Why x86 is unfathomably bloated

Wouldn’t it be interesting to count the percentage of the x86 ISA that a program uses? Well, first of all, we need to define what the term “instruction” even means when it comes to the behemoth that is x86. For a detailed explanation, I highly recommend reading Fabian “ryg” Giesen’s article. 1 In this post, I’ll follow XED’s 2 definition of an instruction, which is: “Intel® XED classifies instructions as iclasses (ADD, SUB, MUL, etc.) of type xed_iclass_enum_t”. 3 All of these “iclasses” are defined inside xed-iclass-enum.

• #interesting
• #rsquo