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";
333 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr,
335 if (getTargetData().isLittleEndian()) {
336 switch (Ty->getTypeID()) {
338 case Type::UByteTyID:
339 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
340 case Type::UShortTyID:
341 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255;
342 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255;
344 Store4BytesLittleEndian:
345 case Type::FloatTyID:
347 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255;
348 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255;
349 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255;
350 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255;
352 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
353 goto Store4BytesLittleEndian;
354 case Type::DoubleTyID:
355 case Type::ULongTyID:
357 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal );
358 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 8);
359 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 16);
360 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 24);
361 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 32);
362 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 40);
363 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 48);
364 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal >> 56);
367 std::cout << "Cannot store value of type " << *Ty << "!\n";
370 switch (Ty->getTypeID()) {
372 case Type::UByteTyID:
373 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break;
374 case Type::UShortTyID:
375 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255;
376 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255;
378 Store4BytesBigEndian:
379 case Type::FloatTyID:
381 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255;
382 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255;
383 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255;
384 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255;
386 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
387 goto Store4BytesBigEndian;
388 case Type::DoubleTyID:
389 case Type::ULongTyID:
391 Ptr->Untyped[7] = (unsigned char)(Val.ULongVal );
392 Ptr->Untyped[6] = (unsigned char)(Val.ULongVal >> 8);
393 Ptr->Untyped[5] = (unsigned char)(Val.ULongVal >> 16);
394 Ptr->Untyped[4] = (unsigned char)(Val.ULongVal >> 24);
395 Ptr->Untyped[3] = (unsigned char)(Val.ULongVal >> 32);
396 Ptr->Untyped[2] = (unsigned char)(Val.ULongVal >> 40);
397 Ptr->Untyped[1] = (unsigned char)(Val.ULongVal >> 48);
398 Ptr->Untyped[0] = (unsigned char)(Val.ULongVal >> 56);
401 std::cout << "Cannot store value of type " << *Ty << "!\n";
408 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr,
411 if (getTargetData().isLittleEndian()) {
412 switch (Ty->getTypeID()) {
414 case Type::UByteTyID:
415 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
416 case Type::UShortTyID:
417 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] |
418 ((unsigned)Ptr->Untyped[1] << 8);
420 Load4BytesLittleEndian:
421 case Type::FloatTyID:
423 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] |
424 ((unsigned)Ptr->Untyped[1] << 8) |
425 ((unsigned)Ptr->Untyped[2] << 16) |
426 ((unsigned)Ptr->Untyped[3] << 24);
428 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
429 goto Load4BytesLittleEndian;
430 case Type::DoubleTyID:
431 case Type::ULongTyID:
432 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] |
433 ((uint64_t)Ptr->Untyped[1] << 8) |
434 ((uint64_t)Ptr->Untyped[2] << 16) |
435 ((uint64_t)Ptr->Untyped[3] << 24) |
436 ((uint64_t)Ptr->Untyped[4] << 32) |
437 ((uint64_t)Ptr->Untyped[5] << 40) |
438 ((uint64_t)Ptr->Untyped[6] << 48) |
439 ((uint64_t)Ptr->Untyped[7] << 56);
442 std::cout << "Cannot load value of type " << *Ty << "!\n";
446 switch (Ty->getTypeID()) {
448 case Type::UByteTyID:
449 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break;
450 case Type::UShortTyID:
451 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] |
452 ((unsigned)Ptr->Untyped[0] << 8);
455 case Type::FloatTyID:
457 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] |
458 ((unsigned)Ptr->Untyped[2] << 8) |
459 ((unsigned)Ptr->Untyped[1] << 16) |
460 ((unsigned)Ptr->Untyped[0] << 24);
462 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4)
463 goto Load4BytesBigEndian;
464 case Type::DoubleTyID:
465 case Type::ULongTyID:
466 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] |
467 ((uint64_t)Ptr->Untyped[6] << 8) |
468 ((uint64_t)Ptr->Untyped[5] << 16) |
469 ((uint64_t)Ptr->Untyped[4] << 24) |
470 ((uint64_t)Ptr->Untyped[3] << 32) |
471 ((uint64_t)Ptr->Untyped[2] << 40) |
472 ((uint64_t)Ptr->Untyped[1] << 48) |
473 ((uint64_t)Ptr->Untyped[0] << 56);
476 std::cout << "Cannot load value of type " << *Ty << "!\n";
483 // InitializeMemory - Recursive function to apply a Constant value into the
484 // specified memory location...
486 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) {
487 if (isa<UndefValue>(Init)) {
489 } else if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(Init)) {
490 unsigned ElementSize =
491 getTargetData().getTypeSize(CP->getType()->getElementType());
492 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
493 InitializeMemory(CP->getOperand(i), (char*)Addr+i*ElementSize);
495 } else if (Init->getType()->isFirstClassType()) {
496 GenericValue Val = getConstantValue(Init);
497 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType());
499 } else if (isa<ConstantAggregateZero>(Init)) {
500 memset(Addr, 0, (size_t)getTargetData().getTypeSize(Init->getType()));
504 switch (Init->getType()->getTypeID()) {
505 case Type::ArrayTyID: {
506 const ConstantArray *CPA = cast<ConstantArray>(Init);
507 unsigned ElementSize =
508 getTargetData().getTypeSize(CPA->getType()->getElementType());
509 for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i)
510 InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize);
514 case Type::StructTyID: {
515 const ConstantStruct *CPS = cast<ConstantStruct>(Init);
516 const StructLayout *SL =
517 getTargetData().getStructLayout(cast<StructType>(CPS->getType()));
518 for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i)
519 InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->MemberOffsets[i]);
524 std::cerr << "Bad Type: " << *Init->getType() << "\n";
525 assert(0 && "Unknown constant type to initialize memory with!");
529 /// EmitGlobals - Emit all of the global variables to memory, storing their
530 /// addresses into GlobalAddress. This must make sure to copy the contents of
531 /// their initializers into the memory.
533 void ExecutionEngine::emitGlobals() {
534 const TargetData &TD = getTargetData();
536 // Loop over all of the global variables in the program, allocating the memory
538 Module &M = getModule();
539 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
541 if (!I->isExternal()) {
542 // Get the type of the global...
543 const Type *Ty = I->getType()->getElementType();
545 // Allocate some memory for it!
546 unsigned Size = TD.getTypeSize(Ty);
547 addGlobalMapping(I, new char[Size]);
549 // External variable reference. Try to use the dynamic loader to
550 // get a pointer to it.
551 if (void *SymAddr = sys::DynamicLibrary::SearchForAddressOfSymbol(
552 I->getName().c_str()))
553 addGlobalMapping(I, SymAddr);
555 std::cerr << "Could not resolve external global address: "
556 << I->getName() << "\n";
561 // Now that all of the globals are set up in memory, loop through them all and
562 // initialize their contents.
563 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
565 if (!I->isExternal())
566 EmitGlobalVariable(I);
569 // EmitGlobalVariable - This method emits the specified global variable to the
570 // address specified in GlobalAddresses, or allocates new memory if it's not
571 // already in the map.
572 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) {
573 void *GA = getPointerToGlobalIfAvailable(GV);
574 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n");
576 const Type *ElTy = GV->getType()->getElementType();
577 size_t GVSize = (size_t)getTargetData().getTypeSize(ElTy);
579 // If it's not already specified, allocate memory for the global.
580 GA = new char[GVSize];
581 addGlobalMapping(GV, GA);
584 InitializeMemory(GV->getInitializer(), GA);
585 NumInitBytes += (unsigned)GVSize;