-//===-- Writer.cpp - Library for writing VM bytecode files ----------------===//
-//
+//===-- Writer.cpp - Library for writing LLVM bytecode files --------------===//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// 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.
-//
-// Note that the performance of this library is not terribly important, because
-// it shouldn't be used by JIT type applications... so it is not a huge focus
-// at least. :)
-//
//===----------------------------------------------------------------------===//
#include "WriterInternals.h"
#include "llvm/Bytecode/WriteBytecodePass.h"
+#include "llvm/CallingConv.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/InlineAsm.h"
+#include "llvm/Instructions.h"
#include "llvm/Module.h"
#include "llvm/SymbolTable.h"
-#include "llvm/DerivedTypes.h"
-#include "Support/STLExtras.h"
-#include "Support/Statistic.h"
-#include "Config/string.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Support/Compressor.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/System/Program.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Statistic.h"
+#include <cstring>
#include <algorithm>
+using namespace llvm;
-namespace llvm {
+/// This value needs to be incremented every time the bytecode format changes
+/// so that the reader can distinguish which format of the bytecode file has
+/// been written.
+/// @brief The bytecode version number
+const unsigned BCVersionNum = 5;
static RegisterPass<WriteBytecodePass> X("emitbytecode", "Bytecode Writer");
-static Statistic<>
+static Statistic<>
BytesWritten("bytecodewriter", "Number of bytecode bytes written");
+//===----------------------------------------------------------------------===//
+//=== 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.
+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.
+}
+
+inline void BytecodeWriter::output(const std::string &s) {
+ unsigned Len = s.length();
+ output_vbr(Len); // Strings may have an arbitrary length.
+ Out.insert(Out.end(), s.begin(), s.end());
+}
+
+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.
+ uint32_t i = FloatToBits(FloatVal);
+ Out.push_back( static_cast<unsigned char>( (i ) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 8 ) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 16) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (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.
+ uint64_t i = DoubleToBits(DoubleVal);
+ Out.push_back( static_cast<unsigned char>( (i ) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 8 ) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 16) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 24) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 32) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 40) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (i >> 48) & 0xFF));
+ Out.push_back( static_cast<unsigned char>( (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;
+ }
+
+ if (HasLongFormat)
+ Writer.output(unsigned(Writer.size()-Loc), int(Loc-4));
+ else
+ Writer.output(unsigned(Writer.size()-Loc) << 5 | (Id & 0x1F), int(Loc-4));
+}
+
+//===----------------------------------------------------------------------===//
+//=== 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);
+ output_vbr(AT->getNumElements());
+ break;
+ }
+
+ case Type::PackedTyID: {
+ const PackedType *PT = cast<PackedType>(T);
+ int Slot = Table.getSlot(PT->getElementType());
+ assert(Slot != -1 && "Type used but not available!!");
+ output_typeid((unsigned)Slot);
+ output_vbr(PT->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;
+
+ 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");
+ assert(CE->getNumOperands() != 1 || CE->getOpcode() == Instruction::Cast);
+ output_vbr(1+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 if (isa<UndefValue>(CPV)) {
+ output_vbr(1U); // 1 -> UndefValue constant.
+ 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, e = CPA->getNumOperands(); i != e; ++i) {
+ int Slot = Table.getSlot(CPA->getOperand(i));
+ assert(Slot != -1 && "Constant used but not available!!");
+ output_vbr((unsigned)Slot);
+ }
+ break;
+ }
+
+ case Type::PackedTyID: {
+ const ConstantPacked *CP = cast<ConstantPacked>(CPV);
+
+ for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) {
+ int Slot = Table.getSlot(CP->getOperand(i));
+ assert(Slot != -1 && "Constant used but not available!!");
+ output_vbr((unsigned)Slot);
+ }
+ break;
+ }
+
+ case Type::StructTyID: {
+ const ConstantStruct *CPS = cast<ConstantStruct>(CPV);
+
+ for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i) {
+ int Slot = Table.getSlot(CPS->getOperand(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;
+}
+
+/// outputInlineAsm - InlineAsm's get emitted to the constant pool, so they can
+/// be shared by multiple uses.
