XSUSLDTRK - Suspend Tracking Load Addresses

Opcode/ Instruction

Op/ En

64/32 bit Mode Support

CPUID Feature Flag

Description

F2 0F 01 E8 XSUSLDTRK

ZO

V/V

TSXLDTRK

Specifies the start of an Intel TSX suspend read address tracking region.

Instruction Operand Encoding

Op/En

Tuple

Operand 1

Operand 2

Operand 3

Operand 4

ZO

N/A

N/A

N/A

N/A

N/A

Description

The instruction marks the start of an Intel TSX (RTM) suspend load address tracking region. If the instruction is used inside a transactional region, subsequent loads are not added to the read set of the transaction. If the instruc- tion is used inside a suspend load address tracking region it will cause transaction abort.

If the instruction is used outside of a transactional region it behaves like a NOP. Chapter 16, "Programming with Intel® Transactional Synchronization Extensions‚" in the Intel® 64 and IA-32

Architectures Software Developer's Manual, Volume 1 provides additional information on Intel® TSX Suspend Load Address Tracking.

Operation

XSUSLDTRK 

IF RTM_ACTIVE = 1:
   IF SUSLDTRK_ACTIVE = 0:
       SUSLDTRK_ACTIVE := 1
   ELSE:
       RTM_ABORT
ELSE:
   NOP

Flags Affected

None.

Intel C/C++ Compiler Intrinsic Equivalent 

XSUSLDTRK void _xsusldtrk(void);

SIMD Floating-Point Exceptions

None.

Other Exceptions

#UD

If CPUID.(EAX=7, ECX=0):EDX.TSXLDTRK[bit 16] = 0. If the LOCK prefix is used.