#ifndef COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_ #define COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_ #if !(__ASSEMBLER__ + __LINKER__ + 0) COSMOPOLITAN_C_START_ int _bsr(int) pureconst; int _bsrl(long) pureconst; int _bsrll(long long) pureconst; #if defined(__GNUC__) && !defined(__STRICT_ANSI__) #ifdef __x86_64__ int _bsr128(uint128_t) pureconst; #define _bsr(u) \ ({ \ unsigned BiTs; \ asm("bsr\t%0,%0" : "=r"(BiTs) : "0"((unsigned)(u)) : "cc"); \ BiTs; \ }) #define _bsrl(u) \ ({ \ unsigned long BiTs; \ asm("bsr\t%0,%0" : "=r"(BiTs) : "0"((unsigned long)(u)) : "cc"); \ (unsigned)BiTs; \ }) #define _bsrll(u) _bsrl(u) #else #define _bsr(x) (__builtin_clz(x) ^ (sizeof(int) * CHAR_BIT - 1)) #define _bsrl(x) (__builtin_clzl(x) ^ (sizeof(long) * CHAR_BIT - 1)) #define _bsrll(x) (__builtin_clzll(x) ^ (sizeof(long long) * CHAR_BIT - 1)) #endif #endif COSMOPOLITAN_C_END_ #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */ #endif /* COSMOPOLITAN_LIBC_NEXGEN32E_BSR_H_ */