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authorDamjan Marion <damarion@cisco.com>2022-01-13 00:28:14 +0100
committerFlorin Coras <florin.coras@gmail.com>2022-01-16 18:54:52 +0000
commit7b90f669d83f432f3610ec0da522bd8ccc4dff01 (patch)
treef2e47bdf50dfa3c353ddc8ff7916b7d4ef50c9d1 /src/vppinfra/bitops.h
parent5233d4619cd0a4a154c35e88ccee92c24cacd377 (diff)
vppinfra: bitops cleanup
Type: refactor Change-Id: I7fa113e924640f9d798c1eb6ae64b9c0a9e2104c Signed-off-by: Damjan Marion <damarion@cisco.com>
Diffstat (limited to 'src/vppinfra/bitops.h')
-rw-r--r--src/vppinfra/bitops.h83
1 files changed, 40 insertions, 43 deletions
diff --git a/src/vppinfra/bitops.h b/src/vppinfra/bitops.h
index 04365699f93..15454ca5036 100644
--- a/src/vppinfra/bitops.h
+++ b/src/vppinfra/bitops.h
@@ -38,18 +38,38 @@
#ifndef included_clib_bitops_h
#define included_clib_bitops_h
-#include <vppinfra/clib.h>
+static_always_inline uword
+clear_lowest_set_bit (uword x)
+{
+#ifdef __BMI__
+ return uword_bits > 32 ? _blsr_u64 (x) : _blsr_u32 (x);
+#else
+ return x & (x - 1);
+#endif
+}
+
+static_always_inline uword
+get_lowest_set_bit (uword x)
+{
+#ifdef __BMI__
+ return uword_bits > 32 ? _blsi_u64 (x) : _blsi_u32 (x);
+#else
+ return x & -x;
+#endif
+}
+
+static_always_inline u8
+get_lowest_set_bit_index (uword x)
+{
+ return uword_bits > 32 ? __builtin_ctzll (x) : __builtin_ctz (x);
+}
/* Population count from Hacker's Delight. */
always_inline uword
count_set_bits (uword x)
{
#ifdef __POPCNT__
-#if uword_bits == 64
- return __builtin_popcountll (x);
-#else
- return __builtin_popcount (x);
-#endif
+ return uword_bits > 32 ? __builtin_popcountll (x) : __builtin_popcount (x);
#else
#if uword_bits == 64
const uword c1 = 0x5555555555555555;
@@ -81,6 +101,15 @@ count_set_bits (uword x)
#endif
}
+#if uword_bits == 64
+#define count_leading_zeros(x) __builtin_clzll (x)
+#else
+#define count_leading_zeros(x) __builtin_clzll (x)
+#endif
+
+#define count_trailing_zeros(x) get_lowest_set_bit_index (x)
+#define log2_first_set(x) get_lowest_set_bit_index (x)
+
/* Based on "Hacker's Delight" code from GLS. */
typedef struct
{
@@ -163,45 +192,13 @@ next_with_same_number_of_set_bits (uword x)
return ripple | ones;
}
-#define foreach_set_bit(var,mask,body) \
-do { \
- uword _foreach_set_bit_m_##var = (mask); \
- uword _foreach_set_bit_f_##var; \
- while (_foreach_set_bit_m_##var != 0) \
- { \
- _foreach_set_bit_f_##var = first_set (_foreach_set_bit_m_##var); \
- _foreach_set_bit_m_##var ^= _foreach_set_bit_f_##var; \
- (var) = min_log2 (_foreach_set_bit_f_##var); \
- do { body; } while (0); \
- } \
-} while (0)
-
-static_always_inline u64
-reset_lowest_set_bit (u64 x)
-{
-#ifdef __BMI__
- return _blsr_u64 (x);
-#else
- return x & (x - 1);
-#endif
-}
+#define foreach_set_bit_index(i, v) \
+ for (uword _tmp = (v) + 0 * (uword) (i = get_lowest_set_bit_index (v)); \
+ _tmp; \
+ i = get_lowest_set_bit_index (_tmp = clear_lowest_set_bit (_tmp)))
-static_always_inline u64
-get_lowest_set_bit (u64 x)
-{
-#ifdef __BMI__
- return _blsi_u64 (x);
#else
- return x & -x;
-#endif
-}
-
-static_always_inline u64
-get_lowest_set_bit_index (u64 x)
-{
- return __builtin_ctzll (x);
-}
-
+#warning "already included"
#endif /* included_clib_bitops_h */
/*