Fix VRP ICE on x >> cst1; if (x cmp cst2) (PR tree-optimization/53058, take 2)

On Tue, Apr 24, 2012 at 10:33:58AM +0200, Richard Guenther wrote:
> > So like this instead?
> 
> Yes!

Unfortunately that didn't bootstrap, apparently double-int.h is included in
gen* which aren't linked with double-int.o, and the inlines stay at -O0
or with -fkeep-inline-functions.  Even guarding with #ifndef GENERATOR_FILE
doesn't work, because gengtype is apparently built both with that and
without.

So this new version instead just prototypes them in double-int.h and defines
in double-int.c.  Still ok?

2012-04-25  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/53058
	* double-int.h (double_int_max_value, double_int_min_value): New
	prototypes.
	* double-int.c (double_int_max_value, double_int_min_value): New
	functions.
	* tree-vrp.c (register_edge_assert_for_2): Compare mask
	for LE_EXPR or GT_EXPR with double_int_max_value
	instead of double_int_mask.

	* gcc.c-torture/compile/pr53058.c: New test.



	Jakub

On Wed, Apr 25, 2012 at 11:21 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Tue, Apr 24, 2012 at 10:33:58AM +0200, Richard Guenther wrote:
>> > So like this instead?
>>
>> Yes!
>
> Unfortunately that didn't bootstrap, apparently double-int.h is included in
> gen* which aren't linked with double-int.o, and the inlines stay at -O0
> or with -fkeep-inline-functions.  Even guarding with #ifndef GENERATOR_FILE
> doesn't work, because gengtype is apparently built both with that and
> without.
>
> So this new version instead just prototypes them in double-int.h and defines
> in double-int.c.  Still ok?

Sure.

> 2012-04-25  Jakub Jelinek  <jakub@redhat.com>
>
>        PR tree-optimization/53058
>        * double-int.h (double_int_max_value, double_int_min_value): New
>        prototypes.
>        * double-int.c (double_int_max_value, double_int_min_value): New
>        functions.
>        * tree-vrp.c (register_edge_assert_for_2): Compare mask
>        for LE_EXPR or GT_EXPR with double_int_max_value
>        instead of double_int_mask.
>
>        * gcc.c-torture/compile/pr53058.c: New test.
>
> --- gcc/double-int.h.jj 2012-03-29 12:01:31.623648408 +0200
> +++ gcc/double-int.h    2012-04-24 17:54:37.798945484 +0200
> @@ -1,5 +1,5 @@
>  /* Operations with long integers.
> -   Copyright (C) 2006, 2007, 2008, 2010 Free Software Foundation, Inc.
> +   Copyright (C) 2006, 2007, 2008, 2010, 2012 Free Software Foundation, Inc.
>
>  This file is part of GCC.
>
> @@ -242,6 +242,9 @@ double_int double_int_sext (double_int,
>  double_int double_int_zext (double_int, unsigned);
>  double_int double_int_mask (unsigned);
>
> +double_int double_int_max_value (unsigned int, bool);
> +double_int double_int_min_value (unsigned int, bool);
> +
>  #define ALL_ONES (~((unsigned HOST_WIDE_INT) 0))
>
>  /* The operands of the following comparison functions must be processed
> --- gcc/double-int.c.jj 2012-04-02 21:40:10.000000000 +0200
> +++ gcc/double-int.c    2012-04-24 17:55:44.745723956 +0200
> @@ -1,5 +1,5 @@
>  /* Operations with long integers.
> -   Copyright (C) 2006, 2007, 2009, 2010 Free Software Foundation, Inc.
> +   Copyright (C) 2006, 2007, 2009, 2010, 2012 Free Software Foundation, Inc.
>
>  This file is part of GCC.
>
> @@ -616,6 +616,26 @@ double_int_mask (unsigned prec)
>   return mask;
>  }
>
> +/* Returns a maximum value for signed or unsigned integer
> +   of precision PREC.  */
> +
> +double_int
> +double_int_max_value (unsigned int prec, bool uns)
> +{
> +  return double_int_mask (prec - (uns ? 0 : 1));
> +}
> +
> +/* Returns a minimum value for signed or unsigned integer
> +   of precision PREC.  */
> +
> +double_int
> +double_int_min_value (unsigned int prec, bool uns)
> +{
> +  if (uns)
> +    return double_int_zero;
> +  return double_int_lshift (double_int_one, prec - 1, prec, false);
> +}
> +
>  /* Clears the bits of CST over the precision PREC.  If UNS is false, the bits
>    outside of the precision are set to the sign bit (i.e., the PREC-th one),
>    otherwise they are set to zero.
> --- gcc/tree-vrp.c.jj   2012-04-24 07:59:58.142773712 +0200
> +++ gcc/tree-vrp.c      2012-04-24 17:41:10.473562899 +0200
> @@ -4565,6 +4565,7 @@ register_edge_assert_for_2 (tree name, e
>              && INTEGRAL_TYPE_P (TREE_TYPE (name2))
>              && IN_RANGE (tree_low_cst (cst2, 1), 1, prec - 1)
>              && prec <= 2 * HOST_BITS_PER_WIDE_INT
> +             && prec == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (val)))
>              && live_on_edge (e, name2)
>              && !has_single_use (name2))
>            {
> @@ -4598,8 +4599,10 @@ register_edge_assert_for_2 (tree name, e
>            new_val = val2;
>          else
>            {
> +             double_int maxval
> +               = double_int_max_value (prec, TYPE_UNSIGNED (TREE_TYPE (val)));
>              mask = double_int_ior (tree_to_double_int (val2), mask);
> -             if (double_int_minus_one_p (double_int_sext (mask, prec)))
> +             if (double_int_equal_p (mask, maxval))
>                new_val = NULL_TREE;
>              else
>                new_val = double_int_to_tree (TREE_TYPE (val2), mask);
> --- gcc/testsuite/gcc.c-torture/compile/pr53058.c.jj    2012-04-24 17:41:10.475662886 +0200
> +++ gcc/testsuite/gcc.c-torture/compile/pr53058.c       2012-04-24 17:41:10.475662886 +0200
> @@ -0,0 +1,12 @@
> +/* PR tree-optimization/53058 */
> +
> +int a, b, c;
> +
> +void
> +foo ()
> +{
> +  c = b >> 16;
> +  if (c > 32767)
> +    c = 0;
> +  a = b;
> +}
>
>
>        Jakub