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bug 263:

Browse Source 
- encode/decode target triple and dependent libraries
bug 401:
- fix encoding/decoding of FP values to be little-endian only
bug 402:
- initial (compatible) cut at 24-bit types instead of 32-bit
- reduce size of block headers by 50%
Other:
- cleanup Writer by consolidating to one compilation unit, rem. other files
- use a std::vector instead of std::deque so the buffer can be allocated
  in multiples of 64KByte chunks rather than in multiples of some smaller
  (default) number.

llvm-svn: 15210
This commit is contained in:
Reid Spencer 2004-07-25 18:07:36 +00:00
parent 4b76a409e5
commit 3043e82af5
7 changed files with 1004 additions and 812 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

164
lib/Bytecode/Reader/Reader.cpp
View File

@ -156,24 +156,79 @@ inline void BytecodeReader::read_data(void *Ptr, void *End) {
/// Read a float value in little-endian order
inline void BytecodeReader::read_float(float& FloatVal) {
/// FIXME: This is a broken implementation! It reads
/// it in a platform-specific endianess. Need to make
/// it little endian always.
read_data(&FloatVal, &FloatVal+1);
if (hasPlatformSpecificFloatingPoint) {
read_data(&FloatVal, &FloatVal+1);
} else {
/// 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.i = At[0] | (At[1] << 8) | (At[2] << 16) | (At[3] << 24);
At+=sizeof(uint32_t);
FloatVal = FloatUnion.f;
}
}
/// Read a double value in little-endian order
inline void BytecodeReader::read_double(double& DoubleVal) {
/// FIXME: This is a broken implementation! It reads
/// it in a platform-specific endianess. Need to make
/// it little endian always.
read_data(&DoubleVal, &DoubleVal+1);
if (hasPlatformSpecificFloatingPoint) {
read_data(&DoubleVal, &DoubleVal+1);
} else {
/// 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.i = At[0] | (At[1] << 8) | (At[2] << 16) | (At[3] << 24) |
(uint64_t(At[4]) << 32) | (uint64_t(At[5]) << 40) |
(uint64_t(At[6]) << 48) | (uint64_t(At[7]) << 56);
At+=sizeof(uint64_t);
DoubleVal = DoubleUnion.d;
}
}
/// Read a block header and obtain its type and size
inline void BytecodeReader::read_block(unsigned &Type, unsigned &Size) {
Type = read_uint();
Size = read_uint();
if ( hasLongBlockHeaders ) {
Type = read_uint();
Size = read_uint();
switch (Type) {
case BytecodeFormat::Reserved_DoNotUse :
error("Reserved_DoNotUse used as Module Type?");
Type = BytecodeFormat::Module; break;
case BytecodeFormat::Module:
Type = BytecodeFormat::ModuleBlockID; break;
case BytecodeFormat::Function:
Type = BytecodeFormat::FunctionBlockID; break;
case BytecodeFormat::ConstantPool:
Type = BytecodeFormat::ConstantPoolBlockID; break;
case BytecodeFormat::SymbolTable:
Type = BytecodeFormat::SymbolTableBlockID; break;
case BytecodeFormat::ModuleGlobalInfo:
Type = BytecodeFormat::ModuleGlobalInfoBlockID; break;
case BytecodeFormat::GlobalTypePlane:
Type = BytecodeFormat::GlobalTypePlaneBlockID; break;
case BytecodeFormat::InstructionList:
Type = BytecodeFormat::InstructionListBlockID; break;
case BytecodeFormat::CompactionTable:
Type = BytecodeFormat::CompactionTableBlockID; break;
case BytecodeFormat::BasicBlock:
/// This block type isn't used after version 1.1. However, we have to
/// still allow the value in case this is an old bc format file.
/// We just let its value creep thru.
