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llvm-project/llvm/lib/ExecutionEngine/ExecutionEngine.cpp

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//===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the common interface used by the various execution engine
// subclasses.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "jit"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Config/alloca.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MutexGuard.h"
#include "llvm/System/DynamicLibrary.h"
#include "llvm/System/Host.h"
#include "llvm/Target/TargetData.h"
#include <cmath>
#include <cstring>
using namespace llvm;
STATISTIC(NumInitBytes, "Number of bytes of global vars initialized");
STATISTIC(NumGlobals , "Number of global vars initialized");
ExecutionEngine::EECtorFn ExecutionEngine::JITCtor = 0;
ExecutionEngine::EECtorFn ExecutionEngine::InterpCtor = 0;
ExecutionEngine::EERegisterFn ExecutionEngine::ExceptionTableRegister = 0;
ExecutionEngine::ExecutionEngine(ModuleProvider *P) : LazyFunctionCreator(0) {
LazyCompilationDisabled = false;
Modules.push_back(P);
assert(P && "ModuleProvider is null?");
}
ExecutionEngine::~ExecutionEngine() {
clearAllGlobalMappings();
for (unsigned i = 0, e = Modules.size(); i != e; ++i)
delete Modules[i];
}
/// removeModuleProvider - Remove a ModuleProvider from the list of modules.
/// Release module from ModuleProvider.
Module* ExecutionEngine::removeModuleProvider(ModuleProvider *P,
std::string *ErrInfo) {
for(SmallVector<ModuleProvider *, 1>::iterator I = Modules.begin(),
E = Modules.end(); I != E; ++I) {
ModuleProvider *MP = *I;
if (MP == P) {
Modules.erase(I);
return MP->releaseModule(ErrInfo);
}
}
return NULL;
}
/// FindFunctionNamed - Search all of the active modules to find the one that
/// defines FnName. This is very slow operation and shouldn't be used for
/// general code.
Function *ExecutionEngine::FindFunctionNamed(const char *FnName) {
for (unsigned i = 0, e = Modules.size(); i != e; ++i) {
if (Function *F = Modules[i]->getModule()->getFunction(FnName))
return F;
}
return 0;
}
/// addGlobalMapping - Tell the execution engine that the specified global is
/// at the specified location. This is used internally as functions are JIT'd
/// and as global variables are laid out in memory. It can and should also be
/// used by clients of the EE that want to have an LLVM global overlay
/// existing data in memory.
void ExecutionEngine::addGlobalMapping(const GlobalValue *GV, void *Addr) {
MutexGuard locked(lock);
void *&CurVal = state.getGlobalAddressMap(locked)[GV];
assert((CurVal == 0 || Addr == 0) && "GlobalMapping already established!");
CurVal = Addr;
// If we are using the reverse mapping, add it too
if (!state.getGlobalAddressReverseMap(locked).empty()) {
const GlobalValue *&V = state.getGlobalAddressReverseMap(locked)[Addr];
assert((V == 0 || GV == 0) && "GlobalMapping already established!");
V = GV;
}
}
/// clearAllGlobalMappings - Clear all global mappings and start over again
/// use in dynamic compilation scenarios when you want to move globals
void ExecutionEngine::clearAllGlobalMappings() {
MutexGuard locked(lock);
state.getGlobalAddressMap(locked).clear();
state.getGlobalAddressReverseMap(locked).clear();
}
/// updateGlobalMapping - Replace an existing mapping for GV with a new
/// address. This updates both maps as required. If "Addr" is null, the
/// entry for the global is removed from the mappings.
void *ExecutionEngine::updateGlobalMapping(const GlobalValue *GV, void *Addr) {
MutexGuard locked(lock);
std::map<const GlobalValue*, void *> &Map = state.getGlobalAddressMap(locked);
// Deleting from the mapping?
if (Addr == 0) {
std::map<const GlobalValue*, void *>::iterator I = Map.find(GV);
void *OldVal;
if (I == Map.end())
OldVal = 0;
else {
OldVal = I->second;
Map.erase(I);
}
if (!state.getGlobalAddressReverseMap(locked).empty())
state.getGlobalAddressReverseMap(locked).erase(Addr);
return OldVal;
}
void *&CurVal = Map[GV];
void *OldVal = CurVal;
if (CurVal && !state.getGlobalAddressReverseMap(locked).empty())
state.getGlobalAddressReverseMap(locked).erase(CurVal);
CurVal = Addr;
// If we are using the reverse mapping, add it too
if (!state.getGlobalAddressReverseMap(locked).empty()) {
const GlobalValue *&V = state.getGlobalAddressReverseMap(locked)[Addr];
assert((V == 0 || GV == 0) && "GlobalMapping already established!");
V = GV;
}
return OldVal;
}
/// getPointerToGlobalIfAvailable - This returns the address of the specified
/// global value if it is has already been codegen'd, otherwise it returns null.
