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KORTESTB

Performs a logical AND operation between a source operand and a destination operand of size 1 byte, updating the ZF, SF, and PF flags based on the result. The destination operand is not modified.

The following table covers the supported source and destination operands:

DO NOT support LOCK

This instruction is available in 64-bit mode and compatibility mode.

The instruction does not modify the destination operand; it only affects the CPU flags. This allows for testing a bitmask against a value without altering the original data. Ensure that the operand size is strictly 1 byte to avoid unintended memory access or incorrect flag updates.