break;
default:
error("Invalid module type found: " + utostr(Type));
break;
}
} else {
Size = read_uint();
Type = Size & 0x1F; // mask low order five bits
Size >>= 5; // get rid of five low order bits, leaving high 27
}
BlockStart = At;
if (At + Size > BlockEnd)
error("Attempt to size a block past end of memory");
@ -216,6 +271,9 @@ inline bool BytecodeReader::sanitizeTypeId(unsigned &TypeId) {
/// @see sanitizeTypeId
inline bool BytecodeReader::read_typeid(unsigned &TypeId) {
TypeId = read_vbr_uint();
if ( !has32BitTypes )
if ( TypeId == 0x00FFFFFF )
TypeId = read_vbr_uint();
return sanitizeTypeId(TypeId);
}
@ -1504,7 +1562,7 @@ void BytecodeReader::ParseFunctionBody(Function* F) {
read_block(Type, Size);
switch (Type) {
case BytecodeFormat::ConstantPool:
case BytecodeFormat::ConstantPoolBlockID:
if (!InsertedArguments) {
// Insert arguments into the value table before we parse the first basic
// block in the function, but after we potentially read in the
@ -1516,7 +1574,7 @@ void BytecodeReader::ParseFunctionBody(Function* F) {
ParseConstantPool(FunctionValues, FunctionTypes, true);
break;
case BytecodeFormat::CompactionTable:
case BytecodeFormat::CompactionTableBlockID:
ParseCompactionTable();
break;
@ -1534,7 +1592,7 @@ void BytecodeReader::ParseFunctionBody(Function* F) {
break;
}
case BytecodeFormat::InstructionList: {
case BytecodeFormat::InstructionListBlockID: {
// Insert arguments into the value table before we parse the instruction
// list for the function, but after we potentially read in the compaction
// table.
@ -1549,7 +1607,7 @@ void BytecodeReader::ParseFunctionBody(Function* F) {
break;
}
case BytecodeFormat::SymbolTable:
case BytecodeFormat::SymbolTableBlockID:
ParseSymbolTable(F, &F->getSymbolTable());
break;
@ -1784,13 +1842,28 @@ void BytecodeReader::ParseModuleGlobalInfo() {
error("Invalid function type (type type) found");
}
if (hasInconsistentModuleGlobalInfo)
align32();
// Now that the function signature list is set up, reverse it so that we can
// remove elements efficiently from the back of the vector.
std::reverse(FunctionSignatureList.begin(), FunctionSignatureList.end());
// If this bytecode format has dependent library information in it ..
if (!hasNoDependentLibraries) {
// Read in the number of dependent library items that follow
unsigned num_dep_libs = read_vbr_uint();
std::string dep_lib;
while( num_dep_libs-- ) {
dep_lib = read_str();
TheModule->linsert(dep_lib);
}
// Read target triple and place into the module
std::string triple = read_str();
TheModule->setTargetTriple(triple);
}
if (hasInconsistentModuleGlobalInfo)
align32();
// This is for future proofing... in the future extra fields may be added that
// we don't understand, so we transparently ignore them.
//
@ -1820,6 +1893,10 @@ void BytecodeReader::ParseVersionInfo() {
hasExplicitPrimitiveZeros = false;
hasRestrictedGEPTypes = false;
hasTypeDerivedFromValue = false;
hasLongBlockHeaders = false;
hasPlatformSpecificFloatingPoint = false;
has32BitTypes = false;
hasNoDependentLibraries = false;
switch (RevisionNum) {
case 0: // LLVM 1.0, 1.1 release version
@ -1827,6 +1904,7 @@ void BytecodeReader::ParseVersionInfo() {
hasInconsistentModuleGlobalInfo = true;
hasExplicitPrimitiveZeros = true;
// FALL THROUGH
case 1: // LLVM 1.2 release version
// LLVM 1.2 added explicit support for emitting strings efficiently.
