[4/5] value-range: Add as_string diagnostics helper

  gcc/ChangeLog:

	* value-range.cc (get_bound_with_infinite_markers): New static helper.
	(irange::as_string): New definition.
	* value-range.h: New declaration.

---
Provide means to print a value range to a newly allocated buffer.
The caller is responsible to free() the allocated memory.

Bootstrapped and regtested on x86_86-unknown-linux with no regressions.
Ok for trunk?

Cc: Andrew MacLeod <amacleod@redhat.com>
Cc: Aldy Hernandez <aldyh@redhat.com>
---
 gcc/value-range.cc | 56 ++++++++++++++++++++++++++++++++++++++++++++++
 gcc/value-range.h  |  3 +++
 2 files changed, 59 insertions(+)
  

On Sat, Nov 12, 2022 at 3:47 PM Bernhard Reutner-Fischer via
Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>
> gcc/ChangeLog:
>
>         * value-range.cc (get_bound_with_infinite_markers): New static helper.
>         (irange::as_string): New definition.
>         * value-range.h: New declaration.
>
> ---
> Provide means to print a value range to a newly allocated buffer.
> The caller is responsible to free() the allocated memory.
>
> Bootstrapped and regtested on x86_86-unknown-linux with no regressions.
> Ok for trunk?
>
> Cc: Andrew MacLeod <amacleod@redhat.com>
> Cc: Aldy Hernandez <aldyh@redhat.com>
> ---
>  gcc/value-range.cc | 56 ++++++++++++++++++++++++++++++++++++++++++++++
>  gcc/value-range.h  |  3 +++
>  2 files changed, 59 insertions(+)
>
> diff --git a/gcc/value-range.cc b/gcc/value-range.cc
> index a855aaf626c..51cd9a38d90 100644
> --- a/gcc/value-range.cc
> +++ b/gcc/value-range.cc
> @@ -3099,6 +3099,62 @@ debug (const value_range &vr)
>    fprintf (stderr, "\n");
>  }
>
> +/* Helper for irange::as_string().  Print a bound to an allocated buffer.  */
> +static char *

Can we start using std::string instead of char* here?


> +get_bound_with_infinite_markers (tree bound)
> +{
> +  tree type = TREE_TYPE (bound);
> +  wide_int type_min = wi::min_value (TYPE_PRECISION (type), TYPE_SIGN (type));
> +  wide_int type_max = wi::max_value (TYPE_PRECISION (type), TYPE_SIGN (type));
> +
> +  if (INTEGRAL_TYPE_P (type)
> +      && !TYPE_UNSIGNED (type)
> +      && TREE_CODE (bound) == INTEGER_CST
> +      && wi::to_wide (bound) == type_min
> +      && TYPE_PRECISION (type) != 1)
> +    return xstrdup ("-INF");
> +  else if (TREE_CODE (bound) == INTEGER_CST
> +          && wi::to_wide (bound) == type_max
> +          && TYPE_PRECISION (type) != 1)
> +    return xstrdup ("+INF");
> +  else
> +    return print_generic_expr_to_str (bound);
No reason to do xstrdup any more either.

> +}
> +
> +
> +/* Return an irange as string. Return NULL on failure, an allocated
> +   string on success.  */
> +char *

Likewise.

Thanks,
Andrew Pinski

> +irange::as_string ()
> +{
> +  char *ret = NULL;
This becomes std::string ret;
> +  if (undefined_p() || varying_p () || m_num_ranges == 0)
> +    return ret;
> +
> +  for (unsigned i = 0; i < m_num_ranges; ++i)
> +    {
> +      tree lb = m_base[i * 2];
> +      tree ub = m_base[i * 2 + 1];
> +      /* Construct [lower_bound,upper_bound].  */
> +      char *lbs = get_bound_with_infinite_markers (lb);
> +      char *ubs = get_bound_with_infinite_markers (ub);
> +      /* Paranoia mode */
> +      if (!lbs)
> +       lbs = xstrdup ("");
> +      if (!ubs)
> +       ubs = xstrdup ("");
> +
> +      if (ret)
> +       ret = reconcat (ret, ret, "[", lbs, ",", ubs, "]", NULL);
> +      else
> +       ret = concat ("[", lbs, ",", ubs, "]", NULL);
> +
> +      free (lbs);
> +      free (ubs);
> +    }
> +  return ret;
> +}
> +
>  /* Create two value-ranges in *VR0 and *VR1 from the anti-range *AR
>     so that *VR0 U *VR1 == *AR.  Returns true if that is possible,
>     false otherwise.  If *AR can be represented with a single range
> diff --git a/gcc/value-range.h b/gcc/value-range.h
> index c87734dd8cd..76242e4bf45 100644
> --- a/gcc/value-range.h
> +++ b/gcc/value-range.h
> @@ -160,6 +160,9 @@ public:
>    wide_int get_nonzero_bits () const;
>    void set_nonzero_bits (const wide_int_ref &bits);
>
> +  // For diagnostics.
> +  char *as_string ();
> +
>    // Deprecated legacy public methods.
>    tree min () const;                           // DEPRECATED
>    tree max () const;                           // DEPRECATED
> --
> 2.38.1
>
  

On 11/12/22 16:55, Andrew Pinski via Gcc-patches wrote:
> On Sat, Nov 12, 2022 at 3:47 PM Bernhard Reutner-Fischer via
> Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>> gcc/ChangeLog:
>>
>>          * value-range.cc (get_bound_with_infinite_markers): New static helper.
>>          (irange::as_string): New definition.
>>          * value-range.h: New declaration.
>>
>> ---
>> Provide means to print a value range to a newly allocated buffer.
>> The caller is responsible to free() the allocated memory.
>>
>> Bootstrapped and regtested on x86_86-unknown-linux with no regressions.
>> Ok for trunk?
>>
>> Cc: Andrew MacLeod <amacleod@redhat.com>
>> Cc: Aldy Hernandez <aldyh@redhat.com>
>> ---
>>   gcc/value-range.cc | 56 ++++++++++++++++++++++++++++++++++++++++++++++
>>   gcc/value-range.h  |  3 +++
>>   2 files changed, 59 insertions(+)
>>
>> diff --git a/gcc/value-range.cc b/gcc/value-range.cc
>> index a855aaf626c..51cd9a38d90 100644
>> --- a/gcc/value-range.cc
>> +++ b/gcc/value-range.cc
>> @@ -3099,6 +3099,62 @@ debug (const value_range &vr)
>>     fprintf (stderr, "\n");
>>   }
>>
>> +/* Helper for irange::as_string().  Print a bound to an allocated buffer.  */
>> +static char *
> Can we start using std::string instead of char* here?

If it makes the code easier to read/maintain, sure.  std::string isn't 
used heavily, but has crept into a few places, mostly in target files.  
std::string isn't something we've pushed at all in terms of preferred 
practices.


Jeff