1 //===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the common interface used by the various execution engine
13 //===----------------------------------------------------------------------===//
15 #define DEBUG_TYPE "jit"
16 #include "llvm/Constants.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Module.h"
19 #include "llvm/ModuleProvider.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/ExecutionEngine/ExecutionEngine.h"
22 #include "llvm/ExecutionEngine/GenericValue.h"
23 #include "llvm/Support/Debug.h"
24 #include "llvm/Support/MutexGuard.h"
25 #include "llvm/System/DynamicLibrary.h"
26 #include "llvm/Target/TargetData.h"
31 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized");
32 Statistic<> NumGlobals ("lli", "Number of global vars initialized");
35 ExecutionEngine::EECtorFn ExecutionEngine::JITCtor = 0;
36 ExecutionEngine::EECtorFn ExecutionEngine::InterpCtor = 0;
38 ExecutionEngine::ExecutionEngine(ModuleProvider *P) {
39 LazyCompilationDisabled = false;
41 assert(P && "ModuleProvider is null?");
44 ExecutionEngine::ExecutionEngine(Module *M) {
45 LazyCompilationDisabled = false;
46 assert(M && "Module is null?");
47 Modules.push_back(new ExistingModuleProvider(M));
50 ExecutionEngine::~ExecutionEngine() {
51 for (unsigned i = 0, e = Modules.size(); i != e; ++i)
55 /// FindFunctionNamed - Search all of the active modules to find the one that
56 /// defines FnName. This is very slow operation and shouldn't be used for
58 Function *ExecutionEngine::FindFunctionNamed(const char *FnName) {
59 for (unsigned i = 0, e = Modules.size(); i != e; ++i) {
60 if (Function *F = Modules[i]->getModule()->getNamedFunction(FnName))
67 /// addGlobalMapping - Tell the execution engine that the specified global is
68 /// at the specified location. This is used internally as functions are JIT'd
69 /// and as global variables are laid out in memory. It can and should also be
70 /// used by clients of the EE that want to have an LLVM global overlay
71 /// existing data in memory.
72 void ExecutionEngine::addGlobalMapping(const GlobalValue *GV, void *Addr) {
73 MutexGuard locked(lock);
75 void *&CurVal = state.getGlobalAddressMap(locked)[GV];
76 assert((CurVal == 0 || Addr == 0) && "GlobalMapping already established!");
79 // If we are using the reverse mapping, add it too
80 if (!state.getGlobalAddressReverseMap(locked).empty()) {
81 const GlobalValue *&V = state.getGlobalAddressReverseMap(locked)[Addr];
82 assert((V == 0 || GV == 0) && "GlobalMapping already established!");
87 /// clearAllGlobalMappings - Clear all global mappings and start over again
88 /// use in dynamic compilation scenarios when you want to move globals
89 void ExecutionEngine::clearAllGlobalMappings() {
90 MutexGuard locked(lock);
92 state.getGlobalAddressMap(locked).clear();
93 state.getGlobalAddressReverseMap(locked).clear();
96 /// updateGlobalMapping - Replace an existing mapping for GV with a new
97 /// address. This updates both maps as required. If "Addr" is null, the
98 /// entry for the global is removed from the mappings.
99 void ExecutionEngine::updateGlobalMapping(const GlobalValue *GV, void *Addr) {
100 MutexGuard locked(lock);
102 // Deleting from the mapping?
104 state.getGlobalAddressMap(locked).erase(GV);
105 if (!state.getGlobalAddressReverseMap(locked).empty())
106 state.getGlobalAddressReverseMap(locked).erase(Addr);
110 void *&CurVal = state.getGlobalAddressMap(locked)[GV];
111 if (CurVal && !state.getGlobalAddressReverseMap(locked).empty())
112 state.getGlobalAddressReverseMap(locked).erase(CurVal);
115 // If we are using the reverse mapping, add it too
116 if (!state.getGlobalAddressReverseMap(locked).empty()) {
117 const GlobalValue *&V = state.getGlobalAddressReverseMap(locked)[Addr];
118 assert((V == 0 || GV == 0) && "GlobalMapping already established!");
123 /// getPointerToGlobalIfAvailable - This returns the address of the specified
124 /// global value if it is has already been codegen'd, otherwise it returns null.