///
void *ExecutionEngine::getPointerToGlobalIfAvailable(const GlobalValue *GV) {
MutexGuard locked(lock);
std::map<const GlobalValue*, void*>::iterator I =
state.getGlobalAddressMap(locked).find(GV);
return I != state.getGlobalAddressMap(locked).end() ? I->second : 0;
}
/// getGlobalValueAtAddress - Return the LLVM global value object that starts
/// at the specified address.
///
const GlobalValue *ExecutionEngine::getGlobalValueAtAddress(void *Addr) {
MutexGuard locked(lock);
// If we haven't computed the reverse mapping yet, do so first.
if (state.getGlobalAddressReverseMap(locked).empty()) {
for (std::map<const GlobalValue*, void *>::iterator
I = state.getGlobalAddressMap(locked).begin(),
E = state.getGlobalAddressMap(locked).end(); I != E; ++I)
state.getGlobalAddressReverseMap(locked).insert(std::make_pair(I->second,
I->first));
}
std::map<void *, const GlobalValue*>::iterator I =
state.getGlobalAddressReverseMap(locked).find(Addr);
return I != state.getGlobalAddressReverseMap(locked).end() ? I->second : 0;
}
// CreateArgv - Turn a vector of strings into a nice argv style array of
// pointers to null terminated strings.
//
static void *CreateArgv(ExecutionEngine *EE,
const std::vector<std::string> &InputArgv) {
unsigned PtrSize = EE->getTargetData()->getPointerSize();
char *Result = new char[(InputArgv.size()+1)*PtrSize];
DOUT << "ARGV = " << (void*)Result << "\n";
const Type *SBytePtr = PointerType::getUnqual(Type::Int8Ty);
for (unsigned i = 0; i != InputArgv.size(); ++i) {
unsigned Size = InputArgv[i].size()+1;
char *Dest = new char[Size];
DOUT << "ARGV[" << i << "] = " << (void*)Dest << "\n";
std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest);
Dest[Size-1] = 0;
// Endian safe: Result[i] = (PointerTy)Dest;
EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i*PtrSize),
SBytePtr);
}
// Null terminate it
EE->StoreValueToMemory(PTOGV(0),
(GenericValue*)(Result+InputArgv.size()*PtrSize),
SBytePtr);
return Result;
}
/// runStaticConstructorsDestructors - This method is used to execute all of
/// the static constructors or destructors for a program, depending on the
/// value of isDtors.
void ExecutionEngine::runStaticConstructorsDestructors(bool isDtors) {
const char *Name = isDtors ? "llvm.global_dtors" : "llvm.global_ctors";
// Execute global ctors/dtors for each module in the program.
for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
GlobalVariable *GV = Modules[m]->getModule()->getNamedGlobal(Name);
// If this global has internal linkage, or if it has a use, then it must be
// an old-style (llvmgcc3) static ctor with __main linked in and in use. If
// this is the case, don't execute any of the global ctors, __main will do
// it.
if (!GV || GV->isDeclaration() || GV->hasInternalLinkage()) continue;
// Should be an array of '{ int, void ()* }' structs. The first value is
// the init priority, which we ignore.
ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
if (!InitList) continue;
for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
if (ConstantStruct *CS =
dyn_cast<ConstantStruct>(InitList->getOperand(i))) {
if (CS->getNumOperands() != 2) break; // Not array of 2-element structs.
Constant *FP = CS->getOperand(1);
if (FP->isNullValue())
break; // Found a null terminator, exit.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(FP))
if (CE->isCast())
FP = CE->getOperand(0);
if (Function *F = dyn_cast<Function>(FP)) {
// Execute the ctor/dtor function!
runFunction(F, std::vector<GenericValue>());
}
}
}
}
/// isTargetNullPtr - Return whether the target pointer stored at Loc is null.
static bool isTargetNullPtr(ExecutionEngine *EE, void *Loc) {
unsigned PtrSize = EE->getTargetData()->getPointerSize();
for (unsigned i = 0; i < PtrSize; ++i)
if (*(i + (uint8_t*)Loc))
return false;
return true;
}
/// runFunctionAsMain - This is a helper function which wraps runFunction to
/// handle the common task of starting up main with the specified argc, argv,
/// and envp parameters.
