Re: PR78153

[Rainer Orth]

Hi Prathamesh,

> Thanks, I committed the attached patch as r242786 after
> bootstrap+test on x86_64-unknown-linux-gnu and
> cross-test on arm*-*-*, aarch64*-*-*.

this patch broke Ada bootstrap on Solaris.  I've filed PR middle-end/78501.

Rainer

-- 
-
Rainer Orth, Center for Biotechnology, Bielefeld University

Re: PR78153

[Prathamesh Kulkarni]

On 23 November 2016 at 17:51, Richard Biener <rguent...@suse.de> wrote:
> On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:
>
>> On 23 November 2016 at 17:21, Richard Biener <rguent...@suse.de> wrote:
>> > On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:
>> >
>> >> On 23 November 2016 at 15:16, Richard Biener <rguent...@suse.de> wrote:
>> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >
>> >> >> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
>> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >
>> >> >> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> 
>> >> >> >> wrote:
>> >> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >> >
>> >> >> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> 
>> >> >> >> >> wrote:
>> >> >> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >> >> >
>> >> >> >> >> >> Hi,
>> >> >> >> >> >> As suggested by Martin in PR78153 strlen's return value 
>> >> >> >> >> >> cannot exceed
>> >> >> >> >> >> PTRDIFF_MAX.
>> >> >> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in 
>> >> >> >> >> >> extract_range_basic()
>> >> >> >> >> >> in the attached patch.
>> >> >> >> >> >>
>> >> >> >> >> >> However it regressed strlenopt-3.c:
>> >> >> >> >> >>
>> >> >> >> >> >> Consider fn1() from strlenopt-3.c:
>> >> >> >> >> >>
>> >> >> >> >> >> __attribute__((noinline, noclone)) size_t
>> >> >> >> >> >> fn1 (char *p, char *q)
>> >> >> >> >> >> {
>> >> >> >> >> >>   size_t s = strlen (q);
>> >> >> >> >> >>   strcpy (p, q);
>> >> >> >> >> >>   return s - strlen (p);
>> >> >> >> >> >> }
>> >> >> >> >> >>
>> >> >> >> >> >> The optimized dump shows the following:
>> >> >> >> >> >>
>> >> >> >> >> >> __attribute__((noclone, noinline))
>> >> >> >> >> >> fn1 (char * p, char * q)
>> >> >> >> >> >> {
>> >> >> >> >> >>   size_t s;
>> >> >> >> >> >>   size_t _7;
>> >> >> >> >> >>   long unsigned int _9;
>> >> >> >> >> >>
>> >> >> >> >> >>   :
>> >> >> >> >> >>   s_4 = strlen (q_3(D));
>> >> >> >> >> >>   _9 = s_4 + 1;
>> >> >> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >> >> >> >>   _7 = 0;
>> >> >> >> >> >>   return _7;
>> >> >> >> >> >>
>> >> >> >> >> >> }
>> >> >> >> >> >>
>> >> >> >> >> >> which introduces the regression, because the test expects 
>> >> >> >> >> >> "return 0;" in fn1().
>> >> >> >> >> >>
>> >> >> >> >> >> The issue seems to be in vrp2:
>> >> >> >> >> >>
>> >> >> >> >> >> Before the patch:
>> >> >> >> >> >> Visiting statement:
>> >> >> >> >> >> s_4 = strlen (q_3(D));
>> >> >> >> >> >> Found new range for s_4: VARYING
>> >> >> >> >> >>
>> >> >> >> >> >> Visiting statement:
>> >> >> >> >> >> _1 = s_4;
>> >> >> >> >> >> Found new range for _1: [s_4, s_

Re: PR78153

[Richard Biener]

On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:

> On 23 November 2016 at 17:21, Richard Biener <rguent...@suse.de> wrote:
> > On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:
> >
> >> On 23 November 2016 at 15:16, Richard Biener <rguent...@suse.de> wrote:
> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >
> >> >> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >
> >> >> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> 
> >> >> >> wrote:
> >> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >> >
> >> >> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> 
> >> >> >> >> wrote:
> >> >> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >> >> >
> >> >> >> >> >> Hi,
> >> >> >> >> >> As suggested by Martin in PR78153 strlen's return value cannot 
> >> >> >> >> >> exceed
> >> >> >> >> >> PTRDIFF_MAX.
> >> >> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in 
> >> >> >> >> >> extract_range_basic()
> >> >> >> >> >> in the attached patch.
> >> >> >> >> >>
> >> >> >> >> >> However it regressed strlenopt-3.c:
> >> >> >> >> >>
> >> >> >> >> >> Consider fn1() from strlenopt-3.c:
> >> >> >> >> >>
> >> >> >> >> >> __attribute__((noinline, noclone)) size_t
> >> >> >> >> >> fn1 (char *p, char *q)
> >> >> >> >> >> {
> >> >> >> >> >>   size_t s = strlen (q);
> >> >> >> >> >>   strcpy (p, q);
> >> >> >> >> >>   return s - strlen (p);
> >> >> >> >> >> }
> >> >> >> >> >>
> >> >> >> >> >> The optimized dump shows the following:
> >> >> >> >> >>
> >> >> >> >> >> __attribute__((noclone, noinline))
> >> >> >> >> >> fn1 (char * p, char * q)
> >> >> >> >> >> {
> >> >> >> >> >>   size_t s;
> >> >> >> >> >>   size_t _7;
> >> >> >> >> >>   long unsigned int _9;
> >> >> >> >> >>
> >> >> >> >> >>   :
> >> >> >> >> >>   s_4 = strlen (q_3(D));
> >> >> >> >> >>   _9 = s_4 + 1;
> >> >> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >> >> >> >>   _7 = 0;
> >> >> >> >> >>   return _7;
> >> >> >> >> >>
> >> >> >> >> >> }
> >> >> >> >> >>
> >> >> >> >> >> which introduces the regression, because the test expects 
> >> >> >> >> >> "return 0;" in fn1().
> >> >> >> >> >>
> >> >> >> >> >> The issue seems to be in vrp2:
> >> >> >> >> >>
> >> >> >> >> >> Before the patch:
> >> >> >> >> >> Visiting statement:
> >> >> >> >> >> s_4 = strlen (q_3(D));
> >> >> >> >> >> Found new range for s_4: VARYING
> >> >> >> >> >>
> >> >> >> >> >> Visiting statement:
> >> >> >> >> >> _1 = s_4;
> >> >> >> >> >> Found new range for _1: [s_4, s_4]
> >> >> >> >> >> marking stmt to be not simulated again
> >> >> >> >> >>
> >> >> >> >> >> Visiting statement:
> >> >> >> >> >> _7 = s_4 - _1;
> >> >> >> >> >> Applying pattern match.pd:111, gimple-mat

Re: PR78153

[Prathamesh Kulkarni]

