cosmopolitan/libc/bits/popcnt.h

25 lines
968 B
C

#ifndef COSMOPOLITAN_LIBC_BITS_POPCNT_H_
#define COSMOPOLITAN_LIBC_BITS_POPCNT_H_
#include "libc/nexgen32e/x86feature.h"
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
unsigned long popcnt(unsigned long) pureconst;
#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
#define popcnt(X) \
(isconstant(X) ? __builtin_popcountll(X) : ({ \
unsigned long Res, Pop = (X); \
if (X86_HAVE(POPCNT)) { \
asm("popcnt\t%1,%0" : "=r"(Res) : "r"(Pop) : "cc"); \
} else { \
Res = (popcnt)(Pop); \
} \
Res; \
}))
#endif /* GNUC && !ANSI */
COSMOPOLITAN_C_END_
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_BITS_POPCNT_H_ */