[Bug tree-optimization/92408] strlen(s) != 0 not folded into *s

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92408

Andrew Pinski  changed:

   What|Removed |Added

 Status|NEW |ASSIGNED
   Assignee|unassigned at gcc dot gnu.org  |pinskia at gcc dot 
gnu.org

--- Comment #4 from Andrew Pinski  ---
I am going to implement this for GCC 16. forwprop seems like a reasonible
place.

Basically for a strlen statement that is only used with a comparison with
`==/!= 0` get both replaced with `*a ==/!= 0`. Note since result of strlen is
unsigned we don't need to handle `>= 1` or `> 1` since those will be replaced
with `!= 0`.

[Bug tree-optimization/92408] strlen(s) != 0 not folded into *s

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92408

Andrew Pinski  changed:

   What|Removed |Added

 CC||pinskia at gcc dot gnu.org

--- Comment #3 from Andrew Pinski  ---
I wonder if this could be done im gimple fold or forwprop.

[Bug tree-optimization/92408] strlen(s) != 0 not folded into *s

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92408

Andrew Pinski  changed:

   What|Removed |Added

 Ever confirmed|0   |1
   Severity|normal  |enhancement
 Status|UNCONFIRMED |NEW
  Component|middle-end  |tree-optimization
   Last reconfirmed||2021-08-01

--- Comment #2 from Andrew Pinski  ---
Confirmed.
The code is located in fold_binary_loc in fold-const.c, moving it to match.pd
might need some patching to support adding of loads in the case of
-fnon-call-exceptions.