+void BytecodeWriter::outputInlineAsm(const InlineAsm *IA) {
+ // Output a marker, so we know when we have one one parsing the constant pool.
+ // Note that this encoding is 5 bytes: not very efficient for a marker. Since
+ // unique inline asms are rare, this should hardly matter.
+ output_vbr(~0U);
+
+ output(IA->getAsmString());
+ output(IA->getConstraintString());
+ output_vbr(unsigned(IA->hasSideEffects()));
+}
+
+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 ===//
+//===----------------------------------------------------------------------===//
-BytecodeWriter::BytecodeWriter(std::deque<unsigned char> &o, const Module *M)
- : Out(o), Table(M, false) {
+// outputInstructionFormat0 - Output those weird 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
- outputSignature();
+ unsigned NumArgs = I->getNumOperands();
+ output_vbr(NumArgs + (isa<CastInst>(I) ||
+ isa<VAArgInst>(I) || Opcode == 56 || Opcode == 58));
+
+ 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 (Opcode == 56) { // Invoke escape sequence
+ output_vbr(cast<InvokeInst>(I)->getCallingConv());
+ } else if (Opcode == 58) { // Call escape sequence
+ output_vbr((cast<CallInst>(I)->getCallingConv() << 1) |
+ unsigned(cast<CallInst>(I)->isTailCall()));
+ }
+ } 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));
+ }
+ }
+}
+
+
+// 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 +
+ unsigned(Opcode == 56 || Opcode == 58));
+
+ // 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);
+ }
+
+ // If this is the escape sequence for call, emit the tailcall/cc info.
+ if (Opcode == 58) {
+ const CallInst *CI = cast<CallInst>(I);
+ output_vbr((CI->getCallingConv() << 1) | unsigned(CI->isTailCall()));
+ } else if (Opcode == 56) { // Invoke escape sequence.
+ output_vbr(cast<InvokeInst>(I)->getCallingConv());
+ }
+}
+
+
+// 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)
+ //
+ output(1 | (Opcode << 2) | (Type << 8) | (Slots[0] << 20));
+}
+
+
+// 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
+ //
+ output(2 | (Opcode << 2) | (Type << 8) | (Slots[0] << 16) | (Slots[1] << 24));
+}
+
+
+// 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
+ //
+ output(3 | (Opcode << 2) | (Type << 8) |
+ (Slots[0] << 14) | (Slots[1] << 20) | (Slots[2] << 26));
+}
+
+void BytecodeWriter::outputInstruction(const Instruction &I) {
+ assert(I.getOpcode() < 56 && "Opcode too big???");
+ unsigned Opcode = I.getOpcode();
+ unsigned NumOperands = I.getNumOperands();
+
+ // Encode 'tail call' as 61, 'volatile load' as 62, and 'volatile store' as
+ // 63.
+ if (const CallInst *CI = dyn_cast<CallInst>(&I)) {
+ if (CI->getCallingConv() == CallingConv::C) {
+ if (CI->isTailCall())
+ Opcode = 61; // CCC + Tail Call
+ else
+ ; // Opcode = Instruction::Call
+ } else if (CI->getCallingConv() == CallingConv::Fast) {
+ if (CI->isTailCall())
+ Opcode = 59; // FastCC + TailCall
+ else
+ Opcode = 60; // FastCC + Not Tail Call
+ } else {
+ Opcode = 58; // Call escape sequence.
+ }
+ } else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I)) {
+ if (II->getCallingConv() == CallingConv::Fast)
+ Opcode = 57; // FastCC invoke.
+ else if (II->getCallingConv() != CallingConv::C)
+ Opcode = 56; // Invoke escape sequence.
