A hardware description language (HDL) is a computer language used to programmatically generate digital hardware.
The term is typically reserved for languages that target the register transfer level and the designs written in those are commonly referred to as RTL.
Typical HDLs for digital circuits include Verilog, SystemVerilog, and VHDL. Another notable example is SystemC, more intended for system modelling.
CodAL is not a HDL. Instead, CodAL is an ADL (Architecture Description Language). Even though they are similar, HDLs are different from ADLs as they are more low-level and do not have a description that covers software development tools. Expressing a processor in an HDL instantly requires significantly more effort than using an ADL specifically designed to describe processors, such as Codasip’s CodAL language. Designing and optimizing a processor in CodAL is much more efficient than doing it in an HDL. How much more efficient? We can use the following analogy: similar to how much easier it is to write an application in C/C++ vs. in assembler code.
