Re: [PATCH] internal-fn, tree-cfg, v2: Fix .TRAP handling and another __builtin_trap vops issue [PR106099]

[Richard Biener <rguenther@suse.de>]

On Thu, 25 Aug 2022, Jakub Jelinek wrote:

> On Wed, Aug 24, 2022 at 10:20:45AM +0000, Richard Biener wrote:
> > So
> > 
> >    combined_fn cfn = builtin_cfn_unreachable ();
> >    gimple_build (&gsi, false, GSI_NEW_STMT, cfn, void_type_node);
> > 
> > ?
> 
> So what about just using existing call that creates the GIMPLE call,
> whether it is builtin call or internal call?
> I didn't use that initially because the code then wants to add a cgraph
> edge for the fndecl, but in fact it is quite easy to gimple_call_fndecl
> afterwards:

That works for me.

OK,

Thanks,
Richard.

> 2022-08-25  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR tree-optimization/106099
> 	* internal-fn.def (TRAP): Add ECF_LOOPING_CONST_OR_PURE flag.
> 	* tree-cfg.cc (execute_fixup_cfg): Add IFN_TRAP instead of
> 	__builtin_trap to avoid the need of vops.
> 
> 	* gcc.dg/pr106099.c: New test.
> 
> --- gcc/internal-fn.def.jj	2022-07-28 12:43:12.876295553 +0200
> +++ gcc/internal-fn.def	2022-08-23 14:21:49.559364691 +0200
> @@ -458,7 +458,8 @@ DEF_INTERNAL_FN (SPACESHIP, ECF_CONST |
>  
>  /* __builtin_trap created from/for __builtin_unreachable.  */
>  DEF_INTERNAL_FN (TRAP, ECF_CONST | ECF_LEAF | ECF_NORETURN
> -		       | ECF_NOTHROW | ECF_COLD, NULL)
> +		       | ECF_NOTHROW | ECF_COLD | ECF_LOOPING_CONST_OR_PURE,
> +		 NULL)
>  
>  #undef DEF_INTERNAL_INT_FN
>  #undef DEF_INTERNAL_FLT_FN
> --- gcc/tree-cfg.cc.jj	2022-07-26 10:32:23.998267698 +0200
> +++ gcc/tree-cfg.cc	2022-08-25 09:42:19.013039869 +0200
> @@ -9878,16 +9878,16 @@ execute_fixup_cfg (void)
>  	    {
>  	      if (stmt && is_gimple_call (stmt))
>  		gimple_call_set_ctrl_altering (stmt, false);
> -	      tree fndecl = builtin_decl_unreachable ();
> -	      stmt = gimple_build_call (fndecl, 0);
> +	      stmt = gimple_build_builtin_unreachable (UNKNOWN_LOCATION);
>  	      gimple_stmt_iterator gsi = gsi_last_bb (bb);
>  	      gsi_insert_after (&gsi, stmt, GSI_NEW_STMT);
>  	      if (!cfun->after_inlining)
> -		{
> -		  gcall *call_stmt = dyn_cast <gcall *> (stmt);
> -		  node->create_edge (cgraph_node::get_create (fndecl),
> -				     call_stmt, bb->count);
> -		}
> +		if (tree fndecl = gimple_call_fndecl (stmt))
> +		  {
> +		    gcall *call_stmt = dyn_cast <gcall *> (stmt);
> +		    node->create_edge (cgraph_node::get_create (fndecl),
> +				       call_stmt, bb->count);
> +		  }
>  	    }
>  	}
>      }
> --- gcc/testsuite/gcc.dg/pr106099.c.jj	2022-08-23 14:30:51.992057144 +0200
> +++ gcc/testsuite/gcc.dg/pr106099.c	2022-08-23 14:29:04.271508337 +0200
> @@ -0,0 +1,10 @@
> +/* PR tree-optimization/106099 */
> +/* { dg-do compile } */
> +/* { dg-options "-O -fharden-compares -fno-tree-forwprop -fno-tree-ch -fno-tree-dominator-opts -fno-tree-ccp -funreachable-traps --param=scev-max-expr-size=1" } */
> +
> +void
> +foo (void)
> +{
> +  for (unsigned i = 0; i == 0; i++)
> +    __builtin_printf ("%d", i);
> +}
> 
> 	Jakub
> 
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
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