126 void *ExecutionEngine::getPointerToGlobalIfAvailable(const GlobalValue *GV) {
127 MutexGuard locked(lock);
129 std::map<const GlobalValue*, void*>::iterator I =
130 state.getGlobalAddressMap(locked).find(GV);
131 return I != state.getGlobalAddressMap(locked).end() ? I->second : 0;
134 /// getGlobalValueAtAddress - Return the LLVM global value object that starts
135 /// at the specified address.
137 const GlobalValue *ExecutionEngine::getGlobalValueAtAddress(void *Addr) {
138 MutexGuard locked(lock);
140 // If we haven't computed the reverse mapping yet, do so first.
141 if (state.getGlobalAddressReverseMap(locked).empty()) {
142 for (std::map<const GlobalValue*, void *>::iterator
143 I = state.getGlobalAddressMap(locked).begin(),
144 E = state.getGlobalAddressMap(locked).end(); I != E; ++I)
145 state.getGlobalAddressReverseMap(locked).insert(std::make_pair(I->second,
149 std::map<void *, const GlobalValue*>::iterator I =
150 state.getGlobalAddressReverseMap(locked).find(Addr);
151 return I != state.getGlobalAddressReverseMap(locked).end() ? I->second : 0;
154 // CreateArgv - Turn a vector of strings into a nice argv style array of
155 // pointers to null terminated strings.
157 static void *CreateArgv(ExecutionEngine *EE,
158 const std::vector<std::string> &InputArgv) {
159 unsigned PtrSize = EE->getTargetData()->getPointerSize();
160 char *Result = new char[(InputArgv.size()+1)*PtrSize];
162 DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n");
163 const Type *SBytePtr = PointerType::get(Type::SByteTy);
165 for (unsigned i = 0; i != InputArgv.size(); ++i) {
166 unsigned Size = InputArgv[i].size()+1;
167 char *Dest = new char[Size];
168 DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n");
170 std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest);
173 // Endian safe: Result[i] = (PointerTy)Dest;
174 EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i*PtrSize),
179 EE->StoreValueToMemory(PTOGV(0),
180 (GenericValue*)(Result+InputArgv.size()*PtrSize),
186 /// runStaticConstructorsDestructors - This method is used to execute all of
187 /// the static constructors or destructors for a program, depending on the
188 /// value of isDtors.
189 void ExecutionEngine::runStaticConstructorsDestructors(bool isDtors) {
190 const char *Name = isDtors ? "llvm.global_dtors" : "llvm.global_ctors";
192 // Execute global ctors/dtors for each module in the program.
193 for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
194 GlobalVariable *GV = Modules[m]->getModule()->getNamedGlobal(Name);
196 // If this global has internal linkage, or if it has a use, then it must be
197 // an old-style (llvmgcc3) static ctor with __main linked in and in use. If
198 // this is the case, don't execute any of the global ctors, __main will do
200 if (!GV || GV->isExternal() || GV->hasInternalLinkage()) continue;
202 // Should be an array of '{ int, void ()* }' structs. The first value is
203 // the init priority, which we ignore.
204 ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
205 if (!InitList) continue;
206 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
207 if (ConstantStruct *CS =
208 dyn_cast<ConstantStruct>(InitList->getOperand(i))) {
209 if (CS->getNumOperands() != 2) break; // Not array of 2-element structs.
211 Constant *FP = CS->getOperand(1);
212 if (FP->isNullValue())
213 break; // Found a null terminator, exit.
215 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(FP))
216 if (CE->getOpcode() == Instruction::Cast)
217 FP = CE->getOperand(0);
218 if (Function *F = dyn_cast<Function>(FP)) {
219 // Execute the ctor/dtor function!
220 runFunction(F, std::vector<GenericValue>());
226 /// runFunctionAsMain - This is a helper function which wraps runFunction to
227 /// handle the common task of starting up main with the specified argc, argv,
228 /// and envp parameters.
