1 //===---- IndirectionUtils.cpp - Utilities for call indirection in Orc ----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/ExecutionEngine/Orc/IndirectionUtils.h"
10 #include "llvm/ADT/STLExtras.h"
11 #include "llvm/ADT/Triple.h"
12 #include "llvm/ExecutionEngine/Orc/OrcABISupport.h"
13 #include "llvm/IR/IRBuilder.h"
14 #include "llvm/Support/Format.h"
15 #include "llvm/Transforms/Utils/Cloning.h"
16 #include <sstream>
17 
18 using namespace llvm;
19 using namespace llvm::orc;
20 
21 namespace {
22 
23 class CompileCallbackMaterializationUnit : public orc::MaterializationUnit {
24 public:
25   using CompileFunction = JITCompileCallbackManager::CompileFunction;
26 
27   CompileCallbackMaterializationUnit(SymbolStringPtr Name,
28                                      CompileFunction Compile)
29       : MaterializationUnit(SymbolFlagsMap({{Name, JITSymbolFlags::Exported}}),
30                             nullptr),
31         Name(std::move(Name)), Compile(std::move(Compile)) {}
32 
33   StringRef getName() const override { return "<Compile Callbacks>"; }
34 
35 private:
36   void materialize(std::unique_ptr<MaterializationResponsibility> R) override {
37     SymbolMap Result;
38     Result[Name] = JITEvaluatedSymbol(Compile(), JITSymbolFlags::Exported);
39     // No dependencies, so these calls cannot fail.
40     cantFail(R->notifyResolved(Result));
41     cantFail(R->notifyEmitted());
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 TrampolinePool::~TrampolinePool() {}
58 void IndirectStubsManager::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(
69         CallbacksJD.define(std::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%016" PRIx64, 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 =
103           ES.lookup(makeJITDylibSearchOrder(
104                         &CallbacksJD, JITDylibLookupFlags::MatchAllSymbols),
105                     Name))
106     return Sym->getAddress();
107   else {
108     llvm::dbgs() << "Didn't find callback.\n";
109     // If anything goes wrong materializing Sym then report it to the session
110     // and return the ErrorHandlerAddress;
111     ES.reportError(Sym.takeError());
112     return ErrorHandlerAddress;
113   }
114 }
115 
116 Expected<std::unique_ptr<JITCompileCallbackManager>>
117 createLocalCompileCallbackManager(const Triple &T, ExecutionSession &ES,
118                                   JITTargetAddress ErrorHandlerAddress) {
119   switch (T.getArch()) {
120   default:
121     return make_error<StringError>(
122         std::string("No callback manager available for ") + T.str(),
123         inconvertibleErrorCode());
124   case Triple::aarch64:
125   case Triple::aarch64_32: {
126     typedef orc::LocalJITCompileCallbackManager<orc::OrcAArch64> CCMgrT;
127     return CCMgrT::Create(ES, ErrorHandlerAddress);
128     }
129 
130     case Triple::x86: {
131       typedef orc::LocalJITCompileCallbackManager<orc::OrcI386> CCMgrT;
132       return CCMgrT::Create(ES, ErrorHandlerAddress);
133     }
134 
135     case Triple::mips: {
136       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Be> CCMgrT;
137       return CCMgrT::Create(ES, ErrorHandlerAddress);
138     }
139     case Triple::mipsel: {
140       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Le> CCMgrT;
141       return CCMgrT::Create(ES, ErrorHandlerAddress);
142     }
143 
144     case Triple::mips64:
145     case Triple::mips64el: {
146       typedef orc::LocalJITCompileCallbackManager<orc::OrcMips64> CCMgrT;
147       return CCMgrT::Create(ES, ErrorHandlerAddress);
148     }
149 
150     case Triple::x86_64: {
151       if (T.getOS() == Triple::OSType::Win32) {
152         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT;
153         return CCMgrT::Create(ES, ErrorHandlerAddress);
154       } else {
155         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT;
156         return CCMgrT::Create(ES, ErrorHandlerAddress);
157       }
158     }
159 
160   }
161 }
162 
163 std::function<std::unique_ptr<IndirectStubsManager>()>
164 createLocalIndirectStubsManagerBuilder(const Triple &T) {
165   switch (T.getArch()) {
166     default:
167       return [](){
168         return std::make_unique<
169                        orc::LocalIndirectStubsManager<orc::OrcGenericABI>>();
170       };
171 
172     case Triple::aarch64:
173     case Triple::aarch64_32:
174       return [](){
175         return std::make_unique<
176                        orc::LocalIndirectStubsManager<orc::OrcAArch64>>();
177       };
178 
179     case Triple::x86:
180       return [](){
181         return std::make_unique<
182                        orc::LocalIndirectStubsManager<orc::OrcI386>>();
183       };
184 
185     case Triple::mips:
186       return [](){
187           return std::make_unique<
188                       orc::LocalIndirectStubsManager<orc::OrcMips32Be>>();
189       };
190 
191     case Triple::mipsel:
192       return [](){
193           return std::make_unique<
194                       orc::LocalIndirectStubsManager<orc::OrcMips32Le>>();
195       };
196 
197     case Triple::mips64:
198     case Triple::mips64el:
199       return [](){
200           return std::make_unique<
201                       orc::LocalIndirectStubsManager<orc::OrcMips64>>();
202       };
203 
204     case Triple::x86_64:
205       if (T.getOS() == Triple::OSType::Win32) {
206         return [](){
207           return std::make_unique<
208                      orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>();
209         };
210       } else {
211         return [](){
212           return std::make_unique<
213                      orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>();
214         };
215       }
216 
217   }
218 }
219 
220 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) {
221   Constant *AddrIntVal =
222     ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr);
223   Constant *AddrPtrVal =
224     ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal,
225                           PointerType::get(&FT, 0));
226   return AddrPtrVal;
227 }
228 
229 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
230                                   const Twine &Name, Constant *Initializer) {
231   auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage,
232                                Initializer, Name, nullptr,
233                                GlobalValue::NotThreadLocal, 0, true);
234   IP->setVisibility(GlobalValue::HiddenVisibility);
235   return IP;
236 }
237 
238 void makeStub(Function &F, Value &ImplPointer) {
239   assert(F.isDeclaration() && "Can't turn a definition into a stub.");
240   assert(F.getParent() && "Function isn't in a module.");
241   Module &M = *F.getParent();
242   BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F);
243   IRBuilder<> Builder(EntryBlock);
244   LoadInst *ImplAddr = Builder.CreateLoad(F.getType(), &ImplPointer);
245   std::vector<Value*> CallArgs;
246   for (auto &A : F.args())
247     CallArgs.push_back(&A);
248   CallInst *Call = Builder.CreateCall(F.getFunctionType(), ImplAddr, CallArgs);
249   Call->setTailCall();
250   Call->setAttributes(F.getAttributes());
251   if (F.getReturnType()->isVoidTy())
252     Builder.CreateRetVoid();
253   else
254     Builder.CreateRet(Call);
255 }
256 
257 std::vector<GlobalValue *> SymbolLinkagePromoter::operator()(Module &M) {
258   std::vector<GlobalValue *> PromotedGlobals;
259 
260   for (auto &GV : M.global_values()) {
261     bool Promoted = true;
262 
263     // Rename if necessary.