@ -1846,7 +1924,35 @@ void BytecodeReader::ParseVersionInfo() {
hasTypeDerivedFromValue = true;
// FALL THROUGH
case 2: // LLVM 1.3 release version
case 2: /// 1.2.5 (mid-release) version
/// LLVM 1.2 and earlier had two-word block headers. This is a bit wasteful,
/// especially for small files where the 8 bytes per block is a large fraction
/// of the total block size. In LLVM 1.3, the block type and length are
/// compressed into a single 32-bit unsigned integer. 27 bits for length, 5
/// bits for block type.
hasLongBlockHeaders = true;
/// LLVM 1.2 and earlier wrote floating point values in a platform specific
/// bit ordering. This was fixed in LLVM 1.3, but we still need to be backwards
/// compatible.
hasPlatformSpecificFloatingPoint = true;
/// LLVM 1.2 and earlier wrote type slot numbers as vbr_uint32. In LLVM 1.3
/// this has been reduced to vbr_uint24. It shouldn't make much difference
/// since we haven't run into a module with > 24 million types, but for safety
/// the 24-bit restriction has been enforced in 1.3 to free some bits in
/// various places and to ensure consistency.
has32BitTypes = true;
/// LLVM 1.2 and earlier did not provide a target triple nor a list of
/// libraries on which the bytecode is dependent. LLVM 1.3 provides these
/// features, for use in future versions of LLVM.
hasNoDependentLibraries = true;
// FALL THROUGH
case 3: // LLVM 1.3 release version
break;
default:
@ -1870,7 +1976,7 @@ void BytecodeReader::ParseModule() {
// Read into instance variables...
ParseVersionInfo();
align32(); /// FIXME: Is this redundant? VI is first and 4 bytes!
align32();
bool SeenModuleGlobalInfo = false;
bool SeenGlobalTypePlane = false;
@ -1881,7 +1987,7 @@ void BytecodeReader::ParseModule() {
switch (Type) {
case BytecodeFormat::GlobalTypePlane:
case BytecodeFormat::GlobalTypePlaneBlockID:
if (SeenGlobalTypePlane)
error("Two GlobalTypePlane Blocks Encountered!");
@ -1889,22 +1995,22 @@ void BytecodeReader::ParseModule() {
SeenGlobalTypePlane = true;
break;
case BytecodeFormat::ModuleGlobalInfo:
case BytecodeFormat::ModuleGlobalInfoBlockID:
if (SeenModuleGlobalInfo)
error("Two ModuleGlobalInfo Blocks Encountered!");
ParseModuleGlobalInfo();
SeenModuleGlobalInfo = true;
break;
case BytecodeFormat::ConstantPool:
case BytecodeFormat::ConstantPoolBlockID:
ParseConstantPool(ModuleValues, ModuleTypes,false);
break;
case BytecodeFormat::Function:
case BytecodeFormat::FunctionBlockID:
ParseFunctionLazily();
break;
case BytecodeFormat::SymbolTable:
case BytecodeFormat::SymbolTableBlockID:
ParseSymbolTable(0, &TheModule->getSymbolTable());
break;
@ -1967,14 +2073,16 @@ void BytecodeReader::ParseBytecode(BufPtr Buf, unsigned Length,
error("Invalid bytecode signature: " + utostr(Sig));
}
// Tell the handler we're starting a module
if (Handler) Handler->handleModuleBegin(ModuleID);
// Get the module block and size and verify
// Get the module block and size and verify. This is handled specially
// because the module block/size is always written in long format. Other
// blocks are written in short format so the read_block method is used.
unsigned Type, Size;
read_block(Type, Size);
if (Type != BytecodeFormat::Module) {
Type = read_uint();
Size = read_uint();
if (Type != BytecodeFormat::ModuleBlockID) {
error("Expected Module Block! Type:" + utostr(Type) + ", Size:"
+ utostr(Size));
}

