## ALP Programming Guide and Reference

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### Description

The LOOP instruction decrements the count register without changing any of the flags. Conditions are then checked for the form of the LOOP instruction being used. If the conditions are met, a short jump is made to the label given by the operand to the LOOP instruction. If the address-size attribute is 16-bits, the CX register is used as the count register; otherwise the ECX register is used. The operand of the LOOP instruction must be in the range from 128 (decimal) bytes before the instruction to 127 bytes ahead of the instruction.

The LOOP instructions provide iteration control and combine loop index management with conditional branching. Use the LOOP instruction by loading an unsigned iteration count into the count register, then code the LOOP instruction at the end of a series of instructions to be iterated. The destination of the LOOP instruction is a label that points to the beginning of the iteration.