Re: gcc-2.95pre: Internal compiler error in `gen_add2_insn'

[Franz Sirl <Franz dot Sirl-kernel at lauterbach dot com>]

At 11:12 26.05.99 , Jeffrey A Law wrote:

>   In message <99052502052800.01200@ns1102.munich.netsurf.de>you write:
>   >
>   > --Boundary-=_nWlrBbmQBhCDarzOwKkYHIDdqSCD
>   > Content-Type: text/plain
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>   >
>   > Am Tue, 25 May 1999 schrieb Franz Sirl:
>   > >If not, a simple fix would be to replace the test (REGNO (op1) >=
>   > >FIRST_PSEUDO_REGISTER) with (REGNO_REG_CLASS (REGNO (op1)) != 
> GENERAL_REGS
>   > ).
>   > >But probably the solution is different, as the code already tries to 
> swap
>   > op0
>   > >and op1 lateron. Maybe a gen_rtx_PLUS() should be used for 
> constraints che
>   > cking
>   > >instead of the gen_add2_insn(), which can abort?
>   >
>   >
>   > How about this patch? It fixes the testcase, but I haven't run a full
>   > bootstrap yet.
>   >
>   > Franz.
>   >
>   >     * reload1.c (gen_reload): use gen_rtx_SET/PLUS, not gen_add2_insn
>This doesn't seem right.
>
>Why did gen_add2_insn abort?  It should never abort, if it does, then 
>something
>is wrong elsewhere.  That's what you need to debug.  Just changing the code
>to set gen_rtx_SET is papering over the real problem.

Ok, I will debug it. Could you just explain to me in some words what the if 
code in gen_add2_insn is checking for?

rtx
gen_add2_insn (x, y)
      rtx x, y;
{
   int icode = (int) add_optab->handlers[(int) GET_MODE (x)].insn_code;

   if (! (*insn_operand_predicate[icode][0]) (x, insn_operand_mode[icode][0])
       || ! (*insn_operand_predicate[icode][1]) (x, 
insn_operand_mode[icode][1])
       || ! (*insn_operand_predicate[icode][2]) (y, 
insn_operand_mode[icode][2]))
     abort ();

   return (GEN_FCN (icode) (x, x, y));
}

I thought it was doing some constraints checking and as rx = ry + ctr is 
not a valid instruction on PPC it would abort.

Thanks for looking into it,
Franz.