35
lib/Bytecode/Reader/Reader.h
View File

@ -56,6 +56,7 @@ public:
/// @name Types
/// @{
public:
/// @brief A convenience type for the buffer pointer
typedef const unsigned char* BufPtr;
@ -268,6 +269,36 @@ private:
/// from Value style of bytecode file is being read.
bool hasTypeDerivedFromValue;
/// LLVM 1.2 and earlier encoded block headers as two uint (8 bytes), one for
/// the size and one for the type. This is a bit wasteful, especially for small
/// files where the 8 bytes per block is a large fraction of the total block
/// size. In LLVM 1.3, the block type and length are encoded into a single
/// uint32 by restricting the number of block types (limit 31) and the maximum
/// size of a block (limit 2^27-1=134,217,727). Note that the module block
/// still uses the 8-byte format so the maximum size of a file can be
/// 2^32-1 bytes long.
bool hasLongBlockHeaders;
/// LLVM 1.2 and earlier wrote floating point values in a platform specific
/// bit ordering. This was fixed in LLVM 1.3
bool hasPlatformSpecificFloatingPoint;
/// LLVM 1.2 and earlier wrote type slot numbers as vbr_uint32. In LLVM 1.3
/// this has been reduced to vbr_uint24. It shouldn't make much difference
/// since we haven't run into a module with > 24 million types, but for safety
/// the 24-bit restriction has been enforced in 1.3 to free some bits in
/// various places and to ensure consistency. In particular, global vars are
/// restricted to 24-bits.
bool has32BitTypes;
/// LLVM 1.2 and earlier did not provide a target triple nor a list of
/// libraries on which the bytecode is dependent. LLVM 1.3 provides these
/// features, for use in future versions of LLVM.
bool hasNoDependentLibraries;
/// LLVM 1.2 and earlier encoded the file version as part of the module block
/// but this information may be needed to
/// CompactionTable - If a compaction table is active in the current function,
/// this is the mapping that it contains.
std::vector<const Type*> CompactionTypes;
@ -430,6 +461,10 @@ private:
/// @brief Read an unsigned integer with variable bit rate encoding
inline unsigned read_vbr_uint();
/// @brief Read an unsigned integer of no more than 24-bits with variable
/// bit rate encoding.
inline unsigned read_vbr_uint24();
/// @brief Read an unsigned 64-bit integer with variable bit rate encoding.
inline uint64_t read_vbr_uint64();

220
lib/Bytecode/Writer/ConstantWriter.cpp
View File

@ -1,220 +0,0 @@
//===-- ConstantWriter.cpp - Functions for writing constants --------------===//
//
// 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 file implements the routines for encoding constants to a bytecode
// stream.
//
//===----------------------------------------------------------------------===//
#include "WriterInternals.h"
#include "llvm/Constants.h"
#include "llvm/SymbolTable.h"
#include "llvm/DerivedTypes.h"
#include "Support/Statistic.h"
using namespace llvm;
void BytecodeWriter::outputType(const Type *T) {
output_vbr((unsigned)T->getTypeID(), Out);
// 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_vbr((unsigned)Slot, Out);
// Output the number of arguments to function (+1 if varargs):
output_vbr((unsigned)MT->getNumParams()+MT->isVarArg(), Out);
// 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_vbr((unsigned)Slot, Out);
}
// Terminate list with VoidTy if we are a varargs function...
if (MT->isVarArg())
output_vbr((unsigned)Type::VoidTyID, Out);
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_vbr((unsigned)Slot, Out);
//std::cerr << "Type slot = " << Slot << " Type = " << T->getName() << endl;
output_vbr(AT->getNumElements(), Out);
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_vbr((unsigned)Slot, Out);
}
// Terminate list with VoidTy
output_vbr((unsigned)Type::VoidTyID, Out);
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_vbr((unsigned)Slot, Out);
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(), Out); // flags as an expr
output_vbr(CE->getOpcode(), Out); // 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, Out);
Slot = Table.getSlot((*OI)->getType());
output_vbr((unsigned)Slot, Out);
}
return;
} else {
output_vbr(0U, Out); // flag as not a ConstantExpr
}
switch (CPV->getType()->getTypeID()) {
case Type::BoolTyID: // Boolean Types
if (cast<ConstantBool>(CPV)->getValue())
output_vbr(1U, Out);
else
output_vbr(0U, Out);
break;
case Type::UByteTyID: // Unsigned integer types...
case Type::UShortTyID:
case Type::UIntTyID:
case Type::ULongTyID:
output_vbr(cast<ConstantUInt>(CPV)->getValue(), Out);
break;
case Type::SByteTyID: // Signed integer types...
case Type::ShortTyID:
case Type::IntTyID:
case Type::LongTyID:
output_vbr(cast<ConstantSInt>(CPV)->getValue(), Out);
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, Out);
}
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, Out);
}
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, Out);
break;
}
case Type::DoubleTyID: {
double Tmp = cast<ConstantFP>(CPV)->getValue();
output_double(Tmp, Out);
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), Out);
output_vbr(Type::VoidTyID, Out);
// 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_vbr((unsigned)Slot, Out);
// 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(), Out);
}
}

