Developer Guide and Reference

Contents

_xrstor64()/xrstors64()

Restores the states of x87 FPU, MMX, XMM, YMM, and MXCSR registers from memory.

Syntax

extern void _xrstor64(void *mem, unsigned __int64 rstor_mask);
extern void _xrstors64(const void *mem, unsigned __int64 rstor_mask);
Arguments
mem
A memory reference to
FXSAVE
area. The 512-bytes memory addressed by the reference must be 16-bytes aligned.
rstor_mask
A bit mask specifying the extended states to be restored.
Description
Restores the states of
x87 FPU
,
MMX
,
XMM
,
YMM
, and
MXCSR
registers from memory. The
xrstor64
intrinsic maps to
XRSTOR64
instruction, and the
xrstors64
intrinsic maps to
XRSTORS64
instruction. See the Intel® 64 and IA-32 Architectures Software Developer's Manual for information on how the instructions differ.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804