On 23 November 2016 at 17:21, Richard Biener <rguent...@suse.de> wrote:
> On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:
>
>> On 23 November 2016 at 15:16, Richard Biener <rguent...@suse.de> wrote:
>> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >
>> >> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
>> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >
>> >> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
>> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >
>> >> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> 
>> >> >> >> wrote:
>> >> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >> >
>> >> >> >> >> Hi,
>> >> >> >> >> As suggested by Martin in PR78153 strlen's return value cannot 
>> >> >> >> >> exceed
>> >> >> >> >> PTRDIFF_MAX.
>> >> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in 
>> >> >> >> >> extract_range_basic()
>> >> >> >> >> in the attached patch.
>> >> >> >> >>
>> >> >> >> >> However it regressed strlenopt-3.c:
>> >> >> >> >>
>> >> >> >> >> Consider fn1() from strlenopt-3.c:
>> >> >> >> >>
>> >> >> >> >> __attribute__((noinline, noclone)) size_t
>> >> >> >> >> fn1 (char *p, char *q)
>> >> >> >> >> {
>> >> >> >> >>   size_t s = strlen (q);
>> >> >> >> >>   strcpy (p, q);
>> >> >> >> >>   return s - strlen (p);
>> >> >> >> >> }
>> >> >> >> >>
>> >> >> >> >> The optimized dump shows the following:
>> >> >> >> >>
>> >> >> >> >> __attribute__((noclone, noinline))
>> >> >> >> >> fn1 (char * p, char * q)
>> >> >> >> >> {
>> >> >> >> >>   size_t s;
>> >> >> >> >>   size_t _7;
>> >> >> >> >>   long unsigned int _9;
>> >> >> >> >>
>> >> >> >> >>   :
>> >> >> >> >>   s_4 = strlen (q_3(D));
>> >> >> >> >>   _9 = s_4 + 1;
>> >> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >> >> >>   _7 = 0;
>> >> >> >> >>   return _7;
>> >> >> >> >>
>> >> >> >> >> }
>> >> >> >> >>
>> >> >> >> >> which introduces the regression, because the test expects 
>> >> >> >> >> "return 0;" in fn1().
>> >> >> >> >>
>> >> >> >> >> The issue seems to be in vrp2:
>> >> >> >> >>
>> >> >> >> >> Before the patch:
>> >> >> >> >> Visiting statement:
>> >> >> >> >> s_4 = strlen (q_3(D));
>> >> >> >> >> Found new range for s_4: VARYING
>> >> >> >> >>
>> >> >> >> >> Visiting statement:
>> >> >> >> >> _1 = s_4;
>> >> >> >> >> Found new range for _1: [s_4, s_4]
>> >> >> >> >> marking stmt to be not simulated again
>> >> >> >> >>
>> >> >> >> >> Visiting statement:
>> >> >> >> >> _7 = s_4 - _1;
>> >> >> >> >> Applying pattern match.pd:111, gimple-match.c:27997
>> >> >> >> >> Match-and-simplified s_4 - _1 to 0
>> >> >> >> >> Intersecting
>> >> >> >> >>   [0, 0]
>> >> >> >> >> and
>> >> >> >> >>   [0, +INF]
>> >> >> >> >> to
>> >> >> >> >> 

Re: PR78153

[Richard Biener]

On Wed, 23 Nov 2016, Prathamesh Kulkarni wrote:

> On 23 November 2016 at 15:16, Richard Biener <rguent...@suse.de> wrote:
> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >
> >> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >
> >> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
> >> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >
> >> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> 
> >> >> >> wrote:
> >> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >> >
> >> >> >> >> Hi,
> >> >> >> >> As suggested by Martin in PR78153 strlen's return value cannot 
> >> >> >> >> exceed
> >> >> >> >> PTRDIFF_MAX.
> >> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in 
> >> >> >> >> extract_range_basic()
> >> >> >> >> in the attached patch.
> >> >> >> >>
> >> >> >> >> However it regressed strlenopt-3.c:
> >> >> >> >>
> >> >> >> >> Consider fn1() from strlenopt-3.c:
> >> >> >> >>
> >> >> >> >> __attribute__((noinline, noclone)) size_t
> >> >> >> >> fn1 (char *p, char *q)
> >> >> >> >> {
> >> >> >> >>   size_t s = strlen (q);
> >> >> >> >>   strcpy (p, q);
> >> >> >> >>   return s - strlen (p);
> >> >> >> >> }
> >> >> >> >>
> >> >> >> >> The optimized dump shows the following:
> >> >> >> >>
> >> >> >> >> __attribute__((noclone, noinline))
> >> >> >> >> fn1 (char * p, char * q)
> >> >> >> >> {
> >> >> >> >>   size_t s;
> >> >> >> >>   size_t _7;
> >> >> >> >>   long unsigned int _9;
> >> >> >> >>
> >> >> >> >>   :
> >> >> >> >>   s_4 = strlen (q_3(D));
> >> >> >> >>   _9 = s_4 + 1;
> >> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >> >> >>   _7 = 0;
> >> >> >> >>   return _7;
> >> >> >> >>
> >> >> >> >> }
> >> >> >> >>
> >> >> >> >> which introduces the regression, because the test expects "return 
> >> >> >> >> 0;" in fn1().
> >> >> >> >>
> >> >> >> >> The issue seems to be in vrp2:
> >> >> >> >>
> >> >> >> >> Before the patch:
> >> >> >> >> Visiting statement:
> >> >> >> >> s_4 = strlen (q_3(D));
> >> >> >> >> Found new range for s_4: VARYING
> >> >> >> >>
> >> >> >> >> Visiting statement:
> >> >> >> >> _1 = s_4;
> >> >> >> >> Found new range for _1: [s_4, s_4]
> >> >> >> >> marking stmt to be not simulated again
> >> >> >> >>
> >> >> >> >> Visiting statement:
> >> >> >> >> _7 = s_4 - _1;
> >> >> >> >> Applying pattern match.pd:111, gimple-match.c:27997
> >> >> >> >> Match-and-simplified s_4 - _1 to 0
> >> >> >> >> Intersecting
> >> >> >> >>   [0, 0]
> >> >> >> >> and
> >> >> >> >>   [0, +INF]
> >> >> >> >> to
> >> >> >> >>   [0, 0]
> >> >> >> >> Found new range for _7: [0, 0]
> >> >> >> >>
> >> >> >> >> __attribute__((noclone, noinline))
> >> >> >> >> fn1 (char * p, char * q)
> >> >> >> >> {
> >> >> >> >>   size_t s;
> >> >> >> >>   long unsigned in

Re: PR78153

[Prathamesh Kulkarni]