+
+ } else if (isa<LoadInst>(I) && cast<LoadInst>(I).isVolatile()) {
+ Opcode = 62;
+ } else 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 AllocationInst *AI = dyn_cast<AllocationInst>(&I)) {
+ assert(NumOperands == 1 && "Bogus allocation!");
+ if (AI->getAlignment()) {
+ Slots[1] = Log2_32(AI->getAlignment())+1;
+ if (Slots[1] > MaxOpSlot) MaxOpSlot = Slots[1];
+ NumOperands = 2;
+ }
+ } 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];
+ }
+ } else if (Opcode == 58) {
+ // If this is the escape sequence for call, emit the tailcall/cc info.
+ const CallInst &CI = cast<CallInst>(I);
+ ++NumOperands;
+ if (NumOperands <= 3) {
+ Slots[NumOperands-1] =
+ (CI.getCallingConv() << 1)|unsigned(CI.isTailCall());
+ if (Slots[NumOperands-1] > MaxOpSlot)
+ MaxOpSlot = Slots[NumOperands-1];
+ }
+ } else if (Opcode == 56) {
+ // Invoke escape seq has at least 4 operands to encode.
+ ++NumOperands;
+ }
+
+ // 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);
// 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;
bool hasNoEndianness = M->getEndianness() == Module::AnyEndianness;
bool hasNoPointerSize = M->getPointerSize() == Module::AnyPointerSize;
- // Output the version identifier... we are currently on bytecode version #0
- unsigned Version = (0 << 4) | isBigEndian | (hasLongPointers << 1) |
- (hasNoEndianness << 2) | (hasNoPointerSize << 3);
- output_vbr(Version, Out);
- align32(Out);
+ // Output the version identifier and other information.
+ unsigned Version = (BCVersionNum << 4) |
+ (unsigned)isBigEndian | (hasLongPointers << 1) |
+ (hasNoEndianness << 2) |
+ (hasNoPointerSize << 3);
+ output_vbr(Version);
+ // The Global type plane comes first
{
- BytecodeBlock CPool(BytecodeFormat::GlobalTypePlane, Out);
-
- // Write the type plane for types first because earlier planes (e.g. for a
- // primitive type like float) may have constants constructed using types
- // coming later (e.g., via getelementptr from a pointer type). The type
- // plane is needed before types can be fwd or bkwd referenced.
- const std::vector<const Value*> &Plane = Table.getPlane(Type::TypeTyID);
- assert(!Plane.empty() && "No types at all?");
- unsigned ValNo = Type::FirstDerivedTyID; // Start at the derived types...
- outputConstantsInPlane(Plane, ValNo); // Write out the types
+ BytecodeBlock CPool(BytecodeFormat::GlobalTypePlaneBlockID, *this);
+ outputTypes(Type::FirstDerivedTyID);
}
// The ModuleInfoBlock follows directly after the type information
outputSymbolTable(M->getSymbolTable());
}
+void BytecodeWriter::outputTypes(unsigned TypeNum) {
+ // Write the type plane for types first because earlier planes (e.g. for a
+ // primitive type like float) may have constants constructed using types
+ // coming later (e.g., via getelementptr from a pointer type). The type
+ // plane is needed before types can be fwd or bkwd referenced.
+ const std::vector<const Type*>& Types = Table.getTypes();
+ assert(!Types.empty() && "No types at all?");
+ assert(TypeNum <= Types.size() && "Invalid TypeNo index");
+
+ unsigned NumEntries = Types.size() - TypeNum;
+
+ // Output type header: [num entries]
+ output_vbr(NumEntries);
+
+ for (unsigned i = TypeNum; i < TypeNum+NumEntries; ++i)
+ outputType(Types[i]);
+}
+
// Helper function for outputConstants().
// Writes out all the constants in the plane Plane starting at entry StartNo.
-//
+//
void BytecodeWriter::outputConstantsInPlane(const std::vector<const Value*>
&Plane, unsigned StartNo) {
unsigned ValNo = StartNo;
-
- // Scan through and ignore function arguments/global values...
- for (; ValNo < Plane.size() && (isa<Argument>(Plane[ValNo]) ||
- isa<GlobalValue>(Plane[ValNo])); ValNo++)
+
+ // Scan through and ignore function arguments, global values, and constant
+ // strings.
