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/System/DynamicLibrary.h"
25 #include "llvm/Target/TargetData.h"
30 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized");
31 Statistic<> NumGlobals ("lli", "Number of global vars initialized");
34 ExecutionEngine::EECtorFn ExecutionEngine::JITCtor = 0;
35 ExecutionEngine::EECtorFn ExecutionEngine::InterpCtor = 0;
37 ExecutionEngine::ExecutionEngine(ModuleProvider *P) :
38 CurMod(*P->getModule()), MP(P) {
39 assert(P && "ModuleProvider is null?");
42 ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) {
43 assert(M && "Module is null?");
46 ExecutionEngine::~ExecutionEngine() {
50 /// getGlobalValueAtAddress - Return the LLVM global value object that starts
51 /// at the specified address.
53 const GlobalValue *ExecutionEngine::getGlobalValueAtAddress(void *Addr) {
54 MutexGuard locked(lock);
56 // If we haven't computed the reverse mapping yet, do so first.
57 if (state.getGlobalAddressReverseMap(locked).empty()) {
58 for (std::map<const GlobalValue*, void *>::iterator I =
59 state.getGlobalAddressMap(locked).begin(), E = state.getGlobalAddressMap(locked).end(); I != E; ++I)
60 state.getGlobalAddressReverseMap(locked).insert(std::make_pair(I->second, I->first));
63 std::map<void *, const GlobalValue*>::iterator I =
64 state.getGlobalAddressReverseMap(locked).find(Addr);
65 return I != state.getGlobalAddressReverseMap(locked).end() ? I->second : 0;
68 // CreateArgv - Turn a vector of strings into a nice argv style array of
69 // pointers to null terminated strings.
71 static void *CreateArgv(ExecutionEngine *EE,
72 const std::vector<std::string> &InputArgv) {
73 unsigned PtrSize = EE->getTargetData().getPointerSize();
74 char *Result = new char[(InputArgv.size()+1)*PtrSize];
76 DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n");
77 const Type *SBytePtr = PointerType::get(Type::SByteTy);
79 for (unsigned i = 0; i != InputArgv.size(); ++i) {
80 unsigned Size = InputArgv[i].size()+1;
81 char *Dest = new char[Size];
82 DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n");
84 std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest);
87 // Endian safe: Result[i] = (PointerTy)Dest;
88 EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i*PtrSize),
93 EE->StoreValueToMemory(PTOGV(0),
94 (GenericValue*)(Result+InputArgv.size()*PtrSize),
100 /// runStaticConstructorsDestructors - This method is used to execute all of
101 /// the static constructors or destructors for a module, depending on the
102 /// value of isDtors.
103 void ExecutionEngine::runStaticConstructorsDestructors(bool isDtors) {
104 const char *Name = isDtors ? "llvm.global_dtors" : "llvm.global_ctors";
105 GlobalVariable *GV = CurMod.getNamedGlobal(Name);
107 // If this global has internal linkage, or if it has a use, then it must be
108 // an old-style (llvmgcc3) static ctor with __main linked in and in use. If
109 // this is the case, don't execute any of the global ctors, __main will do it.
110 if (!GV || GV->isExternal() || GV->hasInternalLinkage()) return;
112 // Should be an array of '{ int, void ()* }' structs. The first value is the
113 // init priority, which we ignore.
114 ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
115 if (!InitList) return;
116 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
117 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
118 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
120 Constant *FP = CS->getOperand(1);
121 if (FP->isNullValue())
122 return; // Found a null terminator, exit.
124 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(FP))
125 if (CE->getOpcode() == Instruction::Cast)
126 FP = CE->getOperand(0);
127 if (Function *F = dyn_cast<Function>(FP)) {
128 // Execute the ctor/dtor function!
129 runFunction(F, std::vector<GenericValue>());
134 /// runFunctionAsMain - This is a helper function which wraps runFunction to
135 /// handle the common task of starting up main with the specified argc, argv,
136 /// and envp parameters.
137 int ExecutionEngine::runFunctionAsMain(Function *Fn,
138 const std::vector<std::string> &argv,
139 const char * const * envp) {
140 std::vector<GenericValue> GVArgs;
142 GVArgc.IntVal = argv.size();
143 unsigned NumArgs = Fn->getFunctionType()->getNumParams();
145 GVArgs.push_back(GVArgc); // Arg #0 = argc.
147 GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv.
148 assert(((char **)GVTOP(GVArgs[1]))[0] &&
149 "argv[0] was null after CreateArgv");
151 std::vector<std::string> EnvVars;
152 for (unsigned i = 0; envp[i]; ++i)
153 EnvVars.push_back(envp[i]);
154 GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp.
158 return runFunction(Fn, GVArgs).IntVal;
161 /// If possible, create a JIT, unless the caller specifically requests an
162 /// Interpreter or there's an error. If even an Interpreter cannot be created,
163 /// NULL is returned.
