1 //===-- IndirectionUtils.h - Utilities for adding indirections --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Contains utilities for adding indirections and breaking up modules.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_EXECUTIONENGINE_ORC_INDIRECTIONUTILS_H
15 #define LLVM_EXECUTIONENGINE_ORC_INDIRECTIONUTILS_H
17 #include "JITSymbol.h"
18 #include "LambdaResolver.h"
19 #include "llvm/ADT/DenseSet.h"
20 #include "llvm/ExecutionEngine/RuntimeDyld.h"
21 #include "llvm/IR/IRBuilder.h"
22 #include "llvm/IR/Mangler.h"
23 #include "llvm/IR/Module.h"
24 #include "llvm/Transforms/Utils/ValueMapper.h"
30 /// @brief Target-independent base class for compile callback management.
31 class JITCompileCallbackManager {
34 typedef std::function<TargetAddress()> CompileFtor;
36 /// @brief Handle to a newly created compile callback. Can be used to get an
37 /// IR constant representing the address of the trampoline, and to set
38 /// the compile action for the callback.
39 class CompileCallbackInfo {
41 CompileCallbackInfo(TargetAddress Addr, CompileFtor &Compile)
42 : Addr(Addr), Compile(Compile) {}
44 TargetAddress getAddress() const { return Addr; }
45 void setCompileAction(CompileFtor Compile) {
46 this->Compile = std::move(Compile);
53 /// @brief Construct a JITCompileCallbackManager.
54 /// @param ErrorHandlerAddress The address of an error handler in the target
55 /// process to be used if a compile callback fails.
56 JITCompileCallbackManager(TargetAddress ErrorHandlerAddress)
57 : ErrorHandlerAddress(ErrorHandlerAddress) {}
59 virtual ~JITCompileCallbackManager() {}
61 /// @brief Execute the callback for the given trampoline id. Called by the JIT
62 /// to compile functions on demand.
63 TargetAddress executeCompileCallback(TargetAddress TrampolineAddr) {
64 auto I = ActiveTrampolines.find(TrampolineAddr);
65 // FIXME: Also raise an error in the Orc error-handler when we finally have
67 if (I == ActiveTrampolines.end())
68 return ErrorHandlerAddress;
70 // Found a callback handler. Yank this trampoline out of the active list and
71 // put it back in the available trampolines list, then try to run the
72 // handler's compile and update actions.
73 // Moving the trampoline ID back to the available list first means there's at
74 // least one available trampoline if the compile action triggers a request for
76 auto Compile = std::move(I->second);
77 ActiveTrampolines.erase(I);
78 AvailableTrampolines.push_back(TrampolineAddr);
80 if (auto Addr = Compile())
83 return ErrorHandlerAddress;
86 /// @brief Reserve a compile callback.
87 CompileCallbackInfo getCompileCallback() {
88 TargetAddress TrampolineAddr = getAvailableTrampolineAddr();
89 auto &Compile = this->ActiveTrampolines[TrampolineAddr];
90 return CompileCallbackInfo(TrampolineAddr, Compile);
93 /// @brief Get a CompileCallbackInfo for an existing callback.
94 CompileCallbackInfo getCompileCallbackInfo(TargetAddress TrampolineAddr) {
95 auto I = ActiveTrampolines.find(TrampolineAddr);
96 assert(I != ActiveTrampolines.end() && "Not an active trampoline.");
97 return CompileCallbackInfo(I->first, I->second);
100 /// @brief Release a compile callback.
