1 //===-- MCJIT.cpp - MC-based Just-in-Time Compiler ------------------------===//
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 #include "MCJIT.h"
11 #include "MCJITMemoryManager.h"
12 #include "llvm/DerivedTypes.h"
13 #include "llvm/Function.h"
14 #include "llvm/ExecutionEngine/GenericValue.h"
15 #include "llvm/ExecutionEngine/MCJIT.h"
16 #include "llvm/ExecutionEngine/JITMemoryManager.h"
17 #include "llvm/MC/MCAsmInfo.h"
18 #include "llvm/Support/ErrorHandling.h"
19 #include "llvm/Support/DynamicLibrary.h"
20 #include "llvm/Support/MemoryBuffer.h"
21 #include "llvm/Target/TargetData.h"
22
23 using namespace llvm;
24
25 namespace {
26
27 static struct RegisterJIT {
RegisterJIT__anon839346cc0111::RegisterJIT28 RegisterJIT() { MCJIT::Register(); }
29 } JITRegistrator;
30
31 }
32
LLVMLinkInMCJIT()33 extern "C" void LLVMLinkInMCJIT() {
34 }
35
createJIT(Module * M,std::string * ErrorStr,JITMemoryManager * JMM,bool GVsWithCode,TargetMachine * TM)36 ExecutionEngine *MCJIT::createJIT(Module *M,
37 std::string *ErrorStr,
38 JITMemoryManager *JMM,
39 bool GVsWithCode,
40 TargetMachine *TM) {
41 // Try to register the program as a source of symbols to resolve against.
42 //
43 // FIXME: Don't do this here.
44 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL);
45
46 // If the target supports JIT code generation, create the JIT.
47 if (TargetJITInfo *TJ = TM->getJITInfo())
48 return new MCJIT(M, TM, *TJ, new MCJITMemoryManager(JMM, M), GVsWithCode);
49
50 if (ErrorStr)
51 *ErrorStr = "target does not support JIT code generation";
52 return 0;
53 }
54
MCJIT(Module * m,TargetMachine * tm,TargetJITInfo & tji,RTDyldMemoryManager * MM,bool AllocateGVsWithCode)55 MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
56 RTDyldMemoryManager *MM, bool AllocateGVsWithCode)
57 : ExecutionEngine(m), TM(tm), MemMgr(MM), M(m), OS(Buffer), Dyld(MM) {
58
59 setTargetData(TM->getTargetData());
60 PM.add(new TargetData(*TM->getTargetData()));
61
62 // Turn the machine code intermediate representation into bytes in memory
63 // that may be executed.
64 if (TM->addPassesToEmitMC(PM, Ctx, OS, false)) {
65 report_fatal_error("Target does not support MC emission!");
66 }
67
68 // Initialize passes.
69 // FIXME: When we support multiple modules, we'll want to move the code
70 // gen and finalization out of the constructor here and do it more
71 // on-demand as part of getPointerToFunction().
72 PM.run(*M);
73 // Flush the output buffer so the SmallVector gets its data.
74 OS.flush();
75
76 // Load the object into the dynamic linker.
77 MemoryBuffer *MB = MemoryBuffer::getMemBuffer(StringRef(Buffer.data(),
78 Buffer.size()),
79 "", false);
80 if (Dyld.loadObject(MB))
81 report_fatal_error(Dyld.getErrorString());
82 // Resolve any relocations.
83 Dyld.resolveRelocations();
84 }
85
~MCJIT()86 MCJIT::~MCJIT() {
87 delete MemMgr;
88 delete TM;
89 }
90
getPointerToBasicBlock(BasicBlock * BB)91 void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
92 report_fatal_error("not yet implemented");
93 }
94
getPointerToFunction(Function * F)95 void *MCJIT::getPointerToFunction(Function *F) {
96 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
97 bool AbortOnFailure = !F->hasExternalWeakLinkage();
98 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
99 addGlobalMapping(F, Addr);
100 return Addr;
101 }
102
103 // FIXME: Should we be using the mangler for this? Probably.