+ for (; ValNo < Plane.size() &&
+ (isa<Argument>(Plane[ValNo]) || isa<GlobalValue>(Plane[ValNo]) ||
+ (isa<ConstantArray>(Plane[ValNo]) &&
+ cast<ConstantArray>(Plane[ValNo])->isString())); ValNo++)
/*empty*/;
unsigned NC = ValNo; // Number of constants
- for (; NC < Plane.size() &&
- (isa<Constant>(Plane[NC]) || isa<Type>(Plane[NC])); NC++)
+ for (; NC < Plane.size() && (isa<Constant>(Plane[NC]) ||
+ isa<InlineAsm>(Plane[NC])); NC++)
/*empty*/;
NC -= ValNo; // Convert from index into count
if (NC == 0) return; // Skip empty type planes...
+ // FIXME: Most slabs only have 1 or 2 entries! We should encode this much
+ // more compactly.
+
// 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);
-
- //cerr << "Emitting " << NC << " constants of type '"
- // << Plane.front()->getType()->getName() << "' = Slot #" << Slot << "\n";
+ output_typeid((unsigned)Slot);
for (unsigned i = ValNo; i < ValNo+NC; ++i) {
const Value *V = Plane[i];
- if (const Constant *CPV = dyn_cast<Constant>(V)) {
- //cerr << "Serializing value: <" << V->getType() << ">: " << V << ":"
- // << Out.size() << "\n";
- outputConstant(CPV);
- } else {
- outputType(cast<Type>(V));
- }
+ if (const Constant *C = dyn_cast<Constant>(V))
+ outputConstant(C);
+ else
+ outputInlineAsm(cast<InlineAsm>(V));
}
}
+static inline bool hasNullValue(const Type *Ty) {
+ return Ty != Type::LabelTy && Ty != Type::VoidTy && !isa<OpaqueType>(Ty);
+}
+
void BytecodeWriter::outputConstants(bool isFunction) {
- BytecodeBlock CPool(BytecodeFormat::ConstantPool, Out);
+ BytecodeBlock CPool(BytecodeFormat::ConstantPoolBlockID, *this,
+ true /* Elide block if empty */);
unsigned NumPlanes = Table.getNumPlanes();
- // Output the type plane before any constants!
- if (isFunction && NumPlanes > Type::TypeTyID) {
- const std::vector<const Value*> &Plane = Table.getPlane(Type::TypeTyID);
+ if (isFunction)
+ // Output the type plane before any constants!
+ outputTypes(Table.getModuleTypeLevel());
+ else
+ // Output module-level string constants before any other constants.
+ outputConstantStrings();
+
+ for (unsigned pno = 0; pno != NumPlanes; pno++) {
+ const std::vector<const Value*> &Plane = Table.getPlane(pno);
if (!Plane.empty()) { // Skip empty type planes...
- unsigned ValNo = Table.getModuleLevel(Type::TypeTyID);
+ unsigned ValNo = 0;
+ if (isFunction) // Don't re-emit module constants
+ ValNo += Table.getModuleLevel(pno);
+
+ if (hasNullValue(Plane[0]->getType())) {
+ // Skip zero initializer
+ if (ValNo == 0)
+ ValNo = 1;
+ }
+
+ // Write out constants in the plane
outputConstantsInPlane(Plane, ValNo);
}
}
-
- for (unsigned pno = 0; pno != NumPlanes; pno++)
- if (pno != Type::TypeTyID) { // Type plane handled above.
- const std::vector<const Value*> &Plane = Table.getPlane(pno);
- if (!Plane.empty()) { // Skip empty type planes...