On 23 November 2016 at 15:16, Richard Biener <rguent...@suse.de> wrote:
> On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>
>> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
>> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >
>> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
>> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >
>> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
>> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >> >
>> >> >> >> Hi,
>> >> >> >> As suggested by Martin in PR78153 strlen's return value cannot 
>> >> >> >> exceed
>> >> >> >> PTRDIFF_MAX.
>> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
>> >> >> >> in the attached patch.
>> >> >> >>
>> >> >> >> However it regressed strlenopt-3.c:
>> >> >> >>
>> >> >> >> Consider fn1() from strlenopt-3.c:
>> >> >> >>
>> >> >> >> __attribute__((noinline, noclone)) size_t
>> >> >> >> fn1 (char *p, char *q)
>> >> >> >> {
>> >> >> >>   size_t s = strlen (q);
>> >> >> >>   strcpy (p, q);
>> >> >> >>   return s - strlen (p);
>> >> >> >> }
>> >> >> >>
>> >> >> >> The optimized dump shows the following:
>> >> >> >>
>> >> >> >> __attribute__((noclone, noinline))
>> >> >> >> fn1 (char * p, char * q)
>> >> >> >> {
>> >> >> >>   size_t s;
>> >> >> >>   size_t _7;
>> >> >> >>   long unsigned int _9;
>> >> >> >>
>> >> >> >>   :
>> >> >> >>   s_4 = strlen (q_3(D));
>> >> >> >>   _9 = s_4 + 1;
>> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >> >>   _7 = 0;
>> >> >> >>   return _7;
>> >> >> >>
>> >> >> >> }
>> >> >> >>
>> >> >> >> which introduces the regression, because the test expects "return 
>> >> >> >> 0;" in fn1().
>> >> >> >>
>> >> >> >> The issue seems to be in vrp2:
>> >> >> >>
>> >> >> >> Before the patch:
>> >> >> >> Visiting statement:
>> >> >> >> s_4 = strlen (q_3(D));
>> >> >> >> Found new range for s_4: VARYING
>> >> >> >>
>> >> >> >> Visiting statement:
>> >> >> >> _1 = s_4;
>> >> >> >> Found new range for _1: [s_4, s_4]
>> >> >> >> marking stmt to be not simulated again
>> >> >> >>
>> >> >> >> Visiting statement:
>> >> >> >> _7 = s_4 - _1;
>> >> >> >> Applying pattern match.pd:111, gimple-match.c:27997
>> >> >> >> Match-and-simplified s_4 - _1 to 0
>> >> >> >> Intersecting
>> >> >> >>   [0, 0]
>> >> >> >> and
>> >> >> >>   [0, +INF]
>> >> >> >> to
>> >> >> >>   [0, 0]
>> >> >> >> Found new range for _7: [0, 0]
>> >> >> >>
>> >> >> >> __attribute__((noclone, noinline))
>> >> >> >> fn1 (char * p, char * q)
>> >> >> >> {
>> >> >> >>   size_t s;
>> >> >> >>   long unsigned int _1;
>> >> >> >>   long unsigned int _9;
>> >> >> >>
>> >> >> >>   :
>> >> >> >>   s_4 = strlen (q_3(D));
>> >> >> >>   _9 = s_4 + 1;
>> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >> >>   _1 = s_4;
>> >> >> >>   return 0;
>> >> >> >>
>> >> >> >> }
>> >> >> >

Re: PR78153

[Richard Biener]

On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:

> On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >
> >> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
> >> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >> >
> >> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
> >> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
> >> >> >
> >> >> >> Hi,
> >> >> >> As suggested by Martin in PR78153 strlen's return value cannot exceed
> >> >> >> PTRDIFF_MAX.
> >> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
> >> >> >> in the attached patch.
> >> >> >>
> >> >> >> However it regressed strlenopt-3.c:
> >> >> >>
> >> >> >> Consider fn1() from strlenopt-3.c:
> >> >> >>
> >> >> >> __attribute__((noinline, noclone)) size_t
> >> >> >> fn1 (char *p, char *q)
> >> >> >> {
> >> >> >>   size_t s = strlen (q);
> >> >> >>   strcpy (p, q);
> >> >> >>   return s - strlen (p);
> >> >> >> }
> >> >> >>
> >> >> >> The optimized dump shows the following:
> >> >> >>
> >> >> >> __attribute__((noclone, noinline))
> >> >> >> fn1 (char * p, char * q)
> >> >> >> {
> >> >> >>   size_t s;
> >> >> >>   size_t _7;
> >> >> >>   long unsigned int _9;
> >> >> >>
> >> >> >>   :
> >> >> >>   s_4 = strlen (q_3(D));
> >> >> >>   _9 = s_4 + 1;
> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >> >>   _7 = 0;
> >> >> >>   return _7;
> >> >> >>
> >> >> >> }
> >> >> >>
> >> >> >> which introduces the regression, because the test expects "return 
> >> >> >> 0;" in fn1().
> >> >> >>
> >> >> >> The issue seems to be in vrp2:
> >> >> >>
> >> >> >> Before the patch:
> >> >> >> Visiting statement:
> >> >> >> s_4 = strlen (q_3(D));
> >> >> >> Found new range for s_4: VARYING
> >> >> >>
> >> >> >> Visiting statement:
> >> >> >> _1 = s_4;
> >> >> >> Found new range for _1: [s_4, s_4]
> >> >> >> marking stmt to be not simulated again
> >> >> >>
> >> >> >> Visiting statement:
> >> >> >> _7 = s_4 - _1;
> >> >> >> Applying pattern match.pd:111, gimple-match.c:27997
> >> >> >> Match-and-simplified s_4 - _1 to 0
> >> >> >> Intersecting
> >> >> >>   [0, 0]
> >> >> >> and
> >> >> >>   [0, +INF]
> >> >> >> to
> >> >> >>   [0, 0]
> >> >> >> Found new range for _7: [0, 0]
> >> >> >>
> >> >> >> __attribute__((noclone, noinline))
> >> >> >> fn1 (char * p, char * q)
> >> >> >> {
> >> >> >>   size_t s;
> >> >> >>   long unsigned int _1;
> >> >> >>   long unsigned int _9;
> >> >> >>
> >> >> >>   :
> >> >> >>   s_4 = strlen (q_3(D));
> >> >> >>   _9 = s_4 + 1;
> >> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >> >>   _1 = s_4;
> >> >> >>   return 0;
> >> >> >>
> >> >> >> }
> >> >> >>
> >> >> >>
> >> >> >> After the patch:
> >> >> >> Visiting statement:
> >> >> >> s_4 = strlen (q_3(D));
> >> >> >> Intersecting
> >> >> >>   [0, 9223372036854775806]
> >> >> >> and
> >> >> >>   [0, 9223372036854775806]
> >> >> >> to
> >> >> >>   [0, 9223372036854775

Re: PR78153

[Prathamesh Kulkarni]

