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/Transforms/Utils/Cloning.h"
17 #include <sstream>
18 
19 namespace llvm {
20 namespace orc {
21 
22 void JITCompileCallbackManager::anchor() {}
23 void IndirectStubsManager::anchor() {}
24 
25 std::unique_ptr<JITCompileCallbackManager>
26 createLocalCompileCallbackManager(const Triple &T,
27                                   JITTargetAddress ErrorHandlerAddress) {
28   switch (T.getArch()) {
29     default: return nullptr;
30 
31     case Triple::aarch64: {
32       typedef orc::LocalJITCompileCallbackManager<orc::OrcAArch64> CCMgrT;
33       return llvm::make_unique<CCMgrT>(ErrorHandlerAddress);
34     }
35 
36     case Triple::x86: {
37       typedef orc::LocalJITCompileCallbackManager<orc::OrcI386> CCMgrT;
38       return llvm::make_unique<CCMgrT>(ErrorHandlerAddress);
39     }
40 
41     case Triple::x86_64: {
42       if ( T.getOS() == Triple::OSType::Win32 ) {
43         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT;
44         return llvm::make_unique<CCMgrT>(ErrorHandlerAddress);
45       } else {
46         typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT;
47         return llvm::make_unique<CCMgrT>(ErrorHandlerAddress);
48       }
49     }
50 
51   }
52 }
53 
54 std::function<std::unique_ptr<IndirectStubsManager>()>
55 createLocalIndirectStubsManagerBuilder(const Triple &T) {
56   switch (T.getArch()) {
57     default: return nullptr;
58 
59     case Triple::aarch64:
60       return [](){
61         return llvm::make_unique<
62                        orc::LocalIndirectStubsManager<orc::OrcAArch64>>();
63       };
64 
65     case Triple::x86:
66       return [](){
67         return llvm::make_unique<
68                        orc::LocalIndirectStubsManager<orc::OrcI386>>();
69       };
70 
71     case Triple::x86_64:
72       if (T.getOS() == Triple::OSType::Win32) {
73         return [](){
74           return llvm::make_unique<
75                      orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>();
76         };
77       } else {
78         return [](){
79           return llvm::make_unique<
80                      orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>();
81         };
82       }
83 
84   }
85 }
86 
87 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) {
88   Constant *AddrIntVal =
89     ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr);
90   Constant *AddrPtrVal =
91     ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal,
92                           PointerType::get(&FT, 0));
93   return AddrPtrVal;
94 }
95 
96 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
97                                   const Twine &Name, Constant *Initializer) {
98   auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage,
99                                Initializer, Name, nullptr,
100                                GlobalValue::NotThreadLocal, 0, true);
101   IP->setVisibility(GlobalValue::HiddenVisibility);
102   return IP;
103 }
104 
105 void makeStub(Function &F, Value &ImplPointer) {
106   assert(F.isDeclaration() && "Can't turn a definition into a stub.");
107   assert(F.getParent() && "Function isn't in a module.");
108   Module &M = *F.getParent();
109   BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F);
110   IRBuilder<> Builder(EntryBlock);
111   LoadInst *ImplAddr = Builder.CreateLoad(&ImplPointer);
112   std::vector<Value*> CallArgs;
113   for (auto &A : F.args())
114     CallArgs.push_back(&A);
115   CallInst *Call = Builder.CreateCall(ImplAddr, CallArgs);
116   Call->setTailCall();
117   Call->setAttributes(F.getAttributes());
118   if (F.getReturnType()->isVoidTy())
119     Builder.CreateRetVoid();
120   else
121     Builder.CreateRet(Call);
122 }
123 
124 // Utility class for renaming global values and functions during partitioning.
125 class GlobalRenamer {
126 public:
127 
128   static bool needsRenaming(const Value &New) {
129     return !New.hasName() || New.getName().startswith("\01L");
130   }
131 
132   const std::string& getRename(const Value &Orig) {
133     // See if we have a name for this global.
134     {
135       auto I = Names.find(&Orig);
136       if (I != Names.end())
137         return I->second;
138     }
139 
140     // Nope. Create a new one.
141     // FIXME: Use a more robust uniquing scheme. (This may blow up if the user
142     //        writes a "__orc_anon[[:digit:]]* method).