- unsigned ValNo = 0;
- if (isFunction) // Don't re-emit module constants
- ValNo += Table.getModuleLevel(pno);
-
- if (pno >= Type::FirstDerivedTyID) {
- // Skip zero initializer
- if (ValNo == 0)
- ValNo = 1;
- }
-
- // Write out constants in the plane
- outputConstantsInPlane(Plane, ValNo);
- }
- }
}
static unsigned getEncodedLinkage(const GlobalValue *GV) {
switch (GV->getLinkage()) {
default: assert(0 && "Invalid linkage!");
- case GlobalValue::ExternalLinkage: return 0;
- case GlobalValue::WeakLinkage: return 1;
- case GlobalValue::AppendingLinkage: return 2;
- case GlobalValue::InternalLinkage: return 3;
- case GlobalValue::LinkOnceLinkage: return 4;
+ case GlobalValue::ExternalLinkage: return 0;
+ case GlobalValue::WeakLinkage: return 1;
+ case GlobalValue::AppendingLinkage: return 2;
+ case GlobalValue::InternalLinkage: return 3;
+ case GlobalValue::LinkOnceLinkage: return 4;
+ case GlobalValue::DLLImportLinkage: return 5;
+ case GlobalValue::DLLExportLinkage: return 6;
+ case GlobalValue::ExternalWeakLinkage: return 7;
}
}
void BytecodeWriter::outputModuleInfoBlock(const Module *M) {
- BytecodeBlock ModuleInfoBlock(BytecodeFormat::ModuleGlobalInfo, Out);
+ BytecodeBlock ModuleInfoBlock(BytecodeFormat::ModuleGlobalInfoBlockID, *this);
+
+ // Give numbers to sections as we encounter them.
+ unsigned SectionIDCounter = 0;
+ std::vector<std::string> SectionNames;
+ std::map<std::string, unsigned> SectionID;
// Output the types for the global variables in the module...
- for (Module::const_giterator I = M->gbegin(), End = M->gend(); I != End;++I) {
+ for (Module::const_global_iterator I = M->global_begin(),
+ End = M->global_end(); I != End; ++I) {
int Slot = Table.getSlot(I->getType());
assert(Slot != -1 && "Module global vars is broken!");
+ assert((I->hasInitializer() || !I->hasInternalLinkage()) &&
+ "Global must have an initializer or have external linkage!");
+
// Fields: bit0 = isConstant, bit1 = hasInitializer, bit2-4=Linkage,
- // bit5+ = Slot # for type
- unsigned oSlot = ((unsigned)Slot << 5) | (getEncodedLinkage(I) << 2) |
- (I->hasInitializer() << 1) | I->isConstant();
- output_vbr(oSlot, Out);
+ // bit5+ = Slot # for type.
+ bool HasExtensionWord = (I->getAlignment() != 0) || I->hasSection();
+
+ // If we need to use the extension byte, set linkage=3(internal) and
+ // initializer = 0 (impossible!).
+ if (!HasExtensionWord) {
+ unsigned oSlot = ((unsigned)Slot << 5) | (getEncodedLinkage(I) << 2) |
+ (I->hasInitializer() << 1) | (unsigned)I->isConstant();
+ output_vbr(oSlot);
+ } else {
+ unsigned oSlot = ((unsigned)Slot << 5) | (3 << 2) |
+ (0 << 1) | (unsigned)I->isConstant();
+ output_vbr(oSlot);
+
+ // The extension word has this format: bit 0 = has initializer, bit 1-3 =
+ // linkage, bit 4-8 = alignment (log2), bit 9 = has SectionID,
+ // bits 10+ = future use.
+ unsigned ExtWord = (unsigned)I->hasInitializer() |
+ (getEncodedLinkage(I) << 1) |
+ ((Log2_32(I->getAlignment())+1) << 4) |
+ ((unsigned)I->hasSection() << 9);
+ output_vbr(ExtWord);
+ if (I->hasSection()) {
+ // Give section names unique ID's.
+ unsigned &Entry = SectionID[I->getSection()];
+ if (Entry == 0) {
+ Entry = ++SectionIDCounter;
+ SectionNames.push_back(I->getSection());
+ }
+ output_vbr(Entry);
+ }
+ }
// 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...
+ // 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 != -1 && "Module slot calculator is broken!");
assert(Slot >= Type::FirstDerivedTyID && "Derived type not in range!");
- output_vbr((unsigned)Slot, Out);
+ assert(((Slot << 6) >> 6) == Slot && "Slot # too big!");
+ unsigned CC = I->getCallingConv()+1;
+ unsigned ID = (Slot << 5) | (CC & 15);
+
+ if (I->isExternal()) // If external, we don't have an FunctionInfo block.
