2021-02-16 16:06:17

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH] coccinelle: misc: add minmax script

Check for opencoded min(), max() implementations.

Signed-off-by: Denis Efremov <[email protected]>
---
scripts/coccinelle/misc/minmax.cocci | 198 +++++++++++++++++++++++++++
1 file changed, 198 insertions(+)
create mode 100644 scripts/coccinelle/misc/minmax.cocci

diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
new file mode 100644
index 000000000000..9ae689bb14fb
--- /dev/null
+++ b/scripts/coccinelle/misc/minmax.cocci
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for opencoded min(), max() implementations.
+/// Generated patches sometimes require adding a cast to fix compile warning.
+/// Warnings/patches scope intentionally limited to a function body.
+///
+// Confidence: Medium
+// Copyright: (C) 2021 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: min, max
+//
+
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@rmax depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ ... when any
+* (x cmp y) ?@p x : y
+ ... when any
+}
+
+@rmaxif depends on !patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ ... when any
+* if (x cmp@p y) {
+* max_val = x;
+* } else {
+* max_val = y;
+* }
+ ... when any
+}
+
+@rmin depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ ... when any
+* (x cmp y) ?@p x : y
+ ... when any
+}
+
+@rminif depends on !patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ ... when any
+* if (x cmp@p y) {
+* min_val = x;
+* } else {
+* min_val = y;
+* }
+ ... when any
+}
+
+@depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ ... when any
+- (x cmp y) ? x : y
++ max(x, y)
+ ... when any
+}
+
+@depends on patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ ... when any
+- if (x cmp y) {
+- max_val = x;
+- } else {
+- max_val = y;
+- }
++ max_val = max(x, y);
+ ... when any
+}
+
+@depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ ... when any
+- (x cmp y) ? x : y
++ min(x, y)
+ ... when any
+}
+
+@depends on patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ ... when any
+- if (x cmp y) {
+- min_val = x;
+- } else {
+- min_val = y;
+- }
++ min_val = min(x, y);
+ ... when any
+}
+
+@script:python depends on report@
+p << rmax.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmax.p;
+@@
+
+coccilib.report.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmaxif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmaxif.p;
+@@
+
+coccilib.report.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmin.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rmin.p;
+@@
+
+coccilib.report.print_todo(p[0], "WARNING opportunity for min()")
+
+@script:python depends on report@
+p << rminif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rminif.p;
+@@
+
+coccilib.report.print_todo(p[0], "WARNING opportunity for min()")
--
2.26.2


2021-02-17 21:30:36

by Julia Lawall

[permalink] [raw]
Subject: Re: [PATCH] coccinelle: misc: add minmax script



On Tue, 16 Feb 2021, Denis Efremov wrote:

> Check for opencoded min(), max() implementations.

Some cases that could be improved:

diff -u -p a/drivers/platform/x86/asus-laptop.c
b/drivers/platform/x86/asus-laptop.c
--- a/drivers/platform/x86/asus-laptop.c
+++ b/drivers/platform/x86/asus-laptop.c
@@ -1195,7 +1195,7 @@ static ssize_t ls_level_store(struct dev
if (rv < 0)
return rv;

- value = (0 < value) ? ((15 < value) ? 15 : value) : 0;
+ value = (0 < value) ? (min(15, value)) : 0;
/* 0 <= value <= 15 */
asus_als_level(asus, value);


diff -u -p a/sound/pci/ctxfi/ctatc.c b/sound/pci/ctxfi/ctatc.c
--- a/sound/pci/ctxfi/ctatc.c
+++ b/sound/pci/ctxfi/ctatc.c
@@ -382,7 +382,7 @@ static int atc_pcm_playback_start(struct
apcm->started = 1;

max_cisz = src->multi * src->rsc.msr;
- max_cisz = 0x80 * (max_cisz < 8 ? max_cisz : 8);
+ max_cisz = 0x80 * (min(max_cisz, 8));


> +func(...)
> +{
> + ... when any
> +* (x cmp y) ?@p x : y
> + ... when any
> +}

In all cases, this would be more efficient as:

func(...)
{
<...
* (x cmp y) ?@p x : y
...>
}

There is an optimization that causes this to be just a search through the
nodes of the control-flow graph, rather than following the actual control
flow from the beginning of the function to the end.

