[Cocci] elision of unneeded parens

[Cocci] elision of unneeded parens

[ron minnich]

I've had someone request something and I want to show them how cool
coccinnelle is. If only I were smart enough!

There are lots of things like this:
if ((a == b) && (c != e))

which I'd like to turn in to
if (a == b && c == d) ...

anyway, is this one simple?

ron
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://systeme.lip6.fr/pipermail/cocci/attachments/20151012/f11d93f8/attachment.html>

[Cocci] elision of unneeded parens

[Peter Senna Tschudin]

On Mon, Oct 12, 2015 at 11:38 PM, ron minnich <rminnich@gmail.com> wrote:
> I've had someone request something and I want to show them how cool
> coccinnelle is. If only I were smart enough!
>
> There are lots of things like this:
> if ((a == b) && (c != e))
>
> which I'd like to turn in to
> if (a == b && c == d) ...
Where does d comes from?

[Cocci] elision of unneeded parens

[ron minnich]

wow, I can't type.

Let me say it more sensibly, even if wrong :-)
[[[ I know this is wrong, it's kind of "what I want it to do" ]]]

@@
expression E1, E2;
statement S;
function f;
@@
f(...){<...
-if ((E1) && (E2))
+if (E1 && E2)
S
...> }

Is that any more sensible?

thanks

ron

On Mon, Oct 12, 2015 at 2:43 PM Peter Senna Tschudin <peter.senna@gmail.com>
wrote:

> On Mon, Oct 12, 2015 at 11:38 PM, ron minnich <rminnich@gmail.com> wrote:
> > I've had someone request something and I want to show them how cool
> > coccinnelle is. If only I were smart enough!
> >
> > There are lots of things like this:
> > if ((a == b) && (c != e))
> >
> > which I'd like to turn in to
> > if (a == b && c == d) ...
> Where does d comes from?
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://systeme.lip6.fr/pipermail/cocci/attachments/20151012/ed61135b/attachment.html>

[Cocci] elision of unneeded parens

[Peter Senna Tschudin]

On Mon, Oct 12, 2015 at 11:45 PM, ron minnich <rminnich@gmail.com> wrote:
> wow, I can't type.
>
> Let me say it more sensibly, even if wrong :-)
> [[[ I know this is wrong, it's kind of "what I want it to do" ]]]
>
> @@
> expression E1, E2;
> statement S;
> function f;
> @@
> f(...){<...
> -if ((E1) && (E2))
> +if (E1 && E2)
> S
> ...> }
>
> Is that any more sensible?

My example adds '== d'...

$ cat /tmp/test.cocci
@@
expression a, b, c, e;
@@
-((a == b) && (c != e))
+a == b && c == d

$ clear;spatch /tmp/test.cocci kernel/locking/lockdep.c
init_defs_builtins: /usr/local/lib/coccinelle/standard.h
HANDLING: kernel/locking/lockdep.c
diff =
--- kernel/locking/lockdep.c
+++ /tmp/cocci-output-9601-607267-lockdep.c
@@ -1420,7 +1420,7 @@ print_shortest_lock_dependencies(struct
  print_stack_trace(&entry->trace, 2);
  printk("\n");

- if (depth == 0 && (entry != root)) {
+ if (depth == 0 && entry == d) {
  printk("lockdep:%s bad path found in chain graph\n", __func__);
  break;
  }
@@ -2322,7 +2322,7 @@ print_irq_inversion_bug(struct task_stru
  /* Find a middle lock (if one exists) */
  depth = get_lock_depth(other);
  do {
- if (depth == 0 && (entry != root)) {
+ if (depth == 0 && entry == d) {
  printk("lockdep:%s bad path found in chain graph\n", __func__);
  break;
  }
@@ -4198,7 +4198,7 @@ retry:
  * if it's not sleeping (or if it's not the current
  * task):
  */
- if (p->state == TASK_RUNNING && p != current)
+ if (p->state == TASK_RUNNING && p == d)
  continue;
  if (p->lockdep_depth)
  lockdep_print_held_locks(p);

Does this help?

[Cocci] elision of unneeded parens

[Peter Senna Tschudin]

_very risky_:

@@
expression a, b;
@@
-(
\(a == b\|a != b\)
-)


On Mon, Oct 12, 2015 at 11:48 PM, Peter Senna Tschudin
<peter.senna@gmail.com> wrote:
> On Mon, Oct 12, 2015 at 11:45 PM, ron minnich <rminnich@gmail.com> wrote:
>> wow, I can't type.
>>
>> Let me say it more sensibly, even if wrong :-)
>> [[[ I know this is wrong, it's kind of "what I want it to do" ]]]
>>
>> @@
>> expression E1, E2;
>> statement S;
>> function f;
>> @@
>> f(...){<...
>> -if ((E1) && (E2))
>> +if (E1 && E2)
>> S
>> ...> }
>>
>> Is that any more sensible?
>
> My example adds '== d'...
>
> $ cat /tmp/test.cocci
> @@
> expression a, b, c, e;
> @@
> -((a == b) && (c != e))
> +a == b && c == d
>
> $ clear;spatch /tmp/test.cocci kernel/locking/lockdep.c
> init_defs_builtins: /usr/local/lib/coccinelle/standard.h
> HANDLING: kernel/locking/lockdep.c
> diff =
> --- kernel/locking/lockdep.c
> +++ /tmp/cocci-output-9601-607267-lockdep.c
> @@ -1420,7 +1420,7 @@ print_shortest_lock_dependencies(struct
>   print_stack_trace(&entry->trace, 2);
>   printk("\n");
>
> - if (depth == 0 && (entry != root)) {
> + if (depth == 0 && entry == d) {
>   printk("lockdep:%s bad path found in chain graph\n", __func__);
>   break;
>   }
> @@ -2322,7 +2322,7 @@ print_irq_inversion_bug(struct task_stru
>   /* Find a middle lock (if one exists) */
>   depth = get_lock_depth(other);
>   do {
> - if (depth == 0 && (entry != root)) {
> + if (depth == 0 && entry == d) {
>   printk("lockdep:%s bad path found in chain graph\n", __func__);
>   break;
>   }
> @@ -4198,7 +4198,7 @@ retry:
>   * if it's not sleeping (or if it's not the current
>   * task):
>   */
> - if (p->state == TASK_RUNNING && p != current)
> + if (p->state == TASK_RUNNING && p == d)
>   continue;
>   if (p->lockdep_depth)
>   lockdep_print_held_locks(p);
>
> Does this help?



