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Diffstat (limited to 'include/asm-frv/bitops.h')
-rw-r--r--include/asm-frv/bitops.h96
1 files changed, 89 insertions, 7 deletions
diff --git a/include/asm-frv/bitops.h b/include/asm-frv/bitops.h
index 980ae1b0cd2..1f70d47148b 100644
--- a/include/asm-frv/bitops.h
+++ b/include/asm-frv/bitops.h
@@ -157,23 +157,105 @@ static inline int __test_bit(int nr, const volatile void * addr)
__constant_test_bit((nr),(addr)) : \
__test_bit((nr),(addr)))
-#include <asm-generic/bitops/ffs.h>
-#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/find.h>
-/*
- * fls: find last bit set.
+/**
+ * fls - find last bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as ffs:
+ * - return 32..1 to indicate bit 31..0 most significant bit set
+ * - return 0 to indicate no bits set
*/
#define fls(x) \
({ \
int bit; \
\
- asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x)); \
+ asm(" subcc %1,gr0,gr0,icc0 \n" \
+ " ckne icc0,cc4 \n" \
+ " cscan.p %1,gr0,%0 ,cc4,#1 \n" \
+ " csub %0,%0,%0 ,cc4,#0 \n" \
+ " csub %2,%0,%0 ,cc4,#1 \n" \
+ : "=&r"(bit) \
+ : "r"(x), "r"(32) \
+ : "icc0", "cc4" \
+ ); \
\
- bit ? 33 - bit : bit; \
+ bit; \
})
-#include <asm-generic/bitops/fls64.h>
+/**
+ * fls64 - find last bit set in a 64-bit value
+ * @n: the value to search
+ *
+ * This is defined the same way as ffs:
+ * - return 64..1 to indicate bit 63..0 most significant bit set
+ * - return 0 to indicate no bits set
+ */
+static inline __attribute__((const))
+int fls64(u64 n)
+{
+ union {
+ u64 ll;
+ struct { u32 h, l; };
+ } _;
+ int bit, x, y;
+
+ _.ll = n;
+
+ asm(" subcc.p %3,gr0,gr0,icc0 \n"
+ " subcc %4,gr0,gr0,icc1 \n"
+ " ckne icc0,cc4 \n"
+ " ckne icc1,cc5 \n"
+ " norcr cc4,cc5,cc6 \n"
+ " csub.p %0,%0,%0 ,cc6,1 \n"
+ " orcr cc5,cc4,cc4 \n"
+ " andcr cc4,cc5,cc4 \n"
+ " cscan.p %3,gr0,%0 ,cc4,0 \n"
+ " setlos #64,%1 \n"
+ " cscan.p %4,gr0,%0 ,cc4,1 \n"
+ " setlos #32,%2 \n"
+ " csub.p %1,%0,%0 ,cc4,0 \n"
+ " csub %2,%0,%0 ,cc4,1 \n"
+ : "=&r"(bit), "=r"(x), "=r"(y)
+ : "0r"(_.h), "r"(_.l)
+ : "icc0", "icc1", "cc4", "cc5", "cc6"
+ );
+ return bit;
+
+}
+
+/**
+ * ffs - find first bit set
+ * @x: the word to search
+ *
+ * - return 32..1 to indicate bit 31..0 most least significant bit set
+ * - return 0 to indicate no bits set
+ */
+static inline __attribute__((const))
+int ffs(int x)
+{
+ /* Note: (x & -x) gives us a mask that is the least significant
+ * (rightmost) 1-bit of the value in x.
+ */
+ return fls(x & -x);
+}
+
+/**
+ * __ffs - find first bit set
+ * @x: the word to search
+ *
+ * - return 31..0 to indicate bit 31..0 most least significant bit set
+ * - if no bits are set in x, the result is undefined
+ */
+static inline __attribute__((const))
+int __ffs(unsigned long x)
+{
+ int bit;
+ asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x & -x));
+ return 31 - bit;
+}
+
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/hweight.h>