1 //===-- MCJIT.cpp - MC-based Just-in-Time Compiler --------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 #include "llvm/DerivedTypes.h"
12 #include "llvm/Function.h"
13 #include "llvm/ExecutionEngine/GenericValue.h"
14 #include "llvm/ExecutionEngine/MCJIT.h"
15 #include "llvm/ExecutionEngine/JITMemoryManager.h"
16 #include "llvm/MC/MCAsmInfo.h"
17 #include "llvm/Support/ErrorHandling.h"
18 #include "llvm/Support/DynamicLibrary.h"
19 #include "llvm/Support/MemoryBuffer.h"
20 #include "llvm/Target/TargetData.h"
26 static struct RegisterJIT {
27 RegisterJIT() { MCJIT::Register(); }
32 extern "C" void LLVMLinkInMCJIT() {
35 ExecutionEngine *MCJIT::createJIT(Module *M,
36 std::string *ErrorStr,
37 JITMemoryManager *JMM,
38 CodeGenOpt::Level OptLevel,
43 const SmallVectorImpl<std::string>& MAttrs) {
44 // Try to register the program as a source of symbols to resolve against.
46 // FIXME: Don't do this here.
47 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL);
49 // Pick a target either via -march or by guessing the native arch.
51 // FIXME: This should be lifted out of here, it isn't something which should
52 // be part of the JIT policy, rather the burden for this selection should be
54 TargetMachine *TM = MCJIT::selectTarget(M, MArch, MCPU, MAttrs, ErrorStr);
55 if (!TM || (ErrorStr && ErrorStr->length() > 0)) return 0;
56 TM->setCodeModel(CMM);
58 // If the target supports JIT code generation, create the JIT.
59 if (TargetJITInfo *TJ = TM->getJITInfo())
60 return new MCJIT(M, TM, *TJ, JMM, OptLevel, GVsWithCode);
63 *ErrorStr = "target does not support JIT code generation";
67 MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
68 JITMemoryManager *JMM, CodeGenOpt::Level OptLevel,
69 bool AllocateGVsWithCode)
70 : ExecutionEngine(m), TM(tm), M(m), OS(Buffer), Dyld(JMM) {
72 PM.add(new TargetData(*TM->getTargetData()));
74 // Turn the machine code intermediate representation into bytes in memory
75 // that may be executed.
76 if (TM->addPassesToEmitMC(PM, Ctx, OS, CodeGenOpt::Default, false)) {
77 report_fatal_error("Target does not support MC emission!");
81 // FIXME: When we support multiple modules, we'll want to move the code
82 // gen and finalization out of the constructor here and do it more
83 // on-demand as part of getPointerToFunction().
85 // Flush the output buffer so the SmallVector gets its data.
88 // Load the object into the dynamic linker.
89 // FIXME: It would be nice to avoid making yet another copy.
90 MemoryBuffer *MB = MemoryBuffer::getMemBufferCopy(StringRef(Buffer.data(),
92 if (Dyld.loadObject(MB))
93 report_fatal_error(Dyld.getErrorString());
99 void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
100 report_fatal_error("not yet implemented");
104 void *MCJIT::getPointerToFunction(Function *F) {
105 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
106 bool AbortOnFailure = !F->hasExternalWeakLinkage();
107 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
108 addGlobalMapping(F, Addr);
112 Twine Name = TM->getMCAsmInfo()->getGlobalPrefix() + F->getName();
113 return Dyld.getSymbolAddress(Name.str());
116 void *MCJIT::recompileAndRelinkFunction(Function *F) {
117 report_fatal_error("not yet implemented");
120 void MCJIT::freeMachineCodeForFunction(Function *F) {
121 report_fatal_error("not yet implemented");
124 GenericValue MCJIT::runFunction(Function *F,
125 const std::vector<GenericValue> &ArgValues) {
126 assert(F && "Function *F was null at entry to run()");
128 void *FPtr = getPointerToFunction(F);
129 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
130 const FunctionType *FTy = F->getFunctionType();
131 const Type *RetTy = FTy->getReturnType();
133 assert((FTy->getNumParams() == ArgValues.size() ||
134 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
135 "Wrong number of arguments passed into function!");
136 assert(FTy->getNumParams() == ArgValues.size() &&
137 "This doesn't support passing arguments through varargs (yet)!");
139 // Handle some common cases first. These cases correspond to common `main'
141 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
142 switch (ArgValues.size()) {
144 if (FTy->getParamType(0)->isIntegerTy(32) &&
145 FTy->getParamType(1)->isPointerTy() &&
146 FTy->getParamType(2)->isPointerTy()) {
147 int (*PF)(int, char **, const char **) =
148 (int(*)(int, char **, const char **))(intptr_t)FPtr;
150 // Call the function.
152 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
153 (char **)GVTOP(ArgValues[1]),
154 (const char **)GVTOP(ArgValues[2])));
159 if (FTy->getParamType(0)->isIntegerTy(32) &&
160 FTy->getParamType(1)->isPointerTy()) {
161 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
163 // Call the function.
165 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
166 (char **)GVTOP(ArgValues[1])));
171 if (FTy->getNumParams() == 1 &&
172 FTy->getParamType(0)->isIntegerTy(32)) {
174 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
175 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
182 // Handle cases where no arguments are passed first.
183 if (ArgValues.empty()) {
185 switch (RetTy->getTypeID()) {
186 default: llvm_unreachable("Unknown return type for function call!");
187 case Type::IntegerTyID: {
188 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
190 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
191 else if (BitWidth <= 8)
192 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
193 else if (BitWidth <= 16)
194 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
195 else if (BitWidth <= 32)
196 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
197 else if (BitWidth <= 64)
198 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
200 llvm_unreachable("Integer types > 64 bits not supported");
204 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
206 case Type::FloatTyID:
207 rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
209 case Type::DoubleTyID:
210 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
212 case Type::X86_FP80TyID:
213 case Type::FP128TyID:
214 case Type::PPC_FP128TyID:
215 llvm_unreachable("long double not supported yet");
217 case Type::PointerTyID:
218 return PTOGV(((void*(*)())(intptr_t)FPtr)());
222 assert("Full-featured argument passing not supported yet!");
223 return GenericValue();