+ ID |= 1 << 4;
+
+ if (I->getAlignment() || I->hasSection() || (CC & ~15) != 0 ||
+ (I->isExternal() && I->hasDLLImportLinkage()) ||
+ (I->isExternal() && I->hasExternalWeakLinkage())
+ )
+ ID |= 1 << 31; // Do we need an extension word?
+
+ output_vbr(ID);
+
+ if (ID & (1 << 31)) {
+ // Extension byte: bits 0-4 = alignment, bits 5-9 = top nibble of calling
+ // convention, bit 10 = hasSectionID., bits 11-12 = external linkage type
+ unsigned extLinkage = 0;
+
+ if (I->isExternal()) {
+ if (I->hasDLLImportLinkage()) {
+ extLinkage = 1;
+ } else if (I->hasExternalWeakLinkage()) {
+ extLinkage = 2;
+ }
+ }
+
+ ID = (Log2_32(I->getAlignment())+1) | ((CC >> 4) << 5) |
+ (I->hasSection() << 10) |
+ ((extLinkage & 3) << 11);
+ output_vbr(ID);
+
+ // Give section names unique ID's.
+ if (I->hasSection()) {
+ unsigned &Entry = SectionID[I->getSection()];
+ if (Entry == 0) {
+ Entry = ++SectionIDCounter;
+ SectionNames.push_back(I->getSection());
+ }
+ output_vbr(Entry);
+ }
+ }
}
- output_vbr((unsigned)Table.getSlot(Type::VoidTy), Out);
+ output_vbr((unsigned)Table.getSlot(Type::VoidTy) << 5);
- align32(Out);
+ // Emit the list of dependent libraries for the Module.
+ Module::lib_iterator LI = M->lib_begin();
+ Module::lib_iterator LE = M->lib_end();
+ output_vbr(unsigned(LE - LI)); // Emit the number of dependent libraries.
+ for (; LI != LE; ++LI)
+ output(*LI);
+
+ // Output the target triple from the module
+ output(M->getTargetTriple());
+
+ // Emit the table of section names.
+ output_vbr((unsigned)SectionNames.size());
+ for (unsigned i = 0, e = SectionNames.size(); i != e; ++i)
+ output(SectionNames[i]);
+
+ // Output the inline asm string.
+ output(M->getModuleInlineAsm());
+}
+
+void BytecodeWriter::outputInstructions(const Function *F) {
+ 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);
- // Only output the constant pool and other goodies if needed...
- if (!F->isExternal()) {
+ // If this is an external function, there is nothing else to emit!
+ if (F->isExternal()) return;
+
+ BytecodeBlock FunctionBlock(BytecodeFormat::FunctionBlockID, *this);
+ output_vbr(getEncodedLinkage(F));
- // Get slot information about the function...
- Table.incorporateFunction(F);
+ // Get slot information about the function...
+ Table.incorporateFunction(F);
- // Output information about the constants in the function...
+ if (Table.getCompactionTable().empty()) {
+ // Output information about the constants in the function if the compaction
+ // table is not being used.
outputConstants(true);
+ } else {
+ // Otherwise, emit the compaction table.
+ outputCompactionTable();
+ }
- // Output basic block nodes...
- for (Function::const_iterator I = F->begin(), E = F->end(); I != E; ++I)
- processBasicBlock(*I);
-
- // If needed, output the symbol table for the function...
- outputSymbolTable(F->getSymbolTable());
-
- Table.purgeFunction();
+ // Output all of the instructions in the body of the function
+ outputInstructions(F);
+
+ // If needed, output the symbol table for the function...
+ outputSymbolTable(F->getSymbolTable());
+
+ Table.purgeFunction();
+}
+
+void BytecodeWriter::outputCompactionTablePlane(unsigned PlaneNo,
+ const std::vector<const Value*> &Plane,
+ unsigned StartNo) {
+ unsigned End = Table.getModuleLevel(PlaneNo);
+ if (Plane.empty() || StartNo == End || End == 0) return; // Nothing to emit
+ assert(StartNo < End && "Cannot emit negative range!");
+ assert(StartNo < Plane.size() && End <= Plane.size());
+
+ // Do not emit the null initializer!
