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MOVSS

Moves a scalar single-precision floating-point value from a source to a destination.

The following table covers what the source and destinations can be:

DO NOT support LOCK

This instruction requires SSE support. It is available in 64-bit mode, 32-bit mode, and compatibility mode.

When the destination is a memory operand (m4), the instruction only updates the first 4 bytes of the destination address; the remaining bytes of the memory location remain unchanged. The instruction does not trigger floating-point exceptions (#I, #Z, #D, #O, #U, #P) as it performs a raw data move without arithmetic processing. Using a non-aligned memory address may result in performance degradation or faults depending on the alignment check (AC) flag in the EFLAGS register.