102 /// Note: Callbacks are auto-released after they execute. This method should
103 /// only be called to manually release a callback that is not going to
105 void releaseCompileCallback(TargetAddress TrampolineAddr) {
106 auto I = ActiveTrampolines.find(TrampolineAddr);
107 assert(I != ActiveTrampolines.end() && "Not an active trampoline.");
108 ActiveTrampolines.erase(I);
109 AvailableTrampolines.push_back(TrampolineAddr);
113 TargetAddress ErrorHandlerAddress;
115 typedef std::map<TargetAddress, CompileFtor> TrampolineMapT;
116 TrampolineMapT ActiveTrampolines;
117 std::vector<TargetAddress> AvailableTrampolines;
121 TargetAddress getAvailableTrampolineAddr() {
122 if (this->AvailableTrampolines.empty())
124 assert(!this->AvailableTrampolines.empty() &&
125 "Failed to grow available trampolines.");
126 TargetAddress TrampolineAddr = this->AvailableTrampolines.back();
127 this->AvailableTrampolines.pop_back();
128 return TrampolineAddr;
131 // Create new trampolines - to be implemented in subclasses.
132 virtual void grow() = 0;
134 virtual void anchor();
137 /// @brief Manage compile callbacks for in-process JITs.
138 template <typename TargetT>
139 class LocalJITCompileCallbackManager : public JITCompileCallbackManager {
142 /// @brief Construct a InProcessJITCompileCallbackManager.
143 /// @param ErrorHandlerAddress The address of an error handler in the target
144 /// process to be used if a compile callback fails.
145 LocalJITCompileCallbackManager(TargetAddress ErrorHandlerAddress)
146 : JITCompileCallbackManager(ErrorHandlerAddress) {
148 /// Set up the resolver block.
151 sys::OwningMemoryBlock(
152 sys::Memory::allocateMappedMemory(TargetT::ResolverCodeSize, nullptr,
153 sys::Memory::MF_READ |
154 sys::Memory::MF_WRITE, EC));
155 assert(!EC && "Failed to allocate resolver block");
157 TargetT::writeResolverCode(static_cast<uint8_t*>(ResolverBlock.base()),
160 EC = sys::Memory::protectMappedMemory(ResolverBlock.getMemoryBlock(),
161 sys::Memory::MF_READ |
162 sys::Memory::MF_EXEC);
163 assert(!EC && "Failed to mprotect resolver block");
168 static TargetAddress reenter(void *CCMgr, void *TrampolineId) {
169 JITCompileCallbackManager *Mgr =
170 static_cast<JITCompileCallbackManager*>(CCMgr);
171 return Mgr->executeCompileCallback(
172 static_cast<TargetAddress>(
173 reinterpret_cast<uintptr_t>(TrampolineId)));
176 void grow() override {
177 assert(this->AvailableTrampolines.empty() && "Growing prematurely?");
180 auto TrampolineBlock =
181 sys::OwningMemoryBlock(
182 sys::Memory::allocateMappedMemory(TargetT::PageSize, nullptr,
183 sys::Memory::MF_READ |
184 sys::Memory::MF_WRITE, EC));
185 assert(!EC && "Failed to allocate trampoline block");
188 unsigned NumTrampolines =
189 (TargetT::PageSize - TargetT::PointerSize) / TargetT::TrampolineSize;
191 uint8_t *TrampolineMem = static_cast<uint8_t*>(TrampolineBlock.base());
192 TargetT::writeTrampolines(TrampolineMem, ResolverBlock.base(),
195 for (unsigned I = 0; I < NumTrampolines; ++I)
196 this->AvailableTrampolines.push_back(
197 static_cast<TargetAddress>(
198 reinterpret_cast<uintptr_t>(
199 TrampolineMem + (I * TargetT::TrampolineSize))));
201 EC = sys::Memory::protectMappedMemory(TrampolineBlock.getMemoryBlock(),
202 sys::Memory::MF_READ |
203 sys::Memory::MF_EXEC);
204 assert(!EC && "Failed to mprotect trampoline block");
206 TrampolineBlocks.push_back(std::move(TrampolineBlock));
209 sys::OwningMemoryBlock ResolverBlock;
210 std::vector<sys::OwningMemoryBlock> TrampolineBlocks;
213 /// @brief Base class for managing collections of named indirect stubs.
214 class IndirectStubsManagerBase {
217 /// @brief Map type for initializing the manager. See init.
