llvm-rtdyld.cpp revision 263508 
1//===-- llvm-rtdyld.cpp - MCJIT Testing Tool ------------------------------===//
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// This is a testing tool for use with the MC-JIT LLVM components.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/ADT/OwningPtr.h"
15#include "llvm/ADT/StringMap.h"
16#include "llvm/DebugInfo/DIContext.h"
17#include "llvm/ExecutionEngine/ObjectBuffer.h"
18#include "llvm/ExecutionEngine/ObjectImage.h"
19#include "llvm/ExecutionEngine/RuntimeDyld.h"
20#include "llvm/Object/MachO.h"
21#include "llvm/Support/CommandLine.h"
22#include "llvm/Support/ManagedStatic.h"
23#include "llvm/Support/Memory.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include "llvm/Support/PrettyStackTrace.h"
26#include "llvm/Support/Signals.h"
27#include "llvm/Support/raw_ostream.h"
28#include "llvm/Support/system_error.h"
29using namespace llvm;
30using namespace llvm::object;
31
32static cl::list<std::string>
33InputFileList(cl::Positional, cl::ZeroOrMore,
34              cl::desc("<input file>"));
35
36enum ActionType {
37  AC_Execute,
38  AC_PrintLineInfo
39};
40
41static cl::opt<ActionType>
42Action(cl::desc("Action to perform:"),
43       cl::init(AC_Execute),
44       cl::values(clEnumValN(AC_Execute, "execute",
45                             "Load, link, and execute the inputs."),
46                  clEnumValN(AC_PrintLineInfo, "printline",
47                             "Load, link, and print line information for each function."),
48                  clEnumValEnd));
49
50static cl::opt<std::string>
51EntryPoint("entry",
52           cl::desc("Function to call as entry point."),
53           cl::init("_main"));
54
55/* *** */
56
57// A trivial memory manager that doesn't do anything fancy, just uses the
58// support library allocation routines directly.
59class TrivialMemoryManager : public RTDyldMemoryManager {
60public:
61  SmallVector<sys::MemoryBlock, 16> FunctionMemory;
62  SmallVector<sys::MemoryBlock, 16> DataMemory;
63
64  uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
65                               unsigned SectionID, StringRef SectionName);
66  uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
67                               unsigned SectionID, StringRef SectionName,
68                               bool IsReadOnly);
69
70  virtual void *getPointerToNamedFunction(const std::string &Name,
71                                          bool AbortOnFailure = true) {
72    return 0;
73  }
74
75  bool finalizeMemory(std::string *ErrMsg) { return false; }
76
77  // Invalidate instruction cache for sections with execute permissions.
78  // Some platforms with separate data cache and instruction cache require
79  // explicit cache flush, otherwise JIT code manipulations (like resolved
80  // relocations) will get to the data cache but not to the instruction cache.
81  virtual void invalidateInstructionCache();
82};
83
84uint8_t *TrivialMemoryManager::allocateCodeSection(uintptr_t Size,
85                                                   unsigned Alignment,
86                                                   unsigned SectionID,
87                                                   StringRef SectionName) {
88  sys::MemoryBlock MB = sys::Memory::AllocateRWX(Size, 0, 0);
89  FunctionMemory.push_back(MB);
90  return (uint8_t*)MB.base();
91}
92
93uint8_t *TrivialMemoryManager::allocateDataSection(uintptr_t Size,
94                                                   unsigned Alignment,
95                                                   unsigned SectionID,
96                                                   StringRef SectionName,
97                                                   bool IsReadOnly) {
98  sys::MemoryBlock MB = sys::Memory::AllocateRWX(Size, 0, 0);
99  DataMemory.push_back(MB);
100  return (uint8_t*)MB.base();
101}
102
103void TrivialMemoryManager::invalidateInstructionCache() {
104  for (int i = 0, e = FunctionMemory.size(); i != e; ++i)
105    sys::Memory::InvalidateInstructionCache(FunctionMemory[i].base(),
106                                            FunctionMemory[i].size());
107
108  for (int i = 0, e = DataMemory.size(); i != e; ++i)
109    sys::Memory::InvalidateInstructionCache(DataMemory[i].base(),
110                                            DataMemory[i].size());
111}
112
113static const char *ProgramName;
114
115static void Message(const char *Type, const Twine &Msg) {
116  errs() << ProgramName << ": " << Type << ": " << Msg << "\n";
117}
118
119static int Error(const Twine &Msg) {
120  Message("error", Msg);
121  return 1;
122}
123
124/* *** */
125
126static int printLineInfoForInput() {
127  // If we don't have any input files, read from stdin.
128  if (!InputFileList.size())
129    InputFileList.push_back("-");
130  for(unsigned i = 0, e = InputFileList.size(); i != e; ++i) {
131    // Instantiate a dynamic linker.
132    TrivialMemoryManager MemMgr;
133    RuntimeDyld Dyld(&MemMgr);
134
135    // Load the input memory buffer.