> +@script:python depends on report@
> +p << rmax.p;
> +@@
> +
> +coccilib.report.print_report(p[0], "WARNING opportunity for max()")
> +
> +@script:python depends on org@
> +p << rmax.p;
> +@@
> +
> +coccilib.report.print_todo(p[0], "WARNING opportunity for max()")

All of the org cases should be coccilib.org, not coccilib.report.

julia

2021-02-19 09:13:18

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH v2 RESEND] coccinelle: misc: add minmax script

Check for opencoded min(), max() implementations.

Signed-off-by: Denis Efremov <[email protected]>
---

Changes in v2:
- <... ...> instead of ... when any
- org mode reports fixed
- patch rule to drop excessive ()

scripts/coccinelle/misc/minmax.cocci | 224 +++++++++++++++++++++++++++
1 file changed, 224 insertions(+)
create mode 100644 scripts/coccinelle/misc/minmax.cocci

diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
new file mode 100644
index 000000000000..61d6b61fd82c
--- /dev/null
+++ b/scripts/coccinelle/misc/minmax.cocci
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for opencoded min(), max() implementations.
+/// Generated patches sometimes require adding a cast to fix compile warning.
+/// Warnings/patches scope intentionally limited to a function body.
+///
+// Confidence: Medium
+// Copyright: (C) 2021 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: min, max
+//
+
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@rmax depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* x cmp@p y ? x : y
+ ...>
+}
+
+@rmaxif depends on !patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if (x cmp@p y) {
+* max_val = x;
+* } else {
+* max_val = y;
+* }
+ ...>
+}
+
+@rmin depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* x cmp@p y ? x : y
+ ...>
+}
+
+@rminif depends on !patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if (x cmp@p y) {
+* min_val = x;
+* } else {
+* min_val = y;
+* }
+ ...>
+}
+
+@pmax depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>=, >};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- x cmp y ? x : y
++ max(x, y)
+ ...>
+}
+
+@pmaxif depends on patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>=, >};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- if (x cmp y) {
+- max_val = x;
+- } else {
+- max_val = y;
+- }
++ max_val = max(x, y);
+ ...>
+}
+
+@pmin depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<=, <};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- x cmp y ? x : y
++ min(x, y)
+ ...>
+}
+
+@pminif depends on patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<=, <};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- if (x cmp y) {
+- min_val = x;
+- } else {
+- min_val = y;
+- }
++ min_val = min(x, y);
+ ...>
+}
+
+@depends on (pmax || pmaxif || pmin || pminif)@
+identifier func;
+expression x, y;
+position p;
+// FIXME: Coccinelle consumes all available ram and
+// and timeouts on every file.
+// position p = { pmin.p, pminif.p, pmax.p, pmaxif.p };
+@@
+
+func@p(...)
+{
+ <...
+(
+- (min((x), (y)))
++ min(x, y)
+|
+- (max((x), (y)))
++ max(x, y)
+)
+ ...>
+}
+
+@script:python depends on report@
+p << rmax.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmax.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmaxif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmaxif.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmin.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rmin.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for min()")
+
+@script:python depends on report@
+p << rminif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rminif.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for min()")
--
2.26.2

2021-03-05 08:20:30

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH v3] coccinelle: misc: add minmax script

Check for opencoded min(), max() implementations.

Signed-off-by: Denis Efremov <[email protected]>
---
Changes in v2:
- <... ...> instead of ... when any
- org mode reports fixed
- patch rule to drop excessive ()
Changes in v3:
- "depends on patch && (pmax || pmaxif || pmin || pminif)" fixed

scripts/coccinelle/misc/minmax.cocci | 224 +++++++++++++++++++++++++++
1 file changed, 224 insertions(+)
create mode 100644 scripts/coccinelle/misc/minmax.cocci

diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
new file mode 100644
index 000000000000..f577f08d1e6e
--- /dev/null
+++ b/scripts/coccinelle/misc/minmax.cocci
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for opencoded min(), max() implementations.
+/// Generated patches sometimes require adding a cast to fix compile warning.
+/// Warnings/patches scope intentionally limited to a function body.
+///
+// Confidence: Medium
+// Copyright: (C) 2021 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: min, max
+//
+
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@rmax depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* x cmp@p y ? x : y
+ ...>
+}
+
+@rmaxif depends on !patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if (x cmp@p y) {
+* max_val = x;
+* } else {
+* max_val = y;
+* }
+ ...>
+}
+
+@rmin depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* x cmp@p y ? x : y
+ ...>
+}
+
+@rminif depends on !patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if (x cmp@p y) {
+* min_val = x;
+* } else {
+* min_val = y;
+* }
+ ...>
+}
+
+@pmax depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>=, >};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- x cmp y ? x : y
++ max(x, y)
+ ...>
+}
+
+@pmaxif depends on patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>=, >};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- if (x cmp y) {
+- max_val = x;
+- } else {
+- max_val = y;
+- }
++ max_val = max(x, y);
+ ...>
+}
+
+@pmin depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<=, <};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- x cmp y ? x : y
++ min(x, y)
+ ...>
+}
+
+@pminif depends on patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<=, <};
+position p;
+@@
+
+func@p(...)
+{
+ <...
+- if (x cmp y) {
+- min_val = x;
+- } else {
+- min_val = y;
+- }
++ min_val = min(x, y);
+ ...>
+}
+
+@depends on patch && (pmax || pmaxif || pmin || pminif)@
+identifier func;
+expression x, y;
+position p;
+// FIXME: Coccinelle consumes all available ram and
+// and timeouts on every file.
+// position p = { pmin.p, pminif.p, pmax.p, pmaxif.p };
+@@
+
+func@p(...)
+{
+ <...
+(
+- (min((x), (y)))
++ min(x, y)
+|
+- (max((x), (y)))
++ max(x, y)
+)
+ ...>
+}
+
+@script:python depends on report@
+p << rmax.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmax.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmaxif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmaxif.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmin.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rmin.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for min()")
+
+@script:python depends on report@
+p << rminif.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rminif.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for min()")
--
2.26.2

2021-03-06 14:10:35

by Julia Lawall

[permalink] [raw]
Subject: Re: [PATCH v2 RESEND] coccinelle: misc: add minmax script



On Fri, 19 Feb 2021, Denis Efremov wrote:

> Check for opencoded min(), max() implementations.
>
> Signed-off-by: Denis Efremov <[email protected]>
> ---
>
> Changes in v2:
> - <... ...> instead of ... when any
> - org mode reports fixed
> - patch rule to drop excessive ()
>
> scripts/coccinelle/misc/minmax.cocci | 224 +++++++++++++++++++++++++++
> 1 file changed, 224 insertions(+)
> create mode 100644 scripts/coccinelle/misc/minmax.cocci
>
> diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
> new file mode 100644
> index 000000000000..61d6b61fd82c
> --- /dev/null
> +++ b/scripts/coccinelle/misc/minmax.cocci
> @@ -0,0 +1,224 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +///
> +/// Check for opencoded min(), max() implementations.
> +/// Generated patches sometimes require adding a cast to fix compile warning.
> +/// Warnings/patches scope intentionally limited to a function body.
> +///
> +// Confidence: Medium
> +// Copyright: (C) 2021 Denis Efremov ISPRAS
> +// Options: --no-includes --include-headers
> +//
> +// Keywords: min, max
> +//
> +
> +
> +virtual report
> +virtual org
> +virtual context
> +virtual patch
> +
> +@rmax depends on !patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {>, >=};
> +position p;
> +@@
> +
> +func(...)
> +{
> + <...
> +* x cmp@p y ? x : y

The rule below indicated with FIXME is supposed to deal with the
possibility of () that are unnecessary when using min and max. It doesn't
work, because <... P ...> allow P to match 0 or more times, and thus
func@p matches every function.

A simpler solution is to just allow arbitrary () in the pattern, eg:

(x) cmp@p (y) ? (x) : (y)

That will allow each occurrence of x and y to occur with and without
parentheses. In the submitted semantic patch, the () issue was only
considered in the patch case. But it actually affects the purely matching
cases too, because () can be used at one occurrence, but not the other.

> +@script:python depends on report@
> +p << rmax.p;
> +@@
> +
> +coccilib.report.print_report(p[0], "WARNING opportunity for max()")

p is an array because it can be bound to different positions on different
control-flow paths. Notably this occurs with <... ...>. If there are
multiple occurrences of the pattern, there will be one match that contains
all of them. Thus the reporting code should be:

for p0 in p:
coccilib.report.print_report(p0, "WARNING opportunity for max()")

julia

2021-03-08 08:44:56

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH v4] coccinelle: misc: add minmax script

Check for opencoded min(), max() implementations.

