func buildUnaryOpExpr(b *builder, expr *ast.OpExpr) *ref {
op := expr.Op.Lit
B := b.buildExpr(expr.B)
if B == nil {
return nil
}
opPos := expr.Op.Pos
if !B.IsSingle() {
b.Errorf(opPos, "%q on expression list", op)
return nil
}
btyp := B.Type()
if types.IsBasic(btyp, types.Int) {
switch op {
case "+", "-", "^":
ret := b.newTemp(types.Int)
b.b.Arith(ret.IR(), nil, op, B.IR())
return ret
default:
b.Errorf(opPos, "%q on int", op)
return nil
}
} else if types.IsBasic(btyp, types.Bool) {
switch op {
case "!":
ret := b.newTemp(types.Bool)
b.b.Arith(ret.IR(), nil, op, B.IR())
return ret
default:
b.Errorf(opPos, "%q on boolean", op)
return nil
}
}
b.Errorf(opPos, "invalid unary operator %q", op)
return nil
}
func (r *ref) IsBool() bool {
if !r.IsSingle() {
return false
}
return types.IsBasic(r.Type(), types.Bool)
}