registerbased

Registerbased refers to architectures and representations that use a fixed set of fast storage locations called registers as the primary place to hold operands and results during computation. In a registerbased system, most instructions specify registers directly, for example r1 = r2 + r3. This contrasts with stackbased models that operate on values pushed on a stack.

In hardware, registerbased processors dominate modern design. Processors such as x86-64, ARM, and RISC-V perform arithmetic and data movement primarily between registers, with memory references used mainly for loading and storing values. This model supports efficient pipelines, register renaming, and flexible instruction formats, though some architectures still allow memory operands.

In compiler design and virtual machines, registerbased representations use virtual registers rather than a stack. LLVM IR is a well-known example, using a continuous set of virtual registers (e.g., %0, %1). At code generation time, a register allocator maps virtual registers to a limited set of physical registers. By contrast, many legacy VMs such as the Java Virtual Machine employ a stackbased bytecode, while others like Dalvik and ART for Android use registerbased bytecodes.

Advantages of registerbased design include reduced memory traffic, more efficient instruction pipelines, and greater potential for optimization through register allocation and renaming. Disadvantages include increased architectural and compiler complexity, especially regarding register file size, calling conventions, and the cost of register allocation on smaller devices.

Common examples and related concepts include x86-64, ARM, RISC-V, LLVM IR; register allocation; static single assignment form; Dalvik and ART.