File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/tile/include/asm/word-at-a-time.h b/arch/tile/include/asm/word-at-a-time.h
new file mode 100644
index 0000000..b66a693
--- /dev/null
+++ b/arch/tile/include/asm/word-at-a-time.h
@@ -0,0 +1,42 @@
+#ifndef _ASM_WORD_AT_A_TIME_H
+#define _ASM_WORD_AT_A_TIME_H
+
+#include <asm/byteorder.h>
+
+struct word_at_a_time { /* unused */ };
+#define WORD_AT_A_TIME_CONSTANTS {}
+
+/* Generate 0x01 byte values for zero bytes using a SIMD instruction. */
+static inline unsigned long has_zero(unsigned long val, unsigned long *data,
+				     const struct word_at_a_time *c)
+{
+#ifdef __tilegx__
+	unsigned long mask = __insn_v1cmpeqi(val, 0);
+#else /* tilepro */
+	unsigned long mask = __insn_seqib(val, 0);
+#endif
+	*data = mask;
+	return mask;
+}
+
+/* These operations are both nops. */
+#define prep_zero_mask(val, data, c) (data)
+#define create_zero_mask(data) (data)
+
+/* And this operation just depends on endianness. */
+static inline long find_zero(unsigned long mask)
+{
+#ifdef __BIG_ENDIAN
+	return __builtin_clzl(mask) >> 3;
+#else
+	return __builtin_ctzl(mask) >> 3;
+#endif
+}
+
+#ifdef __BIG_ENDIAN
+#define zero_bytemask(mask) (~1ul << (63 - __builtin_clzl(mask)))
+#else
+#define zero_bytemask(mask) ((2ul << __builtin_ctzl(mask)) - 1)
+#endif
+
+#endif /* _ASM_WORD_AT_A_TIME_H */