int ExecutionEngine::runFunctionAsMain(Function *Fn,
const std::vector<std::string> &argv,
const char * const * envp) {
std::vector<GenericValue> GVArgs;
GenericValue GVArgc;
GVArgc.IntVal = APInt(32, argv.size());
// Check main() type
unsigned NumArgs = Fn->getFunctionType()->getNumParams();
const FunctionType *FTy = Fn->getFunctionType();
const Type* PPInt8Ty =
PointerType::getUnqual(PointerType::getUnqual(Type::Int8Ty));
switch (NumArgs) {
case 3:
if (FTy->getParamType(2) != PPInt8Ty) {
cerr << "Invalid type for third argument of main() supplied\n";
abort();
}
// FALLS THROUGH
case 2:
if (FTy->getParamType(1) != PPInt8Ty) {
cerr << "Invalid type for second argument of main() supplied\n";
abort();
}
// FALLS THROUGH
case 1:
if (FTy->getParamType(0) != Type::Int32Ty) {
cerr << "Invalid type for first argument of main() supplied\n";
abort();
}
// FALLS THROUGH
case 0:
if (FTy->getReturnType() != Type::Int32Ty &&
FTy->getReturnType() != Type::VoidTy) {
cerr << "Invalid return type of main() supplied\n";
abort();
}
break;
default:
cerr << "Invalid number of arguments of main() supplied\n";
abort();
}
if (NumArgs) {
GVArgs.push_back(GVArgc); // Arg #0 = argc.
if (NumArgs > 1) {
GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv.
assert(!isTargetNullPtr(this, GVTOP(GVArgs[1])) &&
"argv[0] was null after CreateArgv");
if (NumArgs > 2) {
std::vector<std::string> EnvVars;
for (unsigned i = 0; envp[i]; ++i)
EnvVars.push_back(envp[i]);
GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp.
}
}
}
return runFunction(Fn, GVArgs).IntVal.getZExtValue();
}
/// If possible, create a JIT, unless the caller specifically requests an
/// Interpreter or there's an error. If even an Interpreter cannot be created,
/// NULL is returned.
///
ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
bool ForceInterpreter,
std::string *ErrorStr) {
ExecutionEngine *EE = 0;
// Make sure we can resolve symbols in the program as well. The zero arg
// to the function tells DynamicLibrary to load the program, not a library.
if (sys::DynamicLibrary::LoadLibraryPermanently(0, ErrorStr))
return 0;
// Unless the interpreter was explicitly selected, try making a JIT.
if (!ForceInterpreter && JITCtor)
EE = JITCtor(MP, ErrorStr);
// If we can't make a JIT, make an interpreter instead.
if (EE == 0 && InterpCtor)
EE = InterpCtor(MP, ErrorStr);
return EE;
}
ExecutionEngine *ExecutionEngine::create(Module *M) {
return create(new ExistingModuleProvider(M));
}
/// getPointerToGlobal - This returns the address of the specified global
/// value. This may involve code generation if it's a function.
///
void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) {
if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV)))
return getPointerToFunction(F);
MutexGuard locked(lock);
void *p = state.getGlobalAddressMap(locked)[GV];
if (p)
return p;
// Global variable might have been added since interpreter started.
if (GlobalVariable *GVar =
const_cast<GlobalVariable *>(dyn_cast<GlobalVariable>(GV)))
EmitGlobalVariable(GVar);
else
assert(0 && "Global hasn't had an address allocated yet!");
return state.getGlobalAddressMap(locked)[GV];
}
/// This function converts a Constant* into a GenericValue. The interesting
/// part is if C is a ConstantExpr.
/// @brief Get a GenericValue for a Constant*
GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
// If its undefined, return the garbage.
