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author | Julia Lawall <Julia.Lawall@lip6.fr> | 2014-08-23 05:34:45 (GMT) |
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committer | Michal Marek <mmarek@suse.cz> | 2014-09-26 11:42:31 (GMT) |
commit | 932058a5d5f9fd919b90aaa2275d54b37340d585 (patch) | |
tree | c23f98f5f4d8fd69401db4092fc067336d944b82 /scripts/coccinelle/misc | |
parent | 22739edfc563fa42f02a2f7323fd352061ef32b3 (diff) | |
download | linux-932058a5d5f9fd919b90aaa2275d54b37340d585.tar.xz |
coccinelle: misc: semantic patch to delete overly complex return code processing
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 <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Diffstat (limited to 'scripts/coccinelle/misc')
-rw-r--r-- | scripts/coccinelle/misc/simple_return.cocci | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/scripts/coccinelle/misc/simple_return.cocci b/scripts/coccinelle/misc/simple_return.cocci new file mode 100644 index 0000000..47f7084 --- /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) |