Computer Architecture, Instruction Set, Intel, X86, Computer Science.
extension as mentioned in the opcode section. R/M field – 3 bits long. Along with 2 R/M bits, the 5 bits specify an operand, either a register or a memory. In some cases of the ModR/M, we need an additional SIB byte. It is much similar to the ModR/M byte in terms of functionality. For the sake of