if (isa<UndefValue>(C))
return GenericValue();
// If the value is a ConstantExpr
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
Constant *Op0 = CE->getOperand(0);
switch (CE->getOpcode()) {
case Instruction::GetElementPtr: {
// Compute the index
GenericValue Result = getConstantValue(Op0);
SmallVector<Value*, 8> Indices(CE->op_begin()+1, CE->op_end());
uint64_t Offset =
TD->getIndexedOffset(Op0->getType(), &Indices[0], Indices.size());
char* tmp = (char*) Result.PointerVal;
Result = PTOGV(tmp + Offset);
return Result;
}
case Instruction::Trunc: {
GenericValue GV = getConstantValue(Op0);
uint32_t BitWidth = cast<IntegerType>(CE->getType())->getBitWidth();
GV.IntVal = GV.IntVal.trunc(BitWidth);
return GV;
}
case Instruction::ZExt: {
GenericValue GV = getConstantValue(Op0);
uint32_t BitWidth = cast<IntegerType>(CE->getType())->getBitWidth();
GV.IntVal = GV.IntVal.zext(BitWidth);
return GV;
}
case Instruction::SExt: {
GenericValue GV = getConstantValue(Op0);
uint32_t BitWidth = cast<IntegerType>(CE->getType())->getBitWidth();
GV.IntVal = GV.IntVal.sext(BitWidth);
return GV;
}
case Instruction::FPTrunc: {
// FIXME long double
GenericValue GV = getConstantValue(Op0);
GV.FloatVal = float(GV.DoubleVal);
return GV;
}
case Instruction::FPExt:{
// FIXME long double
GenericValue GV = getConstantValue(Op0);
GV.DoubleVal = double(GV.FloatVal);
return GV;
}
case Instruction::UIToFP: {
GenericValue GV = getConstantValue(Op0);
if (CE->getType() == Type::FloatTy)
GV.FloatVal = float(GV.IntVal.roundToDouble());
else if (CE->getType() == Type::DoubleTy)
GV.DoubleVal = GV.IntVal.roundToDouble();
else if (CE->getType() == Type::X86_FP80Ty) {
const uint64_t zero[] = {0, 0};
APFloat apf = APFloat(APInt(80, 2, zero));
(void)apf.convertFromAPInt(GV.IntVal,
false,
APFloat::rmNearestTiesToEven);
GV.IntVal = apf.convertToAPInt();
}
return GV;
}
case Instruction::SIToFP: {
GenericValue GV = getConstantValue(Op0);
if (CE->getType() == Type::FloatTy)
GV.FloatVal = float(GV.IntVal.signedRoundToDouble());
else if (CE->getType() == Type::DoubleTy)
GV.DoubleVal = GV.IntVal.signedRoundToDouble();
else if (CE->getType() == Type::X86_FP80Ty) {
const uint64_t zero[] = { 0, 0};
APFloat apf = APFloat(APInt(80, 2, zero));
(void)apf.convertFromAPInt(GV.IntVal,
true,
APFloat::rmNearestTiesToEven);
GV.IntVal = apf.convertToAPInt();
}
return GV;
}
case Instruction::FPToUI: // double->APInt conversion handles sign
case Instruction::FPToSI: {
GenericValue GV = getConstantValue(Op0);
uint32_t BitWidth = cast<IntegerType>(CE->getType())->getBitWidth();
if (Op0->getType() == Type::FloatTy)
GV.IntVal = APIntOps::RoundFloatToAPInt(GV.FloatVal, BitWidth);
else if (Op0->getType() == Type::DoubleTy)
GV.IntVal = APIntOps::RoundDoubleToAPInt(GV.DoubleVal, BitWidth);
else if (Op0->getType() == Type::X86_FP80Ty) {
APFloat apf = APFloat(GV.IntVal);
uint64_t v;
(void)apf.convertToInteger(&v, BitWidth,
CE->getOpcode()==Instruction::FPToSI,
APFloat::rmTowardZero);
GV.IntVal = v; // endian?
