Visual Instruction Set, or VIS, is a

SIMD Single instruction, multiple data (SIMD) is a type of parallel processing in Flynn's taxonomy. SIMD can be internal (part of the hardware design) and it can be directly accessible through an instruction set architecture (ISA), but it shoul ...

instruction set extension for

SPARC V9 SPARC (Scalable Processor Architecture) is a reduced instruction set computer (RISC) instruction set architecture originally developed by Sun Microsystems. Its design was strongly influenced by the experimental Berkeley RISC system developed in ...

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circ ...

s developed by

Sun Microsystems Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, t ...

. There are five versions of VIS: VIS 1, VIS 2, VIS 2+, VIS 3 and VIS 4.

History

VIS 1 was introduced in 1994 and was first implemented by Sun in their

UltraSPARC The UltraSPARC is a microprocessor developed by Sun Microsystems and fabricated by Texas Instruments, introduced in mid-1995. It is the first microprocessor from Sun to implement the 64-bit SPARC V9 instruction set architecture (ISA). Marc Tre ...

microprocessor (1995) and by Fujitsu in their SPARC64 GP microprocessors (2000). VIS 2 was first implemented by the

UltraSPARC III The UltraSPARC III, code-named "Cheetah", is a microprocessor that implements the SPARC V9 instruction set architecture (ISA) developed by Sun Microsystems and fabricated by Texas Instruments. It was introduced in 2001 and operates at 600 to 90 ...

. All subsequent UltraSPARC and SPARC64 microprocessors implement the instruction set. VIS 3 was first implemented in the SPARC T4 microprocessor. VIS 4 was first implemented in the SPARC M7 microprocessor.

Differences vs x86

VIS is not an instruction toolkit like

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 ser ...

's MMX and SSE. MMX has only 8 registers shared with the FPU stack, while SPARC processors have 32 registers, also aliased to the double-precision (64-bit) floating point registers. As with the SIMD instruction set extensions on other

RISC In computer engineering, a reduced instruction set computer (RISC) is a computer designed to simplify the individual instructions given to the computer to accomplish tasks. Compared to the instructions given to a complex instruction set comp ...

processors, VIS strictly conforms to the main principle of RISC: keep the instruction set concise and efficient. This design is very different from comparable extensions on CISC processors, such as

MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...

, SSE,

SSE2 SSE2 (Streaming SIMD Extensions 2) is one of the Intel SIMD (Single Instruction, Multiple Data) processor supplementary instruction sets first introduced by Intel with the initial version of the Pentium 4 in 2000. It extends the earlier SSE i ...

SSE3 SSE3, Streaming SIMD Extensions 3, also known by its Intel code name Prescott New Instructions (PNI), is the third iteration of the SSE instruction set for the IA-32 (x86) architecture. Intel introduced SSE3 in early 2004 with the Prescott revis ...

SSE4 SSE4 (Streaming SIMD Extensions 4) is a SIMD CPU instruction set used in the Intel Core microarchitecture and AMD K10 (K8L). It was announced on September 27, 2006, at the Fall 2006 Intel Developer Forum, with vague details in a white paper; m ...

3DNow! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...

. Sometimes, programmers must use several VIS instructions to accomplish an operation that can be done with only one

or SSE instruction, but it should be kept in mind that fewer instructions do not automatically result in better performance.

Functionality

VIS re-uses existing SPARC V9 64-bit floating point registers to hold multiple 8, 16, or 32-bit integer values. In this respect, VIS is more similar to the design of

than other SIMD architectures such as SSE/

/ AltiVec. VIS includes a number of operations primarily for graphics support, so most of them are only for integers. These include 3D to 2D conversion, edge processing and pixel distance. There are four ways to use VIS in code: *The GCC - option *Use inline assembly *Use inline template in VSDK, similar to

compiler intrinsics In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs th ...

, which have C function like interfaces *Use the

mediaLib mediaLib (from "multimedia library") is a portable low level library for accelerating multimedia applications, with interfaces in C. It was developed by Sun Microsystems and open-sourced under the CDDL license as part of the OpenSolaris project. ...

multimedia library, which has C function interfaces. It uses VIS on SPARC platforms (and MMX/SSE/SSE2 on x86/x64 platforms) to accelerate multimedia application execution

References

* Gwennap, Linley (5 December 1995). "UltraSparc Adds Multimedia Instructions". '' Microprocessor Report''. * Tremblay, Marc et al. (August 1996). "VIS Speeds New Media Processing". ''

IEEE Micro ''IEEE Micro'' is a peer-reviewed scientific journal published by the IEEE Computer Society covering small systems and semiconductor chips, including integrated circuit processes and practices, project management, development tools and infrastruc ...

''.

External links

An introduction to SPARC’s SIMD offerings (small tutorial)

{{Multimedia extensions SIMD computing Sun Microsystems hardware SPARC microprocessor architecture