On Wed, Aug 7, 2019 at 7:34 PM Segher Boessenkool <seg...@kernel.crashing.org> wrote: > > On Wed, Aug 07, 2019 at 12:15:29PM -0400, Arvind Sankar wrote: > > I would also like to get some comments on the following idea to make the > > code checks more readable: I am thinking of adding > > bool rtx_def::is_a (enum rtx_code) const > > This would allow us to make all the rtx_code comparisons more readable > > without having to define individual macros for each. > > i.e., > > REG_P (x) => x->is_a (REG) > > GET_CODE (x) == PLUS => x->is_a (PLUS) > > GET_CODE (PATTERN (x)) == SEQUENCE => PATTERN (x)->is_a (SEQUENCE) > > That makes things much worse. Not only is it less readable (IMO), but > the "is_a" idiom is used to check if something is of a certain class, > which is not the case here. > > In "GET_CODE (x) == PLUS" it is clear that what the resulting machine > code does is cheap. With "x->is_a (PLUS)", who knows what is happening > below the covers! > > (And "REG_P" and similar are much shorter code to type).
Note also that in other places in GCC we use is_a <REG> (x) instead, see is-a.h. I don't welcome your member-function style style :/ Richard. > > Segher
