Re: [RFA] rs6000-tdep.c: initial support for e500

[Kevin Buettner <kevinb@redhat.com>]

On Aug 20,  4:16pm, Elena Zannoni wrote:

> This patch adds the initial machinery for supporting the Motorola e500
> processor.
> 
> I added registers and pseudo registers in this patch.
> I will follow up with abi changes soon.
> 
> The e500 processor has vector registers which are 64 bit long.  The
> lower 32 bits of such registers are the same as the general registers
> (hence the pseudos).  No floating point registers in this processor.
> 
> Elena
> 
> 2002-08-19  Elena Zannoni  <ezannoni@redhat.com>
> 
> 	* ppc-tdep.h (struct gdbarch_tdep): Add ev registers.
> 
> 	* rs6000-tdep.c (rs6000_register_virtual_type): Return 64 bit
> 	vector type for ev registers.
> 	(e500_pseudo_register_read): New function.
> 	(e500_pseudo_register_write): New function.
> 	(e500_dwarf2_reg_to_regnum): New function.
> 	(PPC_UISA_NOFP_SPRS): New macro.
> 	(PPC_EV_REGS): New macro.
> 	(PPC_GPRS_PSEUDO_REGS): New macro.
> 	(registers_e500): New register set for e500.
> 	(variants): Add e500 variant.
> 	(rs6000_gdbarch_init): Move setting of pc, sp, fp regnums to
> 	before setting architectural dependent variations.  Initialize ev
> 	registers numbers.  Add case for e500 architecture.  Set the
> 	number of pseudo registers.

Okay.

The fact that the register numbers are so wildly different from any
existing PPC port bothers me a bit, but I'll get over it.  (Actually,
the fact that they can vary as they did is a pretty good indicator
that we've gotten things right elsewhere.  I wonder though if there
might not be a few places which still assume that gpr0 is 0 and gpr31
is 31.  Hmm... yes, rs6000-nat.c has some code like this.)

If I understand things correctly, the pseudo register numbers aren't
set in stone, right?  E.g, if there should come a day when we discover
that some other register ought to be added, we could add it between the
existing "real" registers and the pseudos, right?

Before checking your patch in, take a look at the comments you added and
make sure you have two spaces after each period.  Also make sure that
comments which contain sentences have periods at the ends.

Kevin