}
return GV;
}
case Instruction::PtrToInt: {
GenericValue GV = getConstantValue(Op0);
uint32_t PtrWidth = TD->getPointerSizeInBits();
GV.IntVal = APInt(PtrWidth, uintptr_t(GV.PointerVal));
return GV;
}
case Instruction::IntToPtr: {
GenericValue GV = getConstantValue(Op0);
uint32_t PtrWidth = TD->getPointerSizeInBits();
if (PtrWidth != GV.IntVal.getBitWidth())
GV.IntVal = GV.IntVal.zextOrTrunc(PtrWidth);
assert(GV.IntVal.getBitWidth() <= 64 && "Bad pointer width");
GV.PointerVal = PointerTy(uintptr_t(GV.IntVal.getZExtValue()));
return GV;
}
case Instruction::BitCast: {
GenericValue GV = getConstantValue(Op0);
const Type* DestTy = CE->getType();
switch (Op0->getType()->getTypeID()) {
default: assert(0 && "Invalid bitcast operand");
case Type::IntegerTyID:
assert(DestTy->isFloatingPoint() && "invalid bitcast");
if (DestTy == Type::FloatTy)
GV.FloatVal = GV.IntVal.bitsToFloat();
else if (DestTy == Type::DoubleTy)
GV.DoubleVal = GV.IntVal.bitsToDouble();
break;
case Type::FloatTyID:
assert(DestTy == Type::Int32Ty && "Invalid bitcast");
GV.IntVal.floatToBits(GV.FloatVal);
break;
case Type::DoubleTyID:
assert(DestTy == Type::Int64Ty && "Invalid bitcast");
GV.IntVal.doubleToBits(GV.DoubleVal);
break;
case Type::PointerTyID:
assert(isa<PointerType>(DestTy) && "Invalid bitcast");
break; // getConstantValue(Op0) above already converted it
}
return GV;
}
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
GenericValue LHS = getConstantValue(Op0);
GenericValue RHS = getConstantValue(CE->getOperand(1));
GenericValue GV;
switch (CE->getOperand(0)->getType()->getTypeID()) {
default: assert(0 && "Bad add type!"); abort();
case Type::IntegerTyID:
switch (CE->getOpcode()) {
default: assert(0 && "Invalid integer opcode");
case Instruction::Add: GV.IntVal = LHS.IntVal + RHS.IntVal; break;
case Instruction::Sub: GV.IntVal = LHS.IntVal - RHS.IntVal; break;
case Instruction::Mul: GV.IntVal = LHS.IntVal * RHS.IntVal; break;
case Instruction::UDiv:GV.IntVal = LHS.IntVal.udiv(RHS.IntVal); break;
case Instruction::SDiv:GV.IntVal = LHS.IntVal.sdiv(RHS.IntVal); break;
case Instruction::URem:GV.IntVal = LHS.IntVal.urem(RHS.IntVal); break;
case Instruction::SRem:GV.IntVal = LHS.IntVal.srem(RHS.IntVal); break;
case Instruction::And: GV.IntVal = LHS.IntVal & RHS.IntVal; break;
case Instruction::Or: GV.IntVal = LHS.IntVal | RHS.IntVal; break;
case Instruction::Xor: GV.IntVal = LHS.IntVal ^ RHS.IntVal; break;
}
break;
case Type::FloatTyID:
switch (CE->getOpcode()) {
default: assert(0 && "Invalid float opcode"); abort();
case Instruction::Add:
GV.FloatVal = LHS.FloatVal + RHS.FloatVal; break;
case Instruction::Sub:
GV.FloatVal = LHS.FloatVal - RHS.FloatVal; break;
case Instruction::Mul:
GV.FloatVal = LHS.FloatVal * RHS.FloatVal; break;
case Instruction::FDiv:
GV.FloatVal = LHS.FloatVal / RHS.FloatVal; break;
case Instruction::FRem:
GV.FloatVal = ::fmodf(LHS.FloatVal,RHS.FloatVal); break;
}
break;
case Type::DoubleTyID:
switch (CE->getOpcode()) {
default: assert(0 && "Invalid double opcode"); abort();
case Instruction::Add:
GV.DoubleVal = LHS.DoubleVal + RHS.DoubleVal; break;
case Instruction::Sub:
GV.DoubleVal = LHS.DoubleVal - RHS.DoubleVal; break;
case Instruction::Mul:
GV.DoubleVal = LHS.DoubleVal * RHS.DoubleVal; break;
case Instruction::FDiv:
GV.DoubleVal = LHS.DoubleVal / RHS.DoubleVal; break;
case Instruction::FRem:
GV.DoubleVal = ::fmod(LHS.DoubleVal,RHS.DoubleVal); break;
}
break;
case Type::X86_FP80TyID:
case Type::PPC_FP128TyID:
case Type::FP128TyID: {
APFloat apfLHS = APFloat(LHS.IntVal);
switch (CE->getOpcode()) {
default: assert(0 && "Invalid long double opcode"); abort();
