[PATCH] Fix ICE in gimple-ssa-warn-alloca.c (PR tree-optimization/79972)

[Richard Biener]

On Thu, 9 Mar 2017, Jakub Jelinek wrote:

> Hi!
> 
> get_range_info must be only called on SSA_NAMEs (that don't have
> POINTER_TYPE_P type), but the first instance of this pass is before
> into ssa so we can see VAR_DECLs in some cases instead of SSA_NAMEs.
> There is on the other side no point testing that range_type is non-zero
> (== not VR_UNDEFINED), inside of the if we test solely for VR_RANGE
> and VR_ANTI_RANGE.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

Ok.

Thanks,
Richard.

> 2017-03-09  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR tree-optimization/79972
> 	* gimple-ssa-warn-alloca.c (alloca_call_type): Only call
> 	get_range_info on SSA_NAMEs.  Formatting fixes.
> 
> 	* gcc.dg/pr79972.c: New test.
> 
> --- gcc/gimple-ssa-warn-alloca.c.jj	2017-03-07 20:04:52.000000000 +0100
> +++ gcc/gimple-ssa-warn-alloca.c	2017-03-09 12:11:41.943934314 +0100
> @@ -300,8 +300,9 @@ alloca_call_type (gimple *stmt, bool is_
>        ret = alloca_type_and_limit (ALLOCA_OK);
>      }
>    // Check the range info if available.
> -  else if (value_range_type range_type = get_range_info (len, &min, &max))
> +  else if (TREE_CODE (len) == SSA_NAME)
>      {
> +      value_range_type range_type = get_range_info (len, &min, &max);
>        if (range_type == VR_RANGE)
>  	{
>  	  if (wi::leu_p (max, max_size))
> @@ -328,7 +329,6 @@ alloca_call_type (gimple *stmt, bool is_
>  	      gimple *def = SSA_NAME_DEF_STMT (len);
>  	      if (gimple_assign_cast_p (def)
>  		  && TYPE_UNSIGNED (TREE_TYPE (gimple_assign_rhs1 (def))))
> -
>  		{
>  		  len_casted = gimple_assign_rhs1 (def);
>  		  range_type = get_range_info (len_casted, &min, &max);
> @@ -344,8 +344,7 @@ alloca_call_type (gimple *stmt, bool is_
>  	      else if (range_type == VR_ANTI_RANGE)
>  		return alloca_type_and_limit (ALLOCA_UNBOUNDED);
>  	      else if (range_type != VR_VARYING)
> -		return
> -		  alloca_type_and_limit (ALLOCA_BOUND_MAYBE_LARGE, max);
> +		return alloca_type_and_limit (ALLOCA_BOUND_MAYBE_LARGE, max);
>  	    }
>  	}
>        else if (range_type == VR_ANTI_RANGE)
> --- gcc/testsuite/gcc.dg/pr79972.c.jj	2017-03-09 12:14:24.188800592 +0100
> +++ gcc/testsuite/gcc.dg/pr79972.c	2017-03-09 12:13:38.000000000 +0100
> @@ -0,0 +1,16 @@
> +/* PR tree-optimization/79972 */
> +/* { dg-do compile } */
> +/* { dg-require-effective-target alloca } */
> +/* { dg-options "-Walloca -Wvla-larger-than=10000" } */
> +
> +int
> +f (int dim, int *b, int *c)
> +{
> +  int newcentroid[3][dim];	/* { dg-warning "unbounded use of variable-length array" } */
> +  int *a = newcentroid[2];
> +  int i, dist = 0;
> +  __builtin_memcpy (newcentroid, c, sizeof (newcentroid));
> +  for (i = 0; i < dim; i++)
> +    dist += (a[i] - b[i]) * (a[i] - b[i]);
> +  return dist;
> +}
> 
> 	Jakub
> 
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)