348
lib/Bytecode/Writer/InstructionWriter.cpp
View File

@ -1,348 +0,0 @@
//===-- InstructionWriter.cpp - Functions for writing instructions --------===//
//
// 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 file implements the routines for encoding instruction opcodes to a
// bytecode stream.
//
//===----------------------------------------------------------------------===//
#include "WriterInternals.h"
#include "llvm/Module.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "Support/Statistic.h"
#include <algorithm>
using namespace llvm;
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>]
//
static void outputInstructionFormat0(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table,
unsigned Type, std::deque<uchar> &Out) {
// Opcode must have top two bits clear...
output_vbr(Opcode << 2, Out); // Instruction Opcode ID
output_vbr(Type, Out); // Result type
unsigned NumArgs = I->getNumOperands();
output_vbr(NumArgs + (isa<CastInst>(I) || isa<VANextInst>(I) ||
isa<VAArgInst>(I)), Out);
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, Out);
}
if (isa<CastInst>(I) || isa<VAArgInst>(I)) {
int Slot = Table.getSlot(I->getType());
assert(Slot != -1 && "Cast return type unknown?");
output_vbr((unsigned)Slot, Out);
} else if (const VANextInst *VAI = dyn_cast<VANextInst>(I)) {
int Slot = Table.getSlot(VAI->getArgType());
assert(Slot != -1 && "VarArg argument type unknown?");
output_vbr((unsigned)Slot, Out);
}
} else {
int Slot = Table.getSlot(I->getOperand(0));
assert(Slot >= 0 && "No slot number for value!?!?");
output_vbr(unsigned(Slot), Out);
// 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), Out);
}
}
align32(Out); // 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>]
//
static void outputInstrVarArgsCall(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table, unsigned Type,
std::deque<uchar> &Out) {
assert(isa<CallInst>(I) || isa<InvokeInst>(I));
// Opcode must have top two bits clear...
output_vbr(Opcode << 2, Out); // Instruction Opcode ID
output_vbr(Type, Out); // 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, Out);
// 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, Out);
}
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_vbr((unsigned)Slot, Out);
// Output arg ID itself
Slot = Table.getSlot(I->getOperand(i));
assert(Slot >= 0 && "No slot number for value!?!?");
output_vbr((unsigned)Slot, Out);
}
align32(Out); // We must maintain correct alignment!
}
// outputInstructionFormat1 - Output one operand instructions, knowing that no
// operand index is >= 2^12.
//
static void outputInstructionFormat1(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table,
unsigned *Slots, unsigned Type,
std::deque<uchar> &Out) {
// 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, Out);
}
// outputInstructionFormat2 - Output two operand instructions, knowing that no
// operand index is >= 2^8.
//
static void outputInstructionFormat2(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table,
unsigned *Slots, unsigned Type,
std::deque<uchar> &Out) {
// 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, Out);
}
// outputInstructionFormat3 - Output three operand instructions, knowing that no
// operand index is >= 2^6.
//
static void outputInstructionFormat3(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table,
unsigned *Slots, unsigned Type,
std::deque<uchar> &Out) {
// 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, Out);
}
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, Out);
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, Out);
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, Table, Slots, Type, Out);
return;
}
break;
case 2:
if (MaxOpSlot < (1 << 8)) {
outputInstructionFormat2(&I, Opcode, Table, Slots, Type, Out);
return;
}
break;
case 3:
if (MaxOpSlot < (1 << 6)) {
outputInstructionFormat3(&I, Opcode, Table, Slots, Type, Out);
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, Out);
}

809
lib/Bytecode/Writer/Writer.cpp
View File

@ -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_typeid((unsigned)Table.getSlot(TI->second));
output(TI->first, /*align=*/false);
}
// Now do each of the type planes in order.
@ -347,29 +1061,30 @@ void BytecodeWriter::outputSymbolTable(const SymbolTable &MST) {
if (I == End) continue; // Don't mess with an absent type...
// Symtab block header: [num entries][type id number]
output_vbr(MST.type_size(PI->first), Out);
output_vbr(MST.type_size(PI->first));
Slot = Table.getSlot(PI->first);
assert(Slot != -1 && "Type in symtab, but not in table!");
output_vbr((unsigned)Slot, Out);
output_typeid((unsigned)Slot);
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, false); // Don't force alignment...
}
}
}
void llvm::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) {
assert(M && "You can't write a null module!!");
std::deque<unsigned char> Buffer;
std::vector<unsigned char> Buffer;
Buffer.reserve(64 * 1024); // avoid lots of little reallocs
// This object populates buffer for us...
BytecodeWriter BCW(Buffer, C);
BytecodeWriter BCW(Buffer, M);
// Keep track of how much we've written...
BytesWritten += Buffer.size();
@ -379,7 +1094,7 @@ void llvm::WriteBytecodeToFile(const Module *C, std::ostream &Out) {
// chunks, until we're done.
//
std::deque<unsigned char>::const_iterator I = Buffer.begin(),E = Buffer.end();
std::vector<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;