On 22 November 2016 at 20:53, Richard Biener <rguent...@suse.de> wrote:
> On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>
>> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
>> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>> >
>> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
>> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>> >> >
>> >> >> Hi,
>> >> >> As suggested by Martin in PR78153 strlen's return value cannot exceed
>> >> >> PTRDIFF_MAX.
>> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
>> >> >> in the attached patch.
>> >> >>
>> >> >> However it regressed strlenopt-3.c:
>> >> >>
>> >> >> Consider fn1() from strlenopt-3.c:
>> >> >>
>> >> >> __attribute__((noinline, noclone)) size_t
>> >> >> fn1 (char *p, char *q)
>> >> >> {
>> >> >>   size_t s = strlen (q);
>> >> >>   strcpy (p, q);
>> >> >>   return s - strlen (p);
>> >> >> }
>> >> >>
>> >> >> The optimized dump shows the following:
>> >> >>
>> >> >> __attribute__((noclone, noinline))
>> >> >> fn1 (char * p, char * q)
>> >> >> {
>> >> >>   size_t s;
>> >> >>   size_t _7;
>> >> >>   long unsigned int _9;
>> >> >>
>> >> >>   :
>> >> >>   s_4 = strlen (q_3(D));
>> >> >>   _9 = s_4 + 1;
>> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >>   _7 = 0;
>> >> >>   return _7;
>> >> >>
>> >> >> }
>> >> >>
>> >> >> which introduces the regression, because the test expects "return 0;" 
>> >> >> in fn1().
>> >> >>
>> >> >> The issue seems to be in vrp2:
>> >> >>
>> >> >> Before the patch:
>> >> >> Visiting statement:
>> >> >> s_4 = strlen (q_3(D));
>> >> >> Found new range for s_4: VARYING
>> >> >>
>> >> >> Visiting statement:
>> >> >> _1 = s_4;
>> >> >> Found new range for _1: [s_4, s_4]
>> >> >> marking stmt to be not simulated again
>> >> >>
>> >> >> Visiting statement:
>> >> >> _7 = s_4 - _1;
>> >> >> Applying pattern match.pd:111, gimple-match.c:27997
>> >> >> Match-and-simplified s_4 - _1 to 0
>> >> >> Intersecting
>> >> >>   [0, 0]
>> >> >> and
>> >> >>   [0, +INF]
>> >> >> to
>> >> >>   [0, 0]
>> >> >> Found new range for _7: [0, 0]
>> >> >>
>> >> >> __attribute__((noclone, noinline))
>> >> >> fn1 (char * p, char * q)
>> >> >> {
>> >> >>   size_t s;
>> >> >>   long unsigned int _1;
>> >> >>   long unsigned int _9;
>> >> >>
>> >> >>   :
>> >> >>   s_4 = strlen (q_3(D));
>> >> >>   _9 = s_4 + 1;
>> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >> >>   _1 = s_4;
>> >> >>   return 0;
>> >> >>
>> >> >> }
>> >> >>
>> >> >>
>> >> >> After the patch:
>> >> >> Visiting statement:
>> >> >> s_4 = strlen (q_3(D));
>> >> >> Intersecting
>> >> >>   [0, 9223372036854775806]
>> >> >> and
>> >> >>   [0, 9223372036854775806]
>> >> >> to
>> >> >>   [0, 9223372036854775806]
>> >> >> Found new range for s_4: [0, 9223372036854775806]
>> >> >> marking stmt to be not simulated again
>> >> >>
>> >> >> Visiting statement:
>> >> >> _1 = s_4;
>> >> >> Intersecting
>> >> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
>> >> >> and
>> >> >>   [0, 9223372036854775806]
>> >> >> to
>> >> >>   [0, 92233

Re: PR78153

[Richard Biener]

On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:

> On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
> > On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
> >
> >> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
> >> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
> >> >
> >> >> Hi,
> >> >> As suggested by Martin in PR78153 strlen's return value cannot exceed
> >> >> PTRDIFF_MAX.
> >> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
> >> >> in the attached patch.
> >> >>
> >> >> However it regressed strlenopt-3.c:
> >> >>
> >> >> Consider fn1() from strlenopt-3.c:
> >> >>
> >> >> __attribute__((noinline, noclone)) size_t
> >> >> fn1 (char *p, char *q)
> >> >> {
> >> >>   size_t s = strlen (q);
> >> >>   strcpy (p, q);
> >> >>   return s - strlen (p);
> >> >> }
> >> >>
> >> >> The optimized dump shows the following:
> >> >>
> >> >> __attribute__((noclone, noinline))
> >> >> fn1 (char * p, char * q)
> >> >> {
> >> >>   size_t s;
> >> >>   size_t _7;
> >> >>   long unsigned int _9;
> >> >>
> >> >>   :
> >> >>   s_4 = strlen (q_3(D));
> >> >>   _9 = s_4 + 1;
> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >>   _7 = 0;
> >> >>   return _7;
> >> >>
> >> >> }
> >> >>
> >> >> which introduces the regression, because the test expects "return 0;" 
> >> >> in fn1().
> >> >>
> >> >> The issue seems to be in vrp2:
> >> >>
> >> >> Before the patch:
> >> >> Visiting statement:
> >> >> s_4 = strlen (q_3(D));
> >> >> Found new range for s_4: VARYING
> >> >>
> >> >> Visiting statement:
> >> >> _1 = s_4;
> >> >> Found new range for _1: [s_4, s_4]
> >> >> marking stmt to be not simulated again
> >> >>
> >> >> Visiting statement:
> >> >> _7 = s_4 - _1;
> >> >> Applying pattern match.pd:111, gimple-match.c:27997
> >> >> Match-and-simplified s_4 - _1 to 0
> >> >> Intersecting
> >> >>   [0, 0]
> >> >> and
> >> >>   [0, +INF]
> >> >> to
> >> >>   [0, 0]
> >> >> Found new range for _7: [0, 0]
> >> >>
> >> >> __attribute__((noclone, noinline))
> >> >> fn1 (char * p, char * q)
> >> >> {
> >> >>   size_t s;
> >> >>   long unsigned int _1;
> >> >>   long unsigned int _9;
> >> >>
> >> >>   :
> >> >>   s_4 = strlen (q_3(D));
> >> >>   _9 = s_4 + 1;
> >> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >> >>   _1 = s_4;
> >> >>   return 0;
> >> >>
> >> >> }
> >> >>
> >> >>
> >> >> After the patch:
> >> >> Visiting statement:
> >> >> s_4 = strlen (q_3(D));
> >> >> Intersecting
> >> >>   [0, 9223372036854775806]
> >> >> and
> >> >>   [0, 9223372036854775806]
> >> >> to
> >> >>   [0, 9223372036854775806]
> >> >> Found new range for s_4: [0, 9223372036854775806]
> >> >> marking stmt to be not simulated again
> >> >>
> >> >> Visiting statement:
> >> >> _1 = s_4;
> >> >> Intersecting
> >> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> >> >> and
> >> >>   [0, 9223372036854775806]
> >> >> to
> >> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> >> >> Found new range for _1: [0, 9223372036854775806]
> >> >> marking stmt to be not simulated again
> >> >>
> >> >> Visiting statement:
> >> >> _7 = s_4 - _1;
> >> >> Intersecting
> >> >>   ~[9223372036854775807, 9223372036854775809]
> >> >> and
> >> >>   ~[9223372036854775807, 9223372036854775809]
> >> >> 

Re: PR78153

[Prathamesh Kulkarni]

