1 //===---- IndirectionUtils.cpp - Utilities for call indirection in Orc ----===//
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 "llvm/ExecutionEngine/Orc/IndirectionUtils.h"
11 #include "llvm/ADT/STLExtras.h"
12 #include "llvm/ADT/Triple.h"
13 #include "llvm/ExecutionEngine/Orc/OrcABISupport.h"
14 #include "llvm/IR/CallSite.h"
15 #include "llvm/IR/IRBuilder.h"
16 #include "llvm/Support/Format.h"
17 #include "llvm/Transforms/Utils/Cloning.h"
18 #include <sstream>
19 
20 using namespace llvm;
21 using namespace llvm::orc;
22 
23 namespace {
24 
25 class CompileCallbackMaterializationUnit : public orc::MaterializationUnit {
26 public:
27   using CompileFunction = JITCompileCallbackManager::CompileFunction;
28 
29   CompileCallbackMaterializationUnit(SymbolStringPtr Name,
30                                      CompileFunction Compile)
31       : MaterializationUnit(SymbolFlagsMap({{Name, JITSymbolFlags::Exported}})),
32         Name(std::move(Name)), Compile(std::move(Compile)) {}
33 
34 private:
35   void materialize(MaterializationResponsibility R) {
36     SymbolMap Result;
37     Result[Name] = JITEvaluatedSymbol(Compile(), JITSymbolFlags::Exported);
38     R.resolve(Result);
39     R.emit();
40   }
41 
42   void discard(const JITDylib &JD, SymbolStringPtr Name) {
43     llvm_unreachable("Discard should never occur on a LMU?");
44   }
45 
46   SymbolStringPtr Name;
47   CompileFunction Compile;
48 };
49 
50 } // namespace
51 
52 namespace llvm {
53 namespace orc {
54 
55 void JITCompileCallbackManager::anchor() {}
56 void IndirectStubsManager::anchor() {}
57 
58 Expected<JITTargetAddress>
59 JITCompileCallbackManager::getCompileCallback(CompileFunction Compile) {
60   if (auto TrampolineAddr = getAvailableTrampolineAddr()) {
61     auto CallbackName = ES.getSymbolStringPool().intern(
62         std::string("cc") + std::to_string(++NextCallbackId));
63 
64     std::lock_guard<std::mutex> Lock(CCMgrMutex);
65     AddrToSymbol[*TrampolineAddr] = CallbackName;
66     cantFail(CallbacksJD.define(
67         llvm::make_unique<CompileCallbackMaterializationUnit>(
68             std::move(CallbackName), std::move(Compile))));
69     return *TrampolineAddr;
70   } else
71     return TrampolineAddr.takeError();
72 }
73 
74 JITTargetAddress JITCompileCallbackManager::executeCompileCallback(
75     JITTargetAddress TrampolineAddr) {
76   SymbolStringPtr Name;
77 
78   {
79     std::unique_lock<std::mutex> Lock(CCMgrMutex);
80     auto I = AddrToSymbol.find(TrampolineAddr);
81 
82     // If this address is not associated with a compile callback then report an
83     // error to the execution session and return ErrorHandlerAddress to the
84     // callee.
