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-rw-r--r--lib/gcd.c78
1 files changed, 0 insertions, 78 deletions
diff --git a/lib/gcd.c b/lib/gcd.c
deleted file mode 100644
index 135ee6407a5e..000000000000
--- a/lib/gcd.c
+++ /dev/null
@@ -1,78 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/gcd.h>
-#include <linux/export.h>
-
-/*
- * This implements the binary GCD algorithm. (Often attributed to Stein,
- * but as Knuth has noted, appears in a first-century Chinese math text.)
- *
- * This is faster than the division-based algorithm even on x86, which
- * has decent hardware division.
- */
-
-#if !defined(CONFIG_CPU_NO_EFFICIENT_FFS) && !defined(CPU_NO_EFFICIENT_FFS)
-
-/* If __ffs is available, the even/odd algorithm benchmarks slower. */
-unsigned long gcd(unsigned long a, unsigned long b)
-{
- unsigned long r = a | b;
-
- if (!a || !b)
- return r;
-
- b >>= __ffs(b);
- if (b == 1)
- return r & -r;
-
- for (;;) {
- a >>= __ffs(a);
- if (a == 1)
- return r & -r;
- if (a == b)
- return a << __ffs(r);
-
- if (a < b)
- swap(a, b);
- a -= b;
- }
-}
-
-#else
-
-/* If normalization is done by loops, the even/odd algorithm is a win. */
-unsigned long gcd(unsigned long a, unsigned long b)
-{
- unsigned long r = a | b;
-
- if (!a || !b)
- return r;
-
- /* Isolate lsbit of r */
- r &= -r;
-
- while (!(b & r))
- b >>= 1;
- if (b == r)
- return r;
-
- for (;;) {
- while (!(a & r))
- a >>= 1;
- if (a == r)
- return r;
- if (a == b)
- return a;
-
- if (a < b)
- swap(a, b);
- a -= b;
- a >>= 1;
- if (a & r)
- a += b;
- a >>= 1;
- }
-}
-
-#endif
-
-EXPORT_SYMBOL_GPL(gcd);