229 int ExecutionEngine::runFunctionAsMain(Function *Fn,
230 const std::vector<std::string> &argv,
231 const char * const * envp) {
232 std::vector<GenericValue> GVArgs;
234 GVArgc.IntVal = argv.size();
235 unsigned NumArgs = Fn->getFunctionType()->getNumParams();
237 GVArgs.push_back(GVArgc); // Arg #0 = argc.
239 GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv.
240 assert(((char **)GVTOP(GVArgs[1]))[0] &&
241 "argv[0] was null after CreateArgv");
243 std::vector<std::string> EnvVars;
244 for (unsigned i = 0; envp[i]; ++i)
245 EnvVars.push_back(envp[i]);
246 GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp.
250 return runFunction(Fn, GVArgs).IntVal;
253 /// If possible, create a JIT, unless the caller specifically requests an
254 /// Interpreter or there's an error. If even an Interpreter cannot be created,
255 /// NULL is returned.
257 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
258 bool ForceInterpreter) {
259 ExecutionEngine *EE = 0;
261 // Unless the interpreter was explicitly selected, try making a JIT.
262 if (!ForceInterpreter && JITCtor)
265 // If we can't make a JIT, make an interpreter instead.
266 if (EE == 0 && InterpCtor)
270 // Make sure we can resolve symbols in the program as well. The zero arg
271 // to the function tells DynamicLibrary to load the program, not a library.
273 sys::DynamicLibrary::LoadLibraryPermanently(0);
281 /// getPointerToGlobal - This returns the address of the specified global
282 /// value. This may involve code generation if it's a function.
284 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) {
285 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV)))
286 return getPointerToFunction(F);
288 MutexGuard locked(lock);
289 void *p = state.getGlobalAddressMap(locked)[GV];
293 // Global variable might have been added since interpreter started.
294 if (GlobalVariable *GVar =
295 const_cast<GlobalVariable *>(dyn_cast<GlobalVariable>(GV)))
296 EmitGlobalVariable(GVar);
298 assert("Global hasn't had an address allocated yet!");
299 return state.getGlobalAddressMap(locked)[GV];
304 GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
306 if (isa<UndefValue>(C)) return Result;
308 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) {
309 switch (CE->getOpcode()) {
310 case Instruction::GetElementPtr: {
311 Result = getConstantValue(CE->getOperand(0));
312 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end());
314 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes);
316 if (getTargetData()->getPointerSize() == 4)
317 Result.IntVal += Offset;
319 Result.LongVal += Offset;
322 case Instruction::Cast: {
323 // We only need to handle a few cases here. Almost all casts will
324 // automatically fold, just the ones involving pointers won't.
326 Constant *Op = CE->getOperand(0);
327 GenericValue GV = getConstantValue(Op);
329 // Handle cast of pointer to pointer...
330 if (Op->getType()->getTypeID() == C->getType()->getTypeID())
333 // Handle a cast of pointer to any integral type...
334 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral())
337 // Handle cast of integer to a pointer...
338 if (isa<PointerType>(C->getType()) && Op->getType()->isIntegral())
339 switch (Op->getType()->getTypeID()) {
340 case Type::BoolTyID: return PTOGV((void*)(uintptr_t)GV.BoolVal);
341 case Type::SByteTyID: return PTOGV((void*)( intptr_t)GV.SByteVal);
342 case Type::UByteTyID: return PTOGV((void*)(uintptr_t)GV.UByteVal);
343 case Type::ShortTyID: return PTOGV((void*)( intptr_t)GV.ShortVal);
344 case Type::UShortTyID: return PTOGV((void*)(uintptr_t)GV.UShortVal);
345 case Type::IntTyID: return PTOGV((void*)( intptr_t)GV.IntVal);
346 case Type::UIntTyID: return PTOGV((void*)(uintptr_t)GV.UIntVal);
347 case Type::LongTyID: return PTOGV((void*)( intptr_t)GV.LongVal);
348 case Type::ULongTyID: return PTOGV((void*)(uintptr_t)GV.ULongVal);
349 default: assert(0 && "Unknown integral type!");
354 case Instruction::Add:
355 switch (CE->getOperand(0)->getType()->getTypeID()) {
356 default: assert(0 && "Bad add type!"); abort();
358 case Type::ULongTyID:
359 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal +
360 getConstantValue(CE->getOperand(1)).LongVal;
364 Result.IntVal = getConstantValue(CE->getOperand(0)).IntVal +
365 getConstantValue(CE->getOperand(1)).IntVal;
367 case Type::ShortTyID:
368 case Type::UShortTyID:
369 Result.ShortVal = getConstantValue(CE->getOperand(0)).ShortVal +
