aboutsummaryrefslogtreecommitdiff
path: root/scripts/coccinelle/inplace-byteswaps.cocci
diff options
context:
space:
mode:
authorPeter Maydell <peter.maydell@linaro.org>2018-10-09 19:16:12 +0100
committerPeter Maydell <peter.maydell@linaro.org>2018-10-16 17:14:55 +0100
commit2ef297af07196c29446556537861f8e7dfeeae7b (patch)
treed9b9e07b71bf83192eb175f423fea97d51a7d013 /scripts/coccinelle/inplace-byteswaps.cocci
parentab44c7b71fa683b9402bea0d367b87c881704188 (diff)
downloadqemu-2ef297af07196c29446556537861f8e7dfeeae7b.zip
qemu-2ef297af07196c29446556537861f8e7dfeeae7b.tar.gz
qemu-2ef297af07196c29446556537861f8e7dfeeae7b.tar.bz2
coccinelle: new inplace-byteswaps.cocci to remove inplace-byteswapping calls
Add a new Coccinelle script which replaces uses of the inplace byteswapping functions *_to_cpus() and cpu_to_*s() with their not-in-place equivalents. This is useful for where the swapping is done on members of a packed struct -- taking the address of the member to pass it to an inplace function is undefined behaviour in C. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20181009181612.10633-1-peter.maydell@linaro.org
Diffstat (limited to 'scripts/coccinelle/inplace-byteswaps.cocci')
-rw-r--r--scripts/coccinelle/inplace-byteswaps.cocci65
1 files changed, 65 insertions, 0 deletions
diff --git a/scripts/coccinelle/inplace-byteswaps.cocci b/scripts/coccinelle/inplace-byteswaps.cocci
new file mode 100644
index 0000000..a869a90
--- /dev/null
+++ b/scripts/coccinelle/inplace-byteswaps.cocci
@@ -0,0 +1,65 @@
+// Replace uses of in-place byteswapping functions with calls to the
+// equivalent not-in-place functions. This is necessary to avoid
+// undefined behaviour if the expression being swapped is a field in a
+// packed struct.
+
+@@
+expression E;
+@@
+-be16_to_cpus(&E);
++E = be16_to_cpu(E);
+@@
+expression E;
+@@
+-be32_to_cpus(&E);
++E = be32_to_cpu(E);
+@@
+expression E;
+@@
+-be64_to_cpus(&E);
++E = be64_to_cpu(E);
+@@
+expression E;
+@@
+-cpu_to_be16s(&E);
++E = cpu_to_be16(E);
+@@
+expression E;
+@@
+-cpu_to_be32s(&E);
++E = cpu_to_be32(E);
+@@
+expression E;
+@@
+-cpu_to_be64s(&E);
++E = cpu_to_be64(E);
+@@
+expression E;
+@@
+-le16_to_cpus(&E);
++E = le16_to_cpu(E);
+@@
+expression E;
+@@
+-le32_to_cpus(&E);
++E = le32_to_cpu(E);
+@@
+expression E;
+@@
+-le64_to_cpus(&E);
++E = le64_to_cpu(E);
+@@
+expression E;
+@@
+-cpu_to_le16s(&E);
++E = cpu_to_le16(E);
+@@
+expression E;
+@@
+-cpu_to_le32s(&E);
++E = cpu_to_le32(E);
+@@
+expression E;
+@@
+-cpu_to_le64s(&E);
++E = cpu_to_le64(E);