-- 
Peter

[Cocci] elision of unneeded parens

[ron minnich]

Peter, many thinks!

I keep thing, however, that it ought to be possible to do something like
if ((E1) relop (E2))
if (E1 relop E2)

Am I asking too much :-)

ron


On Mon, Oct 12, 2015 at 2:54 PM Peter Senna Tschudin <peter.senna@gmail.com>
wrote:

> _very risky_:
>
> @@
> expression a, b;
> @@
> -(
> \(a == b\|a != b\)
> -)
>
>
> On Mon, Oct 12, 2015 at 11:48 PM, Peter Senna Tschudin
> <peter.senna@gmail.com> wrote:
> > On Mon, Oct 12, 2015 at 11:45 PM, ron minnich <rminnich@gmail.com>
> wrote:
> >> wow, I can't type.
> >>
> >> Let me say it more sensibly, even if wrong :-)
> >> [[[ I know this is wrong, it's kind of "what I want it to do" ]]]
> >>
> >> @@
> >> expression E1, E2;
> >> statement S;
> >> function f;
> >> @@
> >> f(...){<...
> >> -if ((E1) && (E2))
> >> +if (E1 && E2)
> >> S
> >> ...> }
> >>
> >> Is that any more sensible?
> >
> > My example adds '== d'...
> >
> > $ cat /tmp/test.cocci
> > @@
> > expression a, b, c, e;
> > @@
> > -((a == b) && (c != e))
> > +a == b && c == d
> >
> > $ clear;spatch /tmp/test.cocci kernel/locking/lockdep.c
> > init_defs_builtins: /usr/local/lib/coccinelle/standard.h
> > HANDLING: kernel/locking/lockdep.c
> > diff =
> > --- kernel/locking/lockdep.c
> > +++ /tmp/cocci-output-9601-607267-lockdep.c
> > @@ -1420,7 +1420,7 @@ print_shortest_lock_dependencies(struct
> >   print_stack_trace(&entry->trace, 2);
> >   printk("\n");
> >
> > - if (depth == 0 && (entry != root)) {
> > + if (depth == 0 && entry == d) {
> >   printk("lockdep:%s bad path found in chain graph\n", __func__);
> >   break;
> >   }
> > @@ -2322,7 +2322,7 @@ print_irq_inversion_bug(struct task_stru
> >   /* Find a middle lock (if one exists) */
> >   depth = get_lock_depth(other);
> >   do {
> > - if (depth == 0 && (entry != root)) {
> > + if (depth == 0 && entry == d) {
> >   printk("lockdep:%s bad path found in chain graph\n", __func__);
> >   break;
> >   }
> > @@ -4198,7 +4198,7 @@ retry:
> >   * if it's not sleeping (or if it's not the current
> >   * task):
> >   */
> > - if (p->state == TASK_RUNNING && p != current)
> > + if (p->state == TASK_RUNNING && p == d)
> >   continue;
> >   if (p->lockdep_depth)
> >   lockdep_print_held_locks(p);
> >
> > Does this help?
>
>
>
> --
> Peter
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://systeme.lip6.fr/pipermail/cocci/attachments/20151013/148dbee2/attachment.html>

[Cocci] elision of unneeded parens

[Julia Lawall]

This seems to work pretty well.  Unfortunately, the spacing is not as nice 
as one would hope for showing off to someone else.

@@
binary operator op = {==,!=};
expression e1,e2,e3,e4,e5;
@@

(
 (e3 || e4)
|
-(
e1 op e2
-)
)
 &&
 e5

@@
binary operator op = {==,!=};
expression e1,e2,e3,e4,e5;
@@

 e5
 &&
(
 (e3 || e4)
|
-(
  e1 op e2
-)
)

-----------------------------------------------------

int main () {
  if ((a == b) && (c != d)) return 12;
  if ((a == b) && (c != d) && (c == d)) return 12;
  if (a == b && (c != d)) return 12;
  if (a == b && (c != d) && (c == d)) return 12;
  if ((a == b) && c != d) return 12;
  if ((a == b) && c != d && (c == d)) return 12;
  if ((a == b) && (c != d) && c == d) return 12;
  if ((a == b) && c != d && c == d) return 12;
  if (a == b && (c != d) && c == d) return 12;
  if ((a == b) + c) return 12;  // should not change
}