Machinedependent

Machinedependent, also written machine-dependent, is an adjective used in computing to describe software, components, or code that relies on the specific hardware architecture on which it runs. This includes dependencies on processor type and instruction set, endianness, word size, memory alignment requirements, calling conventions, and operating system interfaces that differ across machines. As a result, machinedependent code may not execute correctly on hardware or systems with a different architecture without modification.

In practice, machinedependent code appears in low-level areas such as assembly language routines, architecture-specific optimizations, device drivers, and certain system libraries. It may also arise in parts of a program that directly manipulate hardware resources, rely on non-portable features, or depend on a particular Application Binary Interface (ABI). Such code tends to be faster or more efficient on the target machine but less portable.

Machinedependent code is contrasted with machine-independent or portable code, which uses standardized language features, portable libraries, and abstraction layers to run on multiple machines. Portability is often achieved by isolating hardware-specific logic behind interfaces, using conditional compilation or configuration, and adopting cross-platform standards.

In software engineering and compiler design, the term is used to describe areas where optimizations or code generation depend on the target architecture. Projects may manage machinedependent components with hardware abstraction layers, platform-specific modules, or virtualization to balance performance with portability.