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#ifndef TREE_SITTER_BITS_H_
#define TREE_SITTER_BITS_H_
#include <stdint.h>
static inline uint32_t bitmask_for_index(uint16_t id) {
return (1u << (31 - id));
}
#ifdef __TINYC__
// Algorithm taken from the Hacker's Delight book
// See also https://graphics.stanford.edu/~seander/bithacks.html
static inline uint32_t count_leading_zeros(uint32_t x) {
int count = 0;
if (x == 0) return 32;
x = x - ((x >> 1) & 0x55555555);
x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
count = (((x + (x >> 4)) & 0x0f0f0f0f) * 0x01010101) >> 24;
return count;
}
#elif defined _WIN32 && !defined __GNUC__
#include <intrin.h>
static inline uint32_t count_leading_zeros(uint32_t x) {
if (x == 0) return 32;
uint32_t result;
_BitScanReverse(&result, x);
return 31 - result;
}
#else
static inline uint32_t count_leading_zeros(uint32_t x) {
if (x == 0) return 32;
return __builtin_clz(x);
}
#endif
#endif // TREE_SITTER_BITS_H_
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