370 getConstantValue(CE->getOperand(1)).ShortVal;
372 case Type::SByteTyID:
373 case Type::UByteTyID:
374 Result.SByteVal = getConstantValue(CE->getOperand(0)).SByteVal +
375 getConstantValue(CE->getOperand(1)).SByteVal;
377 case Type::FloatTyID:
378 Result.FloatVal = getConstantValue(CE->getOperand(0)).FloatVal +
379 getConstantValue(CE->getOperand(1)).FloatVal;
381 case Type::DoubleTyID:
382 Result.DoubleVal = getConstantValue(CE->getOperand(0)).DoubleVal +
383 getConstantValue(CE->getOperand(1)).DoubleVal;
390 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n";
394 switch (C->getType()->getTypeID()) {
395 #define GET_CONST_VAL(TY, CTY, CLASS, GETMETH) \
396 case Type::TY##TyID: Result.TY##Val = (CTY)cast<CLASS>(C)->GETMETH(); break
397 GET_CONST_VAL(Bool , bool , ConstantBool, getValue);
398 GET_CONST_VAL(UByte , unsigned char , ConstantInt, getZExtValue);
399 GET_CONST_VAL(SByte , signed char , ConstantInt, getSExtValue);
400 GET_CONST_VAL(UShort , unsigned short, ConstantInt, getZExtValue);
401 GET_CONST_VAL(Short , signed short , ConstantInt, getSExtValue);
402 GET_CONST_VAL(UInt , unsigned int , ConstantInt, getZExtValue);
403 GET_CONST_VAL(Int , signed int , ConstantInt, getSExtValue);
404 GET_CONST_VAL(ULong , uint64_t , ConstantInt, getZExtValue);
405 GET_CONST_VAL(Long , int64_t , ConstantInt, getSExtValue);
406 GET_CONST_VAL(Float , float , ConstantFP, getValue);
407 GET_CONST_VAL(Double , double , ConstantFP, getValue);
409 case Type::PointerTyID:
410 if (isa<ConstantPointerNull>(C))
411 Result.PointerVal = 0;
412 else if (const Function *F = dyn_cast<Function>(C))
413 Result = PTOGV(getPointerToFunctionOrStub(const_cast<Function*>(F)));
414 else if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C))
415 Result = PTOGV(getOrEmitGlobalVariable(const_cast<GlobalVariable*>(GV)));
417 assert(0 && "Unknown constant pointer type!");
420 std::cout << "ERROR: Constant unimp for type: " << *C->getType() << "\n";
426 /// StoreValueToMemory - Stores the data in Val of type Ty at address Ptr. Ptr
427 /// is the address of the memory at which to store Val, cast to GenericValue *.
428 /// It is not a pointer to a GenericValue containing the address at which to
431 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr,
433 if (getTargetData()->isLittleEndian()) {
434 switch (Ty->getTypeID()) {
436 case Type::UByteTyID:
437 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
438 case Type::UShortTyID:
439 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255;
440 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255;
442 Store4BytesLittleEndian:
443 case Type::FloatTyID:
445 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255;
446 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255;
447 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255;
448 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255;
450 case Type::PointerTyID: if (getTargetData()->getPointerSize() == 4)
451 goto Store4BytesLittleEndian;
452 case Type::DoubleTyID:
453 case Type::ULongTyID:
455 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal );
456 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 8);
457 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 16);
458 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 24);
459 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 32);
460 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 40);
461 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 48);
462 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal >> 56);
465 std::cout << "Cannot store value of type " << *Ty << "!\n";
468 switch (Ty->getTypeID()) {
470 case Type::UByteTyID:
471 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
472 case Type::UShortTyID:
473 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255;
474 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255;
476 Store4BytesBigEndian:
477 case Type::FloatTyID:
479 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255;
480 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255;
481 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255;
482 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255;
484 case Type::PointerTyID: if (getTargetData()->getPointerSize() == 4)
485 goto Store4BytesBigEndian;
486 case Type::DoubleTyID:
487 case Type::ULongTyID:
489 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal );
490 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 8);
