DLX

DLX
DesignerJohn L. Hennessy and David A. Patterson
Bits32-bit
Introduced1994
Version1.0
DesignRISC
TypeLoad–store
EncodingFixed
BranchingCondition register
EndiannessBi-endian
ExtensionsNone, but MDMX & MIPS-3D could be used
OpenYes
Registers
General-purpose32 (R0=0)
Floating point32 (paired DP for 32-bit)

The DLX (pronounced "Deluxe") is a RISC processor architecture designed by John L. Hennessy and David A. Patterson, the principal designers of the Stanford MIPS and the Berkeley RISC designs (respectively), the two benchmark examples of RISC design (named after the Berkeley design).

The DLX is essentially a cleaned up (and modernized) simplified Stanford MIPS CPU. The DLX has a simple 32-bit load/store architecture, somewhat unlike the modern MIPS architecture CPU. As the DLX was intended primarily for teaching purposes, the DLX design is widely used in university-level computer architecture courses.

There are two known "softcore" hardware implementations: ASPIDA and VAMP. The ASPIDA project resulted in a core with many nice features: it is open source, supports Wishbone, has an asynchronous design, supports multiple ISAs, and is ASIC proven. VAMP is a DLX-variant that was mathematically verified as part of Verisoft project. It was specified with PVS, implemented in Verilog, and runs on a Xilinx FPGA. A full stack from compiler to kernel to TCP/IP was built on it.