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Diffstat (limited to 'contrib/llvm/lib/ExecutionEngine/JIT/JIT.cpp')
| -rw-r--r-- | contrib/llvm/lib/ExecutionEngine/JIT/JIT.cpp | 794 |
1 files changed, 794 insertions, 0 deletions
diff --git a/contrib/llvm/lib/ExecutionEngine/JIT/JIT.cpp b/contrib/llvm/lib/ExecutionEngine/JIT/JIT.cpp new file mode 100644 index 0000000..546d2b2 --- /dev/null +++ b/contrib/llvm/lib/ExecutionEngine/JIT/JIT.cpp @@ -0,0 +1,794 @@ +//===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This tool implements a just-in-time compiler for LLVM, allowing direct +// execution of LLVM bitcode in an efficient manner. +// +//===----------------------------------------------------------------------===// + +#include "JIT.h" +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Function.h" +#include "llvm/GlobalVariable.h" +#include "llvm/Instructions.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/CodeGen/JITCodeEmitter.h" +#include "llvm/CodeGen/MachineCodeInfo.h" +#include "llvm/ExecutionEngine/GenericValue.h" +#include "llvm/ExecutionEngine/JITEventListener.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetJITInfo.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/MutexGuard.h" +#include "llvm/System/DynamicLibrary.h" +#include "llvm/Config/config.h" + +using namespace llvm; + +#ifdef __APPLE__ +// Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead +// of atexit). It passes the address of linker generated symbol __dso_handle +// to the function. +// This configuration change happened at version 5330. +# include <AvailabilityMacros.h> +# if defined(MAC_OS_X_VERSION_10_4) && \ + ((MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4) || \ + (MAC_OS_X_VERSION_MIN_REQUIRED == MAC_OS_X_VERSION_10_4 && \ + __APPLE_CC__ >= 5330)) +# ifndef HAVE___DSO_HANDLE +# define HAVE___DSO_HANDLE 1 +# endif +# endif +#endif + +#if HAVE___DSO_HANDLE +extern void *__dso_handle __attribute__ ((__visibility__ ("hidden"))); +#endif + +namespace { + +static struct RegisterJIT { + RegisterJIT() { JIT::Register(); } +} JITRegistrator; + +} + +extern "C" void LLVMLinkInJIT() { +} + + +#if defined(__GNUC__) && !defined(__ARM__EABI__) + +// libgcc defines the __register_frame function to dynamically register new +// dwarf frames for exception handling. This functionality is not portable +// across compilers and is only provided by GCC. We use the __register_frame +// function here so that code generated by the JIT cooperates with the unwinding +// runtime of libgcc. When JITting with exception handling enable, LLVM +// generates dwarf frames and registers it to libgcc with __register_frame. +// +// The __register_frame function works with Linux. +// +// Unfortunately, this functionality seems to be in libgcc after the unwinding +// library of libgcc for darwin was written. The code for darwin overwrites the +// value updated by __register_frame with a value fetched with "keymgr". +// "keymgr" is an obsolete functionality, which should be rewritten some day. +// In the meantime, since "keymgr" is on all libgccs shipped with apple-gcc, we +// need a workaround in LLVM which uses the "keymgr" to dynamically modify the +// values of an opaque key, used by libgcc to find dwarf tables. + +extern "C" void __register_frame(void*); + +#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050 +# define USE_KEYMGR 1 +#else +# define USE_KEYMGR 0 +#endif + +#if USE_KEYMGR + +namespace { + +// LibgccObject - This is the structure defined in libgcc. There is no #include +// provided for this structure, so we also define it here. libgcc calls it +// "struct object". The structure is undocumented in libgcc. +struct LibgccObject { + void *unused1; + void *unused2; + void *unused3; + + /// frame - Pointer to the exception table. + void *frame; + + /// encoding - The encoding of the object? + union { + struct { + unsigned long sorted : 1; + unsigned long from_array : 1; + unsigned long mixed_encoding : 1; + unsigned long encoding : 8; + unsigned long count : 21; + } b; + size_t i; + } encoding; + + /// fde_end - libgcc defines this field only if some macro is defined. We + /// include this field even if it may not there, to make libgcc happy. + char *fde_end; + + /// next - At least we know it's a chained list! + struct LibgccObject *next; +}; + +// "kemgr" stuff. Apparently, all