MDMX
Encyclopedia
The MDMX also known as MaDMaX, is an extension to the MIPS
instruction set architecture (ISA) released in October 1996 at the Microprocessor Forum.
The media registers hold two new data types: octo byte (OB) and quad half (QH) that contain eight bytes (8-bit) and four halfwords (16-bit) integers.
Variants of existing instructions operate on these data types, performing saturating arithmetic, logical, shift, compare and align operations.
MDMX also introduced 19 instructions for permutation, manipulating bytes in registers, performing arithmetic with the accumulator, and accumulator access.
MIPS architecture
MIPS is a reduced instruction set computer instruction set architecture developed by MIPS Technologies . The early MIPS architectures were 32-bit, and later versions were 64-bit...
instruction set architecture (ISA) released in October 1996 at the Microprocessor Forum.
History
MDMX was developed to accelerate multimedia applications that were becoming more popular and common in the 1990s on RISC and CISC systems.Functionality
MDMX defines a new set of thirty-two 64-bit registers called media registers, which are mapped onto the existing floating-point registers to save hardware; and a 192-bit extended product accumulator.The media registers hold two new data types: octo byte (OB) and quad half (QH) that contain eight bytes (8-bit) and four halfwords (16-bit) integers.
Variants of existing instructions operate on these data types, performing saturating arithmetic, logical, shift, compare and align operations.
MDMX also introduced 19 instructions for permutation, manipulating bytes in registers, performing arithmetic with the accumulator, and accumulator access.