image/svg+xmlFFREE—Free Floating-Point RegisterDescriptionSets the tag in the FPU tag register associated with register ST(i) to empty (11B). The contents of ST(i) and the FPU stack-top pointer (TOP) are not affected.This instruction’s operation is the same in non-64-bit modes and 64-bit mode.OperationTAG(i) := 11B;FPU Flags AffectedC0, C1, C2, C3 undefined.Floating-Point ExceptionsNoneProtected Mode Exceptions#NMCR0.EM[bit 2] or CR0.TS[bit 3] = 1.#MF If there is a pending x87 FPU exception.#UD If the LOCK prefix is used.Real-Address Mode ExceptionsSame exceptions as in protected mode.Virtual-8086 Mode ExceptionsSame exceptions as in protected mode.Compatibility Mode ExceptionsSame exceptions as in protected mode.64-Bit Mode ExceptionsSame exceptions as in protected mode.OpcodeInstruction64-Bit ModeCompat/Leg ModeDescriptionDD C0+iFFREE ST(i)ValidValidSets tag for ST(i) to empty.

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