LLVM  8.0.1
RTDyldMemoryManager.h
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1 //===-- RTDyldMemoryManager.cpp - Memory manager for MC-JIT -----*- C++ -*-===//
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 // Interface of the runtime dynamic memory manager base class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_EXECUTIONENGINE_RTDYLDMEMORYMANAGER_H
15 #define LLVM_EXECUTIONENGINE_RTDYLDMEMORYMANAGER_H
16 
17 #include "llvm-c/ExecutionEngine.h"
21 #include <cstddef>
22 #include <cstdint>
23 #include <string>
24 
25 namespace llvm {
26 
27 class ExecutionEngine;
28 
29 namespace object {
30  class ObjectFile;
31 } // end namespace object
32 
34 public:
35  // Don't hide the notifyObjectLoaded method from RuntimeDyld::MemoryManager.
37 
38  /// This method is called after an object has been loaded into memory but
39  /// before relocations are applied to the loaded sections. The object load
40  /// may have been initiated by MCJIT to resolve an external symbol for another
41  /// object that is being finalized. In that case, the object about which
42  /// the memory manager is being notified will be finalized immediately after
43  /// the memory manager returns from this call.
44  ///
45  /// Memory managers which are preparing code for execution in an external
46  /// address space can use this call to remap the section addresses for the
47  /// newly loaded object.
49  const object::ObjectFile &) {}
50 
51 private:
52  void anchor() override;
53 };
54 
55 // RuntimeDyld clients often want to handle the memory management of
56 // what gets placed where. For JIT clients, this is the subset of
57 // JITMemoryManager required for dynamic loading of binaries.
58 //
59 // FIXME: As the RuntimeDyld fills out, additional routines will be needed
60 // for the varying types of objects to be allocated.
63 public:
64  RTDyldMemoryManager() = default;
66  void operator=(const RTDyldMemoryManager&) = delete;
67  ~RTDyldMemoryManager() override;
68 
69  /// Register EH frames in the current process.
70  static void registerEHFramesInProcess(uint8_t *Addr, size_t Size);
71 
72  /// Deregister EH frames in the current proces.
73  static void deregisterEHFramesInProcess(uint8_t *Addr, size_t Size);
74 
75  void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size) override;
76  void deregisterEHFrames() override;
77 
78  /// This method returns the address of the specified function or variable in
79  /// the current process.
80  static uint64_t getSymbolAddressInProcess(const std::string &Name);
81 
82  /// Legacy symbol lookup - DEPRECATED! Please override findSymbol instead.
83  ///
84  /// This method returns the address of the specified function or variable.
85  /// It is used to resolve symbols during module linking.
86  virtual uint64_t getSymbolAddress(const std::string &Name) {
87  return getSymbolAddressInProcess(Name);
88  }
89 
90  /// This method returns a RuntimeDyld::SymbolInfo for the specified function
91  /// or variable. It is used to resolve symbols during module linking.
92  ///
93  /// By default this falls back on the legacy lookup method:
94  /// 'getSymbolAddress'. The address returned by getSymbolAddress is treated as
95  /// a strong, exported symbol, consistent with historical treatment by
96  /// RuntimeDyld.
97  ///
98  /// Clients writing custom RTDyldMemoryManagers are encouraged to override
99  /// this method and return a SymbolInfo with the flags set correctly. This is
100  /// necessary for RuntimeDyld to correctly handle weak and non-exported symbols.
101  JITSymbol findSymbol(const std::string &Name) override {
102  return JITSymbol(getSymbolAddress(Name), JITSymbolFlags::Exported);
103  }
104 
105  /// Legacy symbol lookup -- DEPRECATED! Please override
106  /// findSymbolInLogicalDylib instead.
107  ///
108  /// Default to treating all modules as separate.
109  virtual uint64_t getSymbolAddressInLogicalDylib(const std::string &Name) {
110  return 0;
111  }
112 
113  /// Default to treating all modules as separate.
114  ///
115  /// By default this falls back on the legacy lookup method:
116  /// 'getSymbolAddressInLogicalDylib'. The address returned by
117  /// getSymbolAddressInLogicalDylib is treated as a strong, exported symbol,
118  /// consistent with historical treatment by RuntimeDyld.
119  ///
120  /// Clients writing custom RTDyldMemoryManagers are encouraged to override
121  /// this method and return a SymbolInfo with the flags set correctly. This is
122  /// necessary for RuntimeDyld to correctly handle weak and non-exported symbols.
123  JITSymbol
124  findSymbolInLogicalDylib(const std::string &Name) override {
125  return JITSymbol(getSymbolAddressInLogicalDylib(Name),
127  }
128 
129  /// This method returns the address of the specified function. As such it is
130  /// only useful for resolving library symbols, not code generated symbols.
131  ///
132  /// If \p AbortOnFailure is false and no function with the given name is
133  /// found, this function returns a null pointer. Otherwise, it prints a
134  /// message to stderr and aborts.
135  ///
136  /// This function is deprecated for memory managers to be used with
137  /// MCJIT or RuntimeDyld. Use getSymbolAddress instead.
138  virtual void *getPointerToNamedFunction(const std::string &Name,
139  bool AbortOnFailure = true);
140 
141 protected:
142  struct EHFrame {
143  uint8_t *Addr;
144  size_t Size;
145  };
146  typedef std::vector<EHFrame> EHFrameInfos;
147  EHFrameInfos EHFrames;
148 
149 private:
150  void anchor() override;
151 };
152 
153 // Create wrappers for C Binding types (see CBindingWrapping.h).
156 
157 } // end namespace llvm
158 
159 #endif // LLVM_EXECUTIONENGINE_RTDYLDMEMORYMANAGER_H
Represents a symbol in the JIT.
Definition: JITSymbol.h:238
This class represents lattice values for constants.
Definition: AllocatorList.h:24
virtual uint64_t getSymbolAddress(const std::string &Name)
Legacy symbol lookup - DEPRECATED! Please override findSymbol instead.
Legacy symbol resolution interface.
Definition: JITSymbol.h:371
This class is the base class for all object file types.
Definition: ObjectFile.h:202
amdgpu Simplify well known AMD library false Value Value const Twine & Name
struct LLVMOpaqueMCJITMemoryManager * LLVMMCJITMemoryManagerRef
#define DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ty, ref)
virtual void notifyObjectLoaded(ExecutionEngine *EE, const object::ObjectFile &)
This method is called after an object has been loaded into memory but before relocations are applied ...
JITSymbol findSymbol(const std::string &Name) override
This method returns a RuntimeDyld::SymbolInfo for the specified function or variable.
virtual void notifyObjectLoaded(RuntimeDyld &RTDyld, const object::ObjectFile &Obj)
This method is called after an object has been loaded into memory but before relocations are applied ...
Definition: RuntimeDyld.h:164
Abstract interface for implementation execution of LLVM modules, designed to support both interpreter...
virtual uint64_t getSymbolAddressInLogicalDylib(const std::string &Name)
Legacy symbol lookup – DEPRECATED! Please override findSymbolInLogicalDylib instead.
std::vector< EHFrame > EHFrameInfos
uint32_t Size
Definition: Profile.cpp:47
JITSymbol findSymbolInLogicalDylib(const std::string &Name) override
Default to treating all modules as separate.