This content has not been validated; it was AI-generated following the x86-64 ISA Documentation generation process to maintain high quality. However, as no human has verified this data, errors may exist. If the accuracy of this data is critical, please consult the Intel SDM. The model used to generate this is gemma4:31b

MOVSLDUP

Copies a doubleword value from a source to two packed doublewords in a destination. Specifically, it reads a dword from the source and duplicates it across the low and high dwords of a 64-bit destination.

The table after the description covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available in 64-bit mode or compatibility mode. It requires the destination operand to be an XMM register.

To avoid alignment exceptions, the memory source m4 SHOULD be aligned on a 4-byte boundary. Failure to do so MAY result in performance degradation or a general protection fault depending on the alignment check (AC) flag in the EFLAGS register.