diff options
Diffstat (limited to 'fpu/softfloat-macros.h')
| -rw-r--r-- | fpu/softfloat-macros.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/fpu/softfloat-macros.h b/fpu/softfloat-macros.h index 9cc6158cb4..c45a23193e 100644 --- a/fpu/softfloat-macros.h +++ b/fpu/softfloat-macros.h @@ -625,6 +625,54 @@ static uint64_t estimateDiv128To64( uint64_t a0, uint64_t a1, uint64_t b ) } +/* From the GNU Multi Precision Library - longlong.h __udiv_qrnnd + * (https://gmplib.org/repo/gmp/file/tip/longlong.h) + * + * Licensed under the GPLv2/LGPLv3 + */ +static uint64_t div128To64(uint64_t n0, uint64_t n1, uint64_t d) +{ + uint64_t d0, d1, q0, q1, r1, r0, m; + + d0 = (uint32_t)d; + d1 = d >> 32; + + r1 = n1 % d1; + q1 = n1 / d1; + m = q1 * d0; + r1 = (r1 << 32) | (n0 >> 32); + if (r1 < m) { + q1 -= 1; + r1 += d; + if (r1 >= d) { + if (r1 < m) { + q1 -= 1; + r1 += d; + } + } + } + r1 -= m; + + r0 = r1 % d1; + q0 = r1 / d1; + m = q0 * d0; + r0 = (r0 << 32) | (uint32_t)n0; + if (r0 < m) { + q0 -= 1; + r0 += d; + if (r0 >= d) { + if (r0 < m) { + q0 -= 1; + r0 += d; + } + } + } + r0 -= m; + + /* Return remainder in LSB */ + return (q1 << 32) | q0 | (r0 != 0); +} + /*---------------------------------------------------------------------------- | Returns an approximation to the square root of the 32-bit significand given | by `a'. Considered as an integer, `a' must be at least 2^31. If bit 0 of |