1 //===-- RTDyldMemoryManager.cpp - Memory manager for MC-JIT -----*- 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 // Interface of the runtime dynamic memory manager base class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_EXECUTIONENGINE_RTDYLDMEMORYMANAGER_H
15 #define LLVM_EXECUTIONENGINE_RTDYLDMEMORYMANAGER_H
17 #include "llvm-c/ExecutionEngine.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/Support/CBindingWrapping.h"
20 #include "llvm/Support/Memory.h"
24 class ExecutionEngine;
27 uint64_t getSymbolAddress(const std::string &Name);
29 // RuntimeDyld clients often want to handle the memory management of
30 // what gets placed where. For JIT clients, this is the subset of
31 // JITMemoryManager required for dynamic loading of binaries.
33 // FIXME: As the RuntimeDyld fills out, additional routines will be needed
34 // for the varying types of objects to be allocated.
35 class RTDyldMemoryManager {
36 RTDyldMemoryManager(const RTDyldMemoryManager&) LLVM_DELETED_FUNCTION;
37 void operator=(const RTDyldMemoryManager&) LLVM_DELETED_FUNCTION;
39 RTDyldMemoryManager() {}
40 virtual ~RTDyldMemoryManager();
42 /// Allocate a memory block of (at least) the given size suitable for
43 /// executable code. The SectionID is a unique identifier assigned by the JIT
44 /// engine, and optionally recorded by the memory manager to access a loaded
46 virtual uint8_t *allocateCodeSection(
47 uintptr_t Size, unsigned Alignment, unsigned SectionID,
48 StringRef SectionName) = 0;
50 /// Allocate a memory block of (at least) the given size suitable for data.
51 /// The SectionID is a unique identifier assigned by the JIT engine, and
52 /// optionally recorded by the memory manager to access a loaded section.
53 virtual uint8_t *allocateDataSection(
54 uintptr_t Size, unsigned Alignment, unsigned SectionID,
55 StringRef SectionName, bool IsReadOnly) = 0;
57 /// Inform the memory manager about the total amount of memory required to
58 /// allocate all sections to be loaded:
59 /// \p CodeSize - the total size of all code sections
60 /// \p DataSizeRO - the total size of all read-only data sections
61 /// \p DataSizeRW - the total size of all read-write data sections
63 /// Note that by default the callback is disabled. To enable it
64 /// redefine the method needsToReserveAllocationSpace to return true.
65 virtual void reserveAllocationSpace(
66 uintptr_t CodeSize, uintptr_t DataSizeRO, uintptr_t DataSizeRW) { }
68 /// Override to return true to enable the reserveAllocationSpace callback.
69 virtual bool needsToReserveAllocationSpace() { return false; }
71 /// Register the EH frames with the runtime so that c++ exceptions work.
73 /// \p Addr parameter provides the local address of the EH frame section
74 /// data, while \p LoadAddr provides the address of the data in the target
75 /// address space. If the section has not been remapped (which will usually
76 /// be the case for local execution) these two values will be the same.
77 virtual void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size);
79 virtual void deregisterEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size);
81 /// This method returns the address of the specified function or variable.
82 /// It is used to resolve symbols during module linking.
83 virtual uint64_t getSymbolAddress(const std::string &Name) {
84 return llvm::getSymbolAddress(Name);
87 /// This method returns the address of the specified function. As such it is
88 /// only useful for resolving library symbols, not code generated symbols.
90 /// If \p AbortOnFailure is false and no function with the given name is
91 /// found, this function returns a null pointer. Otherwise, it prints a
92 /// message to stderr and aborts.
94 /// This function is deprecated for memory managers to be used with
95 /// MCJIT or RuntimeDyld. Use getSymbolAddress instead.
96 virtual void *getPointerToNamedFunction(const std::string &Name,
97 bool AbortOnFailure = true);
99 /// This method is called after an object has been loaded into memory but
100 /// before relocations are applied to the loaded sections. The object load
101 /// may have been initiated by MCJIT to resolve an external symbol for another
102 /// object that is being finalized. In that case, the object about which
103 /// the memory manager is being notified will be finalized immediately after
104 /// the memory manager returns from this call.
106 /// Memory managers which are preparing code for execution in an external
107 /// address space can use this call to remap the section addresses for the
108 /// newly loaded object.
109 virtual void notifyObjectLoaded(ExecutionEngine *EE,
110 const ObjectImage *) {}
112 /// This method is called when object loading is complete and section page
113 /// permissions can be applied. It is up to the memory manager implementation
114 /// to decide whether or not to act on this method. The memory manager will
115 /// typically allocate all sections as read-write and then apply specific
116 /// permissions when this method is called. Code sections cannot be executed
117 /// until this function has been called. In addition, any cache coherency
118 /// operations needed to reliably use the memory are also performed.
120 /// Returns true if an error occurred, false otherwise.
121 virtual bool finalizeMemory(std::string *ErrMsg = nullptr) = 0;
124 // Create wrappers for C Binding types (see CBindingWrapping.h).
125 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(
126 RTDyldMemoryManager, LLVMMCJITMemoryManagerRef)