85     if (I == AddrToSymbol.end()) {
86       Lock.unlock();
87       std::string ErrMsg;
88       {
89         raw_string_ostream ErrMsgStream(ErrMsg);
90         ErrMsgStream << "No compile callback for trampoline at "
91                      << format("0x%016x", TrampolineAddr);
92       }
93       ES.reportError(
94           make_error<StringError>(std::move(ErrMsg), inconvertibleErrorCode()));
95       return ErrorHandlerAddress;
96     } else
97       Name = I->second;
98   }
99 
100   if (auto Sym = lookup({&CallbacksJD}, Name))
101     return Sym->getAddress();
102   else {
103     // If anything goes wrong materializing Sym then report it to the session
104     // and return the ErrorHandlerAddress;
105     ES.reportError(Sym.takeError());
106     return ErrorHandlerAddress;
107   }
108 }
109 
110 std::unique_ptr<JITCompileCallbackManager>
111 createLocalCompileCallbackManager(const Triple &T, ExecutionSession &ES,
112                                   JITTargetAddress ErrorHandlerAddress) {
113   switch (T.getArch()) {
114     default: return nullptr;
115 
116     case Triple::aarch64: {
117       typedef orc::LocalJITCompileCallbackManager<orc::OrcAArch64> CCMgrT;
118       return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
119     }
120 
121     case Triple::x86: {
122       typedef orc::LocalJITCompileCallbackManager<orc::OrcI386> CCMgrT;
123       return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
124     }
125 
126     case Triple::mips: {
127       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Be> CCMgrT;
128       return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
129     }
130     case Triple::mipsel: {
131       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Le> CCMgrT;
132       return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
133     }
134 
135     case Triple::mips64:
136     case Triple::mips64el: {
137       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips64> CCMgrT;
138       return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
139     }
140 
141     case Triple::x86_64: {
142       if ( T.getOS() == Triple::OSType::Win32 ) {
143         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT;
144         return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
145       } else {
146         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT;
147         return llvm::make_unique<CCMgrT>(ES, ErrorHandlerAddress);
148       }
149     }
150 
151   }
152 }
153 
154 std::function<std::unique_ptr<IndirectStubsManager>()>
155 createLocalIndirectStubsManagerBuilder(const Triple &T) {
156   switch (T.getArch()) {
157     default:
158       return [](){
159         return llvm::make_unique<
160                        orc::LocalIndirectStubsManager<orc::OrcGenericABI>>();
161       };
162 
163     case Triple::aarch64:
164       return [](){
165         return llvm::make_unique<
166                        orc::LocalIndirectStubsManager<orc::OrcAArch64>>();
167       };
168 
169     case Triple::x86:
170       return [](){
171         return llvm::make_unique<
172                        orc::LocalIndirectStubsManager<orc::OrcI386>>();
173       };
174 
175     case Triple::mips:
176       return [](){
177           return llvm::make_unique<
178                       orc::LocalIndirectStubsManager<orc::OrcMips32Be>>();
179       };
180 
181     case Triple::mipsel:
182       return [](){
183           return llvm::make_unique<
184                       orc::LocalIndirectStubsManager<orc::OrcMips32Le>>();
185       };
186 
187     case Triple::mips64:
188     case Triple::mips64el:
189       return [](){
190           return llvm::make_unique<
191                       orc::LocalIndirectStubsManager<orc::OrcMips64>>();
192       };
193 
194     case Triple::x86_64:
195       if (T.getOS() == Triple::OSType::Win32) {
196         return [](){
197           return llvm::make_unique<
198                      orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>();
199         };
200       } else {
201         return [](){
202           return llvm::make_unique<
203                      orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>();
204         };
205       }
206 
207   }
208 }
209 
210 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) {
211   Constant *AddrIntVal =
212     ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr);
213   Constant *AddrPtrVal =
214     ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal,
215                           PointerType::get(&FT, 0));
216   return AddrPtrVal;
217 }
218 
219 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
220                                   const Twine &Name, Constant *Initializer) {
221   auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage,
222                                Initializer, Name, nullptr,
223                                GlobalValue::NotThreadLocal, 0, true);
224   IP->setVisibility(GlobalValue::HiddenVisibility);
225   return IP;
226 }
227 
228 void makeStub(Function &F, Value &ImplPointer) {
229   assert(F.isDeclaration() && "Can't turn a definition into a stub.");
230   assert(F.getParent() && "Function isn't in a module.");
231   Module &M = *F.getParent();
232   BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F);
233   IRBuilder<> Builder(EntryBlock);
234   LoadInst *ImplAddr = Builder.CreateLoad(&ImplPointer);
235   std::vector<Value*> CallArgs;
236   for (auto &A : F.args())
237     CallArgs.push_back(&A);
238   CallInst *Call = Builder.CreateCall(ImplAddr, CallArgs);
239   Call->setTailCall();
240   Call->setAttributes(F.getAttributes());
241   if (F.getReturnType()->isVoidTy())
242     Builder.CreateRetVoid();
243   else
244     Builder.CreateRet(Call);
245 }
246 
247 // Utility class for renaming global values and functions during partitioning.
248 class GlobalRenamer {
249 public:
250 
251   static bool needsRenaming(const Value &New) {
252     return !New.hasName() || New.getName().startswith("\01L");
253   }
254 
255   const std::string& getRename(const Value &Orig) {
256     // See if we have a name for this global.
257     {
258       auto I = Names.find(&Orig);
259       if (I != Names.end())
260         return I->second;
261     }
262 
263     // Nope. Create a new one.
264     // FIXME: Use a more robust uniquing scheme. (This may blow up if the user
265     //        writes a "__orc_anon[[:digit:]]* method).
