SSE4.2

SSE4.2

SSE4.2 added STTNI (String and Text New Instructions), several new instructions that perform character searches and comparison on two operands of 16 bytes at a time. These were designed (among other things) to speed up the parsing of XML documents. It also added a CRC32 instruction to compute cyclic redundancy checks as used in certain data transfer protocols. These instructions were first implemented in the Nehalem-based Intel Core i7 product line, and complete the SSE4 instruction set. AMD on the other hand first added support starting with the Bulldozer microarchitecture. Microsoft's Windows 7 was the first operating system to implement SSE4.2, as support is indicated via the CPUID.01H:ECX.SSE42[Bit 20] flag.