frame tables are stored there. +extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *); +extern "C" void *_keymgr_get_and_lock_processwide_ptr(int); +#define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */ + +/// LibgccObjectInfo - libgcc defines this struct as km_object_info. It +/// probably contains all dwarf tables that are loaded. +struct LibgccObjectInfo { + + /// seenObjects - LibgccObjects already parsed by the unwinding runtime. + /// + struct LibgccObject* seenObjects; + + /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime. + /// + struct LibgccObject* unseenObjects; + + unsigned unused[2]; +}; + +/// darwin_register_frame - Since __register_frame does not work with darwin's +/// libgcc,we provide our own function, which "tricks" libgcc by modifying the +/// "Dwarf2 object list" key. +void DarwinRegisterFrame(void* FrameBegin) { + // Get the key. + LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) + _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); + assert(LOI && "This should be preallocated by the runtime"); + + // Allocate a new LibgccObject to represent this frame. Deallocation of this + // object may be impossible: since darwin code in libgcc was written after + // the ability to dynamically register frames, things may crash if we + // deallocate it. + struct LibgccObject* ob = (struct LibgccObject*) + malloc(sizeof(struct LibgccObject)); + + // Do like libgcc for the values of the field. + ob->unused1 = (void *)-1; + ob->unused2 = 0; + ob->unused3 = 0; + ob->frame = FrameBegin; + ob->encoding.i = 0; + ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit; + + // Put the info on both places, as libgcc uses the first or the second + // field. Note that we rely on having two pointers here. If fde_end was a + // char, things would get complicated. + ob->fde_end = (char*)LOI->unseenObjects; + ob->next = LOI->unseenObjects; + + // Update the key's unseenObjects list. + LOI->unseenObjects = ob; + + // Finally update the "key". Apparently, libgcc requires it. + _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, + LOI); + +} + +} +#endif // __APPLE__ +#endif // __GNUC__ + +/// createJIT - This is the factory method for creating a JIT for the current +/// machine, it does not fall back to the interpreter. This takes ownership +/// of the module. +ExecutionEngine *ExecutionEngine::createJIT(Module *M, + std::string *ErrorStr, + JITMemoryManager *JMM, + CodeGenOpt::Level OptLevel, + bool GVsWithCode, + CodeModel::Model CMM) { + // Use the defaults for extra parameters. Users can use EngineBuilder to + // set them. + StringRef MArch = ""; + StringRef MCPU = ""; + SmallVector<std::string, 1> MAttrs; + return JIT::createJIT(M, ErrorStr, JMM, OptLevel, GVsWithCode, CMM, + MArch, MCPU, MAttrs); +} + +ExecutionEngine *JIT::createJIT(Module *M, + std::string *ErrorStr, + JITMemoryManager *JMM, + CodeGenOpt::Level OptLevel, + bool GVsWithCode, + CodeModel::Model CMM, + StringRef MArch, + StringRef MCPU, + const SmallVectorImpl<std::string>& MAttrs) { + // 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; + + // Pick a target either via -march or by guessing the native arch. + TargetMachine *TM = JIT::selectTarget(M, MArch, MCPU, MAttrs, ErrorStr); + if (!TM || (ErrorStr && ErrorStr->length() > 0)) return 0; + TM->setCodeModel(CMM); + + // If the target supports JIT code generation, create a the JIT. + if (TargetJITInfo *TJ = TM->getJITInfo()) { + return new JIT(M, *TM, *TJ, JMM, OptLevel, GVsWithCode); + } else { + if (ErrorStr) + *ErrorStr = "target does not support JIT code generation"; + return 0; + } +} + +namespace { +/// This class supports the global getPointerToNamedFunction(), which allows +/// bugpoint or gdb users to search for a function by name without any context. +class JitPool { + SmallPtrSet<JIT*, 1> JITs; // Optimize for process containing just 1 JIT. + mutable sys::Mutex Lock; +public: + void Add(JIT *jit) { + MutexGuard guard(Lock); + JITs.insert(jit); + } + void Remove(JIT *jit) { + MutexGuard guard(Lock); + JITs.erase(jit); + } + void *getPointerToNamedFunction(const char *Name) const { + MutexGuard guard(Lock); + assert(JITs.size() != 0 && "No Jit registered"); + //search function in every instance of JIT + for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(), + end = JITs.end(); + Jit != end; ++Jit) { + if (Function *F = (*Jit)->FindFunctionNamed(Name)) + return (*Jit)->getPointerToFunction(F); + } + // The function is not available : fallback on the first created (will + // search in symbol of the current program/library) + return (*JITs.begin())->getPointerToNamedFunction(Name); + } +}; +ManagedStatic<JitPool> AllJits; +} +extern "C" { + // getPointerToNamedFunction - This function is used as a global wrapper to + // JIT::getPointerToNamedFunction for the purpose of resolving symbols when + // bugpoint is debugging the JIT. In that scenario, we are loading an .so and + // need to resolve function(s) that are being mis-codegenerated, so we need to + // resolve their addresses at runtime, and this is the way to do it. + void *getPointerToNamedFunction(const char *Name) { + return AllJits->getPointerToNamedFunction(Name); + } +} + +JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji, + JITMemoryManager *JMM, CodeGenOpt::Level OptLevel, bool GVsWithCode) + : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode), + isAlreadyCodeGenerating(false) { + setTargetData(TM.getTargetData()); + + jitstate = new JITState(M); + + // Initialize JCE + JCE = createEmitter(*this, JMM, TM); + + // Register in global list of all JITs. + AllJits->Add(this); + + // Add target data + MutexGuard locked(lock); + FunctionPassManager &PM = jitstate->getPM(locked); + PM.add(new TargetData(*TM.getTargetData())); + + // Turn the machine code intermediate representation into bytes in memory that + // may be executed. + if (TM.addPassesToEmitMachineCode(PM, *JCE, OptLevel)) { + report_fatal_error("Target does not support machine code emission!"); + } + + // Register routine for informing unwinding runtime about new EH frames +#if defined(__GNUC__) && !defined(__ARM_EABI__) +#if USE_KEYMGR + struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) + _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); + + // The key is created on demand, and libgcc creates it the first time an + // exception occurs. Since we need the key to register frames, we create + // it now. + if (!LOI) + LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1); + _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI); + InstallExceptionTableRegister(DarwinRegisterFrame); +#else + InstallExceptionTableRegister(__register_frame); +#endif // __APPLE__ +#endif // __GNUC__ + + // Initialize passes. + PM.doInitialization(); +} + +JIT::~JIT() { + AllJits->Remove(this); + delete jitstate; + delete JCE; + delete &TM; +} + +/// addModule - Add a new Module to the JIT. If we previously removed the last +/// Module, we need re-initialize jitstate with a valid Module. +void JIT::addModule(Module *M) { + MutexGuard locked(lock); + + if (Modules.empty()) { + assert(!jitstate && "jitstate should be NULL if Modules vector is empty!"); + + jitstate = new JITState(M); + + FunctionPassManager &PM = jitstate->getPM(locked); + PM.add(new TargetData(*TM.getTargetData())); + + // Turn the machine code intermediate representation into bytes in memory + // that may be executed. + if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) { + report_fatal_error("Target does not support machine code emission!"); + } + + // Initialize passes. + PM.doInitialization(); + } + + ExecutionEngine::addModule(M); +} + +/// removeModule - If we are removing the last Module, invalidate the jitstate +/// since the PassManager it contains references a released Module. +bool JIT::removeModule(Module *M) { + bool result = ExecutionEngine::removeModule(M); + + MutexGuard locked(lock); + + if (jitstate->getModule() == M) { + delete jitstate; + jitstate = 0; + } + + if (!jitstate && !Modules.empty()) { + jitstate = new JITState(Modules[0]); + + FunctionPassManager &PM = jitstate->getPM(locked); + PM.add(new TargetData(*TM.getTargetData())); + + // Turn the machine code intermediate representation into bytes in memory + // that may be executed. + if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) { + report_fatal_error("Target does not support machine code emission!"); + } + + // Initialize passes. + PM.doInitialization(); + } + return result; +} + +/// run - Start execution with the specified function and arguments. +/// +GenericValue JIT::runFunction(Function *F, + const std::vector<GenericValue> &ArgValues) { + assert(F && "Function *F was null at entry to run()"); + + void *FPtr = getPointerToFunction(F); + assert(FPtr && "Pointer to fn's code was null after getPointerToFunction"); + const FunctionType *FTy = F->getFunctionType(); + const Type *RetTy = FTy->getReturnType(); + + assert((FTy->getNumParams() == ArgValues.size() || + (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) && + "Wrong number of arguments passed into function!"); + assert(FTy->getNumParams() == ArgValues.size() && + "This doesn't support passing arguments through varargs (yet)!"); + + // Handle some common cases first. These cases correspond to common `main' + // prototypes. + if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) { + switch (ArgValues.size()) { + case 3: + if (FTy->getParamType(0)->isIntegerTy(32) && + FTy->getParamType(1)->isPointerTy() && + FTy->getParamType(2)->isPointerTy()) { + int (*PF)(int, char **, const char **) = + (int(*)(int, char **, const char **))(intptr_t)FPtr; + + // Call the function. + GenericValue rv; + rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), + (char **)GVTOP(ArgValues[1]), + (const char **)GVTOP(ArgValues[2]))); + return rv; + } + break; + case 2: + if (FTy->getParamType(0)->isIntegerTy(32) && + FTy->getParamType(1)->isPointerTy()) { + int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr; + + // Call the function. + GenericValue rv; + rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), + (char **)GVTOP(ArgValues[1]))); + return rv; + } + break; + case 1: + if (FTy->getNumParams() == 1 && + FTy->getParamType(0)->isIntegerTy(32)) { + GenericValue rv; + int (*PF)(int) = (int(*)(int))(intptr_t)FPtr; + rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue())); + return rv; + } + break; + } + } + + // Handle cases where no arguments are passed first. + if (ArgValues.empty()) { + GenericValue rv; + switch (RetTy->getTypeID()) { + default: llvm_unreachable("Unknown return type for function call!"); + case Type::IntegerTyID: { + unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth(); + if (BitWidth == 1) + rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)()); + else if (BitWidth <= 8) + rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)()); + else if (BitWidth <= 16) + rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)()); + else if (BitWidth <= 32) + rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)()); + else if (BitWidth <= 64) + rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)()); + else + llvm_unreachable("Integer types > 64 bits not supported"); + return rv; + } + case Type::VoidTyID: + rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)()); + return rv; + case Type::FloatTyID: + rv.FloatVal = ((float(*)())(intptr_t)FPtr)(); + return rv; + case Type::DoubleTyID: + rv.DoubleVal = ((double(*)())(intptr_t)FPtr)(); + return rv; + case Type::X86_FP80TyID: + case Type::FP128TyID: + case Type::PPC_FP128TyID: + llvm_unreachable("long double not supported yet"); + return rv; + case Type::PointerTyID: + return PTOGV(((void*(*)())(intptr_t)FPtr)()); + } + } + + // Okay, this is not one of our quick and easy cases. Because we don't have a + // full FFI, we have to codegen a nullary stub function that just calls the + // function we are interested in, passing in constants for all of the + // arguments. Make this function and return. + + // First, create the function. + FunctionType *STy=FunctionType::get(RetTy, false); + Function *Stub = Function::Create(STy, Function::InternalLinkage, "", + F->getParent()); + + // Insert a basic block. + BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub); + + // Convert all of the GenericValue arguments over to constants. Note that we + // currently don't support varargs. + SmallVector<Value*, 8> Args; + for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) { + Constant *C = 0; + const Type *ArgTy = FTy->getParamType(i); + const GenericValue &AV = ArgValues[i]; + switch (ArgTy->getTypeID()) { + default: llvm_unreachable("Unknown argument type for function call!"); + case Type::IntegerTyID: + C = ConstantInt::get(F->getContext(), AV.IntVal); + break; + case Type::FloatTyID: + C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal)); + break; + case Type::DoubleTyID: + C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal)); + break; + case Type::PPC_FP128TyID: + case