266     unsigned ID = Names.size();
267     std::ostringstream NameStream;
268     NameStream << "__orc_anon" << ID++;
269     auto I = Names.insert(std::make_pair(&Orig, NameStream.str()));
270     return I.first->second;
271   }
272 private:
273   DenseMap<const Value*, std::string> Names;
274 };
275 
276 static void raiseVisibilityOnValue(GlobalValue &V, GlobalRenamer &R) {
277   if (V.hasLocalLinkage()) {
278     if (R.needsRenaming(V))
279       V.setName(R.getRename(V));
280     V.setLinkage(GlobalValue::ExternalLinkage);
281     V.setVisibility(GlobalValue::HiddenVisibility);
282   }
283   V.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
284   assert(!R.needsRenaming(V) && "Invalid global name.");
285 }
286 
287 void makeAllSymbolsExternallyAccessible(Module &M) {
288   GlobalRenamer Renamer;
289 
290   for (auto &F : M)
291     raiseVisibilityOnValue(F, Renamer);
292 
293   for (auto &GV : M.globals())
294     raiseVisibilityOnValue(GV, Renamer);
295 
296   for (auto &A : M.aliases())
297     raiseVisibilityOnValue(A, Renamer);
298 }
299 
300 Function* cloneFunctionDecl(Module &Dst, const Function &F,
301                             ValueToValueMapTy *VMap) {
302   Function *NewF =
303     Function::Create(cast<FunctionType>(F.getValueType()),
304                      F.getLinkage(), F.getName(), &Dst);
305   NewF->copyAttributesFrom(&F);
306 
307   if (VMap) {
308     (*VMap)[&F] = NewF;
309     auto NewArgI = NewF->arg_begin();
310     for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE;
311          ++ArgI, ++NewArgI)
312       (*VMap)[&*ArgI] = &*NewArgI;
313   }
314 
315   return NewF;
316 }
317 
318 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
319                       ValueMaterializer *Materializer,
320                       Function *NewF) {
321   assert(!OrigF.isDeclaration() && "Nothing to move");
322   if (!NewF)
323     NewF = cast<Function>(VMap[&OrigF]);
324   else
325     assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap.");
326   assert(NewF && "Function mapping missing from VMap.");
327   assert(NewF->getParent() != OrigF.getParent() &&
328          "moveFunctionBody should only be used to move bodies between "
329          "modules.");
330 
331   SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned.
332   CloneFunctionInto(NewF, &OrigF, VMap, /*ModuleLevelChanges=*/true, Returns,
333                     "", nullptr, nullptr, Materializer);
334   OrigF.deleteBody();
335 }
336 
337 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
338                                         ValueToValueMapTy *VMap) {
339   GlobalVariable *NewGV = new GlobalVariable(
340       Dst, GV.getValueType(), GV.isConstant(),
341       GV.getLinkage(), nullptr, GV.getName(), nullptr,
342       GV.getThreadLocalMode(), GV.getType()->getAddressSpace());
343   NewGV->copyAttributesFrom(&GV);
344   if (VMap)
345     (*VMap)[&GV] = NewGV;
346   return NewGV;
347 }
348 
349 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
350                                    ValueToValueMapTy &VMap,
351                                    ValueMaterializer *Materializer,
352                                    GlobalVariable *NewGV) {
353   assert(OrigGV.hasInitializer() && "Nothing to move");
354   if (!NewGV)
355     NewGV = cast<GlobalVariable>(VMap[&OrigGV]);
356   else
357     assert(VMap[&OrigGV] == NewGV &&
358            "Incorrect global variable mapping in VMap.");
359   assert(NewGV->getParent() != OrigGV.getParent() &&
360          "moveGlobalVariableInitializer should only be used to move "
361          "initializers between modules");
362 
363   NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None,
364                                  nullptr, Materializer));
365 }
366 
367 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
368                                   ValueToValueMapTy &VMap) {
369   assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?");
370   auto *NewA = GlobalAlias::create(OrigA.getValueType(),
371                                    OrigA.getType()->getPointerAddressSpace(),
372                                    OrigA.getLinkage(), OrigA.getName(), &Dst);
373   NewA->copyAttributesFrom(&OrigA);
374   VMap[&OrigA] = NewA;
375   return NewA;
376 }
377 
378 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src,
379                               ValueToValueMapTy &VMap) {
380   auto *MFs = Src.getModuleFlagsMetadata();
381   if (!MFs)
382     return;
383   for (auto *MF : MFs->operands())
384     Dst.addModuleFlag(MapMetadata(MF, VMap));
385 }
386 
387 } // End namespace orc.
388 } // End namespace llvm.
389