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 = lookup({&CallbacksJD}, Name))
103     return Sym->getAddress();
104   else {
105     // If anything goes wrong materializing Sym then report it to the session
106     // and return the ErrorHandlerAddress;
107     ES.reportError(Sym.takeError());
108     return ErrorHandlerAddress;
109   }
110 }
111 
112 Expected<std::unique_ptr<JITCompileCallbackManager>>
113 createLocalCompileCallbackManager(const Triple &T, ExecutionSession &ES,
114                                   JITTargetAddress ErrorHandlerAddress) {
115   switch (T.getArch()) {
116   default:
117     return make_error<StringError>(
118         std::string("No callback manager available for ") + T.str(),
119         inconvertibleErrorCode());
120   case Triple::aarch64: {
121     typedef orc::LocalJITCompileCallbackManager<orc::OrcAArch64> CCMgrT;
122     return CCMgrT::Create(ES, ErrorHandlerAddress);
123     }
124 
125     case Triple::x86: {
126       typedef orc::LocalJITCompileCallbackManager<orc::OrcI386> CCMgrT;
127       return CCMgrT::Create(ES, ErrorHandlerAddress);
128     }
129 
130     case Triple::mips: {
131       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Be> CCMgrT;
132       return CCMgrT::Create(ES, ErrorHandlerAddress);
133     }
134     case Triple::mipsel: {
135       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Le> CCMgrT;
136       return CCMgrT::Create(ES, ErrorHandlerAddress);
137     }
138 
139     case Triple::mips64:
140     case Triple::mips64el: {
141       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips64> CCMgrT;
142       return CCMgrT::Create(ES, ErrorHandlerAddress);
143     }
144 
145     case Triple::x86_64: {
146       if ( T.getOS() == Triple::OSType::Win32 ) {
147         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT;
148         return CCMgrT::Create(ES, ErrorHandlerAddress);
149       } else {
150         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT;
151         return CCMgrT::Create(ES, ErrorHandlerAddress);
152       }
153     }
154 
155   }
156 }
157 
158 std::function<std::unique_ptr<IndirectStubsManager>()>
159 createLocalIndirectStubsManagerBuilder(const Triple &T) {
160   switch (T.getArch()) {
161     default:
162       return [](){
163         return llvm::make_unique<
164                        orc::LocalIndirectStubsManager<orc::OrcGenericABI>>();
165       };
166 
167     case Triple::aarch64:
168       return [](){
169         return llvm::make_unique<
170                        orc::LocalIndirectStubsManager<orc::OrcAArch64>>();
171       };
172 
173     case Triple::x86:
174       return [](){
175         return llvm::make_unique<
176                        orc::LocalIndirectStubsManager<orc::OrcI386>>();
177       };
178 
179     case Triple::mips:
180       return [](){
181           return llvm::make_unique<
182                       orc::LocalIndirectStubsManager<orc::OrcMips32Be>>();
183       };
184 
185     case Triple::mipsel:
186       return [](){
187           return llvm::make_unique<
188                       orc::LocalIndirectStubsManager<orc::OrcMips32Le>>();
189       };
190 
191     case Triple::mips64:
192     case Triple::mips64el:
193       return [](){
194           return llvm::make_unique<
195                       orc::LocalIndirectStubsManager<orc::OrcMips64>>();
196       };
197 
198     case Triple::x86_64:
199       if (T.getOS() == Triple::OSType::Win32) {
200         return [](){
201           return llvm::make_unique<
202                      orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>();
203         };
204       } else {
205         return [](){
206           return llvm::make_unique<
207                      orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>();
208         };
209       }
210 
211   }
212 }
213 
214 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) {
215   Constant *AddrIntVal =
216     ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr);
217   Constant *AddrPtrVal =
218     ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal,
219                           PointerType::get(&FT, 0));
220   return AddrPtrVal;
221 }
222 
223 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
224                                   const Twine &Name, Constant *Initializer) {
225   auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage,
226                                Initializer, Name, nullptr,
227                                GlobalValue::NotThreadLocal, 0, true);
228   IP->setVisibility(GlobalValue::HiddenVisibility);
229   return IP;
230 }
231 
232 void makeStub(Function &F, Value &ImplPointer) {
233   assert(F.isDeclaration() && "Can't turn a definition into a stub.");
234   assert(F.getParent() && "Function isn't in a module.");
235   Module &M = *F.getParent();
236   BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F);
237   IRBuilder<> Builder(EntryBlock);
238   LoadInst *ImplAddr = Builder.CreateLoad(&ImplPointer);
239   std::vector<Value*> CallArgs;
240   for (auto &A : F.args())
241     CallArgs.push_back(&A);
242   CallInst *Call = Builder.CreateCall(ImplAddr, CallArgs);
243   Call->setTailCall();
244   Call->setAttributes(F.getAttributes());
245   if (F.getReturnType()->isVoidTy())
246     Builder.CreateRetVoid();
247   else
248     Builder.CreateRet(Call);
249 }
250 
251 std::vector<GlobalValue *> SymbolLinkagePromoter::operator()(Module &M) {
252   std::vector<GlobalValue *> PromotedGlobals;
253 
254   for (auto &GV : M.global_values()) {
255     bool Promoted = true;
256 
257     // Rename if necessary.
