// checkaddr checks that a has an expected encoding, especially TYPE_CONST vs TYPE_ADDR.
func checkaddr(ctxt *Link, p *Prog, a *Addr) {
	switch a.Type {
	case TYPE_NONE, TYPE_REGREG2, TYPE_REGLIST:
		return

	case TYPE_BRANCH, TYPE_TEXTSIZE:
		if a.Reg != 0 || a.Index != 0 || a.Scale != 0 || a.Name != 0 {
			break
		}
		return

	case TYPE_MEM:
		return

	case TYPE_CONST:

	// behavior seems inconsistent. It should probably either
	// never check for arch or do it in all cases.

	oclassTestsCommon := []*oclassTest{
		{&obj.Addr{Type: obj.TYPE_NONE}, Ynone},
		{&obj.Addr{Type: obj.TYPE_BRANCH}, Ybr},
		{&obj.Addr{Type: obj.TYPE_TEXTSIZE}, Ytextsize},

		{&obj.Addr{Type: obj.TYPE_INDIR, Name: obj.NAME_EXTERN}, Yindir},
		{&obj.Addr{Type: obj.TYPE_INDIR, Name: obj.NAME_GOTREF}, Yindir},