On 22 November 2016 at 20:18, Richard Biener <rguent...@suse.de> wrote:
> On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:
>
>> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
>> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>> >
>> >> Hi,
>> >> As suggested by Martin in PR78153 strlen's return value cannot exceed
>> >> PTRDIFF_MAX.
>> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
>> >> in the attached patch.
>> >>
>> >> However it regressed strlenopt-3.c:
>> >>
>> >> Consider fn1() from strlenopt-3.c:
>> >>
>> >> __attribute__((noinline, noclone)) size_t
>> >> fn1 (char *p, char *q)
>> >> {
>> >>   size_t s = strlen (q);
>> >>   strcpy (p, q);
>> >>   return s - strlen (p);
>> >> }
>> >>
>> >> The optimized dump shows the following:
>> >>
>> >> __attribute__((noclone, noinline))
>> >> fn1 (char * p, char * q)
>> >> {
>> >>   size_t s;
>> >>   size_t _7;
>> >>   long unsigned int _9;
>> >>
>> >>   :
>> >>   s_4 = strlen (q_3(D));
>> >>   _9 = s_4 + 1;
>> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >>   _7 = 0;
>> >>   return _7;
>> >>
>> >> }
>> >>
>> >> which introduces the regression, because the test expects "return 0;" in 
>> >> fn1().
>> >>
>> >> The issue seems to be in vrp2:
>> >>
>> >> Before the patch:
>> >> Visiting statement:
>> >> s_4 = strlen (q_3(D));
>> >> Found new range for s_4: VARYING
>> >>
>> >> Visiting statement:
>> >> _1 = s_4;
>> >> Found new range for _1: [s_4, s_4]
>> >> marking stmt to be not simulated again
>> >>
>> >> Visiting statement:
>> >> _7 = s_4 - _1;
>> >> Applying pattern match.pd:111, gimple-match.c:27997
>> >> Match-and-simplified s_4 - _1 to 0
>> >> Intersecting
>> >>   [0, 0]
>> >> and
>> >>   [0, +INF]
>> >> to
>> >>   [0, 0]
>> >> Found new range for _7: [0, 0]
>> >>
>> >> __attribute__((noclone, noinline))
>> >> fn1 (char * p, char * q)
>> >> {
>> >>   size_t s;
>> >>   long unsigned int _1;
>> >>   long unsigned int _9;
>> >>
>> >>   :
>> >>   s_4 = strlen (q_3(D));
>> >>   _9 = s_4 + 1;
>> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
>> >>   _1 = s_4;
>> >>   return 0;
>> >>
>> >> }
>> >>
>> >>
>> >> After the patch:
>> >> Visiting statement:
>> >> s_4 = strlen (q_3(D));
>> >> Intersecting
>> >>   [0, 9223372036854775806]
>> >> and
>> >>   [0, 9223372036854775806]
>> >> to
>> >>   [0, 9223372036854775806]
>> >> Found new range for s_4: [0, 9223372036854775806]
>> >> marking stmt to be not simulated again
>> >>
>> >> Visiting statement:
>> >> _1 = s_4;
>> >> Intersecting
>> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
>> >> and
>> >>   [0, 9223372036854775806]
>> >> to
>> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
>> >> Found new range for _1: [0, 9223372036854775806]
>> >> marking stmt to be not simulated again
>> >>
>> >> Visiting statement:
>> >> _7 = s_4 - _1;
>> >> Intersecting
>> >>   ~[9223372036854775807, 9223372036854775809]
>> >> and
>> >>   ~[9223372036854775807, 9223372036854775809]
>> >> to
>> >>   ~[9223372036854775807, 9223372036854775809]
>> >> Found new range for _7: ~[9223372036854775807, 9223372036854775809]
>> >> marking stmt to be not simulated again
>> >>
>> >> __attribute__((noclone, noinline))
>> >> fn1 (char * p, char * q)
>> >> {
>> >>   size_t s;
>> >>   long unsigned int _1;
>> >>   size_t _7;
>> >>   long unsigned int _9;
>> >>
>> >>   :
>> >>   s_4 = strlen (q_3(D));
>> >>   _9 = s_4 + 1;
>> >> 

Re: PR78153

[Richard Biener]

On Tue, 22 Nov 2016, Prathamesh Kulkarni wrote:

> On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
> > On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
> >
> >> Hi,
> >> As suggested by Martin in PR78153 strlen's return value cannot exceed
> >> PTRDIFF_MAX.
> >> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
> >> in the attached patch.
> >>
> >> However it regressed strlenopt-3.c:
> >>
> >> Consider fn1() from strlenopt-3.c:
> >>
> >> __attribute__((noinline, noclone)) size_t
> >> fn1 (char *p, char *q)
> >> {
> >>   size_t s = strlen (q);
> >>   strcpy (p, q);
> >>   return s - strlen (p);
> >> }
> >>
> >> The optimized dump shows the following:
> >>
> >> __attribute__((noclone, noinline))
> >> fn1 (char * p, char * q)
> >> {
> >>   size_t s;
> >>   size_t _7;
> >>   long unsigned int _9;
> >>
> >>   :
> >>   s_4 = strlen (q_3(D));
> >>   _9 = s_4 + 1;
> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >>   _7 = 0;
> >>   return _7;
> >>
> >> }
> >>
> >> which introduces the regression, because the test expects "return 0;" in 
> >> fn1().
> >>
> >> The issue seems to be in vrp2:
> >>
> >> Before the patch:
> >> Visiting statement:
> >> s_4 = strlen (q_3(D));
> >> Found new range for s_4: VARYING
> >>
> >> Visiting statement:
> >> _1 = s_4;
> >> Found new range for _1: [s_4, s_4]
> >> marking stmt to be not simulated again
> >>
> >> Visiting statement:
> >> _7 = s_4 - _1;
> >> Applying pattern match.pd:111, gimple-match.c:27997
> >> Match-and-simplified s_4 - _1 to 0
> >> Intersecting
> >>   [0, 0]
> >> and
> >>   [0, +INF]
> >> to
> >>   [0, 0]
> >> Found new range for _7: [0, 0]
> >>
> >> __attribute__((noclone, noinline))
> >> fn1 (char * p, char * q)
> >> {
> >>   size_t s;
> >>   long unsigned int _1;
> >>   long unsigned int _9;
> >>
> >>   :
> >>   s_4 = strlen (q_3(D));
> >>   _9 = s_4 + 1;
> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >>   _1 = s_4;
> >>   return 0;
> >>
> >> }
> >>
> >>
> >> After the patch:
> >> Visiting statement:
> >> s_4 = strlen (q_3(D));
> >> Intersecting
> >>   [0, 9223372036854775806]
> >> and
> >>   [0, 9223372036854775806]
> >> to
> >>   [0, 9223372036854775806]
> >> Found new range for s_4: [0, 9223372036854775806]
> >> marking stmt to be not simulated again
> >>
> >> Visiting statement:
> >> _1 = s_4;
> >> Intersecting
> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> >> and
> >>   [0, 9223372036854775806]
> >> to
> >>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> >> Found new range for _1: [0, 9223372036854775806]
> >> marking stmt to be not simulated again
> >>
> >> Visiting statement:
> >> _7 = s_4 - _1;
> >> Intersecting
> >>   ~[9223372036854775807, 9223372036854775809]
> >> and
> >>   ~[9223372036854775807, 9223372036854775809]
> >> to
> >>   ~[9223372036854775807, 9223372036854775809]
> >> Found new range for _7: ~[9223372036854775807, 9223372036854775809]
> >> marking stmt to be not simulated again
> >>
> >> __attribute__((noclone, noinline))
> >> fn1 (char * p, char * q)
> >> {
> >>   size_t s;
> >>   long unsigned int _1;
> >>   size_t _7;
> >>   long unsigned int _9;
> >>
> >>   :
> >>   s_4 = strlen (q_3(D));
> >>   _9 = s_4 + 1;
> >>   __builtin_memcpy (p_5(D), q_3(D), _9);
> >>   _1 = s_4;
> >>   _7 = s_4 - _1;
> >>   return _7;
> >>
> >> }
> >>
> >> Then forwprop4 turns
> >> _1 = s_4
> >> _7 = s_4 - _1
> >> into
> >> _7 = 0
> >>
> >> and we end up with:
> >> _7 = 0
> >> return _7
> >> in optimized dump.
> >>
> >> Running ccp again after forwprop4 trivially solves the issue, however
> >> I am not sure if we want to run ccp again ?
> >>
> >> T