491 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 16);
492 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 24);
493 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 32);
494 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 40);
495 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 48);
496 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal >> 56);
499 std::cout << "Cannot store value of type " << *Ty << "!\n";
506 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr,
509 if (getTargetData()->isLittleEndian()) {
510 switch (Ty->getTypeID()) {
512 case Type::UByteTyID:
513 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
514 case Type::UShortTyID:
515 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] |
516 ((unsigned)Ptr->Untyped[1] << 8);
518 Load4BytesLittleEndian:
519 case Type::FloatTyID:
521 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] |
522 ((unsigned)Ptr->Untyped[1] << 8) |
523 ((unsigned)Ptr->Untyped[2] << 16) |
524 ((unsigned)Ptr->Untyped[3] << 24);
526 case Type::PointerTyID: if (getTargetData()->getPointerSize() == 4)
527 goto Load4BytesLittleEndian;
528 case Type::DoubleTyID:
529 case Type::ULongTyID:
530 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] |
531 ((uint64_t)Ptr->Untyped[1] << 8) |
532 ((uint64_t)Ptr->Untyped[2] << 16) |
533 ((uint64_t)Ptr->Untyped[3] << 24) |
534 ((uint64_t)Ptr->Untyped[4] << 32) |
535 ((uint64_t)Ptr->Untyped[5] << 40) |
536 ((uint64_t)Ptr->Untyped[6] << 48) |
537 ((uint64_t)Ptr->Untyped[7] << 56);
540 std::cout << "Cannot load value of type " << *Ty << "!\n";
544 switch (Ty->getTypeID()) {
546 case Type::UByteTyID:
547 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
548 case Type::UShortTyID:
549 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] |
550 ((unsigned)Ptr->Untyped[0] << 8);
553 case Type::FloatTyID:
555 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] |
556 ((unsigned)Ptr->Untyped[2] << 8) |
557 ((unsigned)Ptr->Untyped[1] << 16) |
558 ((unsigned)Ptr->Untyped[0] << 24);
560 case Type::PointerTyID: if (getTargetData()->getPointerSize() == 4)
561 goto Load4BytesBigEndian;
562 case Type::DoubleTyID:
563 case Type::ULongTyID:
564 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] |
565 ((uint64_t)Ptr->Untyped[6] << 8) |
566 ((uint64_t)Ptr->Untyped[5] << 16) |
567 ((uint64_t)Ptr->Untyped[4] << 24) |
568 ((uint64_t)Ptr->Untyped[3] << 32) |
569 ((uint64_t)Ptr->Untyped[2] << 40) |
570 ((uint64_t)Ptr->Untyped[1] << 48) |
571 ((uint64_t)Ptr->Untyped[0] << 56);
574 std::cout << "Cannot load value of type " << *Ty << "!\n";
581 // InitializeMemory - Recursive function to apply a Constant value into the
582 // specified memory location...
584 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) {
585 if (isa<UndefValue>(Init)) {
587 } else if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(Init)) {
588 unsigned ElementSize =
589 getTargetData()->getTypeSize(CP->getType()->getElementType());
590 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
591 InitializeMemory(CP->getOperand(i), (char*)Addr+i*ElementSize);
593 } else if (Init->getType()->isFirstClassType()) {
594 GenericValue Val = getConstantValue(Init);
595 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
597 } else if (isa<ConstantAggregateZero>(Init)) {
598 memset(Addr, 0, (size_t)getTargetData()->getTypeSize(Init->getType()));
602 switch (Init->getType()->getTypeID()) {
603 case Type::ArrayTyID: {
604 const ConstantArray *CPA = cast<ConstantArray>(Init);
605 unsigned ElementSize =
606 getTargetData()->getTypeSize(CPA->getType()->getElementType());
607 for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i)
608 InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize);
612 case Type::StructTyID: {
613 const ConstantStruct *CPS = cast<ConstantStruct>(Init);
614 const StructLayout *SL =
615 getTargetData()->getStructLayout(cast<StructType>(CPS->getType()));
616 for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i)
617 InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->MemberOffsets[i]);
622 std::cerr << "Bad Type: " << *Init->getType() << "\n";
623 assert(0 && "Unknown constant type to initialize memory with!");
627 /// EmitGlobals - Emit all of the global variables to memory, storing their
628 /// addresses into GlobalAddress. This must make sure to copy the contents of
629 /// their initializers into the memory.