Signed-off-by: Denis Efremov <[email protected]>
---
Changes in v2:
- <... ...> instead of ... when any
- org mode reports fixed
- patch rule to drop excessive ()
Changes in v3:
- "depends on patch && (pmax || pmaxif || pmin || pminif)" fixed
Changes in v4:
- refarmatting rule removed
- () brackets added to the patch rules to omit excessive ones
- org/report prints changed to cycle (for p0 in p: ...)

scripts/coccinelle/misc/minmax.cocci | 206 +++++++++++++++++++++++++++
1 file changed, 206 insertions(+)
create mode 100644 scripts/coccinelle/misc/minmax.cocci

diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
new file mode 100644
index 000000000000..63eeba1702ec
--- /dev/null
+++ b/scripts/coccinelle/misc/minmax.cocci
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for opencoded min(), max() implementations.
+/// Generated patches sometimes require adding a cast to fix compile warning.
+/// Warnings/patches scope intentionally limited to a function body.
+///
+// Confidence: Medium
+// Copyright: (C) 2021 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: min, max
+//
+
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@rmax depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* ((x) cmp@p (y) ? (x) : (y))
+ ...>
+}
+
+@rmaxif depends on !patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if ((x) cmp@p (y)) {
+* max_val = (x);
+* } else {
+* max_val = (y);
+* }
+ ...>
+}
+
+@rmin depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* ((x) cmp@p (y) ? (x) : (y))
+ ...>
+}
+
+@rminif depends on !patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if ((x) cmp@p (y)) {
+* min_val = (x);
+* } else {
+* min_val = (y);
+* }
+ ...>
+}
+
+@pmax depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ <...
+- ((x) cmp (y) ? (x) : (y))
++ max(x, y)
+ ...>
+}
+
+@pmaxif depends on patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ <...
+- if ((x) cmp (y)) {
+- max_val = (x);
+- } else {
+- max_val = (y);
+- }
++ max_val = max(x, y);
+ ...>
+}
+
+@pmin depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ <...
+- ((x) cmp (y) ? (x) : (y))
++ min(x, y)
+ ...>
+}
+
+@pminif depends on patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ <...
+- if ((x) cmp (y)) {
+- min_val = (x);
+- } else {
+- min_val = (y);
+- }
++ min_val = min(x, y);
+ ...>
+}
+
+@script:python depends on report@
+p << rmax.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmax.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmaxif.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmaxif.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmin.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rmin.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for min()")
+
+@script:python depends on report@
+p << rminif.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rminif.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for min()")
--
2.26.2

2021-03-08 22:31:10

by Julia Lawall

[permalink] [raw]
Subject: Re: [PATCH v4] coccinelle: misc: add minmax script

> +@pmaxif depends on patch@
> +identifier func;
> +expression x, y;
> +expression max_val;
> +binary operator cmp = {>=, >};
> +@@
> +
> +func(...)
> +{
> + <...
> +- if ((x) cmp (y)) {
> +- max_val = (x);
> +- } else {
> +- max_val = (y);
> +- }
> ++ max_val = max(x, y);
> + ...>
> +}

Things work better if there are no parentheses in max_val = (x) and
max_val = (y). Leaving them there seems to cause the match to work in two
ways, causing an already tagged token error. An example is in
crypto/jitterentropy.c

The same is true of the pminif rule. Only the patch rules are affected.
Double matches are allowed in the context cas, ince there is no real
transfotmation in that case.

julia

> +
> +@pmin depends on patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {<=, <};
> +@@
> +
> +func(...)
> +{
> + <...
> +- ((x) cmp (y) ? (x) : (y))
> ++ min(x, y)
> + ...>
> +}
> +
> +@pminif depends on patch@
> +identifier func;
> +expression x, y;
> +expression min_val;
> +binary operator cmp = {<=, <};
> +@@
> +
> +func(...)
> +{
> + <...
> +- if ((x) cmp (y)) {
> +- min_val = (x);
> +- } else {
> +- min_val = (y);
> +- }
> ++ min_val = min(x, y);
> + ...>
> +}
> +
> +@script:python depends on report@
> +p << rmax.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on org@
> +p << rmax.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on report@
> +p << rmaxif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on org@
> +p << rmaxif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on report@
> +p << rmin.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on org@
> +p << rmin.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on report@
> +p << rminif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on org@
> +p << rminif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for min()")
> --
> 2.26.2
>
>

2021-03-09 06:41:07

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH v5] coccinelle: misc: add minmax script

Check for opencoded min(), max() implementations.

