diff options
Diffstat (limited to 'src/math/pow.c')
| -rw-r--r-- | src/math/pow.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/src/math/pow.c b/src/math/pow.c index ac3abc0f..82f684bd 100644 --- a/src/math/pow.c +++ b/src/math/pow.c @@ -146,8 +146,20 @@ double pow(double x, double y) else if ((ix|lx) != 0) /* (|x|<1)**+-inf = 0,inf if x!=0 */ return hy >= 0 ? 0.0 : -y; } - if (iy == 0x3ff00000) /* y is +-1 */ - return hy >= 0 ? x : 1.0/x; + if (iy == 0x3ff00000) { /* y is +-1 */ + if (hy >= 0) + return x; + y = 1/x; +#if FLT_EVAL_METHOD!=0 + { + union {double f; uint64_t i;} u = {y}; + uint64_t i = u.i & -1ULL/2; + if (i>>52 == 0 && (i&(i-1))) + FORCE_EVAL((float)y); + } +#endif + return y; + } if (hy == 0x40000000) /* y is 2 */ return x*x; if (hy == 0x3fe00000) { /* y is 0.5 */ |