Regtype

Regtype is a term used in computer science to describe a descriptor attached to a register in low-level code representations. It denotes the kind of data a register is intended to hold and informs the generation and validation of instructions. In practice, regtype helps compilers and runtimes perform type-safe code generation, optimize register usage, and prevent invalid operations.

In many register-based intermediate representations, each temporary or virtual register carries a regtype such as integer, floating-point, vector, or pointer/reference. This information guides instruction selection (for example, choosing an integer add versus a floating-point add) and enforces that only compatible operations are performed on a given register. Regtypes may also distinguish signed and unsigned integers or different bit widths.

Usage of regtype varies by system and is not universally standardized. Some architectures or compiler pipelines use different terminology such as register class, data type, or value type. Implementation often uses tags, enums, or a separate type system that is linked to SSA values and the register allocator. In JIT compilers and VM runtimes, regtype information can be used at runtime for type checks and to emit appropriate machine code or bytecode.

See also: register allocation, intermediate representation, type system, SSA, instruction selection, register class.