631 void ExecutionEngine::emitGlobals() {
632 const TargetData *TD = getTargetData();
634 // Loop over all of the global variables in the program, allocating the memory
635 // to hold them. If there is more than one module, do a prepass over globals
636 // to figure out how the different modules should link together.
638 std::map<std::pair<std::string, const Type*>,
639 const GlobalValue*> LinkedGlobalsMap;
641 if (Modules.size() != 1) {
642 for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
643 Module &M = *Modules[m]->getModule();
644 for (Module::const_global_iterator I = M.global_begin(),
645 E = M.global_end(); I != E; ++I) {
646 const GlobalValue *GV = I;
647 if (GV->hasInternalLinkage() || GV->isExternal() ||
648 GV->hasAppendingLinkage() || !GV->hasName())
649 continue;// Ignore external globals and globals with internal linkage.
651 const GlobalValue *&GVEntry =
652 LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())];
654 // If this is the first time we've seen this global, it is the canonical
661 // If the existing global is strong, never replace it.
662 if (GVEntry->hasExternalLinkage() ||
663 GVEntry->hasDLLImportLinkage() ||
664 GVEntry->hasDLLExportLinkage())
667 // Otherwise, we know it's linkonce/weak, replace it if this is a strong
669 if (GV->hasExternalLinkage())
675 std::vector<const GlobalValue*> NonCanonicalGlobals;
676 for (unsigned m = 0, e = Modules.size(); m != e; ++m) {
677 Module &M = *Modules[m]->getModule();
678 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
680 // In the multi-module case, see what this global maps to.
681 if (!LinkedGlobalsMap.empty()) {
682 if (const GlobalValue *GVEntry =
683 LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())]) {
684 // If something else is the canonical global, ignore this one.
685 if (GVEntry != &*I) {
686 NonCanonicalGlobals.push_back(I);
692 if (!I->isExternal()) {
693 // Get the type of the global.
694 const Type *Ty = I->getType()->getElementType();
696 // Allocate some memory for it!
697 unsigned Size = TD->getTypeSize(Ty);
698 addGlobalMapping(I, new char[Size]);
700 // External variable reference. Try to use the dynamic loader to
701 // get a pointer to it.
703 sys::DynamicLibrary::SearchForAddressOfSymbol(I->getName().c_str()))
704 addGlobalMapping(I, SymAddr);
706 std::cerr << "Could not resolve external global address: "
707 << I->getName() << "\n";
713 // If there are multiple modules, map the non-canonical globals to their
714 // canonical location.
715 if (!NonCanonicalGlobals.empty()) {
716 for (unsigned i = 0, e = NonCanonicalGlobals.size(); i != e; ++i) {
717 const GlobalValue *GV = NonCanonicalGlobals[i];
718 const GlobalValue *CGV =
719 LinkedGlobalsMap[std::make_pair(GV->getName(), GV->getType())];
720 void *Ptr = getPointerToGlobalIfAvailable(CGV);
721 assert(Ptr && "Canonical global wasn't codegen'd!");
722 addGlobalMapping(GV, getPointerToGlobalIfAvailable(CGV));
726 // Now that all of the globals are set up in memory, loop through them all and
727 // initialize their contents.
728 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
730 if (!I->isExternal()) {
731 if (!LinkedGlobalsMap.empty()) {
732 if (const GlobalValue *GVEntry =
733 LinkedGlobalsMap[std::make_pair(I->getName(), I->getType())])
734 if (GVEntry != &*I) // Not the canonical variable.
737 EmitGlobalVariable(I);
743 // EmitGlobalVariable - This method emits the specified global variable to the
744 // address specified in GlobalAddresses, or allocates new memory if it's not
745 // already in the map.
746 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) {
747 void *GA = getPointerToGlobalIfAvailable(GV);
748 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n");
750 const Type *ElTy = GV->getType()->getElementType();
751 size_t GVSize = (size_t)getTargetData()->getTypeSize(ElTy);
753 // If it's not already specified, allocate memory for the global.
754 GA = new char[GVSize];
755 addGlobalMapping(GV, GA);
758 InitializeMemory(GV->getInitializer(), GA);
759 NumInitBytes += (unsigned)GVSize;