1 //===- RemoteTarget.cpp - LLVM Remote process JIT execution --------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // Implementation of the RemoteTarget class which executes JITed code in a 11 // separate address range from where it was built. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "RemoteTarget.h" 16 #include "llvm/ADT/StringRef.h" 17 #include "llvm/Support/DataTypes.h" 18 #include "llvm/Support/Memory.h" 19 #include <stdlib.h> 20 #include <string> 21 22 using namespace llvm; 23 24 //////////////////////////////////////////////////////////////////////////////// 25 // Simulated remote execution 26 // 27 // This implementation will simply move generated code and data to a new memory 28 // location in the current executable and let it run from there. 29 //////////////////////////////////////////////////////////////////////////////// 30 31 bool RemoteTarget::allocateSpace(size_t Size, unsigned Alignment, 32 uint64_t &Address) { 33 sys::MemoryBlock *Prev = Allocations.size() ? &Allocations.back() : nullptr; 34 sys::MemoryBlock Mem = sys::Memory::AllocateRWX(Size, Prev, &ErrorMsg); 35 if (Mem.base() == nullptr) 36 return false; 37 if ((uintptr_t)Mem.base() % Alignment) { 38 ErrorMsg = "unable to allocate sufficiently aligned memory"; 39 return false; 40 } 41 Address = reinterpret_cast<uint64_t>(Mem.base()); 42 Allocations.push_back(Mem); 43 return true; 44 } 45 46 bool RemoteTarget::loadData(uint64_t Address, const void *Data, size_t Size) { 47 memcpy ((void*)Address, Data, Size); 48 return true; 49 } 50 51 bool RemoteTarget::loadCode(uint64_t Address, const void *Data, size_t Size) { 52 memcpy ((void*)Address, Data, Size); 53 sys::MemoryBlock Mem((void*)Address, Size); 54 sys::Memory::setExecutable(Mem, &ErrorMsg); 55 return true; 56 } 57 58 bool RemoteTarget::executeCode(uint64_t Address, int &RetVal) { 59 int (*fn)(void) = (int(*)(void))Address; 60 RetVal = fn(); 61 return true; 62 } 63 64 bool RemoteTarget::create() { 65 return true; 66 } 67 68 void RemoteTarget::stop() { 69 for (unsigned i = 0, e = Allocations.size(); i != e; ++i) 70 sys::Memory::ReleaseRWX(Allocations[i]); 71 } 72