case Instruction::Add:
apfLHS.add(APFloat(RHS.IntVal), APFloat::rmNearestTiesToEven);
GV.IntVal = apfLHS.convertToAPInt();
break;
case Instruction::Sub:
apfLHS.subtract(APFloat(RHS.IntVal), APFloat::rmNearestTiesToEven);
GV.IntVal = apfLHS.convertToAPInt();
break;
case Instruction::Mul:
apfLHS.multiply(APFloat(RHS.IntVal), APFloat::rmNearestTiesToEven);
GV.IntVal = apfLHS.convertToAPInt();
break;
case Instruction::FDiv:
apfLHS.divide(APFloat(RHS.IntVal), APFloat::rmNearestTiesToEven);
GV.IntVal = apfLHS.convertToAPInt();
break;
case Instruction::FRem:
apfLHS.mod(APFloat(RHS.IntVal), APFloat::rmNearestTiesToEven);
GV.IntVal = apfLHS.convertToAPInt();
break;
}
}
break;
}
return GV;
}
default:
break;
}
cerr << "ConstantExpr not handled: " << *CE << "\n";
abort();
}
GenericValue Result;
switch (C->getType()->getTypeID()) {
case Type::FloatTyID:
Result.FloatVal = cast<ConstantFP>(C)->getValueAPF().convertToFloat();
break;
case Type::DoubleTyID:
Result.DoubleVal = cast<ConstantFP>(C)->getValueAPF().convertToDouble();
break;
case Type::X86_FP80TyID:
case Type::FP128TyID:
case Type::PPC_FP128TyID:
Result.IntVal = cast <ConstantFP>(C)->getValueAPF().convertToAPInt();
break;
case Type::IntegerTyID:
Result.IntVal = cast<ConstantInt>(C)->getValue();
break;
case Type::PointerTyID:
if (isa<ConstantPointerNull>(C))
Result.PointerVal = 0;
else if (const Function *F = dyn_cast<Function>(C))
Result = PTOGV(getPointerToFunctionOrStub(const_cast<Function*>(F)));
else if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C))
Result = PTOGV(getOrEmitGlobalVariable(const_cast<GlobalVariable*>(GV)));
else
assert(0 && "Unknown constant pointer type!");
break;
default:
cerr << "ERROR: Constant unimplemented for type: " << *C->getType() << "\n";
abort();
}
return Result;
}
/// StoreIntToMemory - Fills the StoreBytes bytes of memory starting from Dst
/// with the integer held in IntVal.
static void StoreIntToMemory(const APInt &IntVal, uint8_t *Dst,
unsigned StoreBytes) {
assert((IntVal.getBitWidth()+7)/8 >= StoreBytes && "Integer too small!");
uint8_t *Src = (uint8_t *)IntVal.getRawData();
if (sys::littleEndianHost())
// Little-endian host - the source is ordered from LSB to MSB. Order the
// destination from LSB to MSB: Do a straight copy.
memcpy(Dst, Src, StoreBytes);
else {
// Big-endian host - the source is an array of 64 bit words ordered from
// LSW to MSW. Each word is ordered from MSB to LSB. Order the destination
// from MSB to LSB: Reverse the word order, but not the bytes in a word.
while (StoreBytes > sizeof(uint64_t)) {
StoreBytes -= sizeof(uint64_t);
// May not be aligned so use memcpy.
memcpy(Dst + StoreBytes, Src, sizeof(uint64_t));
Src += sizeof(uint64_t);
}
memcpy(Dst, Src + sizeof(uint64_t) - StoreBytes, StoreBytes);
}
}
/// StoreValueToMemory - Stores the data in Val of type Ty at address Ptr. Ptr
/// is the address of the memory at which to store Val, cast to GenericValue *.
/// It is not a pointer to a GenericValue containing the address at which to
/// store Val.
void ExecutionEngine::StoreValueToMemory(const GenericValue &Val, GenericValue *Ptr,
const Type *Ty) {
const unsigned StoreBytes = getTargetData()->getTypeStoreSize(Ty);
switch (Ty->getTypeID()) {
case Type::IntegerTyID:
StoreIntToMemory(Val.IntVal, (uint8_t*)Ptr, StoreBytes);
break;
case Type::FloatTyID:
*((float*)Ptr) = Val.FloatVal;
break;
case Type::DoubleTyID:
*((double*)Ptr) = Val.DoubleVal;
break;
case Type::X86_FP80TyID: {
uint16_t *Dest = (uint16_t*)Ptr;
const uint16_t *Src = (uint16_t*)Val.IntVal.getRawData();
// This is endian dependent, but it will only work on x86 anyway.