+ ++StartNo;
+
+ // Figure out which encoding to use. By far the most common case we have is
+ // to emit 0-2 entries in a compaction table plane.
+ switch (End-StartNo) {
+ case 0: // Avoid emitting two vbr's if possible.
+ case 1:
+ case 2:
+ output_vbr((PlaneNo << 2) | End-StartNo);
+ break;
+ default:
+ // Output the number of things.
+ 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]));
}
+void BytecodeWriter::outputCompactionTypes(unsigned StartNo) {
+ // Get the compaction type table from the slot calculator
+ const std::vector<const Type*> &CTypes = Table.getCompactionTypes();
+
+ // 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);
+ return;
+ }
+
+ assert(CTypes.size() >= StartNo && "Invalid compaction types start index");
-void BytecodeWriter::processBasicBlock(const BasicBlock &BB) {
- BytecodeBlock FunctionBlock(BytecodeFormat::BasicBlock, Out);
- // Process all the instructions in the bb...
- for(BasicBlock::const_iterator I = BB.begin(), E = BB.end(); I != E; ++I)
- processInstruction(*I);
+ // Determine how many types to write
+ unsigned NumTypes = CTypes.size() - StartNo;
+
+ // Output the number of types.
+ output_vbr(NumTypes);
+
+ for (unsigned i = StartNo; i < StartNo+NumTypes; ++i)
+ output_typeid(Table.getGlobalSlot(CTypes[i]));
+}
+
+void BytecodeWriter::outputCompactionTable() {
+ // Avoid writing the compaction table at all if there is no content.
+ if (Table.getCompactionTypes().size() >= Type::FirstDerivedTyID ||
+ (!Table.CompactionTableIsEmpty())) {
+ BytecodeBlock CTB(BytecodeFormat::CompactionTableBlockID, *this,
+ true/*ElideIfEmpty*/);
+ const std::vector<std::vector<const Value*> > &CT =
+ Table.getCompactionTable();
+
+ // First things first, emit the type compaction table if there is one.
+ outputCompactionTypes(Type::FirstDerivedTyID);
+
+ for (unsigned i = 0, e = CT.size(); i != e; ++i)
+ outputCompactionTablePlane(i, CT[i], 0);
+ }
}
void BytecodeWriter::outputSymbolTable(const SymbolTable &MST) {
- BytecodeBlock FunctionBlock(BytecodeFormat::SymbolTable, Out);
+ // Do not output the Bytecode block for an empty symbol table, it just wastes
+ // space!
+ if (MST.isEmpty()) return;
+
+ BytecodeBlock SymTabBlock(BytecodeFormat::SymbolTableBlockID, *this,
+ true/*ElideIfEmpty*/);
- for (SymbolTable::const_iterator TI = MST.begin(); TI != MST.end(); ++TI) {
- SymbolTable::type_const_iterator I = MST.type_begin(TI->first);
- SymbolTable::type_const_iterator End = MST.type_end(TI->first);
+ // Write the number of types
+ output_vbr(MST.num_types());
+
+ // Write each of the types
+ for (SymbolTable::type_const_iterator TI = MST.type_begin(),
+ TE = MST.type_end(); TI != TE; ++TI) {
+ // Symtab entry:[def slot #][name]
+ output_typeid((unsigned)Table.getSlot(TI->second));
+ output(TI->first);
+ }
+
+ // Now do each of the type planes in order.
+ for (SymbolTable::plane_const_iterator PI = MST.plane_begin(),
+ PE = MST.plane_end(); PI != PE; ++PI) {
+ SymbolTable::value_const_iterator I = MST.value_begin(PI->first);
+ SymbolTable::value_const_iterator End = MST.value_end(PI->first);
int Slot;
-
+
if (I == End) continue; // Don't mess with an absent type...
