The powerpc word-at-a-time functions are big endian specific.
Bring in the x86 version in order to support little endian builds.
Signed-off-by: Anton Blanchard <an...@samba.org>
---
arch/powerpc/include/asm/word-at-a-time.h | 71 +++++++++++++++++++++++++++++++
1 file changed, 71 insertions(+)
diff --git a/arch/powerpc/include/asm/word-at-a-time.h
b/arch/powerpc/include/asm/word-at-a-time.h
index d0b6d4a..213a5f2 100644
--- a/arch/powerpc/include/asm/word-at-a-time.h
+++ b/arch/powerpc/include/asm/word-at-a-time.h
@@ -8,6 +8,8 @@
#include <linux/kernel.h>
#include <asm/asm-compat.h>
+#ifdef __BIG_ENDIAN__
+
struct word_at_a_time {
const unsigned long high_bits, low_bits;
};
@@ -38,4 +40,73 @@ static inline bool has_zero(unsigned long val, unsigned long
*data, const struct
return (val + c->high_bits) & ~rhs;
}
+#else
+
+/*
+ * This is largely generic for little-endian machines, but the
+ * optimal byte mask counting is probably going to be something
+ * that is architecture-specific. If you have a reliably fast
+ * bit count instruction, that might be better than the multiply
+ * and shift, for example.
+ */
+struct word_at_a_time {
+ const unsigned long one_bits, high_bits;
+};
+
+#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
+
+#ifdef CONFIG_64BIT
+
+/*
+ * Jan Achrenius on G+: microoptimized version of
+ * the simpler "(mask & ONEBYTES) * ONEBYTES >> 56"
+ * that works for the bytemasks without having to
+ * mask them first.
+ */
+static inline long count_masked_bytes(unsigned long mask)
+{
+ return mask*0x0001020304050608ul >> 56;
+}
+
+#else /* 32-bit case */
+
+/* Carl Chatfield / Jan Achrenius G+ version for 32-bit */
+static inline long count_masked_bytes(long mask)
+{
+ /* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
+ long a = (0x0ff0001+mask) >> 23;
+ /* Fix the 1 for 00 case */
+ return a & mask;
+}
+
+#endif
+
+/* Return nonzero if it has a zero */
+static inline unsigned long has_zero(unsigned long a, unsigned long *bits,
const struct word_at_a_time *c)
+{
+ unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
+ *bits = mask;
+ return mask;
+}
+
+static inline unsigned long prep_zero_mask(unsigned long a, unsigned long
bits, const struct word_at_a_time *c)
+{
+ return bits;
+}
+
+static inline unsigned long create_zero_mask(unsigned long bits)
+{
+ bits = (bits - 1) & ~bits;
+ return bits >> 7;
+}
+
+/* The mask we created is directly usable as a bytemask */
+#define zero_bytemask(mask) (mask)
+
+static inline unsigned long find_zero(unsigned long mask)
+{
+ return count_masked_bytes(mask);
+}
+#endif
+
#endif /* _ASM_WORD_AT_A_TIME_H */
--
1.8.1.2
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