patch: morpho ms1-elf support

[DJ Delorie]

> You probably agree, so this is probably not what you mean.

Right, I was mostly concerned about codifying "all functions must have
comments" when what we want is "all functions that should have
comments, have comments".  IMHO the former is detrimental to
maintenance.

I was thinking of stuff like this (which I do a lot):

#define FUNCTION_ARG_REGNO_P(r) m32c_function_arg_regno_p (r)

Or this, which is self-explanatory (given the target's constraint
documentation):

int
m32c_extra_memory_constraint (char c, const char *str ATTRIBUTE_UNUSED)
{
  return c == 'S';
}

But I do include comments like these:


/* The frame looks like this:

   ap -> +------------------------------
         | Return address (3 or 4 bytes)
	 | Saved FB (2 or 4 bytes)
   fb -> +------------------------------
	 | local vars
         | register saves fb
	 |        through r0 as needed
   sp -> +------------------------------
*/

or:

  /* Wide references to memory will be split after reload, so we must
     ensure that all parts of such splits remain legitimate
     addresses.  */
  mode_adjust = GET_MODE_SIZE (mode) - 1;