Signed-off-by: Denis Efremov <[email protected]>
---
Changes in v2:
- <... ...> instead of ... when any
- org mode reports fixed
- patch rule to drop excessive ()
Changes in v3:
- "depends on patch && (pmax || pmaxif || pmin || pminif)" fixed
Changes in v4:
- refarmatting rule removed
- () brackets added to the patch rules to omit excessive ones
- org/report prints changed to cycle (for p0 in p: ...)
Changes in v5:
- parentheses droppped in pminif and pmaxif rules (max_val = x ...)

scripts/coccinelle/misc/minmax.cocci | 206 +++++++++++++++++++++++++++
1 file changed, 206 insertions(+)
create mode 100644 scripts/coccinelle/misc/minmax.cocci

diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
new file mode 100644
index 000000000000..eccdd3eb3452
--- /dev/null
+++ b/scripts/coccinelle/misc/minmax.cocci
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for opencoded min(), max() implementations.
+/// Generated patches sometimes require adding a cast to fix compile warning.
+/// Warnings/patches scope intentionally limited to a function body.
+///
+// Confidence: Medium
+// Copyright: (C) 2021 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: min, max
+//
+
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@rmax depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* ((x) cmp@p (y) ? (x) : (y))
+ ...>
+}
+
+@rmaxif depends on !patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>, >=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if ((x) cmp@p (y)) {
+* max_val = (x);
+* } else {
+* max_val = (y);
+* }
+ ...>
+}
+
+@rmin depends on !patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* ((x) cmp@p (y) ? (x) : (y))
+ ...>
+}
+
+@rminif depends on !patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<, <=};
+position p;
+@@
+
+func(...)
+{
+ <...
+* if ((x) cmp@p (y)) {
+* min_val = (x);
+* } else {
+* min_val = (y);
+* }
+ ...>
+}
+
+@pmax depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ <...
+- ((x) cmp (y) ? (x) : (y))
++ max(x, y)
+ ...>
+}
+
+@pmaxif depends on patch@
+identifier func;
+expression x, y;
+expression max_val;
+binary operator cmp = {>=, >};
+@@
+
+func(...)
+{
+ <...
+- if ((x) cmp (y)) {
+- max_val = x;
+- } else {
+- max_val = y;
+- }
++ max_val = max(x, y);
+ ...>
+}
+
+@pmin depends on patch@
+identifier func;
+expression x, y;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ <...
+- ((x) cmp (y) ? (x) : (y))
++ min(x, y)
+ ...>
+}
+
+@pminif depends on patch@
+identifier func;
+expression x, y;
+expression min_val;
+binary operator cmp = {<=, <};
+@@
+
+func(...)
+{
+ <...
+- if ((x) cmp (y)) {
+- min_val = x;
+- } else {
+- min_val = y;
+- }
++ min_val = min(x, y);
+ ...>
+}
+
+@script:python depends on report@
+p << rmax.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmax.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmaxif.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for max()")
+
+@script:python depends on org@
+p << rmaxif.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for max()")
+
+@script:python depends on report@
+p << rmin.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rmin.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for min()")
+
+@script:python depends on report@
+p << rminif.p;
+@@
+
+for p0 in p:
+ coccilib.report.print_report(p0, "WARNING opportunity for min()")
+
+@script:python depends on org@
+p << rminif.p;
+@@
+
+for p0 in p:
+ coccilib.org.print_todo(p0, "WARNING opportunity for min()")
--
2.26.2

2021-03-20 21:35:59

by Julia Lawall

[permalink] [raw]
Subject: Re: [PATCH v5] coccinelle: misc: add minmax script



On Tue, 9 Mar 2021, Denis Efremov wrote:

> Check for opencoded min(), max() implementations.
>
> Signed-off-by: Denis Efremov <[email protected]>

Applied, thanks.