218 typedef StringMap<std::pair<TargetAddress, JITSymbolFlags>> StubInitsMap;
220 virtual ~IndirectStubsManagerBase() {}
222 /// @brief Create a single stub with the given name, target address and flags.
223 virtual std::error_code createStub(StringRef StubName, TargetAddress StubAddr,
224 JITSymbolFlags StubFlags) = 0;
226 /// @brief Create StubInits.size() stubs with the given names, target
227 /// addresses, and flags.
228 virtual std::error_code createStubs(const StubInitsMap &StubInits) = 0;
230 /// @brief Find the stub with the given name. If ExportedStubsOnly is true,
231 /// this will only return a result if the stub's flags indicate that it
233 virtual JITSymbol findStub(StringRef Name, bool ExportedStubsOnly) = 0;
235 /// @brief Find the implementation-pointer for the stub.
236 virtual JITSymbol findPointer(StringRef Name) = 0;
238 /// @brief Change the value of the implementation pointer for the stub.
239 virtual std::error_code updatePointer(StringRef Name, TargetAddress NewAddr) = 0;
241 virtual void anchor();
244 /// @brief IndirectStubsManager implementation for a concrete target, e.g.
245 /// OrcX86_64. (See OrcTargetSupport.h).
246 template <typename TargetT>
247 class IndirectStubsManager : public IndirectStubsManagerBase {
250 std::error_code createStub(StringRef StubName, TargetAddress StubAddr,
251 JITSymbolFlags StubFlags) override {
252 if (auto EC = reserveStubs(1))
255 createStubInternal(StubName, StubAddr, StubFlags);
257 return std::error_code();
260 std::error_code createStubs(const StubInitsMap &StubInits) override {
261 if (auto EC = reserveStubs(StubInits.size()))
264 for (auto &Entry : StubInits)
265 createStubInternal(Entry.first(), Entry.second.first,
266 Entry.second.second);
268 return std::error_code();
271 JITSymbol findStub(StringRef Name, bool ExportedStubsOnly) override {
272 auto I = StubIndexes.find(Name);
273 if (I == StubIndexes.end())
275 auto Key = I->second.first;
276 void *StubAddr = IndirectStubsInfos[Key.first].getStub(Key.second);
277 assert(StubAddr && "Missing stub address");
278 auto StubTargetAddr =
279 static_cast<TargetAddress>(reinterpret_cast<uintptr_t>(StubAddr));
280 auto StubSymbol = JITSymbol(StubTargetAddr, I->second.second);
281 if (ExportedStubsOnly && !StubSymbol.isExported())
286 JITSymbol findPointer(StringRef Name) override {
287 auto I = StubIndexes.find(Name);
288 if (I == StubIndexes.end())
290 auto Key = I->second.first;
291 void *PtrAddr = IndirectStubsInfos[Key.first].getPtr(Key.second);
292 assert(PtrAddr && "Missing pointer address");
294 static_cast<TargetAddress>(reinterpret_cast<uintptr_t>(PtrAddr));
295 return JITSymbol(PtrTargetAddr, I->second.second);
298 std::error_code updatePointer(StringRef Name, TargetAddress NewAddr) override {
299 auto I = StubIndexes.find(Name);
300 assert(I != StubIndexes.end() && "No stub pointer for symbol");
301 auto Key = I->second.first;
302 *IndirectStubsInfos[Key.first].getPtr(Key.second) =
303 reinterpret_cast<void*>(static_cast<uintptr_t>(NewAddr));
304 return std::error_code();
309 std::error_code reserveStubs(unsigned NumStubs) {
310 if (NumStubs <= FreeStubs.size())
311 return std::error_code();
313 unsigned NewStubsRequired = NumStubs - FreeStubs.size();
314 unsigned NewBlockId = IndirectStubsInfos.size();
315 typename TargetT::IndirectStubsInfo ISI;
316 if (auto EC = TargetT::emitIndirectStubsBlock(ISI, NewStubsRequired,
319 for (unsigned I = 0; I < ISI.getNumStubs(); ++I)
320 FreeStubs.push_back(std::make_pair(NewBlockId, I));
321 IndirectStubsInfos.push_back(std::move(ISI));
322 return std::error_code();
325 void createStubInternal(StringRef StubName, TargetAddress InitAddr,
326 JITSymbolFlags StubFlags) {
327 auto Key = FreeStubs.back();
328 FreeStubs.pop_back();
329 *IndirectStubsInfos[Key.first].getPtr(Key.second) =
330 reinterpret_cast<void*>(static_cast<uintptr_t>(InitAddr));
331 StubIndexes[StubName] = std::make_pair(Key, StubFlags);
334 std::vector<typename TargetT::IndirectStubsInfo> IndirectStubsInfos;
335 typedef std::pair<uint16_t, uint16_t> StubKey;
336 std::vector<StubKey> FreeStubs;
337 StringMap<std::pair<StubKey, JITSymbolFlags>> StubIndexes;
340 /// @brief Build a function pointer of FunctionType with the given constant
343 /// Usage example: Turn a trampoline address into a function pointer constant
344 /// for use in a stub.
