Min version	8.1	10 Pre RTM
Max version	8.1 Update 1	10 TH2
x64 offset offset:bitpos	Field Name
0x0000	struct _LIST_ENTRY ListEntry	struct _LIST_ENTRY ListEntry
0x0000		struct _SLIST_ENTRY Link
0x0010	struct _HEAP_LFH_SUBSEGMENT_OWNER * Owner
0x0010	union _HEAP_LFH_SUBSEGMENT_DELAY_FREE DelayFree
0x0018	struct _RTL_SRWLOCK BitmapLock	struct _RTL_SRWLOCK CommitLock
0x0020	struct _RTL_SRWLOCK CommitLock	uint16_t FreeCount
0x0020		volatile int16_t InterlockedShort
0x0020		volatile long InterlockedLong
0x0022		uint16_t BlockCount
0x0024		uint16_t FreeHint
0x0026		uint8_t Location
0x0027		uint8_t Spare
0x0028	uint16_t FreeCount	struct _HEAP_LFH_SUBSEGMENT_ENCODED_OFFSETS BlockOffsets
0x0028	volatile int16_t InterlockedShort
0x0028	volatile long InterlockedLong
0x002A	uint16_t BlockCount
0x002C	uint16_t FreeHint	uint8_t CommitUnitShift
0x002D		uint8_t CommitUnitCount
0x002E	uint16_t BlockSize	uint16_t CommitStateOffset
0x0030	unsigned long CommitBitmap	uint64_t[1] BlockBitmap
0x0034	uint16_t FirstBlockOffset
0x0036	uint8_t Location
0x0037	volatile uint8_t DecommitInProgress
0x0038	uint64_t[1] AllocationBitmap