Re: PR78153

[Prathamesh Kulkarni]

On 21 November 2016 at 15:10, Richard Biener <rguent...@suse.de> wrote:
> On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:
>
>> Hi,
>> As suggested by Martin in PR78153 strlen's return value cannot exceed
>> PTRDIFF_MAX.
>> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
>> in the attached patch.
>>
>> However it regressed strlenopt-3.c:
>>
>> Consider fn1() from strlenopt-3.c:
>>
>> __attribute__((noinline, noclone)) size_t
>> fn1 (char *p, char *q)
>> {
>>   size_t s = strlen (q);
>>   strcpy (p, q);
>>   return s - strlen (p);
>> }
>>
>> The optimized dump shows the following:
>>
>> __attribute__((noclone, noinline))
>> fn1 (char * p, char * q)
>> {
>>   size_t s;
>>   size_t _7;
>>   long unsigned int _9;
>>
>>   :
>>   s_4 = strlen (q_3(D));
>>   _9 = s_4 + 1;
>>   __builtin_memcpy (p_5(D), q_3(D), _9);
>>   _7 = 0;
>>   return _7;
>>
>> }
>>
>> which introduces the regression, because the test expects "return 0;" in 
>> fn1().
>>
>> The issue seems to be in vrp2:
>>
>> Before the patch:
>> Visiting statement:
>> s_4 = strlen (q_3(D));
>> Found new range for s_4: VARYING
>>
>> Visiting statement:
>> _1 = s_4;
>> Found new range for _1: [s_4, s_4]
>> marking stmt to be not simulated again
>>
>> Visiting statement:
>> _7 = s_4 - _1;
>> Applying pattern match.pd:111, gimple-match.c:27997
>> Match-and-simplified s_4 - _1 to 0
>> Intersecting
>>   [0, 0]
>> and
>>   [0, +INF]
>> to
>>   [0, 0]
>> Found new range for _7: [0, 0]
>>
>> __attribute__((noclone, noinline))
>> fn1 (char * p, char * q)
>> {
>>   size_t s;
>>   long unsigned int _1;
>>   long unsigned int _9;
>>
>>   :
>>   s_4 = strlen (q_3(D));
>>   _9 = s_4 + 1;
>>   __builtin_memcpy (p_5(D), q_3(D), _9);
>>   _1 = s_4;
>>   return 0;
>>
>> }
>>
>>
>> After the patch:
>> Visiting statement:
>> s_4 = strlen (q_3(D));
>> Intersecting
>>   [0, 9223372036854775806]
>> and
>>   [0, 9223372036854775806]
>> to
>>   [0, 9223372036854775806]
>> Found new range for s_4: [0, 9223372036854775806]
>> marking stmt to be not simulated again
>>
>> Visiting statement:
>> _1 = s_4;
>> Intersecting
>>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
>> and
>>   [0, 9223372036854775806]
>> to
>>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
>> Found new range for _1: [0, 9223372036854775806]
>> marking stmt to be not simulated again
>>
>> Visiting statement:
>> _7 = s_4 - _1;
>> Intersecting
>>   ~[9223372036854775807, 9223372036854775809]
>> and
>>   ~[9223372036854775807, 9223372036854775809]
>> to
>>   ~[9223372036854775807, 9223372036854775809]
>> Found new range for _7: ~[9223372036854775807, 9223372036854775809]
>> marking stmt to be not simulated again
>>
>> __attribute__((noclone, noinline))
>> fn1 (char * p, char * q)
>> {
>>   size_t s;
>>   long unsigned int _1;
>>   size_t _7;
>>   long unsigned int _9;
>>
>>   :
>>   s_4 = strlen (q_3(D));
>>   _9 = s_4 + 1;
>>   __builtin_memcpy (p_5(D), q_3(D), _9);
>>   _1 = s_4;
>>   _7 = s_4 - _1;
>>   return _7;
>>
>> }
>>
>> Then forwprop4 turns
>> _1 = s_4
>> _7 = s_4 - _1
>> into
>> _7 = 0
>>
>> and we end up with:
>> _7 = 0
>> return _7
>> in optimized dump.
>>
>> Running ccp again after forwprop4 trivially solves the issue, however
>> I am not sure if we want to run ccp again ?
>>
>> The issue is probably with extract_range_from_ssa_name():
>> For _1 = s_4
>>
>> Before patch:
>> VR for s_4 is set to varying.
>> So VR for _1 is set to [s_4, s_4] by extract_range_from_ssa_name.
>> Since VR for _1 is [s_4, s_4] it implicitly implies that _1 is equal to s_4,
>> and vrp is able to transform _7 = s_4 - _1 to _7 = 0 (by using
>> match.pd pattern x - x -> 0).
>>
>> After patch:
>> VR for s_4 is set to [0, PTRDIFF_MAX - 1]
>> And correspondingly VR for _1 is set to [0, PTRDIFF_MAX - 1]
>> so IIUC, we then lose the information that _1 is equal to s_4,
>
> We don't lose it, it's in its set of equivalencies.
Ah, I missed that, thanks. For some reason I had mis-conception that
equivalences stor

Re: PR78153

[Richard Biener]

On Sun, 20 Nov 2016, Prathamesh Kulkarni wrote:

> Hi,
> As suggested by Martin in PR78153 strlen's return value cannot exceed
> PTRDIFF_MAX.
> So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
> in the attached patch.
> 
> However it regressed strlenopt-3.c:
> 
> Consider fn1() from strlenopt-3.c:
> 
> __attribute__((noinline, noclone)) size_t
> fn1 (char *p, char *q)
> {
>   size_t s = strlen (q);
>   strcpy (p, q);
>   return s - strlen (p);
> }
> 
> The optimized dump shows the following:
> 
> __attribute__((noclone, noinline))
> fn1 (char * p, char * q)
> {
>   size_t s;
>   size_t _7;
>   long unsigned int _9;
> 
>   :
>   s_4 = strlen (q_3(D));
>   _9 = s_4 + 1;
>   __builtin_memcpy (p_5(D), q_3(D), _9);
>   _7 = 0;
>   return _7;
> 
> }
> 
> which introduces the regression, because the test expects "return 0;" in 
> fn1().
> 
> The issue seems to be in vrp2:
> 
> Before the patch:
> Visiting statement:
> s_4 = strlen (q_3(D));
> Found new range for s_4: VARYING
> 
> Visiting statement:
> _1 = s_4;
> Found new range for _1: [s_4, s_4]
> marking stmt to be not simulated again
> 
> Visiting statement:
> _7 = s_4 - _1;
> Applying pattern match.pd:111, gimple-match.c:27997
> Match-and-simplified s_4 - _1 to 0
> Intersecting
>   [0, 0]
> and
>   [0, +INF]
> to
>   [0, 0]
> Found new range for _7: [0, 0]
> 
> __attribute__((noclone, noinline))
> fn1 (char * p, char * q)
> {
>   size_t s;
>   long unsigned int _1;
>   long unsigned int _9;
> 
>   :
>   s_4 = strlen (q_3(D));
>   _9 = s_4 + 1;
>   __builtin_memcpy (p_5(D), q_3(D), _9);
>   _1 = s_4;
>   return 0;
> 
> }
> 
> 
> After the patch:
> Visiting statement:
> s_4 = strlen (q_3(D));
> Intersecting
>   [0, 9223372036854775806]
> and
>   [0, 9223372036854775806]
> to
>   [0, 9223372036854775806]
> Found new range for s_4: [0, 9223372036854775806]
> marking stmt to be not simulated again
> 
> Visiting statement:
> _1 = s_4;
> Intersecting
>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> and
>   [0, 9223372036854775806]
> to
>   [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
> Found new range for _1: [0, 9223372036854775806]
> marking stmt to be not simulated again
> 
> Visiting statement:
> _7 = s_4 - _1;
> Intersecting
>   ~[9223372036854775807, 9223372036854775809]
> and
>   ~[9223372036854775807, 9223372036854775809]
> to
>   ~[9223372036854775807, 9223372036854775809]
> Found new range for _7: ~[9223372036854775807, 9223372036854775809]
> marking stmt to be not simulated again
> 
> __attribute__((noclone, noinline))
> fn1 (char * p, char * q)
> {
>   size_t s;
>   long unsigned int _1;
>   size_t _7;
>   long unsigned int _9;
> 
>   :
>   s_4 = strlen (q_3(D));
>   _9 = s_4 + 1;
>   __builtin_memcpy (p_5(D), q_3(D), _9);
>   _1 = s_4;
>   _7 = s_4 - _1;
>   return _7;
> 
> }
> 
> Then forwprop4 turns
> _1 = s_4
> _7 = s_4 - _1
> into
> _7 = 0
> 
> and we end up with:
> _7 = 0
> return _7
> in optimized dump.
> 
> Running ccp again after forwprop4 trivially solves the issue, however
> I am not sure if we want to run ccp again ?
> 
> The issue is probably with extract_range_from_ssa_name():
> For _1 = s_4
> 
> Before patch:
> VR for s_4 is set to varying.
> So VR for _1 is set to [s_4, s_4] by extract_range_from_ssa_name.
> Since VR for _1 is [s_4, s_4] it implicitly implies that _1 is equal to s_4,
> and vrp is able to transform _7 = s_4 - _1 to _7 = 0 (by using
> match.pd pattern x - x -> 0).
> 
> After patch:
> VR for s_4 is set to [0, PTRDIFF_MAX - 1]
> And correspondingly VR for _1 is set to [0, PTRDIFF_MAX - 1]
> so IIUC, we then lose the information that _1 is equal to s_4,

We don't lose it, it's in its set of equivalencies.

> and vrp doesn't transform _7 = s_4 - _1 to _7 = 0.
> forwprop4 does that because it sees that s_4 and _1 are equivalent.
> Does this sound correct ?

Yes.  So the issue is really that vrp_visit_assignment_or_call calls
gimple_fold_stmt_to_constant_1 with vrp_valueize[_1] which when
we do not have a singleton VR_RANGE does not fall back to looking
at equivalences (there's not a good cheap way to do that currently because
VRP doesn't keep a proper copy lattice but simply IORs equivalences
from all equivalences).  In theory simply using the first set bit
might work.  Thus sth like

@@ -7057,6 +7030,12 @@ vrp_valueize (tree name)
  || is_gimple_min_invariant (vr->min))
  && vrp_operand_equal_p (vr->min, vr->max))
return vr->min;
+  else if (vr->equiv && ! bitmap_empty_p (vr->equiv))
+   {
+ unsigned num = bitmap_first_set_bit (vr->equiv);
+ if (num < SSA_NAME_VERSION (name))
+   return ssa_name (num);
+   }
 }
   return name;
 }

might work with the idea of simply doing canonicalization to one of
the equivalences.  But as we don't allow copies in the SSA def stmt
(via vrp_valueize_1) I'm not sure that's good enough canonicalization.

Richard.

Re: PR78153

[Prathamesh Kulkarni]

On 20 November 2016 at 19:34, Jakub Jelinek  wrote:
> On Sun, Nov 20, 2016 at 07:20:20PM +0530, Prathamesh Kulkarni wrote:
>> --- a/gcc/tree-vrp.c
>> +++ b/gcc/tree-vrp.c
>> @@ -4013,6 +4013,16 @@ extract_range_basic (value_range *vr, gimple *stmt)
>> : vrp_val_max (type), NULL);
>> }
>> return;
>> + case CFN_BUILT_IN_STRLEN:
>> +   {
>> + tree type = TREE_TYPE (gimple_call_lhs (stmt));
>> + unsigned HOST_WIDE_INT max =
>> + TREE_INT_CST_LOW (vrp_val_max (ptrdiff_type_node)) - 1;
>
> Wrong formatting, = should go on the next line, and should be indented only
> 2 columns more than the previous line.  Plus TREE_INT_CST_LOW really
> shouldn't be used in new code.  You should use tree_to_uhwi or tree_to_shwi
> instead.  Why the -1?  Can you just
> fold_convert (type, TYPE_MAX_VALUE (ptrdiff_type_node)); ?
> Or, if you really want the -1, e.g. wide_int max = vrp_val_max 
> (ptrdiff_type_node);
> wide_int_to_tree (type, max - 1);
> or something similar.
Hi Jakub,
Thanks for the suggestions.
Sorry I wrote misleading info in the patch. As per PR, strlen's return value
should always be less than PTRDIFF_MAX, so I am setting the range to
[0, PTRDIFF_MAX - 1].
I will use wide_int in the next version of patch.