- // Symtab block header: [num entries][type id number]
- output_vbr(MST.type_size(TI->first), Out);
+ // Write the number of values in this plane
+ output_vbr((unsigned)PI->second.size());
- Slot = Table.getSlot(TI->first);
+ // Write the slot number of the type for this plane
+ Slot = Table.getSlot(PI->first);
assert(Slot != -1 && "Type in symtab, but not in table!");
- output_vbr((unsigned)Slot, Out);
+ output_typeid((unsigned)Slot);
+ // Write each of the values in this plane
for (; I != End; ++I) {
// Symtab entry: [def slot #][name]
Slot = Table.getSlot(I->second);
assert(Slot != -1 && "Value in symtab but has no slot number!!");
- output_vbr((unsigned)Slot, Out);
- output(I->first, Out, false); // Don't force alignment...
+ output_vbr((unsigned)Slot);
+ output(I->first);
}
}
}
-void WriteBytecodeToFile(const Module *C, std::ostream &Out) {
- assert(C && "You can't write a null module!!");
+void llvm::WriteBytecodeToFile(const Module *M, std::ostream &Out,
+ bool compress) {
+ assert(M && "You can't write a null module!!");
- std::deque<unsigned char> Buffer;
+ // Make sure that std::cout is put into binary mode for systems
+ // that care.
+ if (&Out == std::cout)
+ sys::Program::ChangeStdoutToBinary();
- // This object populates buffer for us...
- BytecodeWriter BCW(Buffer, C);
+ // Create a vector of unsigned char for the bytecode output. We
+ // reserve 256KBytes of space in the vector so that we avoid doing
+ // lots of little allocations. 256KBytes is sufficient for a large
+ // proportion of the bytecode files we will encounter. Larger files
+ // will be automatically doubled in size as needed (std::vector
+ // behavior).
+ std::vector<unsigned char> Buffer;
+ Buffer.reserve(256 * 1024);
- // Keep track of how much we've written...
+ // The BytecodeWriter populates Buffer for us.
+ BytecodeWriter BCW(Buffer, M);
+
+ // Keep track of how much we've written
BytesWritten += Buffer.size();
- // Okay, write the deque out to the ostream now... the deque is not
- // sequential in memory, however, so write out as much as possible in big
- // chunks, until we're done.
- //
- std::deque<unsigned char>::const_iterator I = Buffer.begin(),E = Buffer.end();
- while (I != E) { // Loop until it's all written
- // Scan to see how big this chunk is...
- const unsigned char *ChunkPtr = &*I;
- const unsigned char *LastPtr = ChunkPtr;
- while (I != E) {
- const unsigned char *ThisPtr = &*++I;
- if (LastPtr+1 != ThisPtr) { // Advanced by more than a byte of memory?
- ++LastPtr;
- break;
- }
- LastPtr = ThisPtr;
- }
-
- // Write out the chunk...
- Out.write((char*)ChunkPtr, LastPtr-ChunkPtr);
+ // Determine start and end points of the Buffer
+ const unsigned char *FirstByte = &Buffer.front();
+
+ // If we're supposed to compress this mess ...
+ if (compress) {
+
+ // We signal compression by using an alternate magic number for the
+ // file. The compressed bytecode file's magic number is "llvc" instead
+ // of "llvm".
+ char compressed_magic[4];
+ compressed_magic[0] = 'l';
+ compressed_magic[1] = 'l';
+ compressed_magic[2] = 'v';
+ compressed_magic[3] = 'c';
+
+ Out.write(compressed_magic,4);
+
+ // Compress everything after the magic number (which we altered)
+ uint64_t zipSize = Compressor::compressToStream(
+ (char*)(FirstByte+4), // Skip the magic number
+ Buffer.size()-4, // Skip the magic number
+ Out // Where to write compressed data
+ );
+
+ } else {
+
+ // We're not compressing, so just write the entire block.
+ Out.write((char*)FirstByte, Buffer.size());
}
+ // make sure it hits disk now
Out.flush();
}
-
-} // End llvm namespace
projects / oota-llvm.git / blobdiff