104 StringRef BaseName = F->getName();
105 if (BaseName[0] == '\1')
106 return (void*)Dyld.getSymbolAddress(BaseName.substr(1));
107 return (void*)Dyld.getSymbolAddress((TM->getMCAsmInfo()->getGlobalPrefix()
108 + BaseName).str());
109 }
110
recompileAndRelinkFunction(Function * F)111 void *MCJIT::recompileAndRelinkFunction(Function *F) {
112 report_fatal_error("not yet implemented");
113 }
114
freeMachineCodeForFunction(Function * F)115 void MCJIT::freeMachineCodeForFunction(Function *F) {
116 report_fatal_error("not yet implemented");
117 }
118
runFunction(Function * F,const std::vector<GenericValue> & ArgValues)119 GenericValue MCJIT::runFunction(Function *F,
120 const std::vector<GenericValue> &ArgValues) {
121 assert(F && "Function *F was null at entry to run()");
122
123 void *FPtr = getPointerToFunction(F);
124 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
125 FunctionType *FTy = F->getFunctionType();
126 Type *RetTy = FTy->getReturnType();
127
128 assert((FTy->getNumParams() == ArgValues.size() ||
129 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
130 "Wrong number of arguments passed into function!");
131 assert(FTy->getNumParams() == ArgValues.size() &&
132 "This doesn't support passing arguments through varargs (yet)!");
133
134 // Handle some common cases first. These cases correspond to common `main'
135 // prototypes.
136 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
137 switch (ArgValues.size()) {
138 case 3:
139 if (FTy->getParamType(0)->isIntegerTy(32) &&
140 FTy->getParamType(1)->isPointerTy() &&
141 FTy->getParamType(2)->isPointerTy()) {
142 int (*PF)(int, char **, const char **) =
143 (int(*)(int, char **, const char **))(intptr_t)FPtr;
144
145 // Call the function.
146 GenericValue rv;
147 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
148 (char **)GVTOP(ArgValues[1]),
149 (const char **)GVTOP(ArgValues[2])));
150 return rv;
151 }
152 break;
153 case 2:
154 if (FTy->getParamType(0)->isIntegerTy(32) &&
155 FTy->getParamType(1)->isPointerTy()) {
156 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
157
158 // Call the function.
159 GenericValue rv;
160 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
161 (char **)GVTOP(ArgValues[1])));
162 return rv;
163 }
164 break;
165 case 1:
166 if (FTy->getNumParams() == 1 &&
167 FTy->getParamType(0)->isIntegerTy(32)) {
168 GenericValue rv;
169 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
170 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
171 return rv;
172 }
173 break;
174 }
175 }
176
177 // Handle cases where no arguments are passed first.
178 if (ArgValues.empty()) {
179 GenericValue rv;
180 switch (RetTy->getTypeID()) {
181 default: llvm_unreachable("Unknown return type for function call!");
182 case Type::IntegerTyID: {
183 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
184 if (BitWidth == 1)
185 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
186 else if (BitWidth <= 8)
187 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
188 else if (BitWidth <= 16)
189 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
190 else if (BitWidth <= 32)
191 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
192 else if (BitWidth <= 64)
193 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
194 else
195 llvm_unreachable("Integer types > 64 bits not supported");
196 return rv;
197 }
198 case Type::VoidTyID:
199 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
200 return rv;
201 case Type::FloatTyID:
202 rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
203 return rv;
204 case Type::DoubleTyID:
205 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
206 return rv;
207 case Type::X86_FP80TyID:
208 case Type::FP128TyID:
209 case Type::PPC_FP128TyID:
210 llvm_unreachable("long double not supported yet");
211 case Type::PointerTyID:
212 return PTOGV(((void*(*)())(intptr_t)FPtr)());
213 }
214 }
215
216 llvm_unreachable("Full-featured argument passing not supported yet!");
217 }
218
getPointerToNamedFunction(const std::string & Name,bool AbortOnFailure)219 void *MCJIT::getPointerToNamedFunction(const std::string &Name,
220 bool AbortOnFailure){
221 if (!isSymbolSearchingDisabled() && MemMgr) {
222 void *ptr = MemMgr->getPointerToNamedFunction(Name, false);
223 if (ptr)
224 return ptr;
225 }
226
227 /// If a LazyFunctionCreator is installed, use it to get/create the function.
228 if (LazyFunctionCreator)
229 if (void *RP = LazyFunctionCreator(Name))
230 return RP;
231
232 if (AbortOnFailure) {
233 report_fatal_error("Program used external function '"+Name+
234 "' which could not be resolved!");
235 }
236 return 0;
237 }
238