143     unsigned ID = Names.size();
144     std::ostringstream NameStream;
145     NameStream << "__orc_anon" << ID++;
146     auto I = Names.insert(std::make_pair(&Orig, NameStream.str()));
147     return I.first->second;
148   }
149 private:
150   DenseMap<const Value*, std::string> Names;
151 };
152 
153 static void raiseVisibilityOnValue(GlobalValue &V, GlobalRenamer &R) {
154   if (V.hasLocalLinkage()) {
155     if (R.needsRenaming(V))
156       V.setName(R.getRename(V));
157     V.setLinkage(GlobalValue::ExternalLinkage);
158     V.setVisibility(GlobalValue::HiddenVisibility);
159   }
160   V.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
161   assert(!R.needsRenaming(V) && "Invalid global name.");
162 }
163 
164 void makeAllSymbolsExternallyAccessible(Module &M) {
165   GlobalRenamer Renamer;
166 
167   for (auto &F : M)
168     raiseVisibilityOnValue(F, Renamer);
169 
170   for (auto &GV : M.globals())
171     raiseVisibilityOnValue(GV, Renamer);
172 
173   for (auto &A : M.aliases())
174     raiseVisibilityOnValue(A, Renamer);
175 }
176 
177 Function* cloneFunctionDecl(Module &Dst, const Function &F,
178                             ValueToValueMapTy *VMap) {
179   assert(F.getParent() != &Dst && "Can't copy decl over existing function.");
180   Function *NewF =
181     Function::Create(cast<FunctionType>(F.getValueType()),
182                      F.getLinkage(), F.getName(), &Dst);
183   NewF->copyAttributesFrom(&F);
184 
185   if (VMap) {
186     (*VMap)[&F] = NewF;
187     auto NewArgI = NewF->arg_begin();
188     for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE;
189          ++ArgI, ++NewArgI)
190       (*VMap)[&*ArgI] = &*NewArgI;
191   }
192 
193   return NewF;
194 }
195 
196 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
197                       ValueMaterializer *Materializer,
198                       Function *NewF) {
199   assert(!OrigF.isDeclaration() && "Nothing to move");
200   if (!NewF)
201     NewF = cast<Function>(VMap[&OrigF]);
202   else
203     assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap.");
204   assert(NewF && "Function mapping missing from VMap.");
205   assert(NewF->getParent() != OrigF.getParent() &&
206          "moveFunctionBody should only be used to move bodies between "
207          "modules.");
208 
209   SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned.
210   CloneFunctionInto(NewF, &OrigF, VMap, /*ModuleLevelChanges=*/true, Returns,
211                     "", nullptr, nullptr, Materializer);
212   OrigF.deleteBody();
213 }
214 
215 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
216                                         ValueToValueMapTy *VMap) {
217   assert(GV.getParent() != &Dst && "Can't copy decl over existing global var.");
218   GlobalVariable *NewGV = new GlobalVariable(
219       Dst, GV.getValueType(), GV.isConstant(),
220       GV.getLinkage(), nullptr, GV.getName(), nullptr,
221       GV.getThreadLocalMode(), GV.getType()->getAddressSpace());
222   NewGV->copyAttributesFrom(&GV);
223   if (VMap)
224     (*VMap)[&GV] = NewGV;
225   return NewGV;
226 }
227 
228 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
229                                    ValueToValueMapTy &VMap,
230                                    ValueMaterializer *Materializer,
231                                    GlobalVariable *NewGV) {
232   assert(OrigGV.hasInitializer() && "Nothing to move");
233   if (!NewGV)
234     NewGV = cast<GlobalVariable>(VMap[&OrigGV]);
235   else
236     assert(VMap[&OrigGV] == NewGV &&
237            "Incorrect global variable mapping in VMap.");
238   assert(NewGV->getParent() != OrigGV.getParent() &&
239          "moveGlobalVariable should only be used to move initializers between "
240          "modules");
241 
242   NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None,
243                                  nullptr, Materializer));
244 }
245 
246 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
247                                   ValueToValueMapTy &VMap) {
248   assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?");
249   auto *NewA = GlobalAlias::create(OrigA.getValueType(),
250                                    OrigA.getType()->getPointerAddressSpace(),
251                                    OrigA.getLinkage(), OrigA.getName(), &Dst);
252   NewA->copyAttributesFrom(&OrigA);
253   VMap[&OrigA] = NewA;
254   return NewA;
255 }
256 
257 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src,
258                               ValueToValueMapTy &VMap) {
259   auto *MFs = Src.getModuleFlagsMetadata();
260   if (!MFs)
261     return;
262   for (auto *MF : MFs->operands())
263     Dst.addModuleFlag(MapMetadata(MF, VMap));
264 }
265 
266 } // End namespace orc.
267 } // End namespace llvm.
268