Thanks,
Prathamesh
>> +
>> + set_value_range (vr, VR_RANGE, build_int_cst (type, 0),
>> +  build_int_cst (type, max), NULL);
>> +   }
>> +   return;
>>   default:
>> break;
>>   }
>
> Jakub

Re: PR78153

[Jakub Jelinek]

On Sun, Nov 20, 2016 at 07:20:20PM +0530, Prathamesh Kulkarni wrote:
> --- a/gcc/tree-vrp.c
> +++ b/gcc/tree-vrp.c
> @@ -4013,6 +4013,16 @@ extract_range_basic (value_range *vr, gimple *stmt)
> : vrp_val_max (type), NULL);
> }
> return;
> + case CFN_BUILT_IN_STRLEN:
> +   {
> + tree type = TREE_TYPE (gimple_call_lhs (stmt));
> + unsigned HOST_WIDE_INT max =
> + TREE_INT_CST_LOW (vrp_val_max (ptrdiff_type_node)) - 1;

Wrong formatting, = should go on the next line, and should be indented only
2 columns more than the previous line.  Plus TREE_INT_CST_LOW really
shouldn't be used in new code.  You should use tree_to_uhwi or tree_to_shwi
instead.  Why the -1?  Can you just
fold_convert (type, TYPE_MAX_VALUE (ptrdiff_type_node)); ?
Or, if you really want the -1, e.g. wide_int max = vrp_val_max 
(ptrdiff_type_node);
wide_int_to_tree (type, max - 1);
or something similar.
> +
> + set_value_range (vr, VR_RANGE, build_int_cst (type, 0),
> +  build_int_cst (type, max), NULL);
> +   }
> +   return;
>   default:
> break;
>   }

Jakub

PR78153

[Prathamesh Kulkarni]

Hi,
As suggested by Martin in PR78153 strlen's return value cannot exceed
PTRDIFF_MAX.
So I set it's range to [0, PTRDIFF_MAX - 1] in extract_range_basic()
in the attached patch.

However it regressed strlenopt-3.c:

Consider fn1() from strlenopt-3.c:

__attribute__((noinline, noclone)) size_t
fn1 (char *p, char *q)
{
  size_t s = strlen (q);
  strcpy (p, q);
  return s - strlen (p);
}

The optimized dump shows the following:

__attribute__((noclone, noinline))
fn1 (char * p, char * q)
{
  size_t s;
  size_t _7;
  long unsigned int _9;

  :
  s_4 = strlen (q_3(D));
  _9 = s_4 + 1;
  __builtin_memcpy (p_5(D), q_3(D), _9);
  _7 = 0;
  return _7;

}

which introduces the regression, because the test expects "return 0;" in fn1().

The issue seems to be in vrp2:

Before the patch:
Visiting statement:
s_4 = strlen (q_3(D));
Found new range for s_4: VARYING

Visiting statement:
_1 = s_4;
Found new range for _1: [s_4, s_4]
marking stmt to be not simulated again

Visiting statement:
_7 = s_4 - _1;
Applying pattern match.pd:111, gimple-match.c:27997
Match-and-simplified s_4 - _1 to 0
Intersecting
  [0, 0]
and
  [0, +INF]
to
  [0, 0]
Found new range for _7: [0, 0]

__attribute__((noclone, noinline))
fn1 (char * p, char * q)
{
  size_t s;
  long unsigned int _1;
  long unsigned int _9;

  :
  s_4 = strlen (q_3(D));
  _9 = s_4 + 1;
  __builtin_memcpy (p_5(D), q_3(D), _9);
  _1 = s_4;
  return 0;

}


After the patch:
Visiting statement:
s_4 = strlen (q_3(D));
Intersecting
  [0, 9223372036854775806]
and
  [0, 9223372036854775806]
to
  [0, 9223372036854775806]
Found new range for s_4: [0, 9223372036854775806]
marking stmt to be not simulated again

Visiting statement:
_1 = s_4;
Intersecting
  [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
and
  [0, 9223372036854775806]
to
  [0, 9223372036854775806]  EQUIVALENCES: { s_4 } (1 elements)
Found new range for _1: [0, 9223372036854775806]
marking stmt to be not simulated again

Visiting statement:
_7 = s_4 - _1;
Intersecting
  ~[9223372036854775807, 9223372036854775809]
and
  ~[9223372036854775807, 9223372036854775809]
to
  ~[9223372036854775807, 9223372036854775809]
Found new range for _7: ~[9223372036854775807, 9223372036854775809]
marking stmt to be not simulated again

__attribute__((noclone, noinline))
fn1 (char * p, char * q)
{
  size_t s;
  long unsigned int _1;
  size_t _7;
  long unsigned int _9;

  :
  s_4 = strlen (q_3(D));
  _9 = s_4 + 1;
  __builtin_memcpy (p_5(D), q_3(D), _9);
  _1 = s_4;
  _7 = s_4 - _1;
  return _7;

}

Then forwprop4 turns
_1 = s_4
_7 = s_4 - _1
into
_7 = 0

and we end up with:
_7 = 0
return _7
in optimized dump.

Running ccp again after forwprop4 trivially solves the issue, however
I am not sure if we want to run ccp again ?

The issue is probably with extract_range_from_ssa_name():
For _1 = s_4

Before patch:
VR for s_4 is set to varying.
So VR for _1 is set to [s_4, s_4] by extract_range_from_ssa_name.
Since VR for _1 is [s_4, s_4] it implicitly implies that _1 is equal to s_4,
and vrp is able to transform _7 = s_4 - _1 to _7 = 0 (by using
match.pd pattern x - x -> 0).

After patch:
VR for s_4 is set to [0, PTRDIFF_MAX - 1]
And correspondingly VR for _1 is set to [0, PTRDIFF_MAX - 1]
so IIUC, we then lose the information that _1 is equal to s_4,
and vrp doesn't transform _7 = s_4 - _1 to _7 = 0.
forwprop4 does that because it sees that s_4 and _1 are equivalent.
Does this sound correct ?

I am not sure how to proceed with the patch,
and would be grateful for suggestions.

Thanks,
Prathamesh
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr78153-1.c 
b/gcc/testsuite/gcc.dg/tree-ssa/pr78153-1.c
new file mode 100644
index 000..2530ba0
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr78153-1.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-evrp-slim" } */
+
+void f(const char *s)
+{
+  if (__PTRDIFF_MAX__ <= __builtin_strlen (s))
+__builtin_abort ();
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_abort" "evrp" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr78153-2.c 
b/gcc/testsuite/gcc.dg/tree-ssa/pr78153-2.c
new file mode 100644
index 000..de70450
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr78153-2.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-evrp-slim" } */
+
+void f(const char *s)
+{
+  __PTRDIFF_TYPE__ n = __builtin_strlen (s);
+  if (n < 0)
+__builtin_abort ();
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_abort" "evrp" } } */
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index c2a4133..d17b413 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -4013,6 +4013,16 @@ extract_range_basic (value_range *vr, gimple *stmt)
  : vrp_val_max (type), NULL);
  }
  return;
+   case CFN_BUILT_IN_STRLEN:
+ {
+   tree type = TREE_TYPE (gimple_call_lhs (stmt));
+   unsigned HOST_WIDE_I