should check src/dest, if src and dst is the same, it doesnt kill
anything)

immiediate number. Richards benchmark runs.

as scale in memory op

find symbols

(inlining a function will copy ssa vars from the function, and they may
already have a use count)

res; op res, y -> res. Instead, I used to generate: op x, y -> x; mov x
-> res

(for easy debugging)

stack pointer before calling, unless we pushed arguments by stack)

assembly)

still restored callee-saved registers, should directly jump to it