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FGenericPlatformMemory

Generic implementation for most platforms, these tend to be unused and unimplemented.

API > API/Runtime > API/Runtime/Core

Generic implementation for most platforms, these tend to be unused and unimplemented.

   
Name FGenericPlatformMemory
Type struct
Header File /Engine/Source/Runtime/Core/Public/GenericPlatform/GenericPlatformMemory.h
Include Path #include "GenericPlatform/GenericPlatformMemory.h"

Syntax

struct FGenericPlatformMemory

Derived Classes

Classes

Name Remarks
FBasicVirtualMemoryBlock  

Structs

Name Remarks
FSharedMemoryRegion Generic representation of a shared memory region

Enums

Public

Name Remarks
EMemoryAllocatorToUse Which allocator is being used
EMemoryCounterRegion Various memory regions that can be used with memory stats.
ESharedMemoryAccess Flags used for shared memory creation/open

Constants

Name Type Remarks Include Path
AllocatorToUse EMemoryAllocatorToUse Current allocator GenericPlatform/GenericPlatformMemory.h
BackupOOMMemoryPool void * Preallocated buffer to delete on out of memory. Used by OOM handling and crash reporting. GenericPlatform/GenericPlatformMemory.h
BackupOOMMemoryPoolSize uint32 Size of BackupOOMMemoryPool in bytes. GenericPlatform/GenericPlatformMemory.h
bIsOOM bool Set to true if we encounters out of memory. GenericPlatform/GenericPlatformMemory.h
OOMAllocationAlignment uint32 Set to alignment of allocation that triggered out of memory, zero otherwise. GenericPlatform/GenericPlatformMemory.h
OOMAllocationSize uint64 Set to size of allocation that triggered out of memory, zero otherwise. GenericPlatform/GenericPlatformMemory.h
ProgramSize uint64 Program memory allocation in bytes. GenericPlatform/GenericPlatformMemory.h

Functions

Static

Name Remarks Include Path Unreal Specifiers

static FMalloc * BaseAllocator()

   GenericPlatform/GenericPlatformMemory.h  

static void * BigBlockMemcpy ( void* Dest,
const void* Src,
SIZE_T Count
)

 Memcpy optimized for big blocks. GenericPlatform/GenericPlatformMemory.h  

static void * BinnedAllocFromOS ( SIZE_T Size
)

 Allocates pages from the OS. GenericPlatform/GenericPlatformMemory.h  

static void BinnedFreeToOS ( void* Ptr,
SIZE_T Size
)

 Returns pages allocated by BinnedAllocFromOS to the OS. GenericPlatform/GenericPlatformMemory.h  

static bool BinnedPlatformHasMemoryPoolForThisSize ( SIZE_T Size
)

 Some platforms may pool allocations of this size to reduce OS calls. GenericPlatform/GenericPlatformMemory.h  

static bool CanOverallocateVirtualMemory()

 Return true if the platform can allocate a lot more virtual memory than physical memory It's true for most platforms, but iOS needs a special entitlement and Linux a kernel config for this GenericPlatform/GenericPlatformMemory.h  

static void DumpPlatformAndAllocatorStats ( FOutputDevice& Ar
)

 Dumps basic platform memory statistics and allocator specific statistics into the specified output device. GenericPlatform/GenericPlatformMemory.h  

static void DumpStats ( FOutputDevice& Ar
)

 Dumps basic platform memory statistics into the specified output device. GenericPlatform/GenericPlatformMemory.h  

static uint32 GetBackMemoryPoolSize()

   GenericPlatform/GenericPlatformMemory.h  

static const FPlatformMemoryConstants & GetConstants()

   GenericPlatform/GenericPlatformMemory.h  
Returns >0 if debug memory has been assigned to the title for general use. GenericPlatform/GenericPlatformMemory.h  

static bool GetForkedPageAllocationInfo ( TArray< FForkedPageAllocation >& OutPageAllocationInfos
)

 Return the page allocations from the operating system (/proc/self/smaps). GenericPlatform/GenericPlatformMemory.h  

static bool GetLLMAllocFunctions ( void*(*&)(size_t) OutAllocFunction,
void(*&)(void*, size_t) OutFreeFunction,
int32& OutAlignment
)

 This function sets AllocFunction and FreeFunction and returns true, or just returns false. GenericPlatform/GenericPlatformMemory.h  

static EPlatformMemorySizeBucket GetMemorySizeBucket()

 Return which "high level", per platform, memory bucket we are in GenericPlatform/GenericPlatformMemory.h  

static uint64 GetMemoryUsedFast()

   GenericPlatform/GenericPlatformMemory.h  

static uint32 GetPhysicalGBRam()

   GenericPlatform/GenericPlatformMemory.h  

static uint64 GetProgramSize()

 Returns initial program size or 0 if the platform doesn't track initial program size GenericPlatform/GenericPlatformMemory.h  

static FPlatformMemoryStats GetStats()

   GenericPlatform/GenericPlatformMemory.h  

static void GetStatsForMallocProfiler ( FGenericMemoryStats& out_Stats
)

 Writes all platform specific current memory statistics in the format usable by the malloc profiler. GenericPlatform/GenericPlatformMemory.h  

static FPlatformMemoryStats GetStatsRaw()

   GenericPlatform/GenericPlatformMemory.h  

static bool HasForkPageProtectorEnabled()

 Returns true if Protecting the parent processes pages has been enabled Only supported on platforms that support forking GenericPlatform/GenericPlatformMemory.h  

static void Init()

 Initializes platform memory specific constants. GenericPlatform/GenericPlatformMemory.h  

static void InternalUpdateStats ( const FPlatformMemoryStats& MemoryStats
)

