This content has not been validated; it was AI-generated following the x86-64 ISA Documentation generation process to maintain high quality. However, as no human has verified this data, errors may exist. If the accuracy of this data is critical, please consult the Intel SDM. The model used to generate this is gemma4:31b

DAS

Decrements the destination operand by the value of the source operand.

The table after the description covers what the source and destinations can be.

DO NOT support LOCK

This instruction is NOT supported in 64-bit mode. It is only available in 16-bit and 32-bit compatibility modes.

The destination operand MUST be a register. Attempts to use a memory operand for the destination will result in an invalid operation.