Dest[0] = Src[4];
Dest[1] = Src[0];
Dest[2] = Src[1];
Dest[3] = Src[2];
Dest[4] = Src[3];
break;
}
case Type::PointerTyID:
// Ensure 64 bit target pointers are fully initialized on 32 bit hosts.
if (StoreBytes != sizeof(PointerTy))
memset(Ptr, 0, StoreBytes);
*((PointerTy*)Ptr) = Val.PointerVal;
break;
default:
cerr << "Cannot store value of type " << *Ty << "!\n";
}
if (sys::littleEndianHost() != getTargetData()->isLittleEndian())
// Host and target are different endian - reverse the stored bytes.
std::reverse((uint8_t*)Ptr, StoreBytes + (uint8_t*)Ptr);
}
/// LoadIntFromMemory - Loads the integer stored in the LoadBytes bytes starting
/// from Src into IntVal, which is assumed to be wide enough and to hold zero.
static void LoadIntFromMemory(APInt &IntVal, uint8_t *Src, unsigned LoadBytes) {
assert((IntVal.getBitWidth()+7)/8 >= LoadBytes && "Integer too small!");
uint8_t *Dst = (uint8_t *)IntVal.getRawData();
if (sys::littleEndianHost())
// Little-endian host - the destination must be ordered from LSB to MSB.
// The source is ordered from LSB to MSB: Do a straight copy.
memcpy(Dst, Src, LoadBytes);
else {
// Big-endian - the destination is an array of 64 bit words ordered from
// LSW to MSW. Each word must be ordered from MSB to LSB. The source is
// ordered from MSB to LSB: Reverse the word order, but not the bytes in
// a word.
while (LoadBytes > sizeof(uint64_t)) {
LoadBytes -= sizeof(uint64_t);
// May not be aligned so use memcpy.
memcpy(Dst, Src + LoadBytes, sizeof(uint64_t));
Dst += sizeof(uint64_t);
}
memcpy(Dst + sizeof(uint64_t) - LoadBytes, Src, LoadBytes);
}
}
/// FIXME: document
///
void ExecutionEngine::LoadValueFromMemory(GenericValue &Result,
GenericValue *Ptr,
const Type *Ty) {
const unsigned LoadBytes = getTargetData()->getTypeStoreSize(Ty);
if (sys::littleEndianHost() != getTargetData()->isLittleEndian()) {
// Host and target are different endian - reverse copy the stored
// bytes into a buffer, and load from that.
uint8_t *Src = (uint8_t*)Ptr;
uint8_t *Buf = (uint8_t*)alloca(LoadBytes);
std::reverse_copy(Src, Src + LoadBytes, Buf);
Ptr = (GenericValue*)Buf;
}
switch (Ty->getTypeID()) {
case Type::IntegerTyID:
// An APInt with all words initially zero.
Result.IntVal = APInt(cast<IntegerType>(Ty)->getBitWidth(), 0);
LoadIntFromMemory(Result.IntVal, (uint8_t*)Ptr, LoadBytes);
break;
case Type::FloatTyID:
Result.FloatVal = *((float*)Ptr);
break;
case Type::DoubleTyID:
Result.DoubleVal = *((double*)Ptr);
break;
case Type::PointerTyID:
Result.PointerVal = *((PointerTy*)Ptr);
break;
case Type::X86_FP80TyID: {
// This is endian dependent, but it will only work on x86 anyway.
// FIXME: Will not trap if loading a signaling NaN.
uint16_t *p = (uint16_t*)Ptr;
union {
uint16_t x[8];
uint64_t y[2];
};
x[0] = p[1];
x[1] = p[2];
x[2] = p[3];
x[3] = p[4];
x[4] = p[0];
Result.IntVal = APInt(80, 2, y);
break;
}
default:
cerr << "Cannot load value of type " << *Ty << "!\n";
abort();
}
}
// InitializeMemory - Recursive function to apply a Constant value into the
// specified memory location...
//
void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) {
if (isa<UndefValue>(Init)) {
return;
} else if (const ConstantVector *CP = dyn_cast<ConstantVector>(Init)) {
unsigned ElementSize =
getTargetData()->getABITypeSize(CP->getType()->getElementType());
for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
InitializeMemory(CP->getOperand(i), (char*)Addr+i*ElementSize);
return;
} else if (isa<ConstantAggregateZero>(Init)) {
memset(Addr, 0, (size_t)getTargetData()->getABITypeSize(Init->getType()));
return;
} else if (Init->getType()->isFirstClassType()) {
GenericValue Val = getConstantValue(Init);
StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
return;
}
switch (Init->getType()->getTypeID()) {
case Type::ArrayTyID: {
const ConstantArray *CPA = cast<ConstantArray>(Init);
unsigned ElementSize =
getTargetData()->getABITypeSize(CPA->getType()->getElementType());
for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i)
InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize);
return;
}
case Type::StructTyID: {
const ConstantStruct *CPS = cast<ConstantStruct>(Init);
const StructLayout *SL =
getTargetData()->getStructLayout(cast<StructType>(CPS->getType()));
for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i)
InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->getElementOffset(i));
return;
}
default:
cerr << "Bad Type: " << *Init->getType() << "\n";
assert(0 && "Unknown constant type to initialize memory with!");
}
}
/// EmitGlobals - Emit all of the global variables to memory, storing their
/// addresses into GlobalAddress. This must make sure to copy the contents of
/// their initializers into the memory.
