go/src/cmd/internal/obj/pass.go

// brloop returns the ultimate destination of the series of unconditional jumps beginning at p.
// In the case of an infinite loop, brloop returns nil.
func brloop(p *Prog) *Prog { … }

// checkaddr checks that a has an expected encoding, especially TYPE_CONST vs TYPE_ADDR.
func checkaddr(ctxt *Link, p *Prog, a *Addr) { … }

func linkpatch(ctxt *Link, sym *LSym, newprog ProgAlloc) { … }