165 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
166 bool ForceInterpreter) {
167 ExecutionEngine *EE = 0;
169 // Unless the interpreter was explicitly selected, try making a JIT.
170 if (!ForceInterpreter && JITCtor)
173 // If we can't make a JIT, make an interpreter instead.
174 if (EE == 0 && InterpCtor)
178 // Make sure we can resolve symbols in the program as well. The zero arg
179 // to the function tells DynamicLibrary to load the program, not a library.
180 sys::DynamicLibrary::LoadLibraryPermanently(0);
186 /// getPointerToGlobal - This returns the address of the specified global
187 /// value. This may involve code generation if it's a function.
189 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) {
190 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV)))
191 return getPointerToFunction(F);
193 MutexGuard locked(lock);
194 void *p = state.getGlobalAddressMap(locked)[GV];
198 // Global variable might have been added since interpreter started.
199 if (GlobalVariable *GVar =
200 const_cast<GlobalVariable *>(dyn_cast<GlobalVariable>(GV)))
201 EmitGlobalVariable(GVar);
203 assert("Global hasn't had an address allocated yet!");
204 return state.getGlobalAddressMap(locked)[GV];
209 GenericValue ExecutionEngine::getConstantValue(const Constant *C) {
211 if (isa<UndefValue>(C)) return Result;
213 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) {
214 switch (CE->getOpcode()) {
215 case Instruction::GetElementPtr: {
216 Result = getConstantValue(CE->getOperand(0));
217 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end());
219 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes);
221 if (getTargetData().getPointerSize() == 4)
222 Result.IntVal += Offset;
224 Result.LongVal += Offset;
227 case Instruction::Cast: {
228 // We only need to handle a few cases here. Almost all casts will
229 // automatically fold, just the ones involving pointers won't.
231 Constant *Op = CE->getOperand(0);
232 GenericValue GV = getConstantValue(Op);
234 // Handle cast of pointer to pointer...
235 if (Op->getType()->getTypeID() == C->getType()->getTypeID())
238 // Handle a cast of pointer to any integral type...
239 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral())
242 // Handle cast of integer to a pointer...
243 if (isa<PointerType>(C->getType()) && Op->getType()->isIntegral())
244 switch (Op->getType()->getTypeID()) {
245 case Type::BoolTyID: return PTOGV((void*)(uintptr_t)GV.BoolVal);
246 case Type::SByteTyID: return PTOGV((void*)( intptr_t)GV.SByteVal);
247 case Type::UByteTyID: return PTOGV((void*)(uintptr_t)GV.UByteVal);
248 case Type::ShortTyID: return PTOGV((void*)( intptr_t)GV.ShortVal);
249 case Type::UShortTyID: return PTOGV((void*)(uintptr_t)GV.UShortVal);
250 case Type::IntTyID: return PTOGV((void*)( intptr_t)GV.IntVal);
251 case Type::UIntTyID: return PTOGV((void*)(uintptr_t)GV.UIntVal);
252 case Type::LongTyID: return PTOGV((void*)( intptr_t)GV.LongVal);
253 case Type::ULongTyID: return PTOGV((void*)(uintptr_t)GV.ULongVal);
254 default: assert(0 && "Unknown integral type!");
259 case Instruction::Add:
260 switch (CE->getOperand(0)->getType()->getTypeID()) {
261 default: assert(0 && "Bad add type!"); abort();
263 case Type::ULongTyID:
264 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal +
265 getConstantValue(CE->getOperand(1)).LongVal;
269 Result.IntVal = getConstantValue(CE->getOperand(0)).IntVal +
270 getConstantValue(CE->getOperand(1)).IntVal;
272 case Type::ShortTyID:
273 case Type::UShortTyID:
274 Result.ShortVal = getConstantValue(CE->getOperand(0)).ShortVal +
275 getConstantValue(CE->getOperand(1)).ShortVal;
277 case Type::SByteTyID:
278 case Type::UByteTyID:
279 Result.SByteVal = getConstantValue(CE->getOperand(0)).SByteVal +
280 getConstantValue(CE->getOperand(1)).SByteVal;
282 case Type::FloatTyID:
283 Result.FloatVal = getConstantValue(CE->getOperand(0)).FloatVal +
284 getConstantValue(CE->getOperand(1)).FloatVal;
286 case Type::DoubleTyID:
287 Result.DoubleVal = getConstantValue(CE->getOperand(0)).DoubleVal +
288 getConstantValue(CE->getOperand(1)).DoubleVal;
295 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n";
299 switch (C->getType()->getTypeID()) {
300 #define GET_CONST_VAL(TY, CTY, CLASS) \
301 case Type::TY##TyID: Result.TY##Val = (CTY)cast<CLASS>(C)->getValue(); break
302 GET_CONST_VAL(Bool , bool , ConstantBool);
303 GET_CONST_VAL(UByte , unsigned char , ConstantUInt);
304 GET_CONST_VAL(SByte , signed char , ConstantSInt);
305 GET_CONST_VAL(UShort , unsigned short, ConstantUInt);
306 GET_CONST_VAL(Short , signed short , ConstantSInt);
307 GET_CONST_VAL(UInt , unsigned int , ConstantUInt);