136    OwningPtr<MemoryBuffer> InputBuffer;
137    OwningPtr<ObjectImage>  LoadedObject;
138    if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFileList[i],
139                                                     InputBuffer))
140      return Error("unable to read input: '" + ec.message() + "'");
141
142    // Load the object file
143    LoadedObject.reset(Dyld.loadObject(new ObjectBuffer(InputBuffer.take())));
144    if (!LoadedObject) {
145      return Error(Dyld.getErrorString());
146    }
147
148    // Resolve all the relocations we can.
149    Dyld.resolveRelocations();
150
151    OwningPtr<DIContext> Context(DIContext::getDWARFContext(LoadedObject->getObjectFile()));
152
153    // Use symbol info to iterate functions in the object.
154    error_code ec;
155    for (object::symbol_iterator I = LoadedObject->begin_symbols(),
156                                 E = LoadedObject->end_symbols();
157                          I != E && !ec;
158                          I.increment(ec)) {
159      object::SymbolRef::Type SymType;
160      if (I->getType(SymType)) continue;
161      if (SymType == object::SymbolRef::ST_Function) {
162        StringRef  Name;
163        uint64_t   Addr;
164        uint64_t   Size;
165        if (I->getName(Name)) continue;
166        if (I->getAddress(Addr)) continue;
167        if (I->getSize(Size)) continue;
168
169        outs() << "Function: " << Name << ", Size = " << Size << "\n";
170
171        DILineInfoTable Lines = Context->getLineInfoForAddressRange(Addr, Size);
172        DILineInfoTable::iterator  Begin = Lines.begin();
173        DILineInfoTable::iterator  End = Lines.end();
174        for (DILineInfoTable::iterator It = Begin; It != End; ++It) {
175          outs() << "  Line info @ " << It->first - Addr << ": "
176                 << It->second.getFileName()
177                 << ", line:" << It->second.getLine() << "\n";
178        }
179      }
180    }
181  }
182
183  return 0;
184}
185
186static int executeInput() {
187  // Instantiate a dynamic linker.
188  TrivialMemoryManager MemMgr;
189  RuntimeDyld Dyld(&MemMgr);
190
191  // If we don't have any input files, read from stdin.
192  if (!InputFileList.size())
193    InputFileList.push_back("-");
194  for(unsigned i = 0, e = InputFileList.size(); i != e; ++i) {
195    // Load the input memory buffer.
196    OwningPtr<MemoryBuffer> InputBuffer;
197    OwningPtr<ObjectImage>  LoadedObject;
198    if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFileList[i],
199                                                     InputBuffer))
200      return Error("unable to read input: '" + ec.message() + "'");
201
202    // Load the object file
203    LoadedObject.reset(Dyld.loadObject(new ObjectBuffer(InputBuffer.take())));
204    if (!LoadedObject) {
205      return Error(Dyld.getErrorString());
206    }
207  }
208
209  // Resolve all the relocations we can.
210  Dyld.resolveRelocations();
211  // Clear instruction cache before code will be executed.
212  MemMgr.invalidateInstructionCache();
213
214  // FIXME: Error out if there are unresolved relocations.
215
216  // Get the address of the entry point (_main by default).
217  void *MainAddress = Dyld.getSymbolAddress(EntryPoint);
218  if (MainAddress == 0)
219    return Error("no definition for '" + EntryPoint + "'");
220
221  // Invalidate the instruction cache for each loaded function.
222  for (unsigned i = 0, e = MemMgr.FunctionMemory.size(); i != e; ++i) {
223    sys::MemoryBlock &Data = MemMgr.FunctionMemory[i];
224    // Make sure the memory is executable.
225    std::string ErrorStr;
226    sys::Memory::InvalidateInstructionCache(Data.base(), Data.size());
227    if (!sys::Memory::setExecutable(Data, &ErrorStr))
228      return Error("unable to mark function executable: '" + ErrorStr + "'");
229  }
230
231  // Dispatch to _main().
232  errs() << "loaded '" << EntryPoint << "' at: " << (void*)MainAddress << "\n";
233
234  int (*Main)(int, const char**) =
235    (int(*)(int,const char**)) uintptr_t(MainAddress);
236  const char **Argv = new const char*[2];
237  // Use the name of the first input object module as argv[0] for the target.
238  Argv[0] = InputFileList[0].c_str();
239  Argv[1] = 0;
240  return Main(1, Argv);
241}
242
243int main(int argc, char **argv) {
244  sys::PrintStackTraceOnErrorSignal();
245  PrettyStackTraceProgram X(argc, argv);
246
247  ProgramName = argv[0];
248  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
249
250  cl::ParseCommandLineOptions(argc, argv, "llvm MC-JIT tool\n");
251
252  switch (Action) {
253  case AC_Execute:
254    return executeInput();
255  case AC_PrintLineInfo:
256    return printLineInfoForInput();
257  }
258}
259