From 932058a5d5f9fd919b90aaa2275d54b37340d585 Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Sat, 23 Aug 2014 07:34:45 +0200 Subject: [PATCH] coccinelle: misc: semantic patch to delete overly complex return code processing MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This semantic patch simplifies cases where the effect of the processing of a function call's return code is just to return the result of the function directly. It may also delete a local return flag variable, if this is no longer used. This was proposed by Uwe Kleine-König. Signed-off-by: Julia Lawall Signed-off-by: Michal Marek --- scripts/coccinelle/misc/simple_return.cocci | 180 ++++++++++++++++++++ 1 file changed, 180 insertions(+) create mode 100644 scripts/coccinelle/misc/simple_return.cocci diff --git a/scripts/coccinelle/misc/simple_return.cocci b/scripts/coccinelle/misc/simple_return.cocci new file mode 100644 index 000000000000..47f7084b6360 --- /dev/null +++ b/scripts/coccinelle/misc/simple_return.cocci @@ -0,0 +1,180 @@ +/// Simplify a trivial if-return sequence. Possibly combine with a +/// preceding function call. +// +// Confidence: High +// Copyright: (C) 2014 Julia Lawall, INRIA/LIP6. GPLv2. +// Copyright: (C) 2014 Gilles Muller, INRIA/LiP6. GPLv2. +// URL: http://coccinelle.lip6.fr/ +// Comments: +// Options: --no-includes --include-headers + +virtual patch +virtual context +virtual org +virtual report + +@r depends on patch@ +local idexpression e; +identifier i,f,fn; +@@ + +fn(...) { <... +- e@i = ++ return + f(...); +-if (i != 0) return i; +-return 0; +...> } + +@depends on patch@ +identifier r.i; +type t; +@@ + +-t i; + ... when != i + +@depends on patch@ +expression e; +@@ + +-if (e != 0) + return e; +-return 0; + +// ----------------------------------------------------------------------- + +@s1 depends on context || org || report@ +local idexpression e; +identifier i,f,fn; +position p,p1,p2; +@@ + +fn(...) { <... +* e@i@p = f(...); + if (\(i@p1 != 0\|i@p2 < 0\)) + return i; + return 0; +...> } + +@s2 depends on context || org || report forall@ +identifier s1.i; +type t; +position q,s1.p; +expression e,f; +@@ + +* t i@q; + ... when != i + e@p = f(...); + +@s3 depends on context || org || report@ +expression e; +position p1!=s1.p1; +position p2!=s1.p2; +@@ + +*if (\(e@p1 != 0\|e@p2 < 0\)) + return e; + return 0; + +// ----------------------------------------------------------------------- + +@script:python depends on org@ +p << s1.p; +p1 << s1.p1; +q << s2.q; +@@ + +cocci.print_main("decl",q) +cocci.print_secs("use",p) +cocci.include_match(False) + +@script:python depends on org@ +p << s1.p; +p2 << s1.p2; +q << s2.q; +@@ + +cocci.print_main("decl",q) +cocci.print_secs("use with questionable test",p) +cocci.include_match(False) + +@script:python depends on org@ +p << s1.p; +p1 << s1.p1; +@@ + +cocci.print_main("use",p) + +@script:python depends on org@ +p << s1.p; +p2 << s1.p2; +@@ + +cocci.print_main("use with questionable test",p) + +@script:python depends on org@ +p << s3.p1; +@@ + +cocci.print_main("test",p) + +@script:python depends on org@ +p << s3.p2; +@@ + +cocci.print_main("questionable test",p) + +// ----------------------------------------------------------------------- + +@script:python depends on report@ +p << s1.p; +p1 << s1.p1; +q << s2.q; +@@ + +msg = "WARNING: end returns can be simpified and declaration on line %s can be dropped" % (q[0].line) +coccilib.report.print_report(p[0],msg) +cocci.include_match(False) + +@script:python depends on report@ +p << s1.p; +p1 << s1.p1; +q << s2.q +; +@@ + +msg = "WARNING: end returns may be simpified if negative or 0 value and declaration on line %s can be dropped" % (q[0].line) +coccilib.report.print_report(p[0],msg) +cocci.include_match(False) + +@script:python depends on report@ +p << s1.p; +p1 << s1.p1; +@@ + +msg = "WARNING: end returns can be simpified" +coccilib.report.print_report(p[0],msg) + +@script:python depends on report@ +p << s1.p; +p2 << s1.p2; +@@ + +msg = "WARNING: end returns can be simpified if negative or 0 value" +coccilib.report.print_report(p[0],msg) + +@script:python depends on report@ +p << s3.p1; +@@ + +msg = "WARNING: end returns can be simpified" +coccilib.report.print_report(p[0],msg) + +@script:python depends on report@ +p << s3.p2; +@@ + +msg = "WARNING: end returns can be simpified if tested value is negative or 0" +coccilib.report.print_report(p[0],msg) -- 2.39.5