lkml.org 
[lkml]   [2017]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] coccinelle: orplus: reodganize to improve performance
Adding two #define constants is less common than performing & and |
operations on them, so put the addition first to reduce the set of cases
that have to be considered in detail. At the same time, add & and |
patterns for both arguments of +, to account for commutativity and obtain
more results.

Running time is divided by 3 when applying this to the while kernel on my
laptop with an Intel i5-6200U CPU.

---

diff --git a/scripts/coccinelle/misc/orplus.cocci b/scripts/coccinelle/misc/orplus.cocci
index 81fabf3..08de5be 100644
--- a/scripts/coccinelle/misc/orplus.cocci
+++ b/scripts/coccinelle/misc/orplus.cocci
@@ -14,7 +14,19 @@ virtual report
virtual context

@r@
-constant c;
+constant c,c1;
+identifier i,i1;
+position p;
+@@
+
+(
+ c1 + c - 1
+|
+ c1@i1 +@p c@i
+)
+
+@s@
+constant r.c, r.c1;
identifier i;
expression e;
@@
@@ -27,28 +39,31 @@ e & c@i
e |= c@i
|
e &= c@i
+|
+e | c1@i
+|
+e & c1@i
+|
+e |= c1@i
+|
+e &= c1@i
)

-@s@
-constant r.c,c1;
-identifier i1;
-position p;
+@depends on s@
+position r.p;
+constant c1,c2;
@@

-(
- c1 + c - 1
-|
-*c1@i1 +@p c
-)
+* c1 +@p c2

-@script:python depends on org@
-p << s.p;
+@script:python depends on s && org@
+p << r.p;
@@

cocci.print_main("sum of probable bitmasks, consider |",p)

-@script:python depends on report@
-p << s.p;
+@script:python depends on s && report@
+p << r.p;
@@

msg = "WARNING: sum of probable bitmasks, consider |"
\
 
 \ /
  Last update: 2017-11-12 19:42    [W:1.044 / U:0.488 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site