CSC258H1 Lecture Notes - Bitwise Operation, Subroutine, Assembly Language
Document Summary
Control flow in assembly: shift instructions. 2nd character: l or r = shift direction. 3rd character: a or l = arthematic or logical. Shift left logical == shift left arthematic (not in use) 4th (optional) character: v = a variable number of bits, specified by . 000100 , , = << sra. 000111 , , = >> srl. 000110 , , = >>> . Data movement instructions: these instructions for operating on the hi and lo registers. = lo hi = lo = . Alu instructions: note that for alu instructions, most are r-type instructions. The six-digit codes in the table are therefore the function codes (opcodes are 000000) Exceptions are the i-type instructions (addi, andi, orri, etc. : note all r-type instructions have an i-type equivalent. Risc architecures dictate that an operation doesn"t need an instruction if it can be performed through multiple existing operations.