99
lib/Bytecode/Writer/WriterInternals.h
View File

@ -19,19 +19,21 @@
#ifndef LLVM_LIB_BYTECODE_WRITER_WRITERINTERNALS_H
#define LLVM_LIB_BYTECODE_WRITER_WRITERINTERNALS_H
#include "WriterPrimitives.h"
#include "SlotCalculator.h"
#include "llvm/Bytecode/Writer.h"
#include "llvm/Bytecode/Format.h"
#include "llvm/Instruction.h"
#include "Support/DataTypes.h"
#include <string>
#include <vector>
namespace llvm {
class BytecodeWriter {
std::deque<unsigned char> &Out;
std::vector<unsigned char> &Out;
SlotCalculator Table;
public:
BytecodeWriter(std::deque<unsigned char> &o, const Module *M);
BytecodeWriter(std::vector<unsigned char> &o, const Module *M);
private:
void outputConstants(bool isFunction);
@ -44,6 +46,25 @@ private:
unsigned StartNo);
void outputInstructions(const Function *F);
void outputInstruction(const Instruction &I);
void outputInstructionFormat0(const Instruction *I, unsigned Opcode,
const SlotCalculator &Table,
unsigned Type);
void outputInstrVarArgsCall(const Instruction *I,
unsigned Opcode,
const SlotCalculator &Table,
unsigned Type) ;
inline void outputInstructionFormat1(const Instruction *I,
unsigned Opcode,
unsigned *Slots,
unsigned Type) ;
inline void outputInstructionFormat2(const Instruction *I,
unsigned Opcode,
unsigned *Slots,
unsigned Type) ;
inline void outputInstructionFormat3(const Instruction *I,
unsigned Opcode,
unsigned *Slots,
unsigned Type) ;
void outputModuleInfoBlock(const Module *C);
void outputSymbolTable(const SymbolTable &ST);
@ -52,48 +73,70 @@ private:
unsigned StartNo);
void outputConstant(const Constant *CPV);
void outputType(const Type *T);
/// @brief Unsigned integer output primitive
inline void output(unsigned i, int pos = -1);
/// @brief Signed integer output primitive
inline void output(int i);
/// @brief 64-bit variable bit rate output primitive.
inline void output_vbr(uint64_t i);
/// @brief 32-bit variable bit rate output primitive.
inline void output_vbr(unsigned i);
/// @brief Signed 64-bit variable bit rate output primitive.
inline void output_vbr(int64_t i);
/// @brief Signed 32-bit variable bit rate output primitive.
inline void output_vbr(int i);
/// Emit the minimal number of bytes that will bring us to 32 bit alignment.
/// @brief 32-bit alignment output primitive
inline void align32();
inline void output(const std::string &s, bool Aligned = true);
inline void output_data(const void *Ptr, const void *End);
inline void output_float(float& FloatVal);
inline void output_double(double& DoubleVal);
inline void output_typeid(unsigned i);
inline size_t size() const { return Out.size(); }
inline void resize(size_t S) { Out.resize(S); }
friend class BytecodeBlock;
};
/// BytecodeBlock - Little helper class is used by the bytecode writer to help
/// do backpatching of bytecode block sizes really easily. It backpatches when
/// it goes out of scope.
///
class BytecodeBlock {
unsigned Id;
unsigned Loc;
std::deque<unsigned char> &Out;
BytecodeWriter& Writer;
/// ElideIfEmpty - If this is true and the bytecode block ends up being empty,
/// the block can remove itself from the output stream entirely.
bool ElideIfEmpty;
/// If this is true then the block is written with a long format header using
/// a uint (32-bits) for both the block id and size. Otherwise, it uses the
/// short format which is a single uint with 27 bits for size and 5 bits for
/// the block id. Both formats are used in a bc file with version 1.3.
/// Previously only the long format was used.
bool HasLongFormat;
BytecodeBlock(const BytecodeBlock &); // do not implement
void operator=(const BytecodeBlock &); // do not implement
public:
inline BytecodeBlock(unsigned ID, std::deque<unsigned char> &o,
bool elideIfEmpty = false)
: Out(o), ElideIfEmpty(elideIfEmpty) {
output(ID, Out);
output(0U, Out); // Reserve the space for the block size...
Loc = Out.size();
}
inline BytecodeBlock(unsigned ID, BytecodeWriter& w,
bool elideIfEmpty = false, bool hasLongFormat = false);
inline ~BytecodeBlock() { // Do backpatch when block goes out
// of scope...
if (Loc == Out.size() && ElideIfEmpty) {
// If the block is empty, and we are allowed to, do not emit the block at
// all!
Out.resize(Out.size()-8);
return;
}
//cerr << "OldLoc = " << Loc << " NewLoc = " << NewLoc << " diff = "
// << (NewLoc-Loc) << endl;
output(unsigned(Out.size()-Loc), Out, int(Loc-4));
align32(Out); // Blocks must ALWAYS be aligned
}
inline ~BytecodeBlock();
};
} // End llvm namespace

