diff options
Diffstat (limited to 'src/basic/logarithm.h')
-rw-r--r-- | src/basic/logarithm.h | 53 |
1 files changed, 0 insertions, 53 deletions
diff --git a/src/basic/logarithm.h b/src/basic/logarithm.h deleted file mode 100644 index 646f2d3613..0000000000 --- a/src/basic/logarithm.h +++ /dev/null @@ -1,53 +0,0 @@ -/* SPDX-License-Identifier: LGPL-2.1-or-later */ -#pragma once - -#include <stdint.h> - -#include "macro.h" - -/* Note: log2(0) == log2(1) == 0 here and below. */ - -#define CONST_LOG2ULL(x) ((x) > 1 ? (unsigned) __builtin_clzll(x) ^ 63U : 0) -#define NONCONST_LOG2ULL(x) ({ \ - unsigned long long _x = (x); \ - _x > 1 ? (unsigned) __builtin_clzll(_x) ^ 63U : 0; \ - }) -#define LOG2ULL(x) __builtin_choose_expr(__builtin_constant_p(x), CONST_LOG2ULL(x), NONCONST_LOG2ULL(x)) - -static inline unsigned log2u64(uint64_t x) { -#if __SIZEOF_LONG_LONG__ == 8 - return LOG2ULL(x); -#else -# error "Wut?" -#endif -} - -static inline unsigned u32ctz(uint32_t n) { -#if __SIZEOF_INT__ == 4 - return n != 0 ? __builtin_ctz(n) : 32; -#else -# error "Wut?" -#endif -} - -#define CONST_LOG2U(x) ((x) > 1 ? __SIZEOF_INT__ * 8 - __builtin_clz(x) - 1 : 0) -#define NONCONST_LOG2U(x) ({ \ - unsigned _x = (x); \ - _x > 1 ? __SIZEOF_INT__ * 8 - __builtin_clz(_x) - 1 : 0; \ - }) -#define LOG2U(x) __builtin_choose_expr(__builtin_constant_p(x), CONST_LOG2U(x), NONCONST_LOG2U(x)) - -static inline unsigned log2i(int x) { - return LOG2U(x); -} - -static inline unsigned log2u(unsigned x) { - return LOG2U(x); -} - -static inline unsigned log2u_round_up(unsigned x) { - if (x <= 1) - return 0; - - return log2u(x - 1) + 1; -} |