B.4.179. `MOVSD': Move Scalar Double-Precision FP Value
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MOVSD xmm1,xmm2/m64 ; F2 0F 10 /r [WILLAMETTE,SSE2]
MOVSD xmm1/m64,xmm2 ; F2 0F 11 /r [WILLAMETTE,SSE2]
`MOVSD' moves a double-precision FP value from the source operand to
the destination operand. When the source or destination is a register,
the low-order FP value is read or written.