julia

> ---
> Changes in v2:
> - <... ...> instead of ... when any
> - org mode reports fixed
> - patch rule to drop excessive ()
> Changes in v3:
> - "depends on patch && (pmax || pmaxif || pmin || pminif)" fixed
> Changes in v4:
> - refarmatting rule removed
> - () brackets added to the patch rules to omit excessive ones
> - org/report prints changed to cycle (for p0 in p: ...)
> Changes in v5:
> - parentheses droppped in pminif and pmaxif rules (max_val = x ...)
>
> scripts/coccinelle/misc/minmax.cocci | 206 +++++++++++++++++++++++++++
> 1 file changed, 206 insertions(+)
> create mode 100644 scripts/coccinelle/misc/minmax.cocci
>
> diff --git a/scripts/coccinelle/misc/minmax.cocci b/scripts/coccinelle/misc/minmax.cocci
> new file mode 100644
> index 000000000000..eccdd3eb3452
> --- /dev/null
> +++ b/scripts/coccinelle/misc/minmax.cocci
> @@ -0,0 +1,206 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +///
> +/// Check for opencoded min(), max() implementations.
> +/// Generated patches sometimes require adding a cast to fix compile warning.
> +/// Warnings/patches scope intentionally limited to a function body.
> +///
> +// Confidence: Medium
> +// Copyright: (C) 2021 Denis Efremov ISPRAS
> +// Options: --no-includes --include-headers
> +//
> +// Keywords: min, max
> +//
> +
> +
> +virtual report
> +virtual org
> +virtual context
> +virtual patch
> +
> +@rmax depends on !patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {>, >=};
> +position p;
> +@@
> +
> +func(...)
> +{
> + <...
> +* ((x) cmp@p (y) ? (x) : (y))
> + ...>
> +}
> +
> +@rmaxif depends on !patch@
> +identifier func;
> +expression x, y;
> +expression max_val;
> +binary operator cmp = {>, >=};
> +position p;
> +@@
> +
> +func(...)
> +{
> + <...
> +* if ((x) cmp@p (y)) {
> +* max_val = (x);
> +* } else {
> +* max_val = (y);
> +* }
> + ...>
> +}
> +
> +@rmin depends on !patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {<, <=};
> +position p;
> +@@
> +
> +func(...)
> +{
> + <...
> +* ((x) cmp@p (y) ? (x) : (y))
> + ...>
> +}
> +
> +@rminif depends on !patch@
> +identifier func;
> +expression x, y;
> +expression min_val;
> +binary operator cmp = {<, <=};
> +position p;
> +@@
> +
> +func(...)
> +{
> + <...
> +* if ((x) cmp@p (y)) {
> +* min_val = (x);
> +* } else {
> +* min_val = (y);
> +* }
> + ...>
> +}
> +
> +@pmax depends on patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {>=, >};
> +@@
> +
> +func(...)
> +{
> + <...
> +- ((x) cmp (y) ? (x) : (y))
> ++ max(x, y)
> + ...>
> +}
> +
> +@pmaxif depends on patch@
> +identifier func;
> +expression x, y;
> +expression max_val;
> +binary operator cmp = {>=, >};
> +@@
> +
> +func(...)
> +{
> + <...
> +- if ((x) cmp (y)) {
> +- max_val = x;
> +- } else {
> +- max_val = y;
> +- }
> ++ max_val = max(x, y);
> + ...>
> +}
> +
> +@pmin depends on patch@
> +identifier func;
> +expression x, y;
> +binary operator cmp = {<=, <};
> +@@
> +
> +func(...)
> +{
> + <...
> +- ((x) cmp (y) ? (x) : (y))
> ++ min(x, y)
> + ...>
> +}
> +
> +@pminif depends on patch@
> +identifier func;
> +expression x, y;
> +expression min_val;
> +binary operator cmp = {<=, <};
> +@@
> +
> +func(...)
> +{
> + <...
> +- if ((x) cmp (y)) {
> +- min_val = x;
> +- } else {
> +- min_val = y;
> +- }
> ++ min_val = min(x, y);
> + ...>
> +}
> +
> +@script:python depends on report@
> +p << rmax.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on org@
> +p << rmax.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on report@
> +p << rmaxif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on org@
> +p << rmaxif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for max()")
> +
> +@script:python depends on report@
> +p << rmin.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on org@
> +p << rmin.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on report@
> +p << rminif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.report.print_report(p0, "WARNING opportunity for min()")
> +
> +@script:python depends on org@
> +p << rminif.p;
> +@@
> +
> +for p0 in p:
> + coccilib.org.print_todo(p0, "WARNING opportunity for min()")
> --
> 2.26.2
>
>