308 GET_CONST_VAL(Int , signed int , ConstantSInt);
309 GET_CONST_VAL(ULong , uint64_t , ConstantUInt);
310 GET_CONST_VAL(Long , int64_t , ConstantSInt);
311 GET_CONST_VAL(Float , float , ConstantFP);
312 GET_CONST_VAL(Double , double , ConstantFP);
314 case Type::PointerTyID:
315 if (isa<ConstantPointerNull>(C))
316 Result.PointerVal = 0;
317 else if (const Function *F = dyn_cast<Function>(C))
318 Result = PTOGV(getPointerToFunctionOrStub(const_cast<Function*>(F)));
319 else if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C))
320 Result = PTOGV(getOrEmitGlobalVariable(const_cast<GlobalVariable*>(GV)));
322 assert(0 && "Unknown constant pointer type!");
325 std::cout << "ERROR: Constant unimp for type: " << *C->getType() << "\n";
331 /// StoreValueToMemory - Stores the data in Val of type Ty at address Ptr. Ptr
332 /// is the address of the memory at which to store Val, cast to GenericValue *.
333 /// It is not a pointer to a GenericValue containing the address at which to
336 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr,
338 if (getTargetData().isLittleEndian()) {
339 switch (Ty->getTypeID()) {
341 case Type::UByteTyID:
342 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
343 case Type::UShortTyID:
344 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255;
345 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255;
347 Store4BytesLittleEndian:
348 case Type::FloatTyID:
350 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255;
351 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255;
352 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255;
353 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255;
355 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
356 goto Store4BytesLittleEndian;
357 case Type::DoubleTyID:
358 case Type::ULongTyID:
360 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal );
361 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 8);
362 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 16);
363 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 24);
364 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 32);
365 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 40);
366 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 48);
367 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal >> 56);
370 std::cout << "Cannot store value of type " << *Ty << "!\n";
373 switch (Ty->getTypeID()) {
375 case Type::UByteTyID:
376 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
377 case Type::UShortTyID:
378 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255;
379 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255;
381 Store4BytesBigEndian:
382 case Type::FloatTyID:
384 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255;
385 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255;
386 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255;
387 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255;
389 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
390 goto Store4BytesBigEndian;
391 case Type::DoubleTyID:
392 case Type::ULongTyID:
394 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal );
395 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 8);
396 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 16);
397 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 24);
398 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 32);
399 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 40);
400 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 48);
401 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal >> 56);
404 std::cout << "Cannot store value of type " << *Ty << "!\n";
411 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr,
414 if (getTargetData().isLittleEndian()) {
415 switch (Ty->getTypeID()) {
417 case Type::UByteTyID:
418 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
419 case Type::UShortTyID:
420 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] |
421 ((unsigned)Ptr->Untyped[1] << 8);
423 Load4BytesLittleEndian:
424 case Type::FloatTyID:
426 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] |
427 ((unsigned)Ptr->Untyped[1] << 8) |
428 ((unsigned)Ptr->Untyped[2] << 16) |
429 ((unsigned)Ptr->Untyped[3] << 24);
431 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
432 goto Load4BytesLittleEndian;
433 case Type::DoubleTyID:
434 case Type::ULongTyID:
435 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] |
436 ((uint64_t)Ptr->Untyped[1] << 8) |
437 ((uint64_t)Ptr->Untyped[2] << 16) |
438 ((uint64_t)Ptr->Untyped[3] << 24) |
439 ((uint64_t)Ptr->Untyped[4] << 32) |
440 ((uint64_t)Ptr->Untyped[5] << 40) |
