Re: reload-branch created

[Bernd Schmidt <bernds_cb1 at t-online dot de>]

Ulrich Weigand wrote:

> - As mentioned in http://gcc.gnu.org/ml/gcc/2005-01/msg00911.html
>   there is a code path in find_reloads that sets rld[].inc to a
>   nonzero value even for a platform that doesn't actually *have*
>   pre-/post-increment insns, leading to an ICE later on.

> Index: gcc/reload.c
> ===================================================================
> RCS file: /cvs/gcc/gcc/gcc/reload.c,v
> retrieving revision 1.268.6.1
> diff -c -p -r1.268.6.1 reload.c
> *** gcc/reload.c	18 Mar 2005 18:40:32 -0000	1.268.6.1
> --- gcc/reload.c	18 Mar 2005 21:43:47 -0000
> *************** find_reloads (struct insn_chain *chain, 
> *** 3215,3222 ****
>   			     MODE_BASE_REG_CLASS (VOIDmode),
>   			     GET_MODE (XEXP (recog_data.operand[i], 0)),
>   			     VOIDmode, 0, 0, i, RELOAD_FOR_NONE);
> ! 	    rld[operand_reloadnum[i]].inc
> ! 	      = GET_MODE_SIZE (GET_MODE (recog_data.operand[i]));
>   	  }
>   	else if (goal_alternative_matched[i] == -1)
>   	  {
> --- 3215,3224 ----
>   			     MODE_BASE_REG_CLASS (VOIDmode),
>   			     GET_MODE (XEXP (recog_data.operand[i], 0)),
>   			     VOIDmode, 0, 0, i, RELOAD_FOR_NONE);
> ! 
> ! 	    if (rld[operand_reloadnum[i]].inc)
> ! 	      rld[operand_reloadnum[i]].inc
> ! 	        = GET_MODE_SIZE (GET_MODE (recog_data.operand[i]));
>   	  }
>   	else if (goal_alternative_matched[i] == -1)
>   	  {

This is wrong.  inc is unconditionally cleared in push_reload, so it 
can't be nonzero here.

I did a bit of research into how autoinc is currently dealt with by 
reload.  The obscure "out && ! out_reg" test is used at the last stage, 
but this condition is set up a bit earlier in choose_reload_regs with a 
much more sensible test for PRE_DEC codes etc.

I guess the best solution is to change the place you modified, but to 
use a test that checks for autoinc codes.  I'll come up with something.


Bernd