cosmopolitan/libc/fmt/divmod10.internal.h

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#ifndef COSMOPOLITAN_LIBC_FMT_DIVMOD10_H_
#define COSMOPOLITAN_LIBC_FMT_DIVMOD10_H_
#if !(__ASSEMBLER__ + __LINKER__ + 0)
forceinline uint64_t DivMod10(uint64_t x, unsigned *r) {
#if defined(__STRICT_ANSI__) || !defined(__GNUC__) || \
(defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__))
*r = x % 10;
return x / 10;
#else
uint128_t dw;
unsigned long long hi, rm;
dw = x;
dw *= 0xcccccccccccccccdull;
hi = dw >> 64;
hi >>= 3;
rm = hi;
rm += rm << 2;
rm += rm;
*r = x - rm;
return hi;
#endif
}
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_FMT_DIVMOD10_H_ */