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