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INSTRUCTION SET REFERENCE
UNPCKLPS—Unpack Low Packed Single-FP Data (Continued)
Protected Mode Exceptions
#GP(0)
For an illegal memory operand effective address in the CS, DS, ES, FS, or
GS segments.
#SS(0)
For an illegal address in the SS segment.
#PF(fault-code) For a page fault.
#UD
If CR0.EM = 1.
#NM
If TS bit in CR0 is set.
#UD
If CR4.OSFXSR(bit 9) = 0.
#UD
If CPUID.XMM(EDX bit 25) = 0.
Real Address Mode Exceptions
Interrupt 13
If any part of the operand would lie outside of the effective address space
from 0 to 0FFFFH.
#UD
If CR0.EM = 1.
#NM
If TS bit in CR0 is set.
#UD
If CR4.OSFXSR(bit 9) = 0.
#UD
If CPUID.XMM(EDX bit 25) = 0.
Virtual 8086 Mode Exceptions
Same exceptions as in Real Address Mode.
#PF(fault-code) For a page fault.
Comments
When unpacking from a memory operand, an implementation may decide to fetch only the
appropriate 64 bits. Alignment to 16-byte boundary and normal segment checking will still be
enforced.
The usage of Repeat Prefixes (F2H, F3H) with UNPCKLPS is reserved. Different processor
implementations may handle this prefix differently. Usage of these prefixes with UNPCKLPS
risks incompatibility with future processors.