Type::X86_FP80TyID: + case Type::FP128TyID: + C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal)); + break; + case Type::PointerTyID: + void *ArgPtr = GVTOP(AV); + if (sizeof(void*) == 4) + C = ConstantInt::get(Type::getInt32Ty(F->getContext()), + (int)(intptr_t)ArgPtr); + else + C = ConstantInt::get(Type::getInt64Ty(F->getContext()), + (intptr_t)ArgPtr); + // Cast the integer to pointer + C = ConstantExpr::getIntToPtr(C, ArgTy); + break; + } + Args.push_back(C); + } + + CallInst *TheCall = CallInst::Create(F, Args.begin(), Args.end(), + "", StubBB); + TheCall->setCallingConv(F->getCallingConv()); + TheCall->setTailCall(); + if (!TheCall->getType()->isVoidTy()) + // Return result of the call. + ReturnInst::Create(F->getContext(), TheCall, StubBB); + else + ReturnInst::Create(F->getContext(), StubBB); // Just return void. + + // Finally, call our nullary stub function. + GenericValue Result = runFunction(Stub, std::vector<GenericValue>()); + // Erase it, since no other function can have a reference to it. + Stub->eraseFromParent(); + // And return the result. + return Result; +} + +void JIT::RegisterJITEventListener(JITEventListener *L) { + if (L == NULL) + return; + MutexGuard locked(lock); + EventListeners.push_back(L); +} +void JIT::UnregisterJITEventListener(JITEventListener *L) { + if (L == NULL) + return; + MutexGuard locked(lock); + std::vector<JITEventListener*>::reverse_iterator I= + std::find(EventListeners.rbegin(), EventListeners.rend(), L); + if (I != EventListeners.rend()) { + std::swap(*I, EventListeners.back()); + EventListeners.pop_back(); + } +} +void JIT::NotifyFunctionEmitted( + const Function &F, + void *Code, size_t Size, + const JITEvent_EmittedFunctionDetails &Details) { + MutexGuard locked(lock); + for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { + EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details); + } +} + +void JIT::NotifyFreeingMachineCode(void *OldPtr) { + MutexGuard locked(lock); + for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { + EventListeners[I]->NotifyFreeingMachineCode(OldPtr); + } +} + +/// runJITOnFunction - Run the FunctionPassManager full of +/// just-in-time compilation passes on F, hopefully filling in +/// GlobalAddress[F] with the address of F's machine code. +/// +void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) { + MutexGuard locked(lock); + + class MCIListener : public JITEventListener { + MachineCodeInfo *const MCI; + public: + MCIListener(MachineCodeInfo *mci) : MCI(mci) {} + virtual void NotifyFunctionEmitted(const Function &, + void *Code, size_t Size, + const EmittedFunctionDetails &) { + MCI->setAddress(Code); + MCI->setSize(Size); + } + }; + MCIListener MCIL(MCI); + if (MCI) + RegisterJITEventListener(&MCIL); + + runJITOnFunctionUnlocked(F, locked); + + if (MCI) + UnregisterJITEventListener(&MCIL); +} + +void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) { + assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"); + + // JIT the function + isAlreadyCodeGenerating = true; + jitstate->getPM(locked).run(*F); + isAlreadyCodeGenerating = false; + + // If the function referred to another function that had not yet been + // read from bitcode, and we are jitting non-lazily, emit it now. + while (!jitstate->getPendingFunctions(locked).empty()) { + Function *PF = jitstate->getPendingFunctions(locked).back(); + jitstate->getPendingFunctions(locked).pop_back(); + + assert(!PF->hasAvailableExternallyLinkage() && + "Externally-defined function should not be in pending list."); + + // JIT the function + isAlreadyCodeGenerating = true; + jitstate->getPM(locked).run(*PF); + isAlreadyCodeGenerating = false; + + // Now that the function has been jitted, ask the JITEmitter to rewrite + // the stub with real address of the function. + updateFunctionStub(PF); + } +} + +/// getPointerToFunction - This method is used to get the address of the +/// specified function, compiling it if neccesary. +/// +void *JIT::getPointerToFunction(Function *F) { + + if (void *Addr = getPointerToGlobalIfAvailable(F)) + return Addr; // Check if function already code gen'd + + MutexGuard locked(lock); + + // Now that this thread owns the lock, make sure we read in the function if it + // exists in this Module. + std::string ErrorMsg; + if (F->Materialize(&ErrorMsg)) { + report_fatal_error("Error