Re: [RFA] mips eabi, passing corner-case structs

[Mark Kettenis <mark.kettenis@xs4all.nl>]

> Date: Wed, 31 May 2006 16:46:51 -0700
> From: Michael Snyder <msnyder@redhat.com>
> 
> That odd little corner case in eabi, wherein structs whose
> single field is a float or double are passed like a float or double.

Is the MIPS eabi documented somewhere?  Or are you just implementing
whatever the GCC du jour emits?  Doesn't your fix also affect structs
that have a single "long long" field?

> 2006-05-31  Michael Snyder  <msnyder@redhat.com>
> 
> 	* mips-tdep.c (mips_eabi_push_dummy_call): Catch corner case, 
> 	structs with a single field of floating point type.
> 
> Index: mips-tdep.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/mips-tdep.c,v
> retrieving revision 1.393
> diff -p -r1.393 mips-tdep.c
> *** mips-tdep.c	31 May 2006 23:15:50 -0000	1.393
> --- mips-tdep.c	31 May 2006 23:44:31 -0000
> *************** mips_eabi_push_dummy_call (struct gdbarc
> *** 2453,2460 ****
>   
>         /* The EABI passes structures that do not fit in a register by
>            reference.  */
> !       if (len > mips_abi_regsize (gdbarch)
> ! 	  && (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION))
>   	{
>   	  store_unsigned_integer (valbuf, mips_abi_regsize (gdbarch),
>   				  VALUE_ADDRESS (arg));
> --- 2453,2467 ----
>   
>         /* The EABI passes structures that do not fit in a register by
>            reference.  */
> !       /* MVS: unles the struct has only one field, and that field
> ! 	 will fit into two registers.  */
> !       if ((typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION)
> ! 	  && TYPE_NFIELDS (arg_type) == 1
> ! 	  && len == 2 * mips_abi_regsize (gdbarch))
> ! 	val = value_contents (arg);
> !       else if (len > mips_abi_regsize (gdbarch)
> ! 	       && (typecode == TYPE_CODE_STRUCT 
> ! 		   || typecode == TYPE_CODE_UNION))
>   	{
>   	  store_unsigned_integer (valbuf, mips_abi_regsize (gdbarch),
>   				  VALUE_ADDRESS (arg));
> 
> --------------090500030309010101070908--
>