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BLSI

Extracts the lowest set bit of the source operand and clears it from the destination operand.

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

DO NOT support LOCK

This instruction is ONLY available in 64-bit mode. It is NOT supported in compatibility mode or 32-bit mode.

The instruction requires the BMI1 extension to be supported by the processor; execution on a processor lacking this feature WILL result in an invalid opcode exception. The operation does not affect any EFLAGS register bits.