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| author | H.J. Lu <hjl.tools@gmail.com> | 2017-12-05 08:32:19 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2017-12-05 08:47:27 -0800 |
| commit | 91c318e7b91467984bf68014ef37539d084a34ab (patch) | |
| tree | 2ec4488545ff6dfe0495cd33f07e29a38b17acd4 /sysdeps/ieee754 | |
| parent | c7e882b70563289ac441f2a3565846221e111d00 (diff) | |
| download | glibc-91c318e7b91467984bf68014ef37539d084a34ab.zip glibc-91c318e7b91467984bf68014ef37539d084a34ab.tar.gz glibc-91c318e7b91467984bf68014ef37539d084a34ab.tar.bz2 | |
s_sinf.c: Replace floor with simple casts
Since s_sinf.c either assigns the return value of floor to integer or
passes double converted from integer to floor, this patch replaces
floor with simple casts.
Also since long == int for 32-bit targets, we can use long instead of
int to avoid 64-bit integer for 64-bit targets.
On Skylake, bench-sinf reports performance improvement:
Before After Improvement
max 130.566 129.564 30%
min 7.704 7.706 0%
mean 21.8188 19.1363 30%
* sysdeps/ieee754/flt-32/s_sinf.c (reduced): Replace long with
int.
(SINF_FUNC): Likewise. Replace floor with simple casts.
Diffstat (limited to 'sysdeps/ieee754')
| -rw-r--r-- | sysdeps/ieee754/flt-32/s_sinf.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/sysdeps/ieee754/flt-32/s_sinf.c b/sysdeps/ieee754/flt-32/s_sinf.c index 40d3d19..0b76477 100644 --- a/sysdeps/ieee754/flt-32/s_sinf.c +++ b/sysdeps/ieee754/flt-32/s_sinf.c @@ -85,8 +85,8 @@ static const int ones[] = { +1, -1 }; SIGNBIT is used to add the correct sign after the Chebyshev polynomial is computed. */ static inline float -reduced (const double theta, const unsigned long int n, - const unsigned long int signbit) +reduced (const double theta, const unsigned int n, + const unsigned int signbit) { double sx; const double theta2 = theta * theta; @@ -162,14 +162,14 @@ SINF_FUNC (float x) } else /* |x| >= Pi/4. */ { - unsigned long int signbit = (x < 0); + unsigned int signbit = (x < 0); if (abstheta < 9 * M_PI_4) /* |x| < 9*Pi/4. */ { /* There are cases where FE_UPWARD rounding mode can produce a result of abstheta * inv_PI_4 == 9, where abstheta < 9pi/4, so the domain for pio2_table must go to 5 (9 / 2 + 1). */ - unsigned long int n = (abstheta * inv_PI_4) + 1; + unsigned int n = (abstheta * inv_PI_4) + 1; theta = abstheta - pio2_table[n / 2]; return reduced (theta, n, signbit); } @@ -177,8 +177,8 @@ SINF_FUNC (float x) { if (abstheta < 0x1p+23) /* |x| < 2^23. */ { - unsigned long int n = __floor (abstheta * inv_PI_4) + 1.0; - double x = __floor (n / 2.0); + unsigned int n = ((unsigned int) (abstheta * inv_PI_4)) + 1; + double x = n / 2; theta = x * PI_2_lo + (x * PI_2_hi + abstheta); /* Argument reduction needed. */ return reduced (theta, n, signbit); |