问题
From Intel's SDM, section 2.2.1 specifies that the REX prefix is used to:
- Specify GPRs and SSE registers.
- Specify 64-bit operand size.
- Specify extended control registers
But what do the letters REX stand for in the acronym?
回答1:
This 2002 Hot Chips presentation by AMD expands the acronym on slide 10: "REX (Register Extension)".
Kevin McGrath and Dave Christie, "The AMD x86-64 Architecture: Extending the x86 to 64 bits", Hot Chips 14, August 2002.
来源：https://stackoverflow.com/questions/59164978/what-does-rex-stand-for-in-an-x86-64-rex-prefix