1f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar//===- llvm/Support/Memory.h - Memory Support -------------------*- C++ -*-===// 263b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 3e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer// The LLVM Compiler Infrastructure 4e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer// 57ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// This file is distributed under the University of Illinois Open Source 67ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// License. See LICENSE.TXT for details. 763b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 8e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer//===----------------------------------------------------------------------===// 9e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer// 10e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer// This file declares the llvm::sys::Memory class. 11e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer// 12e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer//===----------------------------------------------------------------------===// 13e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer 14674be02d525d4e24bc6943ed9274958c580bcfbcJakub Staszak#ifndef LLVM_SUPPORT_MEMORY_H 15674be02d525d4e24bc6943ed9274958c580bcfbcJakub Staszak#define LLVM_SUPPORT_MEMORY_H 16e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer 171f6efa3996dd1929fbc129203ce5009b620e6969Michael J. Spencer#include "llvm/Support/DataTypes.h" 18bed22d89020ea8a46c48bc1aa6128321a445dbb2Chris Lattner#include <string> 19c6a4f5e819217e1e12c458aed8e7b122e23a3a58Stephen Hines#include <system_error> 20bed22d89020ea8a46c48bc1aa6128321a445dbb2Chris Lattner 21e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencernamespace llvm { 22e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencernamespace sys { 23e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer 2433189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// This class encapsulates the notion of a memory block which has an address 2533189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// and a size. It is used by the Memory class (a friend) as the result of 2633189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// various memory allocation operations. 2733189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// @see Memory 2833189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// @brief Memory block abstraction. 2933189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer class MemoryBlock { 3033189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer public: 31dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines MemoryBlock() : Address(nullptr), Size(0) { } 3210b4fc552f984dc978298d50c09c97c0764962fcReid Kleckner MemoryBlock(void *addr, size_t size) : Address(addr), Size(size) { } 33bed22d89020ea8a46c48bc1aa6128321a445dbb2Chris Lattner void *base() const { return Address; } 3410b4fc552f984dc978298d50c09c97c0764962fcReid Kleckner size_t size() const { return Size; } 35f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar 3633189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer private: 37bed22d89020ea8a46c48bc1aa6128321a445dbb2Chris Lattner void *Address; ///< Address of first byte of memory area 3810b4fc552f984dc978298d50c09c97c0764962fcReid Kleckner size_t Size; ///< Size, in bytes of the memory area 3933189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer friend class Memory; 4033189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer }; 4133189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer 4233189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// This class provides various memory handling functions that manipulate 4333189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// MemoryBlock instances. 44e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer /// @since 1.4 4533189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer /// @brief An abstraction for memory operations. 46e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer class Memory { 4793bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner public: 48bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor enum ProtectionFlags { 49bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor MF_READ = 0x1000000, 50bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor MF_WRITE = 0x2000000, 51bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor MF_EXEC = 0x4000000 52bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor }; 53bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor 54bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// This method allocates a block of memory that is suitable for loading 55bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// dynamically generated code (e.g. JIT). An attempt to allocate 56bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p NumBytes bytes of virtual memory is made. 57bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p NearBlock may point to an existing allocation in which case 58bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// an attempt is made to allocate more memory near the existing block. 59bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// The actual allocated address is not guaranteed to be near the requested 60bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// address. 61bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p Flags is used to set the initial protection flags for the block 62bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// of the memory. 63bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p EC [out] returns an object describing any error that occurs. 64bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 65bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// This method may allocate more than the number of bytes requested. The 66bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// actual number of bytes allocated is indicated in the returned 67bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// MemoryBlock. 68bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 69bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// The start of the allocated block must be aligned with the 70bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// system allocation granularity (64K on Windows, page size on Linux). 71bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// If the address following \p NearBlock is not so aligned, it will be 72bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// rounded up to the next allocation granularity boundary. 73bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 74f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar /// \r a non-null MemoryBlock if the function was successful, 75bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// otherwise a null MemoryBlock is with \p EC describing the error. 76bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 77bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// @brief Allocate mapped memory. 78bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor static MemoryBlock allocateMappedMemory(size_t NumBytes, 79bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor const MemoryBlock *const NearBlock, 80bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor unsigned Flags, 81c6a4f5e819217e1e12c458aed8e7b122e23a3a58Stephen Hines std::error_code &EC); 82bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor 83bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// This method releases a block of memory that was allocated with the 84bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// allocateMappedMemory method. It should not be used to release any 85bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// memory block allocated any other way. 86bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p Block describes the memory to be released. 87bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 88bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \r error_success if the function was successful, or an error_code 89bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// describing the failure if an error occurred. 90f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar /// 91bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// @brief Release mapped memory. 92c6a4f5e819217e1e12c458aed8e7b122e23a3a58Stephen Hines static std::error_code releaseMappedMemory(MemoryBlock &Block); 93bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor 94bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// This method sets the protection flags for a block of memory to the 95bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// state specified by /p Flags. The behavior is not specified if the 96bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// memory was not allocated using the allocateMappedMemory method. 97bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p Block describes the memory block to be protected. 98bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \p Flags specifies the new protection state to be assigned to the block. 9936b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines /// \p ErrMsg [out] returns a string describing any error that occurred. 100bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 101bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// If \p Flags is MF_WRITE, the actual behavior varies 102652b28dbcac156bb6a3b596bdf29aaf17e89eda5Andrew Kaylor /// with the operating system (i.e. MF_READ | MF_WRITE on Windows) and the 103652b28dbcac156bb6a3b596bdf29aaf17e89eda5Andrew Kaylor /// target architecture (i.e. MF_WRITE -> MF_READ | MF_WRITE on i386). 104bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 105bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// \r error_success if the function was successful, or an error_code 106bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// describing the failure if an error occurred. 107bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// 108bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor /// @brief Set memory protection state. 109c6a4f5e819217e1e12c458aed8e7b122e23a3a58Stephen Hines static std::error_code protectMappedMemory(const MemoryBlock &Block, 110c6a4f5e819217e1e12c458aed8e7b122e23a3a58Stephen Hines unsigned Flags); 111bbf628b6cefc8d817eb9ec04c2a357ad3f27d618Andrew Kaylor 11293bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// This method allocates a block of Read/Write/Execute memory that is 11393bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// suitable for executing dynamically generated code (e.g. JIT). An 11493bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// attempt to allocate \p NumBytes bytes of virtual memory is made. 11593bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// \p NearBlock may point to an existing allocation in which case 11693bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// an attempt is made to allocate more memory near the existing block. 11793bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// 11893bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// On success, this returns a non-null memory block, otherwise it returns 11993bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// a null memory block and fills in *ErrMsg. 1201f6efa3996dd1929fbc129203ce5009b620e6969Michael J. Spencer /// 12193bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// @brief Allocate Read/Write/Execute memory. 12210b4fc552f984dc978298d50c09c97c0764962fcReid Kleckner static MemoryBlock AllocateRWX(size_t NumBytes, 12393bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner const MemoryBlock *NearBlock, 124dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines std::string *ErrMsg = nullptr); 12533189e787b98c79bd03be466ec19dfb2f65eb65fReid Spencer 12693bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// This method releases a block of Read/Write/Execute memory that was 12793bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// allocated with the AllocateRWX method. It should not be used to 12893bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// release any memory block allocated any other way. 12993bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// 13093bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// On success, this returns false, otherwise it returns true and fills 13193bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// in *ErrMsg. 13293bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// @brief Release Read/Write/Execute memory. 133dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines static bool ReleaseRWX(MemoryBlock &block, std::string *ErrMsg = nullptr); 1341f6efa3996dd1929fbc129203ce5009b620e6969Michael J. Spencer 13593bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// InvalidateInstructionCache - Before the JIT can run a block of code 13693bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// that has been emitted it must invalidate the instruction cache on some 13793bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner /// platforms. 13893bb4aa0ce43bea18401e2444bf6d34af19c6084Chris Lattner static void InvalidateInstructionCache(const void *Addr, size_t Len); 139bc4707a2554ac04ba006bf70035e7bc7270236a9Evan Cheng 140cce6c297c54b4c9c8615c77e97cd64e70812ea60Jim Grosbach /// setExecutable - Before the JIT can run a block of code, it has to be 141bc4707a2554ac04ba006bf70035e7bc7270236a9Evan Cheng /// given read and executable privilege. Return true if it is already r-x 142bc4707a2554ac04ba006bf70035e7bc7270236a9Evan Cheng /// or the system is able to change its previlege. 143dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines static bool setExecutable(MemoryBlock &M, std::string *ErrMsg = nullptr); 144cce6c297c54b4c9c8615c77e97cd64e70812ea60Jim Grosbach 145cce6c297c54b4c9c8615c77e97cd64e70812ea60Jim Grosbach /// setWritable - When adding to a block of code, the JIT may need 146cce6c297c54b4c9c8615c77e97cd64e70812ea60Jim Grosbach /// to mark a block of code as RW since the protections are on page 147cce6c297c54b4c9c8615c77e97cd64e70812ea60Jim Grosbach /// boundaries, and the JIT internal allocations are not page aligned. 148dce4a407a24b04eebc6a376f8e62b41aaa7b071fStephen Hines static bool setWritable(MemoryBlock &M, std::string *ErrMsg = nullptr); 149932a32d2512353478d16c4101582adff404a55a5Jim Grosbach 1501f6efa3996dd1929fbc129203ce5009b620e6969Michael J. Spencer /// setRangeExecutable - Mark the page containing a range of addresses 151932a32d2512353478d16c4101582adff404a55a5Jim Grosbach /// as executable. 152932a32d2512353478d16c4101582adff404a55a5Jim Grosbach static bool setRangeExecutable(const void *Addr, size_t Size); 153932a32d2512353478d16c4101582adff404a55a5Jim Grosbach 1541f6efa3996dd1929fbc129203ce5009b620e6969Michael J. Spencer /// setRangeWritable - Mark the page containing a range of addresses 155932a32d2512353478d16c4101582adff404a55a5Jim Grosbach /// as writable. 156932a32d2512353478d16c4101582adff404a55a5Jim Grosbach static bool setRangeWritable(const void *Addr, size_t Size); 157e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer }; 158f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar 159f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar /// Owning version of MemoryBlock. 160f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar class OwningMemoryBlock { 161f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar public: 162f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar OwningMemoryBlock() = default; 163f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar explicit OwningMemoryBlock(MemoryBlock M) : M(M) {} 164f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar OwningMemoryBlock(OwningMemoryBlock &&Other) { 165f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar M = Other.M; 166f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar Other.M = MemoryBlock(); 167f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar } 168f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar OwningMemoryBlock& operator=(OwningMemoryBlock &&Other) { 169f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar M = Other.M; 170f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar Other.M = MemoryBlock(); 171f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar return *this; 172f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar } 173f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar ~OwningMemoryBlock() { 174f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar Memory::releaseMappedMemory(M); 175f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar } 176f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar void *base() const { return M.base(); } 177f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar size_t size() const { return M.size(); } 178f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar MemoryBlock getMemoryBlock() const { return M; } 179f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar private: 180f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar MemoryBlock M; 181f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar }; 182f3ef5332fa3f4d5ec72c178a2b19dac363a19383Pirama Arumuga Nainar 183e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer} 184e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer} 185e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer 186e5d6ca43d71e9e541d2b515c954406cb9a199446Reid Spencer#endif 187