345 Constant* createIRTypedAddress(FunctionType &FT, TargetAddress Addr);
347 /// @brief Create a function pointer with the given type, name, and initializer
348 /// in the given Module.
349 GlobalVariable* createImplPointer(PointerType &PT, Module &M,
350 const Twine &Name, Constant *Initializer);
352 /// @brief Turn a function declaration into a stub function that makes an
353 /// indirect call using the given function pointer.
354 void makeStub(Function &F, Value &ImplPointer);
356 /// @brief Raise linkage types and rename as necessary to ensure that all
357 /// symbols are accessible for other modules.
359 /// This should be called before partitioning a module to ensure that the
360 /// partitions retain access to each other's symbols.
361 void makeAllSymbolsExternallyAccessible(Module &M);
363 /// @brief Clone a function declaration into a new module.
365 /// This function can be used as the first step towards creating a callback
366 /// stub (see makeStub), or moving a function body (see moveFunctionBody).
368 /// If the VMap argument is non-null, a mapping will be added between F and
369 /// the new declaration, and between each of F's arguments and the new
370 /// declaration's arguments. This map can then be passed in to moveFunction to
371 /// move the function body if required. Note: When moving functions between
372 /// modules with these utilities, all decls should be cloned (and added to a
373 /// single VMap) before any bodies are moved. This will ensure that references
374 /// between functions all refer to the versions in the new module.
375 Function* cloneFunctionDecl(Module &Dst, const Function &F,
376 ValueToValueMapTy *VMap = nullptr);
378 /// @brief Move the body of function 'F' to a cloned function declaration in a
379 /// different module (See related cloneFunctionDecl).
381 /// If the target function declaration is not supplied via the NewF parameter
382 /// then it will be looked up via the VMap.
384 /// This will delete the body of function 'F' from its original parent module,
385 /// but leave its declaration.
386 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap,
387 ValueMaterializer *Materializer = nullptr,
388 Function *NewF = nullptr);
390 /// @brief Clone a global variable declaration into a new module.
391 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV,
392 ValueToValueMapTy *VMap = nullptr);
394 /// @brief Move global variable GV from its parent module to cloned global
395 /// declaration in a different module.
397 /// If the target global declaration is not supplied via the NewGV parameter
398 /// then it will be looked up via the VMap.
400 /// This will delete the initializer of GV from its original parent module,
401 /// but leave its declaration.
402 void moveGlobalVariableInitializer(GlobalVariable &OrigGV,
403 ValueToValueMapTy &VMap,
404 ValueMaterializer *Materializer = nullptr,
405 GlobalVariable *NewGV = nullptr);
408 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA,
409 ValueToValueMapTy &VMap);
411 } // End namespace orc.
412 } // End namespace llvm.
414 #endif // LLVM_EXECUTIONENGINE_ORC_INDIRECTIONUTILS_H