441 ((uint64_t)Ptr->Untyped[6] << 48) |
442 ((uint64_t)Ptr->Untyped[7] << 56);
445 std::cout << "Cannot load value of type " << *Ty << "!\n";
449 switch (Ty->getTypeID()) {
451 case Type::UByteTyID:
452 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
453 case Type::UShortTyID:
454 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] |
455 ((unsigned)Ptr->Untyped[0] << 8);
458 case Type::FloatTyID:
460 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] |
461 ((unsigned)Ptr->Untyped[2] << 8) |
462 ((unsigned)Ptr->Untyped[1] << 16) |
463 ((unsigned)Ptr->Untyped[0] << 24);
465 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
466 goto Load4BytesBigEndian;
467 case Type::DoubleTyID:
468 case Type::ULongTyID:
469 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] |
470 ((uint64_t)Ptr->Untyped[6] << 8) |
471 ((uint64_t)Ptr->Untyped[5] << 16) |
472 ((uint64_t)Ptr->Untyped[4] << 24) |
473 ((uint64_t)Ptr->Untyped[3] << 32) |
474 ((uint64_t)Ptr->Untyped[2] << 40) |
475 ((uint64_t)Ptr->Untyped[1] << 48) |
476 ((uint64_t)Ptr->Untyped[0] << 56);
479 std::cout << "Cannot load value of type " << *Ty << "!\n";
486 // InitializeMemory - Recursive function to apply a Constant value into the
487 // specified memory location...
489 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) {
490 if (isa<UndefValue>(Init)) {
492 } else if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(Init)) {
493 unsigned ElementSize =
494 getTargetData().getTypeSize(CP->getType()->getElementType());
495 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
496 InitializeMemory(CP->getOperand(i), (char*)Addr+i*ElementSize);
498 } else if (Init->getType()->isFirstClassType()) {
499 GenericValue Val = getConstantValue(Init);
500 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
502 } else if (isa<ConstantAggregateZero>(Init)) {
503 memset(Addr, 0, (size_t)getTargetData().getTypeSize(Init->getType()));
507 switch (Init->getType()->getTypeID()) {
508 case Type::ArrayTyID: {
509 const ConstantArray *CPA = cast<ConstantArray>(Init);
510 unsigned ElementSize =
511 getTargetData().getTypeSize(CPA->getType()->getElementType());
512 for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i)
513 InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize);
517 case Type::StructTyID: {
518 const ConstantStruct *CPS = cast<ConstantStruct>(Init);
519 const StructLayout *SL =
520 getTargetData().getStructLayout(cast<StructType>(CPS->getType()));
521 for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i)
522 InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->MemberOffsets[i]);
527 std::cerr << "Bad Type: " << *Init->getType() << "\n";
528 assert(0 && "Unknown constant type to initialize memory with!");
532 /// EmitGlobals - Emit all of the global variables to memory, storing their
533 /// addresses into GlobalAddress. This must make sure to copy the contents of
534 /// their initializers into the memory.
536 void ExecutionEngine::emitGlobals() {
537 const TargetData &TD = getTargetData();
539 // Loop over all of the global variables in the program, allocating the memory
541 Module &M = getModule();
542 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
544 if (!I->isExternal()) {
545 // Get the type of the global...
546 const Type *Ty = I->getType()->getElementType();
548 // Allocate some memory for it!
549 unsigned Size = TD.getTypeSize(Ty);
550 addGlobalMapping(I, new char[Size]);
552 // External variable reference. Try to use the dynamic loader to
553 // get a pointer to it.
554 if (void *SymAddr = sys::DynamicLibrary::SearchForAddressOfSymbol(
555 I->getName().c_str()))
556 addGlobalMapping(I, SymAddr);
558 std::cerr << "Could not resolve external global address: "
559 << I->getName() << "\n";
564 // Now that all of the globals are set up in memory, loop through them all and
565 // initialize their contents.
566 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
568 if (!I->isExternal())
569 EmitGlobalVariable(I);
572 // EmitGlobalVariable - This method emits the specified global variable to the
573 // address specified in GlobalAddresses, or allocates new memory if it's not
574 // already in the map.
575 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) {
576 void *GA = getPointerToGlobalIfAvailable(GV);
577 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n");
579 const Type *ElTy = GV->getType()->getElementType();
580 size_t GVSize = (size_t)getTargetData().getTypeSize(ElTy);
582 // If it's not already specified, allocate memory for the global.
583 GA = new char[GVSize];
584 addGlobalMapping(GV, GA);
587 InitializeMemory(GV->getInitializer(), GA);
588 NumInitBytes += (unsigned)GVSize;