class Memory

Declaration

class Memory { /* full declaration omitted */ };

Description

This class provides various memory handling functions that manipulate MemoryBlock instances.

Declared at: llvm/include/llvm/Support/Memory.h:53

Method Overview

• public static void InvalidateInstructionCache(const void * Addr, size_t Len)
• public static llvm::sys::MemoryBlock allocateMappedMemory(size_t NumBytes, const llvm::sys::MemoryBlock *const NearBlock, unsigned int Flags, std::error_code & EC)
• public static std::error_code protectMappedMemory(const llvm::sys::MemoryBlock & Block, unsigned int Flags)
• public static std::error_code releaseMappedMemory(llvm::sys::MemoryBlock & Block)

Methods

¶static void InvalidateInstructionCache(
    const void* Addr,
    size_t Len)

Description

InvalidateInstructionCache - Before the JIT can run a block of code that has been emitted it must invalidate the instruction cache on some platforms.

Declared at: llvm/include/llvm/Support/Memory.h:135

Parameters

const void* Addr

size_t Len

¶static llvm::sys::MemoryBlock
allocateMappedMemory(
    size_t NumBytes,
    const llvm::sys::MemoryBlock* const NearBlock,
    unsigned int Flags,
    std::error_code& EC)

Description

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. \ra non-null MemoryBlock if the function was successful, otherwise a null MemoryBlock is with \p EC describing the error. Allocate mapped memory.

Declared at: llvm/include/llvm/Support/Memory.h:98

Parameters

size_t NumBytes

const llvm::sys::MemoryBlock* const NearBlock

unsigned int Flags

std::error_code& EC

¶static std::error_code protectMappedMemory(
    const llvm::sys::MemoryBlock& Block,
    unsigned int Flags)

Description

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 occurred. 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). \rerror_success if the function was successful, or an error_code describing the failure if an error occurred. Set memory protection state.

Declared at: llvm/include/llvm/Support/Memory.h:129

Parameters

const llvm::sys::MemoryBlock& Block

unsigned int Flags

¶static std::error_code releaseMappedMemory(
    llvm::sys::MemoryBlock& Block)

Description

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. \rerror_success if the function was successful, or an error_code describing the failure if an error occurred. Release mapped memory.

Declared at: llvm/include/llvm/Support/Memory.h:112

Parameters

llvm::sys::MemoryBlock& Block