///
void ExecutionEngine::emitGlobals() {
const TargetData *TD = getTargetData();
// Loop over all of the global variables in the program, allocating the memory
// to hold them. If there is more than one module, do a prepass over globals
// to figure out how the different modules should link together.
//
std::map<std::pair<std::string, const Type*>,
const GlobalValue*> LinkedGlobalsMap;
if (Modules.size() != 1) {
for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
Module &M = *Modules[m]->getModule();
for (Module::const_global_iterator I = M.global_begin(),
E = M.global_end(); I != E; ++I) {
const GlobalValue *GV = I;
if (GV->hasInternalLinkage() || GV->isDeclaration() ||
GV->hasAppendingLinkage() || !GV->hasName())
continue;// Ignore external globals and globals with internal linkage.
const GlobalValue *&GVEntry =
LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())];
// If this is the first time we've seen this global, it is the canonical
// version.
if (!GVEntry) {
GVEntry = GV;
continue;
}
// If the existing global is strong, never replace it.
if (GVEntry->hasExternalLinkage() ||
GVEntry->hasDLLImportLinkage() ||
GVEntry->hasDLLExportLinkage())
continue;
// Otherwise, we know it's linkonce/weak, replace it if this is a strong
// symbol.
if (GV->hasExternalLinkage() || GVEntry->hasExternalWeakLinkage())
GVEntry = GV;
}
}
}
std::vector<const GlobalValue*> NonCanonicalGlobals;
for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
Module &M = *Modules[m]->getModule();
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
// In the multi-module case, see what this global maps to.
if (!LinkedGlobalsMap.empty()) {
if (const GlobalValue *GVEntry =
LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())]) {
// If something else is the canonical global, ignore this one.
if (GVEntry != &*I) {
NonCanonicalGlobals.push_back(I);
continue;
}
}
}
if (!I->isDeclaration()) {
// Get the type of the global.
const Type *Ty = I->getType()->getElementType();
// Allocate some memory for it!
unsigned Size = TD->getABITypeSize(Ty);
addGlobalMapping(I, new char[Size]);
} else {
// External variable reference. Try to use the dynamic loader to
// get a pointer to it.
if (void *SymAddr =
sys::DynamicLibrary::SearchForAddressOfSymbol(I->getName().c_str()))
addGlobalMapping(I, SymAddr);
else {
cerr << "Could not resolve external global address: "
<< I->getName() << "\n";
abort();
}
}
}
// If there are multiple modules, map the non-canonical globals to their
// canonical location.
if (!NonCanonicalGlobals.empty()) {
for (unsigned i = 0, e = NonCanonicalGlobals.size(); i != e; ++i) {
const GlobalValue *GV = NonCanonicalGlobals[i];
const GlobalValue *CGV =
LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())];
void *Ptr = getPointerToGlobalIfAvailable(CGV);
assert(Ptr && "Canonical global wasn't codegen'd!");
addGlobalMapping(GV, getPointerToGlobalIfAvailable(CGV));
}
}
// Now that all of the globals are set up in memory, loop through them all
// and initialize their contents.
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
if (!I->isDeclaration()) {
if (!LinkedGlobalsMap.empty()) {
if (const GlobalValue *GVEntry =
LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())])
if (GVEntry != &*I) // Not the canonical variable.
continue;
}
EmitGlobalVariable(I);
}
}
}
}
// EmitGlobalVariable - This method emits the specified global variable to the
// address specified in GlobalAddresses, or allocates new memory if it's not
// already in the map.
void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) {
void *GA = getPointerToGlobalIfAvailable(GV);
DOUT << "Global '" << GV->getName() << "' -> " << GA << "\n";
const Type *ElTy = GV->getType()->getElementType();
size_t GVSize = (size_t)getTargetData()->getABITypeSize(ElTy);
if (GA == 0) {
// If it's not already specified, allocate memory for the global.
GA = new char[GVSize];
addGlobalMapping(GV, GA);
}
InitializeMemory(GV->getInitializer(), GA);
NumInitBytes += (unsigned)GVSize;
++NumGlobals;
}
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