Re: [PATCH] Fix ICE caused by calling optimize_function_for_speed_p (NULL) (PR middle-end/37414)

["Richard Guenther" <richard dot guenther at gmail dot com>]

On Mon, Sep 8, 2008 at 9:26 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Mon, Sep 08, 2008 at 09:17:48AM -0400, Jakub Jelinek wrote:
>> This patch fixes ICE on the attached testcase the same way other
>> places in fold-const.c handle it, namely assuming that cfun == NULL
>> implies optimization for speed.  I'm not convinced that is a good idea
>> though, IMHO it would be better if optimize_function_for_s{peed,ize}_p
>> handled NULL argument and just returned {!,}optimize_size in that case.
>> I'm pretty sure one can construct testcases that would ICE e.g. on
>> all 3 optimize_function_for_s*_p calls in builtins.c.
>
> Here is an alternative patch that handles fun == NULL in
> optimize_function_for_{size,speed}_p instead.  Bootstrapped/regtested on
> x86_64-linux, ok for trunk?

Ok.

Thanks,
Richard.

> 2008-09-08  Jakub Jelinek  <jakub@redhat.com>
>
>        PR middle-end/37414
>        * predict.c (optimize_function_for_size_p): Don't segfault if
>        FUN is NULL.
>        * fold-const.c (LOGICAL_OP_NON_SHORT_CIRCUIT, fold_truthop,
>        tree_swap_operands_p): Don't test cfun != NULL before calling
>        optimize_function_for_s*_p.
>
>        * g++.dg/opt/init2.C: New test.
>
> --- gcc/predict.c.jj    2008-09-05 12:56:32.000000000 +0200
> +++ gcc/predict.c       2008-09-08 17:42:25.000000000 +0200
> @@ -203,7 +203,8 @@ bool
>  optimize_function_for_size_p (struct function *fun)
>  {
>   return (optimize_size
> -         || fun->function_frequency == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED);
> +         || (fun && (fun->function_frequency
> +                     == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)));
>  }
>
>  /* Return true when current function should always be optimized for speed.  */
> --- gcc/fold-const.c.jj 2008-09-05 12:56:31.000000000 +0200
> +++ gcc/fold-const.c    2008-09-08 17:43:33.000000000 +0200
> @@ -5110,7 +5110,7 @@ fold_cond_expr_with_comparison (tree typ
>
>  #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
>  #define LOGICAL_OP_NON_SHORT_CIRCUIT \
> -  (BRANCH_COST (!cfun || optimize_function_for_speed_p (cfun), \
> +  (BRANCH_COST (optimize_function_for_speed_p (cfun), \
>                false) >= 2)
>  #endif
>
> @@ -5359,7 +5359,7 @@ fold_truthop (enum tree_code code, tree
>      that can be merged.  Avoid doing this if the RHS is a floating-point
>      comparison since those can trap.  */
>
> -  if (BRANCH_COST (!cfun || optimize_function_for_speed_p (cfun),
> +  if (BRANCH_COST (optimize_function_for_speed_p (cfun),
>                   false) >= 2
>       && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
>       && simple_operand_p (rl_arg)
> @@ -6682,7 +6682,7 @@ tree_swap_operands_p (const_tree arg0, c
>   if (TREE_CONSTANT (arg0))
>     return 1;
>
> -  if (cfun && optimize_function_for_size_p (cfun))
> +  if (optimize_function_for_size_p (cfun))
>     return 0;
>
>   if (reorder && flag_evaluation_order
> --- gcc/testsuite/g++.dg/opt/init2.C.jj 2008-09-08 15:03:28.000000000 +0200
> +++ gcc/testsuite/g++.dg/opt/init2.C    2008-09-08 15:02:04.000000000 +0200
> @@ -0,0 +1,6 @@
> +// PR middle-end/37414
> +// { dg-do compile }
> +// { dg-options "-O2 -ffast-math" }
> +
> +double x = 6.0;
> +double y = x * x;
>
>
>        Jakub
>