llvm-6502/include/llvm/ExecutionEngine/SectionMemoryManager.h
Filip Pizlo a4ea4a7203 Put RTDyldMemoryManager into its own file, and make it linked into
libExecutionEngine. Move method implementations that aren't specific to 
allocation out of SectionMemoryManager and into RTDyldMemoryManager.

This is in preparation for exposing RTDyldMemoryManager through the C 
API.

This is a fixed version of r182407 and r182411. That first revision 
broke builds because I forgot to move the conditional includes of 
various POSIX headers from SectionMemoryManager into 
RTDyldMemoryManager. Those includes are necessary because of how 
getPointerToNamedFunction works around the glibc libc_nonshared.a thing. 
The latter revision still broke things because I forgot to include 
llvm/Config/config.h.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182418 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-21 20:24:07 +00:00

107 lines
4.3 KiB
C++

//===- SectionMemoryManager.h - Memory manager for MCJIT/RtDyld -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of a section-based memory manager used by
// the MCJIT execution engine and RuntimeDyld.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_EXECUTIONENGINE_SECTIONMEMORYMANAGER_H
#define LLVM_EXECUTIONENGINE_SECTIONMEMORYMANAGER_H
#include "llvm/ADT/SmallVector.h"
#include "llvm/ExecutionEngine/RuntimeDyld.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Memory.h"
namespace llvm {
/// This is a simple memory manager which implements the methods called by
/// the RuntimeDyld class to allocate memory for section-based loading of
/// objects, usually those generated by the MCJIT execution engine.
///
/// This memory manager allocates all section memory as read-write. The
/// RuntimeDyld will copy JITed section memory into these allocated blocks
/// and perform any necessary linking and relocations.
///
/// Any client using this memory manager MUST ensure that section-specific
/// page permissions have been applied before attempting to execute functions
/// in the JITed object. Permissions can be applied either by calling
/// MCJIT::finalizeObject or by calling SectionMemoryManager::finalizeMemory
/// directly. Clients of MCJIT should call MCJIT::finalizeObject.
class SectionMemoryManager : public RTDyldMemoryManager {
SectionMemoryManager(const SectionMemoryManager&) LLVM_DELETED_FUNCTION;
void operator=(const SectionMemoryManager&) LLVM_DELETED_FUNCTION;
public:
SectionMemoryManager() { }
virtual ~SectionMemoryManager();
/// \brief Allocates a memory block of (at least) the given size suitable for
/// executable code.
///
/// The value of \p Alignment must be a power of two. If \p Alignment is zero
/// a default alignment of 16 will be used.
virtual uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
unsigned SectionID);
/// \brief Allocates a memory block of (at least) the given size suitable for
/// executable code.
///
/// The value of \p Alignment must be a power of two. If \p Alignment is zero
/// a default alignment of 16 will be used.
virtual uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
unsigned SectionID,
bool isReadOnly);
/// \brief Update section-specific memory permissions and other attributes.
///
/// This method is called when object loading is complete and section page
/// permissions can be applied. It is up to the memory manager implementation
/// to decide whether or not to act on this method. The memory manager will
/// typically allocate all sections as read-write and then apply specific
/// permissions when this method is called. Code sections cannot be executed
/// until this function has been called. In addition, any cache coherency
/// operations needed to reliably use the memory are also performed.
///
/// \returns true if an error occurred, false otherwise.
virtual bool finalizeMemory(std::string *ErrMsg = 0);
/// \brief Invalidate instruction cache for code sections.
///
/// Some platforms with separate data cache and instruction cache require
/// explicit cache flush, otherwise JIT code manipulations (like resolved
/// relocations) will get to the data cache but not to the instruction cache.
///
/// This method is called from finalizeMemory.
virtual void invalidateInstructionCache();
private:
struct MemoryGroup {
SmallVector<sys::MemoryBlock, 16> AllocatedMem;
SmallVector<sys::MemoryBlock, 16> FreeMem;
sys::MemoryBlock Near;
};
uint8_t *allocateSection(MemoryGroup &MemGroup, uintptr_t Size,
unsigned Alignment);
error_code applyMemoryGroupPermissions(MemoryGroup &MemGroup,
unsigned Permissions);
MemoryGroup CodeMem;
MemoryGroup RWDataMem;
MemoryGroup RODataMem;
};
}
#endif // LLVM_EXECUTION_ENGINE_SECTION_MEMORY_MANAGER_H