Re: SH: use register names instead of numbers

[Joern Rennecke <amylaar at redhat dot com>]

> + /* Called via traverse_md_constants; emit a #define for
> +    the current constant definition.  */
> + static int
> + print_md_constant (slot, info)
> 
> This is missing a blank line.

Between the comment and the return type?
Should gen_insn_name get a blank line at this place then, too?

> +   fprintf (file, "#define %s %s\n", def->name, def->value);
> 
> I would recommend putting a prefix here, like MD_%s.  Otherwise, you
> risk further namespace pollution.  Since the main use is within the MD
> file, the name used in the .h file isn't that critical.

There are a lot of register number definitions in the tm.h files that
would best go into define_constants.  So there is not really an extra
namespace pollutions, since definitions in tm.h are very visible, too.
Exporting the defines without a prefix makes it viable to do these
defines just once.

If you think there is also a good application for names that are less
visible, it is simple to add code to have an optional prefix, i.e.

(define_constants "MD_" [
    (foo 0)
    (bar 1)
])

Would give
#define MD_foo 0
#define MD_bar 1

We could also use the prefix "*" to indicate that no #defines should be
emitted.