v = v.Args[0]
	}
	switch v.Op {
	case OpSP, OpLocalAddr, OpSelectNAddr, OpGetCallerSP:
		return true
	}
	return false
}

// IsGlobalAddr reports whether v is known to be an address of a global (or nil).
func IsGlobalAddr(v *Value) bool {
	for v.Op == OpOffPtr || v.Op == OpAddPtr || v.Op == OpPtrIndex || v.Op == OpCopy {
		v = v.Args[0]
	}
	if v.Op == OpAddr && v.Args[0].Op == OpSB {