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Diffstat (limited to 'llvm/include/MCJITMemoryManager.h')
| -rw-r--r-- | llvm/include/MCJITMemoryManager.h | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/llvm/include/MCJITMemoryManager.h b/llvm/include/MCJITMemoryManager.h new file mode 100644 index 0000000..33059a5 --- /dev/null +++ b/llvm/include/MCJITMemoryManager.h @@ -0,0 +1,213 @@ +//===-- MCJITMemoryManager.cpp - Memory manager for MC-JIT -----*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Interface of the MCJIT memory manager base class. +// +//===----------------------------------------------------------------------===// + +#ifndef __MCJITMEMORYMANAGER_H +#define __MCJITMEMORYMANAGER_H + +#include "llvm/ExecutionEngine/RTDyldMemoryManager.h" +#include "llvm-debug.h" +#include "utils.h" + +using namespace llvm; + +#define MIN_CODE_CACHE_SIZE (1 * 1024 * 1024) +#define DEFAULT_GLOBAL_SIZE (64 * 1024) +#define DEFAULT_THRESHOLD (32 * 1024) + +// RuntimeDyld clients often want to handle the memory management of +// what gets placed where. For JIT clients, this is the subset of +// JITMemoryManager required for dynamic loading of binaries. +// +// FIXME: As the RuntimeDyld fills out, additional routines will be needed +// for the varying types of objects to be allocated. +class DefaultMCJITMemoryManager : public RTDyldMemoryManager { + uint8_t *TraceCache; + size_t TraceCacheSize; + + uint8_t *GlobalBase; /* section for global data used by QEMU helpers */ + uint8_t *CodeBase; /* section for emitting trace code */ + uint8_t *CodeGenPtr; + + size_t GlobalRemain; + size_t CodeRemain; + size_t Threshold; + + hqemu::Mutex lock; + + SymbolMap Symbols; + +public: + DefaultMCJITMemoryManager(uint8_t *Cache, size_t Size) + : TraceCache(Cache), TraceCacheSize(Size), Threshold(DEFAULT_THRESHOLD) + { + GlobalBase = TraceCache; + GlobalRemain = DEFAULT_GLOBAL_SIZE; + + CodeBase = GlobalBase + DEFAULT_GLOBAL_SIZE; + CodeBase = (uint8_t *)(((uintptr_t)CodeBase + CODE_GEN_ALIGN - 1) & ~(CODE_GEN_ALIGN - 1)); + CodeRemain = (uintptr_t)TraceCache + TraceCacheSize - (uintptr_t)CodeBase; + CodeGenPtr = CodeBase; + } + ~DefaultMCJITMemoryManager() {} + + /// Allocate a memory block of (at least) the given size suitable for + /// executable code. The SectionID is a unique identifier assigned by the JIT + /// engine, and optionally recorded by the memory manager to access a loaded + /// section. + uint8_t *allocateCodeSection( + uintptr_t Size, unsigned Alignment, unsigned SectionID, + StringRef SectionName) override { + hqemu::MutexGuard locked(lock); + + if (!Alignment) + Alignment = 16; + + if (Alignment & (Alignment - 1)) + hqemu_error("Alignment must be a power of two.\n"); + + uintptr_t CurGenPtr = (uintptr_t)CodeGenPtr; + CurGenPtr = (CurGenPtr + Alignment - 1) & ~(uintptr_t)(Alignment - 1); + CodeGenPtr = (uint8_t *)((CurGenPtr + Size + CODE_GEN_ALIGN - 1) & + ~(uintptr_t)(CODE_GEN_ALIGN - 1)); + CodeRemain = (uintptr_t)TraceCache + TraceCacheSize - (uintptr_t)CodeGenPtr; + return (uint8_t *)CurGenPtr; + } + + /// Allocate a memory block of (at least) the given size suitable for data. + /// The SectionID is a unique identifier assigned by the JIT engine, and + /// optionally recorded by the memory manager to access a loaded section. + uint8_t *allocateDataSection( + uintptr_t Size, unsigned Alignment, unsigned SectionID, + StringRef SectionName, bool IsReadOnly) override { + return allocateCodeSection(Size, Alignment, SectionID, SectionName); + } + + /// Inform the memory manager about the total amount of memory required to + /// allocate all sections to be loaded: + /// \p CodeSize - the total size of all code sections + /// \p DataSizeRO - the total size of all read-only data sections + /// \p DataSizeRW - the total size of all read-write data sections + /// + /// Note that by default the callback is disabled. To enable it + /// redefine the method needsToReserveAllocationSpace to return true. + void reserveAllocationSpace( + uintptr_t CodeSize, uintptr_t DataSizeRO, uintptr_t DataSizeRW) { + hqemu_error("fixme.