Why are there only four registers in the most common CPU (x86)? Wouldn’t there be a huge increase in speed if more registers were added? When will more registers be added?
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Why are there only four registers in the most common CPU (x86)? Wouldn’t there be a huge increase in speed if more registers were added? When will more registers be added?
There are more than 4 nowadays. If you look at the history of the x86 architecture, you see that it has evolved from the 8086 instruction set. Intel has always wanted to keep some degree of backwards compatibility in its processor line, so all subsequent processors simply extended the original A,B,C,D registers to wider numbers of bits. The original segment registers can be used for general purposes today, since there aren’t really segments anymore (this is an oversimplification, but roughly true). The new x64 architecture provides some extra registers as well.