!"); - output_vbr((unsigned)Slot, Out); + output_typeid((unsigned)Slot); for (unsigned i = ValNo; i < ValNo+NC; ++i) { const Value *V = Plane[i]; @@ -146,7 +848,7 @@ static inline bool hasNullValue(unsigned TyID) { } void BytecodeWriter::outputConstants(bool isFunction) { - BytecodeBlock CPool(BytecodeFormat::ConstantPool, Out, + BytecodeBlock CPool(BytecodeFormat::ConstantPoolBlockID, *this, true /* Elide block if empty */); unsigned NumPlanes = Table.getNumPlanes(); @@ -189,7 +891,7 @@ static unsigned getEncodedLinkage(const GlobalValue *GV) { } void BytecodeWriter::outputModuleInfoBlock(const Module *M) { - BytecodeBlock ModuleInfoBlock(BytecodeFormat::ModuleGlobalInfo, Out); + BytecodeBlock ModuleInfoBlock(BytecodeFormat::ModuleGlobalInfoBlockID, *this); // Output the types for the global variables in the module... for (Module::const_giterator I = M->gbegin(), End = M->gend(); I != End;++I) { @@ -200,37 +902,48 @@ void BytecodeWriter::outputModuleInfoBlock(const Module *M) { // bit5+ = Slot # for type unsigned oSlot = ((unsigned)Slot << 5) | (getEncodedLinkage(I) << 2) | (I->hasInitializer() << 1) | (unsigned)I->isConstant(); - output_vbr(oSlot, Out); + output_vbr(oSlot ); // If we have an initializer, output it now. if (I->hasInitializer()) { Slot = Table.getSlot((Value*)I->getInitializer()); assert(Slot != -1 && "No slot for global var initializer!"); - output_vbr((unsigned)Slot, Out); + output_vbr((unsigned)Slot); } } - output_vbr((unsigned)Table.getSlot(Type::VoidTy), Out); + output_typeid((unsigned)Table.getSlot(Type::VoidTy)); // Output the types of the functions in this module... for (Module::const_iterator I = M->begin(), End = M->end(); I != End; ++I) { int Slot = Table.getSlot(I->getType()); assert(Slot != -1 && "Module const pool is broken!"); assert(Slot >= Type::FirstDerivedTyID && "Derived type not in range!"); - output_vbr((unsigned)Slot, Out); + output_typeid((unsigned)Slot); } - output_vbr((unsigned)Table.getSlot(Type::VoidTy), Out); + output_typeid((unsigned)Table.getSlot(Type::VoidTy)); + + // Put out the list of dependent libraries for the Module + Module::const_literator LI = M->lbegin(); + Module::const_literator LE = M->lend(); + output_vbr( unsigned(LE - LI) ); // Put out the number of dependent libraries + for ( ; LI != LE; ++LI ) { + output(*LI, /*aligned=*/false); + } + + // Output the target triple from the module + output(M->getTargetTriple(), /*aligned=*/ true); } void BytecodeWriter::outputInstructions(const Function *F) { - BytecodeBlock ILBlock(BytecodeFormat::InstructionList, Out); + BytecodeBlock ILBlock(BytecodeFormat::InstructionListBlockID, *this); for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB) for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) outputInstruction(*I); } void BytecodeWriter::outputFunction(const Function *F) { - BytecodeBlock FunctionBlock(BytecodeFormat::Function, Out); - output_vbr(getEncodedLinkage(F), Out); + BytecodeBlock FunctionBlock(BytecodeFormat::FunctionBlockID, *this); + output_vbr(getEncodedLinkage(F)); // If this is an external function, there is nothing else to emit! if (F->isExternal()) return; @@ -273,17 +986,17 @@ void BytecodeWriter::outputCompactionTablePlane(unsigned PlaneNo, case 0: // Avoid emitting two vbr's if possible. case 1: case 2: - output_vbr((PlaneNo << 2) | End-StartNo, Out); + output_vbr((PlaneNo << 2) | End-StartNo); break; default: // Output the number of things. - output_vbr((unsigned(End-StartNo) << 2) | 3, Out); - output_vbr(PlaneNo, Out); // Emit the type plane this is + output_vbr((unsigned(End-StartNo) << 2) | 3); + output_typeid(PlaneNo); // Emit the type plane this is break; } for (unsigned i = StartNo; i != End; ++i) - output_vbr(Table.getGlobalSlot(Plane[i]), Out); + output_vbr(Table.getGlobalSlot(Plane[i])); } void BytecodeWriter::outputCompactionTypes(unsigned StartNo) { @@ -293,7 +1006,7 @@ void BytecodeWriter::outputCompactionTypes(unsigned StartNo) { // The compaction types may have been uncompactified back to the // global types. If so, we just write an empty table if (CTypes.size() == 0 ) { - output_vbr(0U, Out); + output_vbr(0U); return; } @@ -303,14 +1016,15 @@ void BytecodeWriter::outputCompactionTypes(unsigned StartNo) { unsigned NumTypes = CTypes.size() - StartNo; // Output the number of types. - output_vbr(NumTypes, Out); + output_vbr(NumTypes); for (unsigned i = StartNo; i < StartNo+NumTypes; ++i) - output_vbr(Table.getGlobalSlot(CTypes[i]), Out); + output_typeid(Table.getGlobalSlot(CTypes[i])); } void BytecodeWriter::outputCompactionTable() { - BytecodeBlock CTB(BytecodeFormat::CompactionTable, Out, true/*ElideIfEmpty*/); + BytecodeBlock CTB(BytecodeFormat::CompactionTableBlockID, *this, + true/*ElideIfEmpty*/); const std::vector<std::vector<const Value*> > &CT =Table.getCompactionTable(); // First thing is first, emit the type compaction table if there is one. @@ -325,16 +1039,16 @@ void BytecodeWriter::outputSymbolTable(const SymbolTable &MST) { // space! if ( MST.isEmpty() ) return; - BytecodeBlock SymTabBlock(BytecodeFormat::SymbolTable, Out, + BytecodeBlock SymTabBlock(BytecodeFormat::SymbolTableBlockID, *this, true/* ElideIfEmpty*/); //Symtab block header for types: [num entries] - output_vbr(MST.num_types(), Out); + output_vbr(MST.num_types()); for (SymbolTable::type_const_iterator TI = MST.type_begin(), TE = MST.type_end(); TI != TE; ++TI ) { //Symtab entry:[def slot #][name] - output_vbr((unsigned)Table.getSlot(TI->second), Out); - output(TI->first, Out, /*align=*/false); + output_typ |