 Updates platform specific stats. GenericPlatform/GenericPlatformMemory.h  
Returns true if debug memory has been assigned to the title for general use. GenericPlatform/GenericPlatformMemory.h  

static bool IsNanoMallocAvailable()

 Nano Malloc is Apple's tiny block allocator. Does the Nano malloc zone exist? GenericPlatform/GenericPlatformMemory.h  

static FSharedMemoryRegion * MapNamedSharedMemoryRegion ( const FString& Name,
bool bCreate,
uint32 AccessMode,
SIZE_T Size
)

 Maps a named shared memory region into process address space (creates or opens it) GenericPlatform/GenericPlatformMemory.h  

static int32 Memcmp ( const void* Buf1,
const void* Buf2,
SIZE_T Count
)

   GenericPlatform/GenericPlatformMemory.h  

static void * Memcpy ( void* Dest,
const void* Src,
SIZE_T Count
)

   GenericPlatform/GenericPlatformMemory.h  

static void * Memmove ( void* Dest,
const void* Src,
SIZE_T Count
)

 Copies count bytes of characters from Src to Dest. GenericPlatform/GenericPlatformMemory.h  

static void * Memset ( void* Dest,
uint8 Char,
SIZE_T Count
)

   GenericPlatform/GenericPlatformMemory.h  

static void Memswap ( void* Ptr1,
void* Ptr2,
SIZE_T Size
)

   GenericPlatform/GenericPlatformMemory.h  

static void MemswapGreaterThan8 ( void* Ptr1,
void* Ptr2,
SIZE_T Size
)

   GenericPlatform/GenericPlatformMemory.h  

static void * Memzero ( void* Dest,
SIZE_T Count
)

   GenericPlatform/GenericPlatformMemory.h  

static void MiMallocInit ()

 Performs initial setup for MiMalloc. GenericPlatform/GenericPlatformMemory.h  

static void NanoMallocInit()

 Performs initial setup for Nano malloc. This is a noop on non-apple platforms GenericPlatform/GenericPlatformMemory.h  

static void OnLowLevelMemory_Alloc ( void const* Pointer,
uint64 Size,
uint64 Tag
)

 Called for all default tracker LLM allocations and frees, when LLM is enabled. GenericPlatform/GenericPlatformMemory.h  

static void OnLowLevelMemory_Free ( void const* Pointer,
uint64 Size,
uint64 Tag
)

   GenericPlatform/GenericPlatformMemory.h  

static void OnOutOfMemory ( uint64 Size,
uint32 Alignment
)

   GenericPlatform/GenericPlatformMemory.h  

static bool PageProtect ( void*const Ptr,
const SIZE_T Size,
const bool bCanRead,
const bool bCanWrite
)

 Changes the protection on a region of committed pages in the virtual address space. GenericPlatform/GenericPlatformMemory.h  

static void * ParallelMemcpy ( void* Dest,
const void* Src,
SIZE_T Count,
EMemcpyCachePolicy Policy
)

 On some platforms memcpy can be distributed over multiple threads for throughput. GenericPlatform/GenericPlatformMemory.h  

static FString PrettyMemory ( uint64 Memory
)

 Returns a pretty-string for an amount of memory given in bytes. GenericPlatform/GenericPlatformMemory.h  

static bool PtrIsFromNanoMalloc ( void* Ptr
)

 Was this pointer allocated by in the Nano Malloc Zone? Currently only Apple platforms implement this to detect small block allocations. GenericPlatform/GenericPlatformMemory.h  

static bool PtrIsOSMalloc ( void* Ptr
)

 Was this pointer allocated by the OS malloc? Currently only Apple platforms implement this to detect small block allocations. GenericPlatform/GenericPlatformMemory.h  

static T ReadUnaligned ( const void* Ptr
)

 Loads a simple POD type from unaligned memory. GenericPlatform/GenericPlatformMemory.h  

static void RegisterCustomLLMTags()

 Called once at LLM initialization time to let the platform add any custom tags GenericPlatform/GenericPlatformMemory.h  

static void SetProgramSize ( uint64 InProgramSize
)

 Sets the initial program size GenericPlatform/GenericPlatformMemory.h  

static void SetupMemoryPools()

 Initializes the memory pools, should be called by the init function. GenericPlatform/GenericPlatformMemory.h  

static void * StreamingMemcpy ( void* Dest,
const void* Src,
SIZE_T Count
)

 On some platforms memcpy optimized for big blocks that avoid L2 cache pollution are available GenericPlatform/GenericPlatformMemory.h  

static bool SupportsFastVRAMMemory()

 Gets whether this platform supports Fast VRAM memory Ie, whether TexCreate_FastVRAM flags actually mean something or not GenericPlatform/GenericPlatformMemory.h  

static bool TracksLLMAllocations ()

 Indicates whether LLM allocations are already accounted for with tracking and in GetStats. GenericPlatform/GenericPlatformMemory.h  

static bool UnmapNamedSharedMemoryRegion ( FSharedMemoryRegion* MemoryRegion
)

 Unmaps a name shared memory region GenericPlatform/GenericPlatformMemory.h  

static void UpdateCustomLLMTags ()

 Called once per frame when LLM is collating the data for the current frame. GenericPlatform/GenericPlatformMemory.h  

static void Valswap ( T& A,
T& B
)

   GenericPlatform/GenericPlatformMemory.h  

static void WriteUnaligned ( void* Ptr,
const T& InValue
)

 Stores a simple POD type to unaligned memory. GenericPlatform/GenericPlatformMemory.h  

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