Re: [RFA] mips_push_arguments: N32/N64 struct arguments

[Michael Snyder <msnyder at redhat dot com>]

Kevin Buettner wrote:
> 
> The patch below addresses some details in how N32 and N64 struct and
> union arguments are passed.  When using the SGI compiler, I'm seeing
> the following failures fixed with this patch:
> 
> FAIL: gdb.base/call-ar-st.exp: print sum_array_print(10, *list1, *list2, *list3, *list4)
> FAIL: gdb.base/call-ar-st.exp: print print_long_arg_list, pattern 12
> 
> For N32, this patch depends upon my previous patch:
> 
>     [RFA] mips-tdep.c: Set mips_default_saved_regsize to 8 for N32
> 
> Okay to commit?

Kevin, 

I had already arrived at these same changes myself, but then
I seemed to have found that the REG_STRUCT_HAS_ADDR patch which
I just submitted rendered them unnecessary.

Could you try that patch, and meanwhile tell me which fails
these patches helped fix for you?

Michael



> 
>         * mips-tdep.c (mips_push_arguments): For N32 and N64 ABIs, don't
>         write odd sized struct arguments living in registers to the stack.
>         For small struct and union arguments not living in registers,
>         don't shift the struct when writing to the stack.
> 
> Index: mips-tdep.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/mips-tdep.c,v
> retrieving revision 1.85
> diff -u -p -r1.85 mips-tdep.c
> --- mips-tdep.c 31 Jul 2002 20:26:49 -0000      1.85
> +++ mips-tdep.c 31 Jul 2002 23:07:27 -0000
> @@ -2536,7 +2536,9 @@ mips_push_arguments (int nargs,
> 
>               /* Write this portion of the argument to the stack.  */
>               if (argreg > MIPS_LAST_ARG_REGNUM
> -                 || odd_sized_struct
> +                 || (odd_sized_struct
> +                     && tdep->mips_abi != MIPS_ABI_N32
> +                     && tdep->mips_abi != MIPS_ABI_N64)
>                   || fp_register_arg_p (typecode, arg_type))
>                 {
>                   /* Should shorter than int integer values be
> @@ -2552,8 +2554,10 @@ mips_push_arguments (int nargs,
>                            typecode == TYPE_CODE_FLT) && len <= 4)
>                         longword_offset = MIPS_STACK_ARGSIZE - len;
>                       else if ((typecode == TYPE_CODE_STRUCT ||
> -                               typecode == TYPE_CODE_UNION) &&
> -                              TYPE_LENGTH (arg_type) < MIPS_STACK_ARGSIZE)
> +                               typecode == TYPE_CODE_UNION)
> +                              && TYPE_LENGTH (arg_type) < MIPS_STACK_ARGSIZE
> +                              && tdep->mips_abi != MIPS_ABI_N32
> +                              && tdep->mips_abi != MIPS_ABI_N64)
>                         longword_offset = MIPS_STACK_ARGSIZE - len;
>                     }
>