Re: sparc64 changes and generic backend patches

[Jeffrey A Law <law@cygnus.com>]

  In message < 19980503145648.58820@dot.cygnus.com >you write:
  > (1) Attachment 1 rewrites emit_group_load/store to handle all of the
  >     nifty structure size and alignment problems that do not affect the
  >     IRIX6 n64 ABI.  The canonical problem struct is
  > 
  > 	struct foo { char x[7]; };
  > 
  >     which might live at page_boundary-7.  The old code would produce
  >     either an unaligned trap or a segmentation fault trying to load
  >     these bits into the single outgoing 64-bit register.
I'd kind of prefer Jim Wilson and David Edelsohn review this and
test it a little.  Jim understands the irix issues and probably
understands the code.  David understands the structure passing
problems for AIX, I don't know if he understands the group load
code.

We've made several attempts to fix these structure passing problems
over the years, many of them we've found out later were incorrect.


  > (2) Attachment 2 disables a check in reload not applicable to Sparc's
  >     32-bit FP regs when considered with a 64-bit word size.
Ouch.  I thought Joern has some concerns about this patch, have you
addressed any of them?


  > (3) Attachment 3 contains a few unidentified fixes I found in my tree.
  >     Most of it consists of propogating a change made by Jeff
  > 
  >     Wed Dec 31 01:28:37 1997  Jeff Law  <law@cygnus.com>
  > 
  > 	* expr.c (expand_expr): For {BITFIELD,COMPONENT,ARRAY}_REF, if the
  > 	offset's mode is not ptr_mode, convert it.
I *vaguely* remember this change.  Wow. I can't remember if I was
trying to solve an Alpha/VMS or some weird mn10200 problem.

These changes look reasonable to me.


jeff