258     if (!GV.hasName())
259       GV.setName("__orc_anon." + Twine(NextId++));
260     else if (GV.getName().startswith("\01L"))
261       GV.setName("__" + GV.getName().substr(1) + "." + Twine(NextId++));
262     else if (GV.hasLocalLinkage())
263       GV.setName("__orc_lcl." + GV.getName() + "." + Twine(NextId++));
264     else
265       Promoted = false;
266 
267     if (GV.hasLocalLinkage()) {
268       GV.setLinkage(GlobalValue::ExternalLinkage);
269       GV.setVisibility(GlobalValue::HiddenVisibility);
270       Promoted = true;
271     }
272     GV.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
273 
274     if (Promoted)
275       PromotedGlobals.push_back(&GV);
276   }
277 
278   return PromotedGlobals;
279 }
280 
281 Function* cloneFunctionDecl(Module &Dst, const Function &F,
282                             ValueToValueMapTy *VMap) {
283   Function *NewF =
284     Function::Create(cast<FunctionType>(F.getValueType()),
285                      F.getLinkage(), F.getName(), &Dst);
286   NewF->copyAttributesFrom(&F);
287 
288   if (VMap) {
289     (*VMap)[&F] = NewF;
290     auto NewArgI = NewF->arg_begin();
291     for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE;
292          ++ArgI, ++NewArgI)
293       (*VMap)[&*ArgI] = &*NewArgI;
294   }
295 
296   return NewF;
297 }
298 
299 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
300                       ValueMaterializer *Materializer,
301                       Function *NewF) {
302   assert(!OrigF.isDeclaration() && "Nothing to move");
303   if (!NewF)
304     NewF = cast<Function>(VMap[&OrigF]);
305   else
306     assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap.");
307   assert(NewF && "Function mapping missing from VMap.");
308   assert(NewF->getParent() != OrigF.getParent() &&
309          "moveFunctionBody should only be used to move bodies between "
310          "modules.");
311 
312   SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned.
313   CloneFunctionInto(NewF, &OrigF, VMap, /*ModuleLevelChanges=*/true, Returns,
314                     "", nullptr, nullptr, Materializer);
315   OrigF.deleteBody();
316 }
317 
318 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
319                                         ValueToValueMapTy *VMap) {
320   GlobalVariable *NewGV = new GlobalVariable(
321       Dst, GV.getValueType(), GV.isConstant(),
322       GV.getLinkage(), nullptr, GV.getName(), nullptr,
323       GV.getThreadLocalMode(), GV.getType()->getAddressSpace());
324   NewGV->copyAttributesFrom(&GV);
325   if (VMap)
326     (*VMap)[&GV] = NewGV;
327   return NewGV;
328 }
329 
330 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
331                                    ValueToValueMapTy &VMap,
332                                    ValueMaterializer *Materializer,
333                                    GlobalVariable *NewGV) {
334   assert(OrigGV.hasInitializer() && "Nothing to move");
335   if (!NewGV)
336     NewGV = cast<GlobalVariable>(VMap[&OrigGV]);
337   else
338     assert(VMap[&OrigGV] == NewGV &&
339            "Incorrect global variable mapping in VMap.");
340   assert(NewGV->getParent() != OrigGV.getParent() &&
341          "moveGlobalVariableInitializer should only be used to move "
342          "initializers between modules");
343 
344   NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None,
345                                  nullptr, Materializer));
346 }
347 
348 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
349                                   ValueToValueMapTy &VMap) {
350   assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?");
351   auto *NewA = GlobalAlias::create(OrigA.getValueType(),
352                                    OrigA.getType()->getPointerAddressSpace(),
353                                    OrigA.getLinkage(), OrigA.getName(), &Dst);
354   NewA->copyAttributesFrom(&OrigA);
355   VMap[&OrigA] = NewA;
356   return NewA;
357 }
358 
359 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src,
360                               ValueToValueMapTy &VMap) {
361   auto *MFs = Src.getModuleFlagsMetadata();
362   if (!MFs)
363     return;
364   for (auto *MF : MFs->operands())
365     Dst.addModuleFlag(MapMetadata(MF, VMap));
366 }
367 
368 } // End namespace orc.
369 } // End namespace llvm.
370