YSC4230 Lecture 2 x86Lite

Tradeoffs - more cmds easier to specialize and optimize, less cmds easier to understand and use

X86Lite ~ 20 instructions

Writing to register is better than writing to memory.

Stores results of last executed operation: OF integer overflow, SF, was last result positive or negative? ZF, zero or not

inst

mov instruction

movq SRC, DEST # copy SRC into DEST

movq $4, %rax   // move 64-bit imm into rax
movq %rbx, %rax // move contents of rbx into rax

operands

imm 64-bit integer lbl machine addr reg 16-reg %rax Ind indirect machine address

TODO calling convention for x86Lite