diff options
Diffstat (limited to 'include/llvm/Support/Memory.h')
| -rw-r--r-- | include/llvm/Support/Memory.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/include/llvm/Support/Memory.h b/include/llvm/Support/Memory.h index 37890e7..025eee7 100644 --- a/include/llvm/Support/Memory.h +++ b/include/llvm/Support/Memory.h @@ -15,6 +15,7 @@ #define LLVM_SYSTEM_MEMORY_H #include "llvm/Support/DataTypes.h" +#include "llvm/Support/system_error.h" #include <string> namespace llvm { @@ -43,6 +44,70 @@ namespace sys { /// @brief An abstraction for memory operations. class Memory { public: + enum ProtectionFlags { + MF_READ = 0x1000000, + MF_WRITE = 0x2000000, + MF_EXEC = 0x4000000 + }; + + /// This method allocates a block of memory that is suitable for loading + /// dynamically generated code (e.g. JIT). An attempt to allocate + /// \p NumBytes bytes of virtual memory is made. + /// \p NearBlock may point to an existing allocation in which case + /// an attempt is made to allocate more memory near the existing block. + /// The actual allocated address is not guaranteed to be near the requested + /// address. + /// \p Flags is used to set the initial protection flags for the block + /// of the memory. + /// \p EC [out] returns an object describing any error that occurs. + /// + /// This method may allocate more than the number of bytes requested. The + /// actual number of bytes allocated is indicated in the returned + /// MemoryBlock. + /// + /// The start of the allocated block must be aligned with the + /// system allocation granularity (64K on Windows, page size on Linux). + /// If the address following \p NearBlock is not so aligned, it will be + /// rounded up to the next allocation granularity boundary. + /// + /// \r a non-null MemoryBlock if the function was successful, + /// otherwise a null MemoryBlock is with \p EC describing the error. + /// + /// @brief Allocate mapped memory. + static MemoryBlock allocateMappedMemory(size_t NumBytes, + const MemoryBlock *const NearBlock, + unsigned Flags, + error_code &EC); + + /// This method releases a block of memory that was allocated with the + /// allocateMappedMemory method. It should not be used to release any + /// memory block allocated any other way. + /// \p Block describes the memory to be released. + /// + /// \r error_success if the function was successful, or an error_code + /// describing the failure if an error occurred. + /// + /// @brief Release mapped memory. + static error_code releaseMappedMemory(MemoryBlock &Block); + + /// This method sets the protection flags for a block of memory to the + /// state specified by /p Flags. The behavior is not specified if the + /// memory was not allocated using the allocateMappedMemory method. + /// \p Block describes the memory block to be protected. + /// \p Flags specifies the new protection state to be assigned to the block. + /// \p ErrMsg [out] returns a string describing any error that occured. + /// + /// If \p Flags is MF_WRITE, the actual behavior varies + /// with the operating system (i.e. MF_READ | MF_WRITE on Windows) and the + /// target architecture (i.e. MF_WRITE -> MF_READ | MF_WRITE on i386). + /// + /// \r error_success if the function was successful, or an error_code + /// describing the failure if an error occurred. + /// + /// @brief Set memory protection state. + static error_code protectMappedMemory(const MemoryBlock &Block, + unsigned Flags); + /// This method allocates a block of Read/Write/Execute memory that is /// suitable for executing dynamically generated code (e.g. JIT). An /// attempt to allocate \p NumBytes bytes of virtual memory is made. |
