diff options
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/s_sin.c | 83 |
1 files changed, 36 insertions, 47 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_sin.c b/sysdeps/ieee754/dbl-64/s_sin.c index 473c0f3f12..93ad8d7619 100644 --- a/sysdeps/ieee754/dbl-64/s_sin.c +++ b/sysdeps/ieee754/dbl-64/s_sin.c @@ -93,6 +93,39 @@ static double csloww (double x, double dx, double orig); static double csloww1 (double x, double dx, double orig); static double csloww2 (double x, double dx, double orig, int n); +/* Reduce range of X and compute sin of a + da. K is the amount by which to + rotate the quadrants. This allows us to use the same routine to compute cos + by simply rotating the quadrants by 1. */ +static inline double +__always_inline +reduce_and_compute (double x, double a, double da, unsigned int k) +{ + double retval = 0; + unsigned int n = __branred (x, &a, &da); + k = (n + k) % 4; + switch (k) + { + case 0: + if (a * a < 0.01588) + retval = bsloww (a, da, x, n); + else + retval = bsloww1 (a, da, x, n); + break; + case 2: + if (a * a < 0.01588) + retval = bsloww (-a, -da, x, n); + else + retval = bsloww1 (-a, -da, x, n); + break; + + case 1: + case 3: + retval = bsloww2 (a, da, x, n); + break; + } + return retval; +} + /*******************************************************************/ /* An ultimate sin routine. Given an IEEE double machine number x */ /* it computes the correctly rounded (to nearest) value of sin(x) */ @@ -366,29 +399,7 @@ __sin (double x) /* -----------------281474976710656 <|x| <2^1024----------------------------*/ else if (k < 0x7ff00000) - { - n = __branred (x, &a, &da); - switch (n) - { - case 0: - if (a * a < 0.01588) - retval = bsloww (a, da, x, n); - else - retval = bsloww1 (a, da, x, n); - break; - case 2: - if (a * a < 0.01588) - retval = bsloww (-a, -da, x, n); - else - retval = bsloww1 (-a, -da, x, n); - break; - - case 1: - case 3: - retval = bsloww2 (a, da, x, n); - break; - } - } /* else if (k < 0x7ff00000 ) */ + retval = reduce_and_compute (x, a, da, 0); /*--------------------- |x| > 2^1024 ----------------------------------*/ else @@ -684,31 +695,9 @@ __cos (double x) } } /* else if (k < 0x42F00000 ) */ + /* 281474976710656 <|x| <2^1024 */ else if (k < 0x7ff00000) - { /* 281474976710656 <|x| <2^1024 */ - - n = __branred (x, &a, &da); - switch (n) - { - case 1: - if (a * a < 0.01588) - retval = bsloww (-a, -da, x, n); - else - retval = bsloww1 (-a, -da, x, n); - break; - case 3: - if (a * a < 0.01588) - retval = bsloww (a, da, x, n); - else - retval = bsloww1 (a, da, x, n); - break; - - case 0: - case 2: - retval = bsloww2 (a, da, x, n); - break; - } - } /* else if (k < 0x7ff00000 ) */ + retval = reduce_and_compute (x, a, da, 1); else { |