264     if (!GV.hasName())
265       GV.setName("__orc_anon." + Twine(NextId++));
266     else if (GV.getName().startswith("\01L"))
267       GV.setName("__" + GV.getName().substr(1) + "." + Twine(NextId++));
268     else if (GV.hasLocalLinkage())
269       GV.setName("__orc_lcl." + GV.getName() + "." + Twine(NextId++));
270     else
271       Promoted = false;
272 
273     if (GV.hasLocalLinkage()) {
274       GV.setLinkage(GlobalValue::ExternalLinkage);
275       GV.setVisibility(GlobalValue::HiddenVisibility);
276       Promoted = true;
277     }
278     GV.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
279 
280     if (Promoted)
281       PromotedGlobals.push_back(&GV);
282   }
283 
284   return PromotedGlobals;
285 }
286 
287 Function* cloneFunctionDecl(Module &Dst, const Function &F,
288                             ValueToValueMapTy *VMap) {
289   Function *NewF =
290     Function::Create(cast<FunctionType>(F.getValueType()),
291                      F.getLinkage(), F.getName(), &Dst);
292   NewF->copyAttributesFrom(&F);
293 
294   if (VMap) {
295     (*VMap)[&F] = NewF;
296     auto NewArgI = NewF->arg_begin();
297     for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE;
298          ++ArgI, ++NewArgI)
299       (*VMap)[&*ArgI] = &*NewArgI;
300   }
301 
302   return NewF;
303 }
304 
305 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
306                       ValueMaterializer *Materializer,
307                       Function *NewF) {
308   assert(!OrigF.isDeclaration() && "Nothing to move");
309   if (!NewF)
310     NewF = cast<Function>(VMap[&OrigF]);
311   else
312     assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap.");
313   assert(NewF && "Function mapping missing from VMap.");
314   assert(NewF->getParent() != OrigF.getParent() &&
315          "moveFunctionBody should only be used to move bodies between "
316          "modules.");
317 
318   SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned.
319   CloneFunctionInto(NewF, &OrigF, VMap, /*ModuleLevelChanges=*/true, Returns,
320                     "", nullptr, nullptr, Materializer);
321   OrigF.deleteBody();
322 }
323 
324 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
325                                         ValueToValueMapTy *VMap) {
326   GlobalVariable *NewGV = new GlobalVariable(
327       Dst, GV.getValueType(), GV.isConstant(),
328       GV.getLinkage(), nullptr, GV.getName(), nullptr,
329       GV.getThreadLocalMode(), GV.getType()->getAddressSpace());
330   NewGV->copyAttributesFrom(&GV);
331   if (VMap)
332     (*VMap)[&GV] = NewGV;
333   return NewGV;
334 }
335 
336 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
337                                    ValueToValueMapTy &VMap,
338                                    ValueMaterializer *Materializer,
339                                    GlobalVariable *NewGV) {
340   assert(OrigGV.hasInitializer() && "Nothing to move");
341   if (!NewGV)
342     NewGV = cast<GlobalVariable>(VMap[&OrigGV]);
343   else
344     assert(VMap[&OrigGV] == NewGV &&
345            "Incorrect global variable mapping in VMap.");
346   assert(NewGV->getParent() != OrigGV.getParent() &&
347          "moveGlobalVariableInitializer should only be used to move "
348          "initializers between modules");
349 
350   NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None,
351                                  nullptr, Materializer));
352 }
353 
354 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
355                                   ValueToValueMapTy &VMap) {
356   assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?");
357   auto *NewA = GlobalAlias::create(OrigA.getValueType(),
358                                    OrigA.getType()->getPointerAddressSpace(),
359                                    OrigA.getLinkage(), OrigA.getName(), &Dst);
360   NewA->copyAttributesFrom(&OrigA);
361   VMap[&OrigA] = NewA;
362   return NewA;
363 }
364 
365 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src,
366                               ValueToValueMapTy &VMap) {
367   auto *MFs = Src.getModuleFlagsMetadata();
368   if (!MFs)
369     return;
370   for (auto *MF : MFs->operands())
371     Dst.addModuleFlag(MapMetadata(MF, VMap));
372 }
373 
374 } // End namespace orc.
375 } // End namespace llvm.
376