} else if ft.Size() == 16 && tt.Size() == 8 {
			op = ssa.OpCvt64Fto32F
		} else {
			s.Fatalf("weird complex conversion %v -> %v", ft, tt)
		}
		ftp := types.FloatForComplex(ft)
		ttp := types.FloatForComplex(tt)
		return s.newValue2(ssa.OpComplexMake, tt,
			s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexReal, ftp, v)),
			s.newValueOrSfCall1(op, ttp, s.newValue1(ssa.OpComplexImag, ftp, v)))
	}

	// Check types.
	if IsSimple[t.Kind()] {
		return t
	}
	switch t.Kind() {
	case TARRAY, TCHAN, TFUNC, TMAP, TSLICE, TSTRING, TSTRUCT:
		return t
	}
	return nil
}

func FloatForComplex(t *Type) *Type {
	switch t.Kind() {
	case TCOMPLEX64:
		return Types[TFLOAT32]
	case TCOMPLEX128:
		return Types[TFLOAT64]
	}
	base.Fatalf("unexpected type: %v", t)
	return nil
}