\n"); + } + + /// Override to return true to enable the reserveAllocationSpace callback. + bool needsToReserveAllocationSpace() { return false; } + + /// Register the EH frames with the runtime so that c++ exceptions work. + /// + /// \p Addr parameter provides the local address of the EH frame section + /// data, while \p LoadAddr provides the address of the data in the target + /// address space. If the section has not been remapped (which will usually + /// be the case for local execution) these two values will be the same. + void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size) { + hqemu_error("fixme.\n"); + } + + void deregisterEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size) { + hqemu_error("fixme.\n"); + } + + /// This method returns the address of the specified function or variable. + /// It is used to resolve symbols during module linking. + uint64_t getSymbolAddress(const std::string &Name) { + hqemu::MutexGuard locked(lock); + if (Symbols.find(Name) == Symbols.end()) { + std::string ErrMsg = "Program used external symbol '" + Name + + "'which could not be resolved!\n"; + hqemu_error(ErrMsg.c_str()); + } + return Symbols[Name]; + } + + /// This method returns the address of the specified function. As such it is + /// only useful for resolving library symbols, not code generated symbols. + /// + /// If \p AbortOnFailure is false and no function with the given name is + /// found, this function returns a null pointer. Otherwise, it prints a + /// message to stderr and aborts. + /// + /// This function is deprecated for memory managers to be used with + /// MCJIT or RuntimeDyld. Use getSymbolAddress instead. + void *getPointerToNamedFunction(const std::string &Name, + bool AbortOnFailure = true) { + if (AbortOnFailure) { + std::string ErrMsg = "Program used external symbol '" + Name + + "'which could not be resolved!\n"; + hqemu_error(ErrMsg.c_str()); + } + return nullptr; + } + + /// This method is called after an object has been loaded into memory but + /// before relocations are applied to the loaded sections. The object load + /// may have been initiated by MCJIT to resolve an external symbol for another + /// object that is being finalized. In that case, the object about which + /// the memory manager is being notified will be finalized immediately after + /// the memory manager returns from this call. + /// + /// Memory managers which are preparing code for execution in an external + /// address space can use this call to remap the section addresses for the + /// newly loaded object. +#if defined(LLVM_V35) + void notifyObjectLoaded(ExecutionEngine *EE, + const ObjectImage *Obj) { + } +#else + void notifyObjectLoaded(RuntimeDyld &RTDyld, + const object::ObjectFile &Obj) { + } +#endif + + /// This method is called when object loading is complete and section page + /// permissions can be applied. It is up to the memory manager implementation + /// to decide whether or not to act on this method. The memory manager will + /// typically allocate all sections as read-write and then apply specific + /// permissions when this method is called. Code sections cannot be executed + /// until this function has been called. In addition, any cache coherency + /// operations needed to reliably use the memory are also performed. + /// + /// Returns true if an error occurred, false otherwise. + bool finalizeMemory(std::string *ErrMsg = nullptr) override { + return false; + } + + void AddSymbols(SymbolMap &symbols) { + Symbols = symbols; + } + + size_t getCodeSize() { return CodeGenPtr - CodeBase; } + bool isSizeAvailable() { + hqemu::MutexGuard locked(lock); + return CodeRemain >= Threshold ? 1 : 0; + } + void Flush() { + CodeGenPtr = CodeBase; + CodeRemain = (uintptr_t)TraceCache + TraceCacheSize - (uintptr_t)CodeBase; + } + + static DefaultMCJITMemoryManager *Create(uint8_t *Cache, size_t Size) { + if (Size < MIN_CODE_CACHE_SIZE) { + std::string ErrMsg = "Trace cache size is too small (" + + std::to_string(Size) + ")\n."; + hqemu_error(ErrMsg.c_str()); + } + return new DefaultMCJITMemoryManager(Cache, Size); + } +}; + +#endif |
