Szabolcs Nagy
b12a73d5bf
modifications: * avoid unsigned->signed conversions * removed various volatile hacks * use FORCE_EVAL when evaluating only for side-effects * factor out R() rational approximation instead of manual inline * __invtrigl.h now only provides __invtrigl_R, __pio2_hi and __pio2_lo * use 2*pio2_hi, 2*pio2_lo instead of pi_hi, pi_lo otherwise the logic is not changed, long double versions will need a revisit when a genaral long double cleanup happens
32 lines
951 B
C
32 lines
951 B
C
#include "__invtrigl.h"
|
|
|
|
#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
|
|
|
|
static const long double
|
|
pS0 = 1.66666666666666666631e-01L,
|
|
pS1 = -4.16313987993683104320e-01L,
|
|
pS2 = 3.69068046323246813704e-01L,
|
|
pS3 = -1.36213932016738603108e-01L,
|
|
pS4 = 1.78324189708471965733e-02L,
|
|
pS5 = -2.19216428382605211588e-04L,
|
|
pS6 = -7.10526623669075243183e-06L,
|
|
qS1 = -2.94788392796209867269e+00L,
|
|
qS2 = 3.27309890266528636716e+00L,
|
|
qS3 = -1.68285799854822427013e+00L,
|
|
qS4 = 3.90699412641738801874e-01L,
|
|
qS5 = -3.14365703596053263322e-02L;
|
|
|
|
const long double pio2_hi = 1.57079632679489661926L;
|
|
const long double pio2_lo = -2.50827880633416601173e-20L;
|
|
|
|
/* used in asinl() and acosl() */
|
|
/* R(x^2) is a rational approximation of (asin(x)-x)/x^3 with Remez algorithm */
|
|
long double __invtrigl_R(long double z)
|
|
{
|
|
long double p, q;
|
|
p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*(pS5+z*pS6))))));
|
|
q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*qS5))));
|
|
return p/q;
|
|
}
|
|
#endif
|