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/StringMap.h"
15 #include "llvm/ADT/OwningPtr.h"
16 #include "llvm/ExecutionEngine/RuntimeDyld.h"
17 #include "llvm/Object/MachOObject.h"
18 #include "llvm/Support/CommandLine.h"
19 #include "llvm/Support/ManagedStatic.h"
20 #include "llvm/Support/Memory.h"
21 #include "llvm/Support/MemoryBuffer.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include "llvm/Support/system_error.h"
24 using namespace llvm;
25 using namespace llvm::object;
26
27 static cl::list<std::string>
28 InputFileList(cl::Positional, cl::ZeroOrMore,
29 cl::desc("<input file>"));
30
31 enum ActionType {
32 AC_Execute
33 };
34
35 static cl::opt<ActionType>
36 Action(cl::desc("Action to perform:"),
37 cl::init(AC_Execute),
38 cl::values(clEnumValN(AC_Execute, "execute",
39 "Load, link, and execute the inputs."),
40 clEnumValEnd));
41
42 static cl::opt<std::string>
43 EntryPoint("entry",
44 cl::desc("Function to call as entry point."),
45 cl::init("_main"));
46
47 /* *** */
48
49 // A trivial memory manager that doesn't do anything fancy, just uses the
50 // support library allocation routines directly.
51 class TrivialMemoryManager : public RTDyldMemoryManager {
52 public:
53 SmallVector<sys::MemoryBlock, 16> FunctionMemory;
54 SmallVector<sys::MemoryBlock, 16> DataMemory;
55
56 uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
57 unsigned SectionID);
58 uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
59 unsigned SectionID);
60
getPointerToNamedFunction(const std::string & Name,bool AbortOnFailure=true)61 virtual void *getPointerToNamedFunction(const std::string &Name,
62 bool AbortOnFailure = true) {
63 return 0;
64 }
65
66 };
67
allocateCodeSection(uintptr_t Size,unsigned Alignment,unsigned SectionID)68 uint8_t *TrivialMemoryManager::allocateCodeSection(uintptr_t Size,
69 unsigned Alignment,
70 unsigned SectionID) {
71 return (uint8_t*)sys::Memory::AllocateRWX(Size, 0, 0).base();
72 }
73
allocateDataSection(uintptr_t Size,unsigned Alignment,unsigned SectionID)74 uint8_t *TrivialMemoryManager::allocateDataSection(uintptr_t Size,
75 unsigned Alignment,
76 unsigned SectionID) {
77 return (uint8_t*)sys::Memory::AllocateRWX(Size, 0, 0).base();
78 }
79
80 static const char *ProgramName;
81
Message(const char * Type,const Twine & Msg)82 static void Message(const char *Type, const Twine &Msg) {
83 errs() << ProgramName << ": " << Type << ": " << Msg << "\n";
84 }
85
Error(const Twine & Msg)86 static int Error(const Twine &Msg) {
87 Message("error", Msg);
88 return 1;
89 }
90
91 /* *** */
92
executeInput()93 static int executeInput() {
94 // Instantiate a dynamic linker.
95 TrivialMemoryManager *MemMgr = new TrivialMemoryManager;
96 RuntimeDyld Dyld(MemMgr);
97
98 // If we don't have any input files, read from stdin.
99 if (!InputFileList.size())
100 InputFileList.push_back("-");
101 for(unsigned i = 0, e = InputFileList.size(); i != e; ++i) {
102 // Load the input memory buffer.
103 OwningPtr<MemoryBuffer> InputBuffer;
104 if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFileList[i],
105 InputBuffer))
106 return Error("unable to read input: '" + ec.message() + "'");
107
108 // Load the object file into it.
109 if (Dyld.loadObject(InputBuffer.take())) {
110 return Error(Dyld.getErrorString());
111 }
112 }
113
114 // Resolve all the relocations we can.
115 Dyld.resolveRelocations();
116
117 // FIXME: Error out if there are unresolved relocations.
118
119 // Get the address of the entry point (_main by default).
120 void *MainAddress = Dyld.getSymbolAddress(EntryPoint);
121 if (MainAddress == 0)
122 return Error("no definition for '" + EntryPoint + "'");
123
124 // Invalidate the instruction cache for each loaded function.
125 for (unsigned i = 0, e = MemMgr->FunctionMemory.size(); i != e; ++i) {
126 sys::MemoryBlock &Data = MemMgr->FunctionMemory[i];
127 // Make sure the memory is executable.
128 std::string ErrorStr;
129 sys::Memory::InvalidateInstructionCache(Data.base(), Data.size());
130 if (!sys::Memory::setExecutable(Data, &ErrorStr))
131 return Error("unable to mark function executable: '" + ErrorStr + "'");
132 }
133
134 // Dispatch to _main().
135 errs() << "loaded '" << EntryPoint << "' at: " << (void*)MainAddress << "\n";
136
137 int (*Main)(int, const char**) =
138 (int(*)(int,const char**)) uintptr_t(MainAddress);
139 const char **Argv = new const char*[2];
140 // Use the name of the first input object module as argv[0] for the target.
141 Argv[0] = InputFileList[0].c_str();
142 Argv[1] = 0;
143 return Main(1, Argv);
144 }
145
main(int argc,char ** argv)146 int main(int argc, char **argv) {
147 ProgramName = argv[0];
148 llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
149
150 cl::ParseCommandLineOptions(argc, argv, "llvm MC-JIT tool\n");
151
152 switch (Action) {
153 case AC_Execute:
154 return executeInput();
155 }
156 }
157