Module Name: src
Committed By: riastradh
Date: Mon Aug 27 07:16:50 UTC 2018
Modified Files:
src/sys/external/bsd/common/include/linux: bitops.h
Log Message:
Add find_first_bit, find_next_bit, for_each_set_bit.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/sys/external/bsd/common/include/linux/bitops.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/external/bsd/common/include/linux/bitops.h
diff -u src/sys/external/bsd/common/include/linux/bitops.h:1.5 src/sys/external/bsd/common/include/linux/bitops.h:1.6
--- src/sys/external/bsd/common/include/linux/bitops.h:1.5 Mon Aug 27 07:08:37 2018
+++ src/sys/external/bsd/common/include/linux/bitops.h Mon Aug 27 07:16:50 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: bitops.h,v 1.5 2018/08/27 07:08:37 riastradh Exp $ */
+/* $NetBSD: bitops.h,v 1.6 2018/08/27 07:16:50 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -177,8 +177,8 @@ __test_and_change_bit(unsigned int bit,
}
static inline unsigned long
-find_next_zero_bit(const unsigned long *ptr, unsigned long nbits,
- unsigned long startbit)
+__find_next_bit(const unsigned long *ptr, unsigned long nbits,
+ unsigned long startbit, unsigned long toggle)
{
const size_t bpl = (CHAR_BIT * sizeof(*ptr));
const unsigned long *p = ptr + startbit/bpl;
@@ -195,9 +195,9 @@ find_next_zero_bit(const unsigned long *
/* Do we need to examine a partial starting word? */
if (startbit % bpl) {
/* Are any of the first startbit%bpl bits zero? */
- if (~(*p | (~0UL << (startbit % bpl)))) {
- /* Invert the bits and convert to 64 bits. */
- word = ~(uint64_t)*p;
+ if ((*p ^ toggle) & ~(~0UL << (startbit % bpl))) {
+ /* Toggle the bits and convert to 64 bits. */
+ word = *p ^ toggle;
/* Clear the low startbit%bpl bits. */
word &= ~(~0UL << (startbit % bpl));
@@ -210,14 +210,14 @@ find_next_zero_bit(const unsigned long *
}
}
- /* Find the first word with zeros in it. */
+ /* Find the first word matching word. */
for (; bpl < nbits; p++, result += bpl) {
- if (~*p)
+ if (*p ^ toggle)
break;
}
- /* Invert the bits and convert to 64 bits for ffs64. */
- word = ~(uint64_t)*p;
+ /* Toggle the bits and convert to 64 bits for ffs64. */
+ word = *p ^ toggle;
/* Find the first set bit in this word. */
result += ffs64(word);
@@ -227,11 +227,36 @@ find_next_zero_bit(const unsigned long *
}
static inline unsigned long
+find_next_bit(const unsigned long *ptr, unsigned long nbits,
+ unsigned long startbit)
+{
+ return __find_next_bit(ptr, nbits, startbit, 0);
+}
+
+static inline unsigned long
+find_first_bit(const unsigned long *ptr, unsigned long nbits)
+{
+ return find_next_bit(ptr, nbits, 0);
+}
+
+static inline unsigned long
+find_next_zero_bit(const unsigned long *ptr, unsigned long nbits,
+ unsigned long startbit)
+{
+ return __find_next_bit(ptr, nbits, startbit, ~0UL);
+}
+
+static inline unsigned long
find_first_zero_bit(const unsigned long *ptr, unsigned long nbits)
{
return find_next_zero_bit(ptr, nbits, 0);
}
+#define for_each_set_bit(BIT, PTR, NBITS) \
+ for ((BIT) = find_first_bit((PTR), (NBITS)); \
+ (BIT) < (NBITS); \
+ (BIT) = find_next_bit((PTR), (NBITS), (BIT) + 1))
+
static inline unsigned
hweight8(unsigned w)
{
