Streaming SIMD Extensions
In computing, Streaming SIMD Extensions (SSE) is a single instruction, multiple data (SIMD) instruction set extension to the x86 architecture, designed by Intel and introduced in 1999. The introduction of SSE was closely tied to the release of the Pentium III series of central processing units (CPUs).
Background
SSE was developed as a response to Advanced Micro Devices (AMD) and their earlier introduction of the 3DNow! technology. Prior to the release of SSE, Intel's flagship product line was the Pentium II. During development, SSE went through several name changes, originally dubbed Katmai New Instructions (KNI) after the code name for the first Pentium III core revision. It was momentarily branded as Internet Streaming SIMD Extensions (ISSE) before settling on the name SSE.
Instruction Set and Features
The introduction of SSE brought forth a set of new instructions aimed at improving the performance of multimedia and floating-point-intensive applications. Here are some key features and iterations of SSE:
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SSE2: Introduced with the Pentium 4, SSE2 expanded the original SSE instruction set and allowed the processing of double-precision floating-point data.
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SSE3 and SSSE3: These subsequent versions introduced further enhancements, particularly in the handling of horizontal operations and improved support for more complex arithmetic operations. SSSE3, or Supplemental SSE3, was a more refined iteration of the SSE technology.
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SSE4: Among many improvements, SSE4 added instructions to enhance text processing and video encoding/decoding, reflecting the growing demand for multimedia applications.
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SSE5: Although proposed by AMD, SSE5 was significant in the ongoing development of SIMD technologies and contributed to the evolution of later instruction sets such as Advanced Vector Extensions (AVX).
Impact on Computing
SSE's impact on computing has been profound, significantly improving the performance of software in domains such as scientific computation, multimedia processing, and gaming. With each iteration, these extensions have provided developers with powerful tools to optimize their applications by leveraging parallel data processing capabilities.
Throughout its various stages, SSE has been a cornerstone in the evolution of SIMD instruction sets and has influenced similar technologies across different processor architectures. Its deployment in both consumer-grade and enterprise-level processors underscores its importance in the landscape of modern computing.