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:
58       return [](){
59         return llvm::make_unique<
60                        orc::LocalIndirectStubsManager<orc::OrcGenericABI>>();
61       };
62 
63     case Triple::aarch64:
64       return [](){
65         return llvm::make_unique<
66                        orc::LocalIndirectStubsManager<orc::OrcAArch64>>();
67       };
68 
69     case Triple::x86:
70       return [](){
71         return llvm::make_unique<
72                        orc::LocalIndirectStubsManager<orc::OrcI386>>();
73       };
74 
75     case Triple::x86_64:
76       if (T.getOS() == Triple::OSType::Win32) {
77         return [](){
78           return llvm::make_unique<
79                      orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>();
80         };
81       } else {
82         return [](){
83           return llvm::make_unique<
84                      orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>();
85         };
86       }
87 
88   }
89 }
90 
91 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) {
92   Constant *AddrIntVal =
93     ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr);
94   Constant *AddrPtrVal =
95     ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal,
96                           PointerType::get(&FT, 0));
97   return AddrPtrVal;
98 }
99 
100 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
101                                   const Twine &Name, Constant *Initializer) {
102   auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage,
103                                Initializer, Name, nullptr,
104                                GlobalValue::NotThreadLocal, 0, true);
105   IP->setVisibility(GlobalValue::HiddenVisibility);
106   return IP;
107 }
108 
109 void makeStub(Function &F, Value &ImplPointer) {
110   assert(F.isDeclaration() && "Can't turn a definition into a stub.");
111   assert(F.getParent() && "Function isn't in a module.");
112   Module &M = *F.getParent();
113   BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F);
114   IRBuilder<> Builder(EntryBlock);
115   LoadInst *ImplAddr = Builder.CreateLoad(&ImplPointer);
116   std::vector<Value*> CallArgs;
117   for (auto &A : F.args())
118     CallArgs.push_back(&A);
119   CallInst *Call = Builder.CreateCall(ImplAddr, CallArgs);
120   Call->setTailCall();
121   Call->setAttributes(F.getAttributes());
122   if (F.getReturnType()->isVoidTy())
123     Builder.CreateRetVoid();
124   else
125     Builder.CreateRet(Call);
126 }
127 
128 // Utility class for renaming global values and functions during partitioning.
129 class GlobalRenamer {
130 public:
131 
132   static bool needsRenaming(const Value &New) {
133     return !New.hasName() || New.getName().startswith("\01L");
134   }
135 
136   const std::string& getRename(const Value &Orig) {
137     // See if we have a name for this global.
138     {
139       auto I = Names.find(&Orig);
140       if (I != Names.end())
141         return I->second;
142     }
143 
144     // Nope. Create a new one.
145     // FIXME: Use a more robust uniquing scheme. (This may blow up if the user
146     //        writes a "__orc_anon[[:digit:]]* method).
147     unsigned ID = Names.size();
148     std::ostringstream NameStream;
149     NameStream << "__orc_anon" << ID++;
150     auto I = Names.insert(std::make_pair(&Orig, NameStream.str()));
151     return I.first->second;
152   }
153 private:
154   DenseMap<const Value*, std::string> Names;
155 };
156 
157 static void raiseVisibilityOnValue(GlobalValue &V, GlobalRenamer &R) {
158   if (V.hasLocalLinkage()) {
159     if (R.needsRenaming(V))
160       V.setName(R.getRename(V));
161     V.setLinkage(GlobalValue::ExternalLinkage);
162     V.setVisibility(GlobalValue::HiddenVisibility);
163   }
164   V.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
165   assert(!R.needsRenaming(V) && "Invalid global name.");
166 }
167 
168 void makeAllSymbolsExternallyAccessible(Module &M) {
169   GlobalRenamer Renamer;
170 
171   for (auto &F : M)
172     raiseVisibilityOnValue(F, Renamer);
173 
174   for (auto &GV : M.globals())
175     raiseVisibilityOnValue(GV, Renamer);
176 
177   for (auto &A : M.aliases())
178     raiseVisibilityOnValue(A, Renamer);
179 }
180 
181 Function* cloneFunctionDecl(Module &Dst, const Function &F,
182                             ValueToValueMapTy *VMap) {
183   assert(F.getParent() != &Dst && "Can't copy decl over existing function.");
184   Function *NewF =
185     Function::Create(cast<FunctionType>(F.getValueType()),
186                      F.getLinkage(), F.getName(), &Dst);
187   NewF->copyAttributesFrom(&F);
188 
189   if (VMap) {
190     (*VMap)[&F] = NewF;
191     auto NewArgI = NewF->arg_begin();
192     for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE;
193          ++ArgI, ++NewArgI)
194       (*VMap)[&*ArgI] = &*NewArgI;
195   }
196 
197   return NewF;
198 }
199 
200 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
201                       ValueMaterializer *Materializer,
202                       Function *NewF) {
203   assert(!OrigF.isDeclaration() && "Nothing to move");
204   if (!NewF)
205     NewF = cast<Function>(VMap[&OrigF]);
206   else
207     assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap.");
208   assert(NewF && "Function mapping missing from VMap.");
209   assert(NewF->getParent() != OrigF.getParent() &&
210          "moveFunctionBody should only be used to move bodies between "
211          "modules.");
212 
213   SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned.
214   CloneFunctionInto(NewF, &OrigF, VMap, /*ModuleLevelChanges=*/true, Returns,
215                     "", nullptr, nullptr, Materializer);
216   OrigF.deleteBody();
217 }
218 
219 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
220                                         ValueToValueMapTy *VMap) {
221   assert(GV.getParent() != &Dst && "Can't copy decl over existing global var.");
222   GlobalVariable *NewGV = new GlobalVariable(
223       Dst, GV.getValueType(), GV.isConstant(),
224       GV.getLinkage(), nullptr, GV.getName(), nullptr,
225       GV.getThreadLocalMode(), GV.getType()->getAddressSpace());
226   NewGV->copyAttributesFrom(&GV);
227   if (VMap)
228     (*VMap)[&GV] = NewGV;
229   return NewGV;
230 }
231 
232 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
233                                    ValueToValueMapTy &VMap,
234                                    ValueMaterializer *Materializer,
235                                    GlobalVariable *NewGV) {
236   assert(OrigGV.hasInitializer() && "Nothing to move");
237   if (!NewGV)
238     NewGV = cast<GlobalVariable>(VMap[&OrigGV]);
239   else
240     assert(VMap[&OrigGV] == NewGV &&
241            "Incorrect global variable mapping in VMap.");
242   assert(NewGV->getParent() != OrigGV.getParent() &&
243          "moveGlobalVariable should only be used to move initializers between "
244          "modules");
245 
246   NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None,
247                                  nullptr, Materializer));
248 }
249 
250 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
251                                   ValueToValueMapTy &VMap) {
252   assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?");
253   auto *NewA = GlobalAlias::create(OrigA.getValueType(),
254                                    OrigA.getType()->getPointerAddressSpace(),
255                                    OrigA.getLinkage(), OrigA.getName(), &Dst);
256   NewA->copyAttributesFrom(&OrigA);
257   VMap[&OrigA] = NewA;
258   return NewA;
259 }
260 
261 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src,
262                               ValueToValueMapTy &VMap) {
263   auto *MFs = Src.getModuleFlagsMetadata();
264   if (!MFs)
265     return;
266   for (auto *MF : MFs->operands())
267     Dst.addModuleFlag(MapMetadata(MF, VMap));
268 }
269 
270 } // End namespace orc.
271 } // End namespace llvm.
272