Earlier quoted context omitted.
Agreed. AMD didn't throw enough away when they moved X86 to 64bits. They also didn't add enough registers. Variable length CISC is fine. They should steal the bit manipulation instructions from ARMv8 and the vector extensions from RISC-V. They won't.
I think they did a fine job considering all the constraints. The ISA was created in 1999, but the first widely used 64-bit OS (vista) didn't release until 7 years later. In truth, I doubt 64-bit systems became more than half of all systems until a couple years after the release of Window 7 in 2009 (a full decade later). Every transistor used for x86_64 that couldn't also be used for x86 was a competitive liability (i…
They being AMD. The counterargument being that if AMD had been too aggressive, Intel could have done something more conservative. However, then there's the cross licensing agreement ... Arggh.