reading function '" + F->getName()+ + "' from bitcode file: " + ErrorMsg); + } + + // ... and check if another thread has already code gen'd the function. + if (void *Addr = getPointerToGlobalIfAvailable(F)) + return Addr; + + if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) { + bool AbortOnFailure = !F->hasExternalWeakLinkage(); + void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure); + addGlobalMapping(F, Addr); + return Addr; + } + + runJITOnFunctionUnlocked(F, locked); + + void *Addr = getPointerToGlobalIfAvailable(F); + assert(Addr && "Code generation didn't add function to GlobalAddress table!"); + return Addr; +} + +/// getOrEmitGlobalVariable - Return the address of the specified global +/// variable, possibly emitting it to memory if needed. This is used by the +/// Emitter. +void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) { + MutexGuard locked(lock); + + void *Ptr = getPointerToGlobalIfAvailable(GV); + if (Ptr) return Ptr; + + // If the global is external, just remember the address. + if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) { +#if HAVE___DSO_HANDLE + if (GV->getName() == "__dso_handle") + return (void*)&__dso_handle; +#endif + Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName()); + if (Ptr == 0) { + report_fatal_error("Could not resolve external global address: " + +GV->getName()); + } + addGlobalMapping(GV, Ptr); + } else { + // If the global hasn't been emitted to memory yet, allocate space and + // emit it into memory. + Ptr = getMemoryForGV(GV); + addGlobalMapping(GV, Ptr); + EmitGlobalVariable(GV); // Initialize the variable. + } + return Ptr; +} + +/// recompileAndRelinkFunction - This method is used to force a function +/// which has already been compiled, to be compiled again, possibly +/// after it has been modified. Then the entry to the old copy is overwritten +/// with a branch to the new copy. If there was no old copy, this acts +/// just like JIT::getPointerToFunction(). +/// +void *JIT::recompileAndRelinkFunction(Function *F) { + void *OldAddr = getPointerToGlobalIfAvailable(F); + + // If it's not already compiled there is no reason to patch it up. + if (OldAddr == 0) { return getPointerToFunction(F); } + + // Delete the old function mapping. + addGlobalMapping(F, 0); + + // Recodegen the function + runJITOnFunction(F); + + // Update state, forward the old function to the new function. + void *Addr = getPointerToGlobalIfAvailable(F); + assert(Addr && "Code generation didn't add function to GlobalAddress table!"); + TJI.replaceMachineCodeForFunction(OldAddr, Addr); + return Addr; +} + +/// getMemoryForGV - This method abstracts memory allocation of global +/// variable so that the JIT can allocate thread local variables depending +/// on the target. +/// +char* JIT::getMemoryForGV(const GlobalVariable* GV) { + char *Ptr; + + // GlobalVariable's which are not "constant" will cause trouble in a server + // situation. It's returned in the same block of memory as code which may + // not be writable. + if (isGVCompilationDisabled() && !GV->isConstant()) { + report_fatal_error("Compilation of non-internal GlobalValue is disabled!"); + } + + // Some applications require globals and code to live together, so they may + // be allocated into the same buffer, but in general globals are allocated + // through the memory manager which puts them near the code but not in the + // same buffer. + const Type *GlobalType = GV->getType()->getElementType(); + size_t S = getTargetData()->getTypeAllocSize(GlobalType); + size_t A = getTargetData()->getPreferredAlignment(GV); + if (GV->isThreadLocal()) { + MutexGuard locked(lock); + Ptr = TJI.allocateThreadLocalMemory(S); + } else if (TJI.allocateSeparateGVMemory()) { + if (A <= 8) { + Ptr = (char*)malloc(S); + } else { + // Allocate S+A bytes of memory, then use an aligned pointer within that + // space. + Ptr = (char*)malloc(S+A); + unsigned MisAligned = ((intptr_t)Ptr & (A-1)); + Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0); + } + } else if (AllocateGVsWithCode) { + Ptr = (char*)JCE->allocateSpace(S, A); + } else { + Ptr = (char*)JCE->allocateGlobal(S, A); + } + return Ptr; +} + +void JIT::addPendingFunction(Function *F) { + MutexGuard locked(lock); + jitstate->getPendingFunctions(locked).push_back(F); +} + + +JITEventListener::~JITEventListener() {} |