141
lib/Bytecode/Writer/WriterPrimitives.h
View File

@ -1,141 +0,0 @@
//===-- WriterPrimitives.h - Bytecode writer file format prims --*- C++ -*-===//
//
// 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 header defines some basic functions for writing basic primitive types to
// a bytecode stream.
//
//===----------------------------------------------------------------------===//
#ifndef WRITERPRIMITIVES_H
#define WRITERPRIMITIVES_H
#include "Support/DataTypes.h"
#include <string>
#include <deque>
namespace llvm {
// 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...
//
static inline void output(unsigned i, std::deque<unsigned char> &Out,
int pos = -1) {
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);
}
}
static inline void output(int i, std::deque<unsigned char> &Out) {
output((unsigned)i, Out);
}
// 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 night 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...
//
static inline void output_vbr(uint64_t i, std::deque<unsigned char> &out) {
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...
}
}
static inline void output_vbr(unsigned i, std::deque<unsigned char> &out) {
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...
}
}
static inline void output_vbr(int64_t i, std::deque<unsigned char> &out) {
if (i < 0)
output_vbr(((uint64_t)(-i) << 1) | 1, out); // Set low order sign bit...
else
output_vbr((uint64_t)i << 1, out); // Low order bit is clear.
}
static inline void output_vbr(int i, std::deque<unsigned char> &out) {
if (i < 0)
output_vbr(((unsigned)(-i) << 1) | 1, out); // Set low order sign bit...
else
output_vbr((unsigned)i << 1, out); // Low order bit is clear.
}
// align32 - emit the minimal number of bytes that will bring us to 32 bit
// alignment...
//
static inline void align32(std::deque<unsigned char> &Out) {
int NumPads = (4-(Out.size() & 3)) & 3; // Bytes to get padding to 32 bits
while (NumPads--) Out.push_back((unsigned char)0xAB);
}
static inline void output(const std::string &s, std::deque<unsigned char> &Out,
bool Aligned = true) {
unsigned Len = s.length();
output_vbr(Len, Out); // Strings may have an arbitrary length...
Out.insert(Out.end(), s.begin(), s.end());
if (Aligned)
align32(Out); // Make sure we are now aligned...
}
static inline void output_data(const void *Ptr, const void *End,
std::deque<unsigned char> &Out) {
Out.insert(Out.end(), (const unsigned char*)Ptr, (const unsigned char*)End);
}
static inline void output_float(float& FloatVal,
std::deque<unsigned char>& Out) {
/// FIXME: This is a broken implementation! It writes
/// it in a platform-specific endianess. Need to make
/// it little endian always.
output_data(&FloatVal, &FloatVal+1, Out);
}
static inline void output_double(double& DoubleVal,
std::deque<unsigned char>& Out) {
/// FIXME: This is a broken implementation! It writes
/// it in a platform-specific endianess. Need to make
/// it little endian always.
output_data(&DoubleVal, &DoubleVal+1, Out);
}
} // End llvm namespace
// vim: sw=2 ai
#endif