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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /lib/clz_ctz.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/clz_ctz.c')
-rw-r--r--lib/clz_ctz.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/lib/clz_ctz.c b/lib/clz_ctz.c
new file mode 100644
index 000000000..2e11e4844
--- /dev/null
+++ b/lib/clz_ctz.c
@@ -0,0 +1,65 @@
+/*
+ * lib/clz_ctz.c
+ *
+ * Copyright (C) 2013 Chanho Min <chanho.min@lge.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ * The functions in this file aren't called directly, but are required by
+ * GCC builtins such as __builtin_ctz, and therefore they can't be removed
+ * despite appearing unreferenced in kernel source.
+ *
+ * __c[lt]z[sd]i2 can be overridden by linking arch-specific versions.
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+
+int __weak __ctzsi2(int val);
+int __weak __ctzsi2(int val)
+{
+ return __ffs(val);
+}
+EXPORT_SYMBOL(__ctzsi2);
+
+int __weak __clzsi2(int val);
+int __weak __clzsi2(int val)
+{
+ return 32 - fls(val);
+}
+EXPORT_SYMBOL(__clzsi2);
+
+int __weak __clzdi2(long val);
+int __weak __ctzdi2(long val);
+#if BITS_PER_LONG == 32
+
+int __weak __clzdi2(long val)
+{
+ return 32 - fls((int)val);
+}
+EXPORT_SYMBOL(__clzdi2);
+
+int __weak __ctzdi2(long val)
+{
+ return __ffs((u32)val);
+}
+EXPORT_SYMBOL(__ctzdi2);
+
+#elif BITS_PER_LONG == 64
+
+int __weak __clzdi2(long val)
+{
+ return 64 - fls64((u64)val);
+}
+EXPORT_SYMBOL(__clzdi2);
+
+int __weak __ctzdi2(long val)
+{
+ return __ffs64((u64)val);
+}
+EXPORT_SYMBOL(__ctzdi2);
+
+#else
+#error BITS_PER_LONG not 32 or 64
+#endif